INTERNAL REPORT Removal and Utilization of High Risk ...ucanr.edu/sites/WoodyBiomass/newsletters/Final_Report31540.pdf · INTERNAL REPORT Removal and Utilization of High Risk Sudden

INTERNAL REPORT

Removal and Utilization of High Risk Sudden Oak Death Host Material

Final Report

September 30, 2005

Period covered: June 1, 2002 to June 30, 2005

John R. Shelly, CE Advisor Ramnik Singh, Post Graduate Researcher

Christine Langford, Staff Research Associate University of California

Division of Agriculture and Natural Resources Richmond Field Station, Building 478

Richmond, California 94720

and

Tad Mason TSS Consultants

Rancho Cordova, California

Project Funded by California Department of Forestry and Fire Protection Agreement No. 8CA01257

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Table of Contents Introduction............................................................................................................................... 3 Objectives ................................................................................................................................. 4 Major Tasks Completed............................................................................................................ 4 Methods..................................................................................................................................... 5

Culture techniques ................................................................................................................ 7 Utilization analysis................................................................................................................ 7

Results....................................................................................................................................... 8 Monitoring for changes in SOD infestation.......................................................................... 9

Host vegetation ................................................................................................................. 9 Beetle activity ................................................................................................................. 11 Monitoring of Delivered Materials ................................................................................. 14

Analysis of Wood properties and lumber quality ............................................................... 17 Wood Properties.............................................................................................................. 17 Lumber Quality............................................................................................................... 18 Densified Fuel................................................................................................................. 20

Discussion............................................................................................................................... 22 Summary ................................................................................................................................. 23

Project Highlights ............................................................................................................... 24 Acknowledgments................................................................................................................... 28 Appendix I – Progress Updates Covering January to June 2005............................................ 29 Appendix II – Presentations and Articles Delivered in 2005 ................................................. 36

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Introduction This project was initiated in response to concerns raised by the California Oak Mortality Task Force (COMTF) that disposing or utilizing Sudden Oak Death-diseased (SOD) woody materials would spread this disease that is known to be lethal in some host hardwood trees, especially red oaks. The potential to spread plant diseases by moving infected plants and plant materials from one location to another is well documented in the literature (Erwin and Ribeiro 1996) (Garbelotto 2003) (Davidson et al. 2002). The list of host plants for Phytophthora ramorum (P. ramorum), the primary pathogen of the disease, continues to grow with the possibility that many of the tree species of California’s forests could become hosts (Garbelotto 2003). Unlike most other Phytophthora species, P. ramorum cankers are found highly associated with the bark of some host trees (Storer et al. 2001). Also, two beetles of the Scolytidae family, the western oak bark beetle (Pseudopityophthorous pubipennis) and the oak ambrosia beetle (Monarthrum sp.) are known to be highly associated with this disease in trees (Storer et al. 2001). However, the role these beetles play in the spread of the disease is not well understood since the high incidence of attack appears to coincide with the latter stages of the disease (Furniss and Carolin 1977). Although it is considered unlikely that the beetles play a significant role in disease spread, they could be a valuable tool for measuring SOD activity in a region. Regulatory agencies, recognizing that the likely pathways for the spread of P. ramorum are by water, soil, air, and the movement of infected plant materials, recommend that infected material be quarantined and left in place if possible. However, it is not always possible to leave infected material at the site of the infestation. Many SOD-diseased trees are in urban areas, public areas, or adjacent to houses, roads, or utility lines. Such trees are often considered hazard trees and they must be removed. The removal of large numbers of these trees results in high, unbudgeted expenditures and often a disposal problem. As a woody material, this biomass could generate some value as consumer products but it was unclear if utilization activities can contribute to the spread of the disease. Based on the premise that P. ramorum in trees thrives only on foliage or directly beneath the bark, wood and wood products could be exempt from regulations as long as they were free of bark. However, the actual risk of spreading the disease by moving wood and wood products, with or without bark, was not well understood. The goals of the project reported in this paper were to study the risks of moving material infected with P. ramorum from the site of its initial infection to a central location or processing facility and to identify potential uses for the diseased material. The approach used to gauge the risks was to track the infestation levels of P. ramorum and bark beetles in and around collection yards and processing facilities during the life of the project. Work performed on this project from its inception to December 31, 2004 was reported in detail in 5 progress reports (Shelly et. al. 2003a,b; 2004a,b; 2005a); work performed from January 1, 2005 to June 30, 2005 (project end date) is included in this report (Appendix 1). Preliminary results were delivered through various methods including a presentation at the Sudden Oak Death Science Symposium II, January 2005 (Shelly 2005b); see Appendix 2.

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Two collection yards for SOD-diseased wood were actively managed under this project. A Marin County collection yard was located at Marin Resource and Recovery in San Rafael, California and a Santa Cruz County yard was located at the Santa Cruz County transfer station in Ben Lomond, California. In addition, SOD-diseased material was monitored at a sawmill in Davenport, California and a biomass power plant in Soledad, California, and a densified fuelwood mill in Watsonville, California. All of these sites actively participated in the project. The project goals included:

1. Development of protocols for transporting, storing and processing SOD-diseased wood,

2. Evaluating the risk of spreading SOD through utilization activities, 3. Finding the best use(s) for SOD-diseased wood.

A Coordinating Committee consisting of representatives of County, State, and Federal agencies as well as local private interests was formed. This committee met as needed and provided general oversight to the project, comments on testing and monitoring protocols, and participated in reviewing project documents and findings.

Objectives The overall objectives of the project included:

• Design a comprehensive disposal and utilization plan for Marin and Santa Cruz Counties that incorporates the views of public agencies and private enterprise.

• Develop protocols for the removal and transportation of SOD-diseased woody material and for monitoring the potential spread of disease

• Evaluate the relationship between transporting and processing SOD-diseased wood and the risk of spreading SOD disease

• Evaluate the basic wood properties of SOD-diseased wood and the value-added utilization potential and facilitate the distribution of SOD-diseased wood to appropriate markets.

Major Tasks Completed The plan for the development of two collection yards designed to accept Sudden Oak Death-diseased wood began in June, 2002 with input from numerous county and state stakeholders including private enterprise. This plan included sampling designs, monitoring protocols, and operation procedures. The two collection yards were operated continuously through the life of the project. All material received was either processed into an approved product (according to applicable state regulations) or used for the testing and research phases of the project. Table 1 below lists the major milestones in the project. The specific details were presented in Progress Reports 1 – 5.

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Table 1. Project Milestones

Activities and Tasks Initiated Completed Grant awarded to University of California Forest Products Lab

August 16, 2002

Design Disposal and Utilization Plan June 19, 2002 January 6, 2003

Project oversight and working committees formed

July 1, 2002 December 31, 2002

Project Meetings Implementation Team (27 mtgs)

Steering/Coordinating Committee (6 mtgs)

June 19, 2002

October 15, 2002

June 30, 2005

August 13, 2004

Contracts for coordination and operation of 2 collection yards

Operations/Management Company Marin County

Santa Cruz County

October 1, 2002 April 30, 2003

October 31, 2003

June 30, 2005 June 30, 2005 June 30, 2005

Operate Collection Yards Marin County

Santa Cruz County

May 7, 2003

December 12, 2003

June 30, 2005 June 30, 2005

Outreach and Education Set up and maintain Web Site

Newsletter and media articles (4 articles) Direct communication with tree service professionals

Toll free telephone information Service Host 3 media days at collection yards

Distribute Progress Reports (5 bi-annual reports) Distribute 31 Monthly Updates

Presentations at scientific, technical, and tree service/arborist meetings

(> 10 presentations)

January 6, 2003 January 6, 2003 March 6, 2003 April 14, 2003 May 7, 2003

January 17, 2003 January 8, 2003 June 25, 2002

June 30, 2005 June 30, 2005 June 30, 2005 June 30, 2005 May 7, 2004

February 1, 2005 July 15, 2005

March 31, 2005

Research Survey of tree service companies

Develop monitoring protocols and sampling procedures

Sample delivered materials and vegetation in and around each collection yard for P. ramorum in

accordance with sampling and testing protocols Analyze spread of SOD at each collection yard

Analyze wood properties Evaluate potential products

November 20, 2002

January 6, 2003

April 7, 2003

December 1, 2003 August 1, 2003

December 30, 2003

July 1, 2003 April1, 2004

June 30, 2005

June 30, 2005 June 30, 2005 June 30, 2005

Methods To create a disposal and utilization plan that addressed the objectives of the project, a series of meetings was conducted with representatives of interested organizations and stakeholders. These included state, county, and federal agencies responsible for the removal and disposal of woody biomass as well as tree service companies, arborists, land managers, and commercial users of woody biomass. An outcome of these meetings was the establishment of two collection yards to serve as a central location for the drop-off of host trees suspected of having SOD.

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Consultations with state/federal regulators and other researchers studying SOD led to a set of protocols used in this project to define the rules of participation in the project and the methods used to monitor the activities. Only host material suspected of being infected with P. ramorum and identified by a person having received training in SOD symptoms was accepted at the collection yards. This material had to be removed and transported to the collection yard by a tree service company or other qualified expert following the transportation guidelines distributed to all potential participants and also posted on the project Internet website (http://groups.ucanr.org/sodbusters). Once at the yard, the SOD-diseased material temporarily stored at the site was physically separated from other woody biomass operations. This material was stored until enough volume was collected to justify moving it to a utilization market. During this sequence of events the material, the site, surrounding environment, and processing activities were monitored for the presence of P. ramorum and Scolytidae sp. activity according to the protocols described in an earlier progress report (Shelly et al. 2004). In summary, the following monitoring was conducted according to the schedule outlined in Table 2.

• Determined base line levels of infestation in the area surrounding the collection yard by inspecting all of the following host plants found inside 6 meter (20 ft) circular plots spaced 20 meters (66 ft) apart along transects emanating from the collection yard.

o Coast live oak (Quercus agrifolia) – inspected for SOD symptoms o California bay laurel (Umbellularia californica) – collected symptomatic

leaves from trees taller than 2 meters that were used for laboratory examination (see culture techniques below)

• Monitored beetle levels by capturing insects in ethanol-baited, beetle traps and periodically counting the catch of scolytids.

• Periodically sampled the following collection yard materials o Delivered SOD-diseased woody biomass (chips, branches, leaves, and logs) o P. ramorum susceptible rhododendron plants (Rhododendron var. Colonel

Coen), potted and placed in the collection yard (sentinel rhododendrons) o Airborne dust generated during unloading of SOD-diseased material from

trucks (only at the Marin County yard and the Soledad biomass power plant) o Rain water runoff from chip piles (only at the Marin County yard)

• Periodically sampled the following materials during processing activities o Airborne dust generated during wood grinding operations o Small wood particles that fall from the grinders (grinder fines) o Firewood with bark as it was processed o Sawdust from sawmill as logs were processed into lumber

• Periodically sampled processed firewood as it dried

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Table 2 – Schedule of sampling at each collection yard (M = Marin County collection yard, SC = Santa Cruz County collection yard, SM = sawmill site in Davenport, S= Soledad biomass power plant)

Item Sampled Every 2

weeks

Every Month

Every 2 months

Every 6 months

As needed

Host plants in sample plots M, SC, SM Sentinel rhododendrons M, SC SM, S Beetles M, SC SM Rain water runoff from collection yard

M

Delivered chip material and CA bay laurel leaves

M, SC

Delivered sawlogs SC Airborne dust generated during delivery

M S

Grinder fines and sawdust M, SC, SM Lumber SM Freshly split Firewood M, SC, SM Stored firewood M, SM

Culture techniques All chip, wood particle, dust, water and solid wood samples were subjected to a commonly used laboratory pear baiting technique to determine the presence of P. ramorum. Hard, green d'Anjou pears without wounds or bruises were partially submerged for 3 days at 20°C in deionized water containing the material being tested. The pears were then removed from the water and air dried at 20°C for 2-5 days. Any characteristic Phytophthora lesions that appeared on the pears were isolated and placed on an agar growth medium prepared with ampicillin, rifampicin, and pimaricin (PARP) using sterile techniques. Organisms that grew on the PARP plate were examined for P. ramorum characteristics to determine the presence of the pathogen. Leaves collected from host plants were not pear-baited; the Phytophthora lesions on the leaves were divided into two parts, one part was directly plated on the PARP and the second was used for DNA analysis. The Plant Pest Diagnostics Center, California Department of Food and Agriculture (CDFA) in Sacramento performed the DNA analysis using polymerase chain reaction (PCR) techniques to confirm the presence of P. ramorum on the suspect leaves. Utilization analysis Data gathered on the properties of the diseased wood collected in the study area included tree size and form, gross wood characteristics, wood moisture content at the time of the diseased wood delivery, and wood density. Moisture content was measured on solid wood specimens taken from the processed firewood and logs selected for lumber processing. The same specimens were also used to measure the density. These properties were used to determine the level of degradation in the wood and to identify the best use for the material. Products considered included biomass powerplant fuel, lumber, firewood, and densified fuel logs.

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Results A total of 1,246 tons of potentially SOD-diseased wood was delivered and processed at the two collection yards (Table 3). In the 25-month period from May 2003 to June 2005, the Marin County collection yard received 915 tons from 14 private tree service companies and 3 public works departments. The Santa Cruz County collection yard received 331 tons in the 18-month period from December 2003 to June 2005, the majority as hazard tree removals from tree service companies under contract with the County of Santa Cruz during the 7-month period from December 2003 to June 2004. At the Marin County yard the deliveries were tracked by species. Of the 995 trees removed and delivered to the yard, 817 (82%) were tanoak (Lithocarpus densiflorus), 169 (17%) were coast live oak (Quercus agrifolia), 6 (0.6%) were California black oak (Quercus kelloggi), and 3 (0.3%) were California bay laurel (Umbellularia californica). Although the deliveries could not be tracked by species at the Santa Cruz County yard, the species breakdown is assumed to be similar based on the inventory of hazard trees by the county in which tanoak made up about 75% of the material and coast live oak 21%.

Table 3. Breakdown of the SOD-diseased material delivered to the Marin County collection yard and the Santa Cruz County collection yard

Tree Species Marin (25 months)

Santa Cruz (18 months, 7

active)

# of Trees

Tons # of Trees

Tons

Lithocarpus densiflorus (tanoak) 817 na na na

na na

Quercus agrifolia (coast live oak) 169 na na na Quercus kelloggi (California black oak) 6 na na na Umbellularia californica (California bay laurel) 3 na na na

Total 995 915 331 Average deliveries/active month 37 47

Of the total 1,246 green tons of material collected, about 82% were processed into biomass powerplant fuel, 17% converted into firewood, and 1% processed into lumber. The commercial biomass powerplants that received the biomass fuel from this project were located in Rocklin, Woodland, and Soledad, California. All of the biomass fuel processed at the Santa Cruz County yard was sent to the Soledad facility, a total of 331.1 green tons. The Marin County yard processed 696.8 tons of biomass fuel chips that were distributed to all three of the powerplants listed above.

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Monitoring for changes in SOD infestation

Host vegetation A baseline level of SOD infestation was established before each collection yard began operations by sampling the host vegetation in and around each collection yard. The same trees were reexamined every 6 months throughout the duration of the project to determine changes in the level of the disease. Marin County – The baseline survey of P. ramorum infestation at the Marin County site in the spring of 2003 showed that 60% of the bay laurel trees in all plots were infected with P. ramorum and 11% of the coast live oak trees exhibited symptoms of the SOD disease (Table 4). After 1 year of SOD-diseased wood collection activities (spring 2004), the overall infestation level of the 102 bay laurel trees sampled decreased to 46%, but after 2 years of collection activities (spring 2005) the infestation level increased to 70%. The symptomatic coast live oak trees increased to 18% after 1 year and decreased to 7% after 2 years. The changes in infestation levels in the plots originating at the collection yards behaved very similarly to the changes observed in the control plots that were all far enough from the collection yard to not be influenced by collection and processing activities. The increase in P. ramorum infestation in 2005 may be a reflection of natural variation or it may show a trend towards increasing level of SOD. The data collected on the 27 coast live oak trees in the sample plots does not reveal a consistent trend. Although the number of symptomatic trees was gradually increasing over time the spring 2005 level dropped below the background level documented in spring 2003. Also none of the coast live oak trees advanced from symptomatic to a dead or dying condition. Spring data from a few more years is needed to fully understand the trends. The rate of infestation appeared to be greater closest to the collection yard (Figure 1); however, this was believed to be influenced more by topography than by the collection yard activities. The collection yard is located at the base of a steep slope and all of the plots closest to the collection yard are at the base of the slope. The higher percentages of infected trees at 450 feet from the collection yard were likely a reflection of higher natural P. ramorum infestations expected at the bottom of a steep slope. The observed lower infestation rates in the fall were a reflection of the difficulty in sampling infected bay laurel leaves when most of the infected leaves had fallen from the tree. None of the sentinel rhododendron plants placed in the collection yard developed positive P. ramorum cultures.

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Table 4. Survey for SOD Symptoms in Vegetation Plots Surrounding the Marin County

Collection Yard.

Spring 2003 Fall 2003 Spring 2004 Fall 2004 Spring 2005 Originating from yard

A Bay Laurel 15 8 (53%) 0 (0%) 7 (47%) 0 (0%) 12 (80%)Coast Live Oak 9 2 (22%) 3 (33%) 2 (22%) 3 (33%) 2 (22%)

B Bay Laurel 15 9 (60%) 2 (13%) 8 (53%) 0 (0%) 11 (73%)Coast Live Oak 5 1 (20%) 1 (20%) 1 (20%) 2 (40%) 0 (0%)

C Bay Laurel 31 25 (81%) 19 (61%) 22 (71%) 0 (0%) 30 (97%)Coast Live Oak 2 0 (0%) 0 (0%) 1 (50%) 2 (100%) 0 (0%)

Control (far from yard)

D Bay Laurel 36 16 (44%) 5 (14%) 6 (17%) 1 (3%) 15 (42%)Coast Live Oak 4 0 (0%) 1 (25%) 1 (25%) 0 (0%) 0 (0%)

E Bay Laurel 5 3 (60%) 2 (40%) 4 (80%) 0 (0%) 3 (60%)Coast Live Oak 7 0 (0%) 1 (14%) 0 (0%) 0 (0%) 0 (0%)

Overall Total Bay Laurel 102 61 (60%) 28 (27%) 47 (46%) 1 (1%) 71 (70 %)Coast Live Oak 27 3 (11 %) 6 (22%) 5 (18%) 7 (26%) 2 (7%)

Trees with symptoms of SOD diseaseTotal Trees

Sampled

Transect (plots) Host Species

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400 450 500 550 600 650 700 750 800 850 900 950 1000Distance from Collection Yard (feet)

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ost T

rees

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lot

Spring 2003Fall 2003Spring 2004Fall 2004Spring 2005

Spring 2003 = Baseline Infestation before opening of yard

Figure 1 – Percentage of host trees in each sample plot at the Marin County collection yard that are infected with P. ramorum.

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Santa Cruz County – Less host vegetation was available to sample at the Santa Cruz ost

imilar to the seasonal effect noted in Marin County, the Santa Cruz County data also

d

one of the sentinel rhododendrons showed signs of P. ramorum infections.

Santa Cruz

marized in Figure 2. The

active in both yards in the spring/early summer months with a secondary

Fall 2003 Spring 2004 Fall 2004 Spring 2005 Control (far from

yard)A Bay Laurel 1 0 (0%) 0 (0%) 0 (0%) 0 (0%)

Coast Live Oak 27 1 (4%) 0 (0%) 0 (0%) 1 (4%)

B Bay Laurel 28 8 (29%) 14 (50%) 9 (32%) 12 (43%)Coast Live Oak 2 0 (0%) 0 (0%) 1 (50%) 1 (50%)

C Bay Laurel 21 0 (0%) 0 (0%) 0 (0%) 5 (24%)Coast Live Oak 2 0 (0%) 0 (0%) 0 (0%) 1 (50%)

D Bay Laurel 1 0 (0%) 0 (0%) 0 (0%) 0 (0%)Coast Live Oak 12 2 (17%) 2 (17%) 2 (17%) 1 (8%)

Originating from yard

E Bay Laurel 0 n/a n/a n/a n/aCoast Live Oak 4 0 (0%) 0 (0%) 0 (0%) 1 (25%)

Overall TotalBay Laurel 51 8 (16%) 14 (27%) 9 (18%) 17 (33%)

Coast Live Oak 47 3 (6%) 2 (4%) 3 (6%) 5 (11%)

Trees with symptoms of SOD diseaseTransect Host SpeciesTotal Trees

Sampled

County collection yard site. Except for 4 small coast live oak trees near the yard all of hvegetation in the area was located more than 800 feet from the collection yard. Sshowed higher infestation levels in the spring months, but because of the smaller sample size the changes observed are not conclusive. A comparison of the data collected in Spring 2004 to the data of Spring 2005 shows very little change in the level of infestation for either the bay laurel or the coast live oaks. The biggest change observed was in control transects B anC, far from the collection activities, which had the highest population of host vegetation and were at the bottom of a steep slope. This observed increase in infestation is consistent with the hypothesis that the levels are higher at the bottom of a steep slope. N

Table 5. Survey for SOD Symptoms in Vegetation Plots Surrounding theCounty Collection Yard.

Beetle activityBark beetle activity in and around the two collection yards is sumbeetles were mostperiod of activity in the fall. This is consistent with the expected life cycle of bark beetles. The dramatic increase in bark beetle activity inside the collection yards during May and Juneof 2004 coincided with numerous deliveries of SOD-diseased hazard trees in both counties.

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The beetle counts in the other baited traps (control 1 and 2), which were located the furthest from the collection yard, were generally less than the counts inside the collection yards with a few exceptions described below. Marin County – The peak in Figure 2 showing the beetle count on August 2003 for control

at the Marin County site was in the plot farthest from the collection yard in an area with

hich are e ones most likely to be influenced by the collection yard activities, all other traps showed

rstanding

Santa Cruz County site was much lower than in arin County. This is likely a direct result of the lack of any host vegetation at this site

t

al

2many dead and dying coast live oak trees. Since this peak occurred shortly after the yard opened it is clearly a reflection of normal beetle activity in response to a significant diebackbefore the collection yard opened and not related to the collection yard activities. With the exception of the traps in or immediately adjacent to the collection yard, wtha good record of the background beetle activity in the area. As noted above, the August 2003increase in beetle activity in the Marin County control was associated with many dead and dying coast live oak trees in the area before the collection yard opened. The only other peak in beetle counts in the traps not within the yard was the October 2003 peak in the traps adjacent to the collection yard. This result was likely influenced by the beetle activity inside the yard related to the large quantity of SOD-diseased wood delivered that month. Interestingly, the extraordinary peak in beetle activity in May 2004 did not influence the traps adjacent to the yard. This cannot be explained on the basis of our current undeof beetle relationships. No evidence was found to suggest that any of the other traps wereinfluenced by the collection yard activities. Santa Cruz County – Beetle activity at the Mexhibiting advanced stages of the SOD disease. Even though P. ramorum was found in 16% of the bay laurel trees very few coast live oak trees showed SOD symptoms and those thadid were not severe. The May 2004 peak in beetle activity recorded for the traps inside the collection yard coincided with deliveries of a large quantity of dead and dying tanoak logs. There were no beetle traps adjacent to the collection yard. The peak beetle activity in the control traps occurred in the fall of 2004 and spring 2005. There was very little collection ofSOD-diseased material at these times indicating that the control traps were recording normbackground beetle activity, not in any way associated with collection yard activities. In summary, no consistent relationship was determined between the peak activity in the control traps and the delivery of SOD-diseased materials.

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03/20/03 06/28/03 10/06/03 01/14/04 04/23/04 08/01/04 11/09/04 02/17/05 05/28/05

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inside Marin Countyyard

(June 3, 2004 peak was 2352 beetles)

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03/20/03 06/28/03 10/06/03 01/14/04 04/23/04 08/01/04 11/09/04 02/17/05 05/28/05

Date

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f Bee

tles

at B

inside Santa Cruz County yard

Figure 2 – Plot of Scolytid activity at the Collection Yards (A is the Marin County yard and B is the Santa Cruz County yard.

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Monitoring of Delivered Materials The results of the monitoring activities for P. ramorum in the host material delivered to and processed at the collection and processing yards are presented in Table 6. P. ramorum has been cultured from the following specimens:

• 2 of 8 bay leaf samples recovered from the chip bin in the collection yard • 2 of 87 samples of chips from the collection bins • 16 of 165 pieces of freshly split firewood • 1 of 306 pieces of firewood dried for about 6 months • 2 of 161 air-borne dust samples collected near processing equipment • 9 of 88 specimens of grinder and saw dust collected next to the wood grinders and

sawmill • 7 of 16 rainwater run off specimens

None of the samples collected from the sentinel rhododendron plants tested positive for P. ramorum.

Table 6. P. ramorum monitoring of SOD-Diseased Material Delivered or Processed at all Collection and Processing Yards.

Sample Size

P. ramorum positive

Sample Size

P. ramorum positive

Sample Size

P. ramorum positive

Sample Size

P. ramorum positive

Delivered Chips 63 1 (1%) 24 1 (4%)

Delivered bay laurel leaves 8 2 (25%)

Airborne dust 143 2 (1%) 6 0 (0%) 12 0 (0%)

Rainwater 16 7 (44%)

Fresh firewood 118 16 (14%) 47 0 (0%)

Air-dried firewood 290 1 (0.3%) 16 0 (0%)

Grinder fines 12 0 (0%)Air-borne Grinder/ sawdust

49 8 (16%) 15 1 (7%) 24 0 (0%)

Sentinel rhododendrons 15 0 (0%) 4 0 (0%) 2 0 (0%) 12 0 (0%)

Total 714 37 (5%) 43 2 (5%) 95 0 (0%) 24 0 (0%)

Overall Total 876 39 (4.5%)

Specimen Type

Powerplant Sawmill Santa Cruz C. Yard Marin C. Yard

The results were similar in both counties, but for the Santa Cruz County collection yard the smaller sample sizes made the results harder to interpret. For this reason the following discussion is focused on Marin County.

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Delivered Materials – P. ramorum was detected in all forms of the material delivered to the Marin County collection yard. Out of the 63 samples collected from the material delivered in chip form, only 1 tested positive for P. ramorum. Bay leaves were rarely found in the delivered materials because the majority of the host trees handled by tree service companies are dead and dying oaks. When bay leaves were found they were sampled and of the 8 bay leaves collected, only 2 tested positive. Although this low number of positives may at first suggest a low incidence of SOD-disease in the material delivered it is more a reflection of the difficulty in sampling the material. When a tree is removed from a location the branches and leaves are put through a chipper and blown into a truck. The zones of infestation in woody materials are small when considering the total volume of the tree. The zones infested with P. ramorum are mixed with larger volume of material not infested from the same tree. This in effect serves to dilute the concentration of P. ramorum in a pile of chips (the needle in the haystack syndrome). As a result the chance of collecting a sample with active P. ramorum from a pile of chips is very low. A similar dilution effect occurs in the airborne dust generated in the yard when the materials are delivered or moved around in the yard. The likelihood of capturing viable spores or hyphae fragments of P. ramorum is very low. However 2 of 118 dust samples collected in water buckets did produce positive P. ramorum results when pear-baited. The results from the rainwater runoff samples are probably a better measure of presence of P. ramorum in the delivered materials. These samples were collected during rainstorms from the water that seeped through and ran off of the exposed piles of chips. If P. ramorum is present in the pile it is highly likely that it will be transported with the rainwater. Thus it is not surprising that 44% of the rainwater samples tested positive, the highest proportion of all samples. Processing and Processed Materials – Samples were collected from all aspects of processing and from the processed materials and final products. The highest percentage of P. ramorum positive samples in processing was obtained from the freshly split firewood. For this test, 118 pieces of freshly split firewood exhibiting SOD symptoms were selected for the pear-baiting procedure. Of these 16 resulted in positive cultures of P. ramorum. Considering the difficulty of harvesting active spores from solid wood this result suggests that precautions should be considered when processing and marketing firewood from SOD-diseased trees. The long-term viability of P. ramorum in firewood is not known but it was surprising that 1 positive culture was obtained from the 290 firewood specimens that had air-dried for 6 months or longer. The viability of P. ramorum in firewood is being studied in more detail in a follow-up project. Positive results were also obtained from water buckets used to collect airborne dust generated from wood grinding machines (hammermills and tubgrinders) that process solid wood into biomass fuel. Of the 49 specimens collected at the Marin County yard during grinding, 8 produced positive cultures when pear-baited. The higher percentage of positives obtained next to the grinder than found in the airborne dust in the yard is understandable because the grinder operates under a fine water mist environment to help settle the airborne dust.

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Seasonal Effects – When the number of positive P. ramorum specimens collected is plotted with respect to the time of year it was collected it becomes clear that the majority of the positive specimens was gathered in the wet rainy months from January to April, with the peak in March, typically a warm and wet month (Figure 3). The part of California where these collection yards were located rarely gets any rain during the period from May to October and most of the rain typically occurs in December, January, and February. The higher incidence of positive samples during these months suggests a high correlation between P. ramorum activity and the wet winter months. This suggests that the risk of spreading the disease through processing activities is much higher during the wet-rainy winter season.

Figure 3. Frequency of Positive Phytophthora ramorum Specimens With Respect to the Month of the Year the Specimen was Collected.

02468

10121416

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month when Sample was Collected

Num

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ples

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Analysis of Wood properties and lumber quality

Wood Properties Basic wood properties were measured for coast live oak and tanoak, the two SOD host tree species most often removed from the landscape (Table 7). In addition to determining the specific gravity and major chemical constituents for both species, a detailed sugar analysis was also performed on coast live oak to determine if SOD-diseased wood was suitable as a feedstock for ethanol production.

Table 7. Basic Wood Properties of Quercus agrifolia (coast live oak), and Lithocarpus densiflorus (tanoak).

Property Coast Live Oak logs, Northern Marin County

Coast Live Oak logs, Southern Marin County

Tanoak logs Santa Cruz

County

Tanoak lumber Santa Cruz

CountySpecific Gravity

(od mass, grn vol. basis) 0.641 0.686 0.584 0.555Heat of Combustion 8448 Btu/lb Chemical Constituents

Cellulose + Hemicellulose 61.8% 59.8% 60.1% Sugar Analysis (monoscharrides)

Glucose 31.6% 30.9%Xylose 12.5% 12.1%

Galactose 0.9% 0.9%Arabinose 1.6% 1.9%Mannose 0.7% 0.9%

Lignin 23.2% 21.9% 26.9% Extractives 13.4% 16.8% 13.0%

Ash 1.6% ~1.5% 0.9% Both are high-density species; coast live oak with an average specific gravity of about 0.66, tanoak with a specific gravity of 0.57. The tanoak heat of combustion value of 8448 Btu/lb reported above is within the generally reported range of heating values for most high-density hardwoods. These basic properties are consistent with the properties expected from high-density hardwoods and the results do not preclude the use of this material for any fiber-based or chemical product. For example, the SOD-diseased wood can be expected to perform adequately as a biomass powerplant fuel, or a feedstock for hardwood pulp or ethanol production. The acceptability of using the SOD-diseased trees for higher value solid wood products that require the trees to be converted into lumber will depend on the effect the disease has on lumber quality.

17

Lumber Quality Twenty-four logs (15.5 tons total weight) of SOD-diseased logs were selected for sawlog potential at the Santa Cruz collection yard and delivered to the sawmill in Davenport, CA. The species mix for the sawlog test was 21 tanoak logs, 2 coast live oak logs, and 1 California black oak log. The yield and physical properties of the logs and lumber produced is summarized below in Table 8. The average moisture content of the heartwood and sapwood lumber was 84% and 74% respectively. The specific gravity (oven dry mass/green volume) of the tanoak processed was 0.57. The logs were processed into 8-foot long lumber measuring 5/4-inch thick and various widths of 3-inch, 4-inch, and 6-1/4 inch. The entire amount of solid wood residue from the sawmilling operation was processed into firewood and the sawdust was collected and stored on site for future analysis and potential utilization. The total log volume of 412.84 ft3 (4,954 board feet) produced 188.89 ft3 (2,393 board feet) of green, 5/4-inch thick lumber or a lumber yield of 48%. The remaining 52% percent of the log volume not converted into lumber was either sawdust or a solid wood residue that was converted to firewood.

Table 8– Green lumber yield and wood properties of test sawlogs by species and log quality

Species Log

Quality Number of logs

Avg. MC (%)

Avg. SG Avg. Diameter (in)

Green Lumber Vol.

(bd. ft.)

Yield (%)

Tanoak Good 9 92.1 0.55 19.5 103.1 47.0 Tanoak Moderate 8 81.2 0.60 17.7 87.9 50.5 Tanoak Low 3 76.0 0.60 21.9 113.4 45.2 Coast live oak Good 3 75.3 0.70 20.8 102.8 43.7 CA black oak Good 1 90.6 0.56 17.9 98.0 56.5

Overall Average

24 84.8 0.57 19.3 99.7 47.8

The logs were evaluated for quality on the basis of log form (straightness and taper), presence and level of decay, level of beetle infestation, and the presence of heart stain (known to be highly correlated with drying defects). The lumber yield varied from 45.2% to 50.5% but this variation was not correlated with log quality, the moderate category resulted in the highest yield. Similarly, no trend was identified between lumber yield and log diameter (Figure 4), moisture content, or specific gravity. The yield with these factors resulted in plots similar to Figure 4.

18

Figure 4. Green Lumber Yield by Log Diameter

0.0%10.0%20.0%30.0%40.0%50.0%60.0%70.0%80.0%90.0%

100.0%

0.0 5.0 10.0 15.0 20.0 25.0 30.0

log diameter (inch)

Kiln-Dried Lumber – The yield of green lumber only tells half of the story of lumber quality. The condition of the lumber after it has dried is a very important quality parameter as many defects often develop during drying, especially in high-density hardwoods. These drying defects often dramatically reduce the quality and value of the lumber. The green lumber produced from the SOD-diseased logs discussed above was dried following generally accepted guidelines for drying tanoak and other high-density hardwoods (Shelly, Jackovics 2001). The green lumber was air-dried for 6 months to a moisture content of about 30% and then dried to a final moisture content of 8% in lumber dry kiln. After drying the lumber was surfaced on 2 sides (S2S) to a board thickness of 7/8-inch and then sorted into grade categories based on the size and quantity of defects. The grade categories used were roughly based on the National Hardwood Lumber Association (NHLA) hardwood lumber grading specifications and were defined from the highest quality to lowest quality as:

1. High Grade – at least 95% of the surface free of defects with slight color variation allowed – (NHLA No. 1 Common or Better)

2. Moderate Grade – at least 80% of the surface free of defects with moderate color variation allowed – (NHLA No. 2 Common)

3. Low Grade because of warp and/or collapse – (NHLA No. 3 Common) 4. Low Grade because of beetle damage or spalting – (NHLA No. 3 Common) 5. Cull – below grade, best use is firewood.

Lumber yield dropped to 34.5% of the green log volume. The majority (62%) of the kiln-dried lumber produced was low or below grade; 17% because of warp and/or collapse, 39% because of beetle damage or spalting (incipient decay), and 6% cull (Table 9). The excessive degrade caused by the beetle damage and incipient decay (39%) makes the profitable conversion of SOD-diseased logs into lumber very unlikely as illustrated in Table 10.

Yiel

d (%

)

19

Table 9. Volume of Wood in Sample Logs and the Volume of Green and Kiln Dried

Lumber Produced.

e conservative estimated cost to process the 413 ft3 of logs into 152 ft3 (1,800 board feet)

able 10. Estimated Wholesale Value of Lumber Produced from Sample Logs.

ensified fuel in the form of firelogs was processed from 2 tons of SOD-diseased wood mercial firelog facility. Five separate runs were

dstocks varying the proportion of tanoak mixed with lower density

% tanoak to 40% softwood

Log Green lumber

Grade Lumber

High Grade n/a n/a 16.33 11%Moderate Grade n/a n/a 41.34 27%Low Grade because of warp and/or collapse n/a n/a 25.32 17%Low Grade because of beetle damage and/or spalting n/a n/a 59.35 39%Cull (below grade) n/a n/a 9.30 6%

Total 412.8 188.9 151.60 142.34

Grade Category

Volume (ft3)

Kiln-Dried Lumber

Thof surfaced, kiln-dried lumber is $1,535 based on a 2 person small sawmill sawing for 20 hours at $15 per hour, a kiln drying cost of $200/thousand board feet, and a milling cost of $250/ thousand board feet. Clearly a business cannot survive if it costs $1,535 to produce products valued at $1,518; a loss of $17. For lumber to be an economically viable product from SOD-diseased logs it will be necessary to find higher value markets for the lumber. Niche marketing of the lumber direct to woodworkers could dramatically increase the valueof the lumber but past experiences in developing niche markets for wood products are populated by many failures. A detailed analysis of the market potential is needed before sucha venture can be recommended.

T

Grade Category Volume (ft3) Value ($ / ft3) Total Value

High Grade 16.33 13.54 $221Moderate Grade 41.34 12.28 $508Low Grade because of warp and/or collapse 25.32 9.1 $230Low Grade because of beetle damage and/or spalting 59.35 9.1 $540Cull (below grade) 9.30 2 $19

Total 151.60 $1,518

Densified Fuel Dresidues (sawdust and chips) at a comperformed with feesoftwood, that is:

• Run 1 = 20% tanoak to 80% softwood • Run 2 = 40% tanoak to 60% softwood • Run 3 = 60• Run 4 = 80% tanoak to 20% softwood • Run 5 = 100% tanoak, no softwood

20

Dur g er surface of the extrusion die and the surface of t e les were selected from each run to measure the ore temperature of the firelog as it emerged from the die and the density of the firelogs

eratures (Figure 4). The exterior surface of the die averaged about 52 C and the surface f the firelog averaged about 100oC. The core temperature of the firelogs ranged from 64oC

r emerging

irel typical feedstock of dry manufacturing softwood wroduced from the various tanoak feedstocks ranged

in each test run the temperature of the outhe xtruded firelog were measured. Samp

cproduced in each run. Core temperatures of 4 runs were recorded (A, B, C, and D in Figure 5).

Process Temperatures – The firelogs of each run were produced at very similar temp o

oto 92oC and the average core temperature remained about 60oC for 10 minutes aftefrom the extrusion machine. This means that all of the wood in the firelog was heated to temperatures approaching or above what is considered a lethal temperature for P. ramorum.

Figure 5. Run Temperatures of Firelogs Produced in a Heated Extrusion Die.

F og Quality – The firelogs produced were hardeap6). Firelogs at this density do not perform as well in with further experimentation with feedstock mixes anfeed-speed, and extrusion pressure an acceptable fire

0.0

20.0

40.0

60.0

80.0

100.0

0 1 2 3

Run Time (min

Tem

pera

ture

(C)

Core Temp A

g120.0

4

21

surface of firelo

Temp D

Core Temp C

Core

Core Temp B

e
exterior surface of di
aste (about 1.0 g/cm3). The firelogs from 1.08 g/cm3 to 1.23 g/cm3 (Figure

re,

r and denser than firelogs produced with

free combustion but it is believed that d the process variables of temperatu

log can be produced.

6 7

utes)

5

Figure 6. Density of Firelogs Produced with Varying Proportions of Tanoak.

1.05

1.1

1.15

1.2

1.25

0 1 2 3 4 5 6

Run Time (minutes)

Den

sity

(g/c

m3 )

20% Tanoak40% Tanoak60% Tanoak80% Tanoak100% Tanoak

Discussion The two collection yards managed under this project successfully provided central locations for the collection, sorting, and diversion of SOD-diseased wood to acceptable uses. The Marin County collection yard was the most active, with the support of 14 tree service companies and the county of Marin. The Santa Cruz collection yard was very active during the Santa Cruz County hazard tree removal project but it was less successful at attracting local tree service companies to participate in the program. These yards have collected about 1,250 green tons of woody biomass from Sudden Oak Death Disease host trees, mostly tanoak (~ 80%) and coast live oak (~ 19 %). The potential for this material having viable P. ramorum spores is higher than in the general population of host material because the yards only accepted material that exhibited multiple symptoms associated with the disease. However, since the presence of P. ramorum was not positively identified in each tree the yards undoubtedly accepted some dead and dying trees that were SOD-disease free. The high correlation between the deliveries of host woody biomass to the yards and the scolytid beetle count inside the collection yard suggests that even though the beetles may not be a vector for P. ramorum, they are highly associated with the SOD-diseased wood. Because most of the wood delivered was from hazard trees that were dead for more than 4 months, it is suggested that the beetles were not attracted to the wood once in was in the yard but rather they came into the yard in the dead wood. Also, the beetles did not appear to spread far from the collection yard since the beetle counts in the traps away from the yard did not show a corresponding rise. Although the relationship between massive beetle attack and tree death is not fully understood, this evidence of large numbers of beetles associated with the wood collected suggests that the beetles play an important role in the disease and further study is needed.

22

The data gathered from the collection yard activities and the periodic sampling for P. ramorum in and around the collection yard will be used in future studies to analyze the risk of spreading Sudden Oak Death disease by transporting and processing biomass and wood products. Although P. ramorum was found in 39 of the 864 specimens collected (~ 4%), all of the positive cultures, except for firewood, were collected from unprocessed material at the collection yard or at the primary processing equipment (grinders and saws). Although no positive cultures have been obtained at the end uses of biomass powerplant fuel, firewood air-dried longer than 6 months, or in processed lumber, the 16 positive cultures collected from the fresh split firewood and the 1 positive from the partially air dried firewood emphasize the need to further study the survivability of P. ramorum in processed firewood. It is encouraging that none of the firewood specimens dried longer than 6 months tested positive. Also of interest is the observation that about 2/3rds of the positive P. ramorum cultures were collected during the winter and early spring months, typically the rainy months. This data suggests that P. ramorum sporulation is most active during the wet weather season of the year and that the risk of spreading P. ramorum is higher during these months. The evaluation of the lumber potential of SOD-diseased logs revealed that the lumber produced was much lower in quality than expected from tanoak logs. However some preliminary observations are possible. The wood properties, including an average specific gravity of 0.57 and an average green moisture content (MC) of 85%, although slightly lower than the previously reported values of 0.60 specific gravity and 90% MC, were within the range of expected normal variation (Shelly and Jackovics 2001). However the 48% yield of green lumber reported in this study is markedly lower than the 60% green lumber conversion previously reported by Shelly and Jackovics (2001) for tanoak. The yield of acceptable lumber after kiln drying decreased further to 34% of the original log volume. The extra deterioration of wood quality from the decay and insect infestations in the logs accounts for this lower yield. Although lumber can be produced from SOD-diseased trees, the low yield of high quality lumber limits the economic potential.

Summary The data reported in this study indicate that viable P. ramorum spores can be collected from Sudden Oak Death diseased host trees that are delivered to collection yards. However, no evidence has been gathered to support the hypothesis that the collection, sorting, and processing activities in the collection yards influences SOD disease infestation levels at or near the sites. From the wood property point of view, biomass powerplant fuel, firewood, and densified fuel products (firelogs and pellets), and a feedstock for pulp or organic chemicals are considered good uses for SOD-diseased wood. Lumber products can be made but the biodeterioration of the wood in the outer sapwood of diseased logs limits the opportunities of establishing an economically viable venture. From the disease-spread point of view the evidence collected in this project suggest that the risk of spreading SOD disease during processing is quite low but because P. ramorum was

23

collected during processing caution is recommended when processing activities generate wood/bark dust or freshly processed material is exposed to rain. Both dust from processing equipment and rainwater runoff were identified as sources of positive P. ramorum cultures. Firewood may be a good use but more information is needed to understand the survivability of P. ramorum in firewood. The relative ranking of these options as a best use is dependent on the expected value of the product and any extra costs associated with handling the material to limit the risk of spreading SOD. This economic potential will be evaluated in future work. Project Highlights

• A total of 1,246 tons of potentially SOD-diseased material was processed through the 2 yards facilitating the proper disposal of SOD-diseased wood in Marin and Santa Cruz counties and complementing their hazard tree removal programs. Tanoak made up about 80% of material received and about 19% was coast live oak. Other host tree species contributed the remaining 1%.

• A toll free number, website and information pamphlets prepared by the project team contributed to the public outreach effort concerning sudden oak death disease awareness.

• 82% of material received was utilized as biomass powerplant fuel, 17% was converted into firewood and 1% into lumber.

• No consistent increase in the infection levels of P. ramorum or associated beetle population around the collection yards was apparent when compared to baseline levels before the opening of yards. Longer term monitoring data is needed to be conclusive.

o At the Marin County site, the infection level in the bay laurel monitoring plots showed an overall 10% increase from spring 2003 to 2005 but almost no change in the health of the coast live oaks in the plots.

o At the Santa Cruz site there was an increase in both bay laurel and coast live oak infection levels from Spring 2004 to 2005 but the small sample size of host plants and the distance from the collection yard activities to the sample plots suggests the changes observed are part of the normal variation of disease activity.

o Sentinel rhododendrons remained P. ramorum free during the length of the project

• P. ramorum was confirmed in the material delivered to the collection yards, but not consistently.

o The smaller than expected number of P. ramorum positive specimens obtained from chipped materials delivered to yard is likely a result of the dilution effect of a small amount of infested wood in a large pile of chips.

o The high number of P. ramorum positive specimens collected from the samples of rainwater run off from chip piles and bins confirmed the presence of P. ramorum in the delivered material and indicates that the method of collecting water that seeps through piles of chips is a better method of sampling potentially infested chip piles than collecting handfuls of chips from the piles.

24

o Positive P. ramorum samples were obtained from freshly split firewood. • P. ramorum was found in dust generated from wood grinding equipment. • P. ramorum was found in 1 partially air-dried firewood specimen. Additional testing

is underway to determine the importance of this observation. • Most of the specimens that tested positives were collected during the rainy season

with the most collected in the month of March, the month with both warm ambient temperatures and high precipitation.

• Chemical analyses of SOD-diseased wood indicate no noticeable degradation in chemical properties. Levels of polysaccharides remain high suggesting this material was acceptable for pulp or organic chemicals such as ethanol. The heat of combustion (measure of energy value) was within the expected range for hardwoods.

• Overall specific gravity of the wood from SOD-diseased trees was within the expected range for the species

• Biodeterioration of sapwood by beetles and secondary wood decay organisms decreased the quality of lumber produced from SOD-diseased trees suggesting lumber production to be uneconomical.

• SOD-diseased wood successfully produced densified firelogs and the wood was subjected to temperatures in the extrusion process high enough to be considered lethal to P. ramorum.

25

References Davidson, J. M.; Rizzo D. M.; Garbelotto M. 2002. Phytophthora ramorum and sudden oak death in California: II. Pathogen transmission and survival. In: Standiford R, McCreary D, Purcell K.B. (eds). Proc. 5th Oak Symposium: Oaks in California’s Changing Landscape. Oct. 22-25, 2001. San Diego, CA. Gen. Tech. Rpt. PSW-GTR-184. USDA Forest Service, Pacific Southwest Research Station, Albany, CA.; 741-749 Erwin, D. C.; Ribeiro, O.K. 1996. Phytophthora Diseases Worldwide. St. Paul, MN: APS Press. 562 p. Furniss, R. L.; Carolin, V. M. 1977. Western Forest Insects. Miscellaneous Publication No. 1339. Washington, DC: US Forest Service, Department of Agriculture; 654 p. Garbelotto M. 2003. Composting as a control for sudden oak death disease. BioCycle: February 2003; 53 - 56. Shelly, J. R.; Jackovics, K. 2001. Tanoak Utilization: Coordination of Tanoak Recovery and Yield Studies and Knowledge Transfer. University of California Forest Products Laboratory. Berkeley, CA. Technical Report Number 35.01.4xx. September 2001. 29 p. Shelly, J. R.; Singh, R.; Langford, C.; Mason, T. 2003a. Removal and utilization of high risk sudden oak death host material. Progress Report 1. Internal Report, January 17, 2003. University of California Forest Products Laboratory, Richmond Field Station, Richmond, CA. 13 p. Shelly, J. R.; Singh, R.; Langford, C.; Mason, T. 2003b. Removal and utilization of high risk sudden oak death host material. Progress Report 2. Internal Report, July 25, 2003. University of California Wood Resources Group, Richmond Field Station, Richmond, CA. 59 p. Shelly, J. R.; Singh, R.; Langford, C.; Mason, T. 2004a. Removal and utilization of high risk sudden oak death host material. Progress Report 3. Internal Report, January 29, 2004. University of California Wood Resources Group, Richmond Field Station, Richmond, CA. 65 p. Shelly, J. R.; Singh, R.; Langford, C.; Mason, T. 2004b. Removal and utilization of high risk sudden oak death host material. Progress Report 4. Internal Report, July 30, 2004. University of California Wood Resources Group, Richmond Field Station, Richmond, CA. 46 p. Shelly, J. R.; Singh, R.; Langford, C.; Mason, T. 2005a. Removal and utilization of high risk sudden oak death host material. Progress Report 5. Internal Report, February 1, 2005. University of California Wood Resources Group, Richmond Field Station, Richmond, CA. 27 p.

26

Shelly, J. R.; Singh, R.; Langford, C.; Mason, T. 2005b. Understanding the Disposal and Utilization Options for Sudden Oak Death-Diseased Wood. Proceedings of Sudden Oak Death Second Science Symposium, Monterey, California, January 2005. USDA Forest Service General Technical Report PSW-GTR-xxx. (in press). Storer, A. J.; Keirnan K. E.; Palkovsky, N. K.; Hagen, B. W.; Slaughter, G. W.; Kelly, N. M.; Svihra P. 2001. Sudden Oak Death: Diagnosis and management. Pest Alert #5. March 2001. University of California Cooperative Extension, Marin County, Novato, CA. 12 p.

27

Acknowledgments This project could not have been successfully implemented and managed without the assistance cooperation of the many individuals on the project Coordinating Committee (complete list posted at http://groups.ucanr.org/SODBusters) representing the California Department of Forestry, California Waste Management Board, California Department of Food and Agriculture, and the Marin County and Santa Cruz County Agricultural Commissioners Offices. A special thanks to Don Gasser, Pacific Gas and Electric Company for spearheading the early discussions of the disposal and utilization of SOD-diseased wood; Cynthia Murray, Marin County Supervisor for her early support of the project; Joe Garbarino and John Oranje, CEO and Vice President of the Marin Resource and Recovery Center; Patrick Mathews, Santa Cruz Department of Public Works and Mitch Matsumoto of Vision Recycling, Inc. for there help in operating the collection yards; Cheryl Blomquist, California Department of Food and Agriculture for her assistance in the DNA identification of P. ramorum cultures; Don Owen, California Department of Forestry for his assistance with the interpretation of bark beetle activity; and last but certainly not least, the California Oak Mortality Task Force staff members Janice Alexander, Karl Buermeyer, and Kati Palmieri (Facino) for their assistance in public outreach, training, and information dissemination. This project was funded by the California Department of Forestry Agreement No. 8CA01257 with assistance from the USDA Forest Service-Region 5, State and Private Forestry.

28

Appendix I – Progress Updates Covering January to June 2005 During this reporting period, the following 5 monthly “Progress Updates” describing the activities at each collection yard were prepared and distributed by the project partner TSS Consultants.

Progress Update 25 - Jan. 12, 2005 Progress Update 26 - Feb. 11, 2005 Progress Update 27 - March 17, 2005 Progress Update 28 - April 24, 2005 Progress Update 29 - May 2, 2005 Progress Update 30 - June 14, 2005 (Final Update)

Each progress update is presented on the following pages:

29

Date: Jan. 12, 2005 Report Period: DecemberPrepared By: Tad Mason, Project Activities:

December 15 - Assleaf samples from boak trees. Gathered December 15 – Met

processing and stora December 17 – Con

oak logs now stockpof SOD hazard tree considering the use any firewood that m December 17 – Con

Watsonville. Plans adiscuss utilization o December 20 – SOD

presentations/poster December 22 – Con

Works regarding theCounty. Carolyn noround of SOD tree rwith this new roundSODBusters collect

Challenges: No deliveriesDecember. Opportunities: Some addiremovals) for SOD hazard up in February and March (Highlights of Projected A Continue to encourag

SODBusters project. Monitor deliveries an Attend SOD Confere

Fac

Funding by the Cal

SODBusters Project http://groups.ucanr.org/SODBusters

University of California Cooperative Extension

SODBusters Project Hotline: 1-866-SOD-7411 (1-866-763-7411)

John Shelly Principal Investigator Tad Mason, Project Coordinator UC Richmond Field Station, Bldg 478 TSS Consultants 1301 South 46th Street 2724 Kilgore Road Richmond, CA 94804-4698 Rancho Cordova, CA 95670 Telephone: 510.231-9419 Telephone: 916.638.8811 Ext. 112 Fax: 510.231-9427 Fax: 916.638.9326

[email protected] [email protected]

SODBusters Project Update # 25

1, 2004 through December 31, 2004 SODBusters Project Coordinator

isted with the gathering of vegetation samples at the Marin collection yard. Gathered ay trees on all five research transects. Noted any changes in symptoms on coast live insect samples from the funnel traps. with Joe Garbarino, President, Marin Resource Recovery to review firewood ge procedures. tacted staff at Pfeiffer/Big Sur State Park to confirm their management plans for tan iled on site at the park. These trees were removed and the logs stockpiled as a result removals over the past 5 – 8 years. Park staff noted that they are currently of these logs as traffic barriers. I confirmed with staff that we would like to sample ight be processed from these logs. tacted Summit Views to arrange a meeting at their densified firewood operation in re to meet them on 1/20 (in conjunction with the SOD Conference at Monterey) to f SOD material as feedstock for their operation. Busters Implementation Team meeting to review project progress and coordinate

s for the upcoming SOD Conference sponsored by COMTF. tacted Carolyn Banti, Assistant Civil Engineer, Santa Cruz County Dept of Public next round of funding available for SOD hazard tree removals in Santa Cruz

ted that an additional $50,000 is available now and this will help to fund another emovals. She estimates that between 80 and 150 additional trees will be removed of funding. Much of the material from these removals may be delivered to the ion yard at Ben Lomond. of SOD material were made to the Santa Cruz collection yard during the month of

tional funding (left over from counties that did not utilize funds set aside for tree tree removals is now available for Santa Cruz County and tree removals should start see above). ctivities in the next thirty days: e Santa Cruz area tree service companies/tree care professionals to participate in the

d activities at both collection yards. nce at Monterey.

ilitating the disposal and utilization of Sudden Oak Death infected wood. ifornia Department of Forestry and Fire Protection and Region 5, USDA Forest Service.

30

http://groups.ucanr.org/SODBusters

Date: Feb. 11, 2005 Report Period: January 1, 20Prepared By: Tad Mason, SOProject Activities:

January 7 - Arranged fprocessed and dust/fin January 11 – Assisted

Monterey. Poster high January 19- Arranged

that was stored on the January 18 – 21 Atten January 20 – Met with

Toured operation to beprocessing of SOD ma January 20 – Generate

work defining their pa January 28 – Contacte

funding available for SCommunity Tree Servthem know that the Saas a result of the tree r

Challenges: No deliveries ofDecember. Opportunities: Community to the Santa Cruz collection yHighlights of Projected Acti Continue to encourage S

SODBusters project. Monitor deliveries and a Assist in the preparation Prepare for SODBusters

FacilitFunding by the Califor







05 through January 31, 2005 DBusters Project Coordinator

or processing of SOD chip material at the Marin collection yard. Material was es sampled. Processed biomass fuel sent to Woodland with the preparation of a poster and paper presentation for the SOD Symposium at lighted SOD material used as firewood. for processing of SOD logs and rounds at the Marin collection yard into firewood hill above the collection yard – for future sampling and monitoring. ded the SOD Symposium at Monterey. Summit Views at their Good Wood fuel log processing operation at Watsonville. tter understand the operation’s capacity and to work out an agreement to test the terial into densified fuel logs d draft sanitary procedures for Summit Views to consider as part of a scope of rticipation in a research project. d Santa Cruz County Dept of Public Works regarding the Phase III round of OD hazard tree removals in Santa Cruz County. Followed up by contacting

ices of Watsonville, the contractor of choice to remove the hazard trees, to let nta Cruz Collection Yard is open and available to receive SOD material generated emovals. Provided transport certificate, and related information. SOD material were made to the Santa Cruz collection yard during the month of

Tree Service of Watsonville has expressed an interest in providing SOD material ard. vities in the next thirty days: anta Cruz area tree service companies/tree care professionals to participate in the

ctivities at both collection yards. of SODBusters Progress Report #5. Coordinating Committee Meeting in March at the UC Richmond Field Station.

ating the disposal and utilization of Sudden Oak Death infected wood. nia Department of Forestry and Fire Protection and Region 5, USDA Forest Service.

31


Date: March 14, 2005 Report Period: February 1, 200Prepared By: Tad Mason, SODProject Activities:

February 3 – Contacted Sservices and to let them kcollection yard due to SO February 9 – Sent out m

meeting. Meeting will be February 12 – Met with M

SOD material at the Mar February 18 – Contacted

densified fire logs at theiSODBuster operations as February 22 - Arranged February 25 – Contacted

Watsonville fire log oper Explore funding opportu

Recovery

Challenges: No deliveries of SOFebruary.

Opportunities: Summit Views for their densified fire log opera

Highlights of Projected Activit Continue to encourage San

SODBusters project. Monitor deliveries and act Assist in the preparation o Prepare for SODBusters C

FacilitatinFunding by the California







5 through February 28, 2005 Busters Project Coordinator

anta Cruz County and Vision Recycling to confirm status of their invoices for now that more SOD material may be delivered to the Santa Cruz SODBusters D hazard tree removals sponsored administered by Santa Cruz County.

eeting notice and agenda for March 21 SODBusters Coordinating Committee from 10am to 2pm at the UC Richmond Field Station.

arin Resource Recovery owner to review operation and discuss processing of in collection yard. Summit Views LLC to review draft Scope of Work for the processing of r Watsonville operation. Hope to conduct a test using SOD material from feedstock in the manufacture of densified fire logs. for the processing of SOD material at the Marin collection yard. Summit Views regarding budget for the Scope of Work regarding a test at their ation. nities for biomass to energy conversion technologies at Marin Resource and

D material were made to the Santa Cruz collection yard during the month of

LLC is interested in participating in the testing of SOD material as feedstock tion at Watsonville.

ies in the next thirty days: ta Cruz area tree service companies/tree care professionals to participate in the

ivities at both collection yards. f SODBusters Progress Report #5. oordinating Committee Meeting March 21at the UC Richmond Field Station.

g the disposal and utilization of Sudden Oak Death infected wood. Department of Forestry and Fire Protection and Region 5, USDA Forest Service.

32








Date: April 10, 2005 Report Period: March 1, 2005 through March 31, 2005 Prepared By: Tad Mason, SODBusters Project Coordinator Project Activities:

March 7 – Contacted Community Tree Service of Watsonville to confirm their plans to deliver SOD material into the Santa Cruz collection yard. CTS is under contract to Santa Cruz County for the removal SOD hazard trees. March 9 – Alerted staff at the Ben Lomond transfer station that Community Tree Service should begin

delivering SOD material to the collection yard. March 14 – Contacted Marin Resource Recovery staff regarding Rutgers University film crew that

would like to film activities at the Marin collection yard. March 15 – Prepared for SODBusters Coordinating Committee meeting. Sent out reminders to

committee members. Contacted Mountain West Communications regarding phone traffic accessing the SOD Info line. Provided input/editing for Project Review # 5. March 21 – Coordinating Committee meeting at Richmond Field Station. March 31 – Contacted Vision Recycling to arrange for processing of SOD material at the Santa Cruz

collection yard. March 31 – Progress Report 5 posted on the web site.

http://ucce.ucdavis.edu/freeform/SODBusters/documents/Progress_Reports6646.pdf

Challenges: Vision Recycling has experienced some turnover in management staff. Opportunities: Santa Cruz collection yard received deliveries of SOD material as a result of additional COMTF funding being available to the county for the removal of SOD hazard trees. Highlights of Projected Activities in the next thirty days: Monitor deliveries and activities at both collection yards. Prepare to close down the collection yards as the SODBusters project comes to a close. The yards will be

stop receiving SOD material on June 15 with the yards completely closed by June 30. Prepare to conduct final vegetation and insect sampling at the collection yards.

Documents Attached: Meeting notes from the March 21, Coordinating Committee

Facilitating the disposal and utilization of Sudden Oak Death infected wood. Funding by the California Department of Forestry and Fire Protection and Region 5, USDA Forest Service.

33








Date: May 2, 2005 Report Period: April 1, 2005 through April 30, 2005 Prepared By: Tad Mason, SODBusters Project Coordinator The 2-1/2 year Sudden Oak Death Utilization project is coming to a close. Enough SOD material has been delivered to the SODBusters collection yards at Marin County and Santa Cruz County for the implementation team to complete research in support of the project goals, which are: “To evaluate the utilization potential of host tree species, identify best and most appropriate uses, and develop protocols for handling Phytophthora ramorum infected materials” Plans are now underway to scale back operations at both collection yards. June 17, 2005 is the last day that SOD material will be accepted at either collection yard. Project Activities:

April 7 – Contacted Vision Recycling to coordinate processing of SOD material stored at the Santa Cruz collection yard. April 8 – Contacted Soledad Energy to confirm that biomass fuel from the Santa Cruz collection yard

will be delivered to SE on April 13. April 13 – SOD material stored at the Santa Cruz collection yard is processed. Most of the biomass

material generated is hauled to Soledad Energy for use in power generation. Approximately 2 tons of material is stored on site for future utilization in the manufacturing of densified fuel logs (“Good Wood” operation at Watsonville, CA). April 25 – Sent notice to Marin Resource Recovery regarding the coordinated shutdown of the Marin

collection yard. April 27 – Sent notice to Santa Cruz County regarding the coordinated shutdown of the Santa Cruz

collection yard. April 29 – Arranged for the pick up and delivery of processed SOD material, from the Santa Cruz

collection yard to the “Out of the Woods” facility at Bonny Doon. “Out of the Woods” staff will blend this material with SOD-diseased sawmill residue for delivery to “Good Wood” operation.

Challenges: None Opportunities: None Highlights of Projected Activities in the next thirty days: Monitor deliveries and activities at both collection yards. Prepare to close down the collection yards as the SODBusters project comes to a close. Conduct final vegetation and insect sampling at the collection yards. Complete the lumber and densified firelog studies

Final analysis of all data and preparation of final report

Facilitating the disposal and utilization of Sudden Oak Death infected wood. Funding by the California Department of Forestry and Fire Protection and Region 5, USDA Forest Service.

34


Date: June 14, 2005 Report Period: May 1, 2Prepared By: Tad MasonDuring more than 2-1/2 yeSOD-diseased wood. This “To evaluate the utilization potePhytophthora ramorum infected Plans are now underway to scalaccepted at either collection yarProject Activities:

May 4 – met with material as feedstoyard at Ben LomonView’s Watsonvill May 16 + 17 – Com

insect traps and che May 17 – Conduct

at Marin and Santa

Challenges: None Opportunities: None Highlights of Projected A Monitor deliveries a Prepare to close dow

operation for both ya Conduct final vegeta Complete the lumbe Final analysis of all


University of California Cooperative Extension SODBusters Project Hotline: 1-866-SOD-7411 (1-866-763-7411)




005 through May 31, 2005 , SODBusters Project Coordinator ars of operation the collection yards received more than 1,200 tons of potentially woody biomass was used to support the project goals, which include: ntial of host tree species, identify best and most appropriate uses, and develop protocols for handling materials”.

e back operations at both collection yards. June 17, 2005 is the last day that SOD material will be d.

Summit Views LLC to review Scope of Work (attached) to conduct a test using SOD ck for a densified firelog operation. SOD material from the SODBusters collection d and the Out of the Woods sawmill has been dried and prepared for use at Summit e operation.

pleted 6 month vegetation sampling at Marin Collection Yard. Also serviced the cked the SOD firewood storage area. ed an Implementation Team meeting to coordinate the closing of the collection yards Cruz.

ctivities in the next thirty days: nd activities at both collection yards. n the collection yards as the SODBusters project comes to a close. Last day of rds in June 17. Arrange for processing of any SOD material on site at the yards. tion and insect sampling at the collection yards. r and densified firelog studies. data in preparation of final report.

35


Appendix II – Presentations and Articles Delivered in 2005 Following is the list of papers and posters presented and reference about the project in newsletters during the reporting period from January 1 to June 30, 2005.

“Evaluating the Survival of Phytophthora ramorum in Firewood” a poster presented at the SOD Science Symposium II, Monterey, CA, Jan 20, 2005.

“Understanding the Disposal and Utilization Options for Wood Infected by Sudden

Oak Death”, a paper presented at the SOD Science Symposium II, Monterey, CA, Jan 21, 2005.

“Disposing and Utilization of Wood Waste from SOD Areas”, paper presented at the

Washington Organic Recycling Council Meeting WSU Research Station, Almendinger Center, Puyallup, WA, March 31, 2005.

COMTF monthly newsletter Report June 2005 issue published abstract on our

firewood project.

COMTF monthly newsletter Report August 2005 issue published abstract on SODBusters project.

“Understanding the Disposal and Utilization Options for Sudden Oak Death-

Diseased Wood” paper submitted and accepted for publication in the proceedings of the Sudden Oak Death Science Symposium II. Published as a USDA Forest Service General Technical Report PSW-GTR….

36

“Evaluating the Survival of Phytophthora ramorum in Firewood” Poster presented at the SOD Science Symposium II, Monterey, CA, January 20, 2005

37

36

“Understanding the Disposal and Utilization Options for Wood Infected by Sudden Oak Death” Paper presented at the SOD Science Symposium II, Monterey, CA, January 21, 2005.

39

John Shelly, Ramnik Singh, Christine Langford University of California-Berkeley

Tad Mason, TSS Consultants

Utilization of Sudden Oak Death – Diseased Wood

January 21, 2005

Presented atSOD Second Science Symposium, Monterey, CA

Project funded by CA Dept. of Forestry and USDA Forest Service, Region 5

Objectives1. Develop project with client input

– Coordinating Committee• CDF, CDFA, CIWMB, USFS, COMTF, UCCE,

Santa Cruz and Marin County staff

– Private Sector input• Arborists, forest landowners, tree service

companies, biomass powerplant operators, waste management companies, firewood dealers, hardwood processors

Objectives1. Develop project with client input2. Develop protocols for transporting SOD-

diseased wood and monitoring utilization activities

– Material accepted from “trained” operators– Paper trail from source to collection yard to end use– Sampling and testing procedures– Utilization guidelines– Firewood notice for customers

Objectives1. Develop project with client input – steering and

management committees2. Develop protocols for transporting SOD-diseased wood

and monitoring utilization activities

3. Set up two collection yards– Marin County -- Marin Resource and

Recovery Center, San Rafael– Santa Cruz County – Ben Lomond Transfer

Station, Ben Lomond

Objectives1. Develop project with client input2. Develop protocols for transporting SOD-diseased wood and

monitoring utilization activities3. Set up two collection yards

4. Evaluate SOD-diseased wood for best use– Biomass Power Plant Fuel– Wood Products (lumber)– Firewood

Objectives1. Develop project with client input2. Develop protocols for transporting SOD-diseased wood and

monitoring utilization activities3. Set up two collection yards4. Evaluate SOD-diseased wood for best use

5. Operate collection yards and monitor P. ramorum levels in and around the yard

40

Monitoring SitesTransects adjacent to the

collection yardA – host vegetationB – host vegetationC – host vegetation

Control plots more than 1000 feet from the collection

yardD – host veg. and beetleE – host veg. and beetle

Plots in the collection yardF – beetle and delivered mat.G - beetle

Marin County SOD Collection Yard

Marin Resource and Recovery, San Rafael, CA

Marin County Collection Yard

Monitoring Sites

Plots adjacent to the collection yard

A – host vegetationB – host vegetationC – host vegetationD – host vegetationG – beetleH – beetle

Plots in the collection yardE – host vegetationF – delivered mat. & beetle

Santa Cruz Collection Yard

County Transfer Station, Ben Lomond, CA

Santa Cruz Sawmill Site

Davenport, Ca

Monitoring SitesPlots adjacent to the

sawmillA – host veg. and beetlesB – host veg. and beetlesC – host veg. and beetles

Plots in the collection yardD – processed material, beetles, sentinel plantsE - processed material and sentinel plants

Sawmill Site

41

Every 2

weeks Monthly Every 2

months Every 6 months

As needed

Delivered chip material M, SC

Sawlogs SC Airborne dust M SM Grinder fines M, SC Bay leaves from bins M, SC Sentinel Rhododendrons M, SC SM

Lumber SM Firewood when split M,SC,SM Stored firewood M, SM Site host plants M,SC, M Beetles M SC SM Rain water M

Sampling Schedule at the SOD Collection/Processing Sites

M = Marin County Yard SM = Sawmill SC = Santa Cruz Yard


Test Methods

• Host Vegetation– Sampling within circular plots of 20 ft radius (48 plots)

• CA bay laurel leaves collected for culture and PCR• Coast live oak and tanoak symptoms recorded

• Chips, Sawdust, Firewood, and Fines (545 samples)– Pear baiting in water, culture, microscopic ID

• Scolytidae (8 plots)– Beetle count

Tub Grinder Processing SOD Logs Chips Delivered to Santa Cruz Yard

Delivery of SOD chips to Power Plant

Fuel for Biomass Powerplants

Processing Firewood

Firewood air dried for 9 months before it is released for sale

Processing Logs into Lumber

42


Santa Cruz (12 months)

# of Trees Tons # of Trees Tons

Lithocarpus densiflorus (tanoak)

761 na na

Quercus agrifolia (coast live oak)

160 na na

Quercus kelloggi (California black oak)

5 na na

Umbellularia californica (California bay laurel)

3 na na

Total 929 trees 856 ton 636 ton

Average/active month 45 ton 46 ton

SOD-diseased Material Delivered to the Marin Yard

Disposal and Utilization of SOD-Diseased Wood

• Marin County Collection Yard– 76% to biomass power plant (650 ton)– 24% to firewood (206 ton)

• Santa Cruz Collection Yard– 94% to biomass power plant (598 ton)– 5% to lumber (32 ton)– 1% to firewood (6 ton)

Host Trees with P. ramorum or SOD symptoms at the Santa Cruz yard

0

20

40

60

A B C D E

Plot Location

Perc

enta

ge o

f Hos

t Tr

ees Fall 2003

Spring 2004Fall 2004

baseline baseline

49 of the 51 total California bay laurel trees are in Plot B and C

(in collection yard)

Host Trees with P. ramorum or SOD symptoms at the Marin yard

0102030405060708090

450

500

550

600

650

700

>100

0

Distance from Collection Yard (feet)

Perc

enta

ge o

f Hos

t Tre

es in

Pl

ot

Spring 2003Fall 2003Spring 2004

Baseline Infestation before opening of yard

0

50

100

150

200

6/28/2003 1/14/2004 8/1/2004 2/17/2005

Date

Num

ber o

f Bee

tles

Inside yardControl GControl H

Scolytidae Activity at the Santa Cruz yard

no delivery in fall 2004

Scolytidae Activity at the Marin Collection Yard

0

500

1000

1500

2000

2500

03/20/03 06/28/03 10/06/03 01/14/04 04/23/04 08/01/04 11/09/04 02/17/05Date

Num

ber o

f Bee

tles

Control DControl EInside yardAdjacent to yard

inside collection yard

43

Marin CY Santa Cruz CY Davenport SawmillSample

# Tested P. ramorum positive # Tested P. ramorum

positive # Tested P. ramorum positive

Chips 63 1 (1%) 21 1 (<1%) Grinder fines 12 0 (0%) 9 0 (0%) Fresh Split Firewood 100 8 (8%)

45 0 (0%)

Seasoned Firewood (26 week) 85 1 (1%)

Dust (Air Monitoring) 125 0 (0%)

6 0 (0%)

Grinder Dust/sawdust 41 8 (20%)

11 1 (1%) 41 0 (0%)

Sentinel Rhododendrons 14 0 (0%)

4 0 (0%) 2 0 (0%)

Bay leaves (from collection bins) 8 2 (25%)

Rainwater 3 1 (33%)

Summary of P. ramorum Monitoring at the Collection Yards/Processing Sites

Summary of Preliminary Data• Viable P. ramorum spores were collected at the collection

yards from grinder dust, delivered chips, and firewood

• No evidence has been gathered to support the hypothesis that collecting, sorting, or processing SOD diseased wood influences infestation levels in host plants at or near the site– SOD disease levels in existing host vegetation and beetle count

surrounding the collection yards has not increased above baseline levels during the past 2 years

• More data over a longer time is needed– Further analysis of P. ramorum survivability in firewood is

underway (refer to Shelly, Singh, Langford, Mason poster)

Future Project Activities• Continue operation/monitoring at the 2 collection

yards, the Soledad power plant, and the Davenport sawmill

• Continue wood property/lumber quality tests• Explore utilization potential for densified firelogs

and edible mushrooms• Funding for continued operation of collection

yards


44

“Disposing and Utilization of Wood Waste from SOD Areas” Paper presented at the Washington Organic Recycling Council Meeting WSU Research Station, Almendinger Center, Puyallup, WA, March 31, 2005.

45

John ShellyUniversity of California-Berkeley

Cooperative Extension

Disposing and Utilization of Wood Waste from SOD Areas

March 31, 2005

Project funded by CA Dept. of Forestry and USDA Forest Service, Region 5

Presented at

Washington Organic Recycling Council MeetingWSU Research Station, Almendinger Center

Puyallup, WA


Monitoring SitesTransects adjacent to the

collection yardA – host vegetationB – host vegetationC – host vegetation

Control plots more than 1000 feet from the collection

yardD – host veg. and beetleE – host veg. and beetle

Plots in the collection yardF – beetle and delivered mat.G - beetle

Marin County SOD Collection Yard

Marin Resource and Recovery, San Rafael, CA

Santa Cruz County Collection Yard

Santa Cruz County Sawmill Site

Tub Grinder Processing SOD Logs Chips Delivered to Santa Cruz Yard

Delivery of SOD chips to Power Plant

Fuel for Biomass Powerplants

46

Processing Firewood

Firewood air dried for 9 months before it is released for sale

Processing Logs into Lumber

SOD-Diseased Wood Delivered to the Collection Yards

4645Total

636856929

3CA bay laurel

5CA black oak

160Coast live oak

761Tanoak

Green Tons# treesGreen Tons# trees

Santa Cruz Cnty CYMarin County CYSpecies

Disposal and Utilization of SOD-Diseased Wood

~ 1500 green tons delivered

1250 tons (84%) to biomass power fuel210 tons (14%) to firewood

30 tons (2%) to lumber

Host Trees with P. ramorum or SOD Symptoms at the Marin County Yard

0102030405060708090

450

500

550

600

650

700

>1000


Perc

enta

ge o

f SO

D-D

isea

sed

H

ost T

rees Spring 2003

Fall 2003Spring 2004


Scolytidae Activity at the Marin Collection Yard

0

500

1000

1500

2000

2500

03/20/03 06/28/03 10/06/03 01/14/04 04/23/04 08/01/04 11/09/04 02/17/05Date

Num

ber o

f Bee

tles

Control DControl EInside yardAdjacent to yard

inside collection yard

47

1 (33%)3Rainwater

2 (25%)8Bay laurel leaves

0 (0%)0 (0%)20 (0%)40 (0%)14Sentinel rhododendrons

0 (0%)411 (9%)118 (20%)41Grinder/saw dust

0 (0%)120 (0%)60 (0%)125Air-borne dust

1 (1%)85Air-dried firewood

0 (0%)458 (8%)100Fresh firewood

0 (0%)12Grinder fines

1 (1%)211 (1%)63Chips

P. ramorumpositive

# tested

P. ramorumpositive

# tested

P. ramorumpositive

# tested

P. ramorumpositive

# tested

PowerplantSawmillSanta Cruz C. YardMarin C. YardSample

Monitoring Results from Start of Project to Present

47.899.719.30.5784.8

24Overall Average

56.598.017.90.5690.61GoodCA black oak

43.7102.820.80.7075.33GoodCoast live oak

45.2113.421.90.6076.03LowTanoak

50.587.917.70.6081.28ModerateTanoak

47.0103.119.50.5592.19GoodTanoak

Yield (%)

Green Lumber

Vol per log (bd. ft.)

Avg. Diameter (in)

Avg. SG

Avg. MC (%)

Number of logs

Log Quality

Species

Lumber Yield and Wood Quality

Summary of Preliminary Data• Viable P. ramorum spores were collected at the collection

yards from grinder dust, delivered chips, and firewood

• No evidence has been gathered to support the hypothesis that collecting, sorting, or processing SOD diseased wood influences infestation levels in host plants at or near the site– SOD disease levels in existing host vegetation and beetle count

surrounding the collection yards has not increased above baseline levels during the past 2 years

• More data over a longer time is needed– Further analysis of P. ramorum survivability in firewood is

underway (refer to Shelly, Singh, Langford, Mason poster)

http://groups.ucanr.edu/SODBusters

NOTICE: FIREWOOD AND SUDDEN OAK DEATH

DO NOT MOVE THIS FIREWOOD OUTSIDE OF THE COUNTY IN WHICH IT WAS PURCHASED WITHOUT READING THE FOLLOWING.

To limit the movement of a potentially lethal tree disease the state of California requires that firewood of certain host species obtained in a county within the regulated area NOT be transported outside of the regulated area.

The firewood you purchased was produced in a county that is within the state regulated area for Sudden Oak Death (SOD). The regulated area includes 14 coastal counties in California - from Monterey to Humboldt. This regulated area was established to restrict the potential spread of a plant pathogen known as phytophthora ramorum. This pathogen is thought to cause the SOD disease that is responsible for killing large numbers of coast live oak and tanoak trees in the coastal zone of California. The majority of firewood produced in the counties within this regulated area comes from host trees that may carry this pathogen (see reverse side for information on the host tree list). Although the risk of the pathogen surviving in thoroughly dried firewood is low, recent evidence suggests it is possible.

Details of the state regulation can be obtained from your County Agricultural Commissioner or from the California Food and Agriculture Code (section 3700) and can be accessed by searching for “Oak Mortality Disease Control” through the California Department of Food and Agriculture home page:

http://www.cdfa.ca.gov

RECOMMENDED PROCEDURES WHEN WORKING

WITH SOD-DISEASED MATERIAL

• Inform personnel that they are working in a Phytophthoraramorum

• Conduct operations during the dry season whenever possible and try to utilize paved and graveled roads.

• After working in an infested area, remove or wash-off accumulations of plant debris (especially foliage) and mud from vehicles and heavy equipment, etc. before traveling to another site.

• After cleaning debris from chipping equipment run non-diseased wood through the chipper to clear it of residual diseased material.

• A SODBusters transport certificate (TC) must accompany all loads of SOD-diseased material to be delivered to the SODBusters collection yard

48

Future Project Activities• Continue operation/monitoring at the 2 collection

yards, the Soledad power plant, and the Davenport sawmill

• Continue wood property/lumber quality tests• Explore utilization potential for densified firelogs• Final report delivered Fall 2005


49

“Evaluating the Survival of Phytophthora ramorum in Firewood” COMTF Report June 2005 (newsletter article)

50

51

52 52

“The Utilization of Sudden Oak Death-Diseased Woody Material” COMTF Report, August 2005 (newsletter article)

53

54

55

“Understanding the Disposal and Utilization Options for Sudden Oak Death-Diseased Wood” Paper submitted and accepted for publication in the proceedings of the Sudden Oak Death Science Symposium II. Published as a USDA Forest Service General Technical Report PSW-GTR….

56

Understanding the Disposal and Utilization Options for Sudden Oak Death-Diseased Wood 1

John Shelly2, Ramnik Singh2, Christine Langford,2 Tad Mason3

Abstract

Removing trees inflicted with the Sudden Oak Death (SOD) disease is often necessary because of hazard issues

or homeowner/landowner desires. An alternative to disposal of this material is to find acceptable uses for this

diseased material. A series of studies is being conducted to help understand the risk of spreading the SOD-

diseased wood through disposal and utilization activities. Two collection yards were set up in California for

wood suspected of being infected with SOD, one in Marin County and one in Santa Cruz County. More than

1,155 tons of woody, SOD host material has been processed through the collection yards since May 2003, most

from the removal of hazard trees. This material was converted into fuel for biomass power plants, firewood, and

lumber. In addition to operating the collection yards, this project included periodic monitoring for Phytophthora

ramorum (P. ramorum) spores during various stages of the processing and transportation by sampling the

delivered host material and monitoring the host vegetation growing in and around the collection yards.

The periodic sampling of woody materials transported to and processed in the collection yards yielded a small

number of positive cultures of P. ramorum isolated from a variety of the unprocessed and processed materials.

Keywords: Sudden Oak Death, wood properties, firewood, biomass, salvage lumber, disease monitoring

Of the 418 samples collected, the following tested positive: 2 of 84 chip samples, 2 of 8 bay laurel leave

samples, 8 of 145 samples of freshly split firewood, 1 of 85 samples of firewood air dried for about 6 months, 9

of 93 grinder and saw dust samples, and 1 of 3 rainwater runoff samples. Furthermore, the sampling results of

the host vegetation growing in and around the collection yards confirmed the presence of P. ramorum at each

site before operations began but continued sampling has not revealed any significant infestation increase.

1A version of this paper was presented at the Sudden Oak Death Second Science Symposium: The State of Our Knowledge, January 18-21, 2005, Monterey, California. This project is in part co-funded by the USDA Forest Service, Region 5 State and Private Forestry and the California Department of Forestry and Fire Protection (CDF), under CDF Agreement # 8-CA-01257. 2 University of California Cooperative Extension Advisor, [email protected]; Post Graduate Researcher, [email protected]; Staff Research Associate, [email protected]; University of California Richmond Field Station, Richmond, CA 94804. 3 Forester, [email protected]; TSS Consultants, Rancho Cordova, CA

57

mailto:[email protected]




This early data suggests that alternatives to disposal exist for SOD-diseased wood. Furthermore, although viable

P. ramorum spores can be isolated from various stages of processing at the collection yards, no evidence has

been gathered to support the hypothesis that the collection, sorting, and processing activities in the collection

yards increases SOD disease levels in and around the sites.

Introduction This project was initiated in response to concerns raised by the California Oak Mortality Task Force (COMTF) that disposing or using Sudden Oak Death-diseased (SOD) woody materials would spread this disease that is potentially lethal for many hardwood trees across the country. The potential to spread plant diseases by moving infected plants and plant materials from one location to another is well documented in the literature (Erwin and Ribeiro 1996; Garbelotto 2003; Davidson et al. 2002). The list of host plants for Phytophthora ramorum (P. ramorum), the primary pathogen of the disease, continues to grow with the possibility that many of the important tree species of California’s forests could become hosts (Garbelotto et al. 2003). Unlike most other Phytophthora species, P. ramorum cankers are found highly associated with the bark of host trees (Storer et al. 2001). Also, two beetles of the Scolytidae family, the western oak bark beetle (Pseudopityophthorous pubipennis) and the oak ambrosia beetle (Monarthrum sp.) are also known to be highly associated with this disease in infected trees (Storer et al. 2001). However, the role these beetles play in the spread of the disease is not well understood since the high incidence of attack appears to coincide with the latter stages of the disease (Furniss and Carolin 1977). Although it is considered unlikely that the beetles play a significant role in disease spread they could be a valuable tool for measuring SOD activity in a region. Based on an initial list of host plants and the realization that suitable hosts could be found throughout the country, public agencies were quick to regulate the transport of diseased material and implement quarantine zones. The California Department of Food and Agriculture established intrastate regulations in 2001 (Anon. 2005) followed by the enactment of federal interstate regulations by the US Animal and Plant Health Inspection Service (Anon. 2002). Both sets of regulations were enacted before studies of SOD-diseased wood could be completed. Recognizing that the likely pathways for the spread of P. ramorum are by water, soil, infected plant materials, and perhaps by air, the regulations encourage that infected material be quarantined and left in place if possible. However, it is not always possible to leave infected material at the site of the infestation. Many SOD-diseased trees are in urban areas, public areas, or adjacent to roads or utility lines. Such trees are often considered hazard trees and they must be removed. The removal of large numbers of these trees results in high, unbudgeted expenditures and often a disposal problem. As a woody material, this biomass could generate some value as consumer products but it was unclear if utilization activities can contribute to the spread of the disease. Under current regulations, if host plants and plant materials including wood and unprocessed wood products are transported outside of a regulated county they become subject to intensive inspection and permitting. Based on the premise that P. ramorum in trees thrives only on leaves or directly beneath the bark, wood and wood products can be exempt from the regulations as long as they are free of bark. However, the actual risk of spreading the disease by moving wood and wood products, with or without bark, was not well understood. The goals of the project reported in this paper were to study the risks of moving material infected with P. ramorum from the site of its initial infection to a central location or processing facility and to identify potential uses for the diseased material. The approach used to gauge the risk was to track the infestation levels of P. ramorum and bark beetles in and around collection yards during the life of this project. Two collection yards for SOD-diseased wood were set up and actively managed under this project. The Marin County collection yard, located at Marin Resource and Recovery in San Rafael, California, opened in May 2003 and operated for 20 months at the time this paper was written. The Santa Cruz County yard, located at the Santa Cruz County transfer station in Ben Lomond, California, was opened in December 2003 and operated for 13 months. Both yards are scheduled to close by July 2005.

Objectives The overall objectives of the project included:

• Design a comprehensive disposal and utilization plan for Marin and Santa Cruz Counties

that incorporates the views of public agencies and private enterprise.

• Develop protocols for the removal and transportation of SOD-diseased woody material

and for monitoring the potential spread of disease

• Evaluate the relationship between transporting and processing SOD-diseased wood and

the risk of spreading SOD disease

58

• Evaluate the basic wood properties of SOD-diseased wood and the value-added

utilization potential and implement the distribution of SOD-diseased wood to appropriate

markets.

Methods To create a disposal and utilization plan that addressed the objectives of the project, a series of meetings was conducted with representatives of interested organizations and stakeholders. These included state and county agencies responsible for the removal and disposal of woody biomass as well as tree service companies, arborists, land managers, and commercial users of woody biomass. An outcome of these meetings was the establishment of two collection yards to serve as a central location for the drop-off of host trees suspected of having SOD. Consultations with state regulators and other researchers studying SOD led to a set of protocols used in this project to define the rules of participation in the project and the methods used to monitor the activities. Only host material suspected of being infected with P. ramorum and identified by a person having received training in SOD symptoms was accepted at the collection yards. This material had to be removed and transported to the collection yard by a tree service company or other qualified expert following the transportation guidelines distributed to all potential participants and also posted on the project internet web site (http://groups.ucanr.org/sodbusters). Once at the yard, the SOD-diseased material temporarily stored at the site was physically separated from other woody biomass operations. This material was stored until enough volume was collected to justify moving it to a utilization market. During this sequence of events the material, the site, surrounding environment, and processing activities were monitored for the presence of P. ramorum and bark beetle activity according to the protocols described in an earlier progress report (Shelly et al. 2004). In summary, the following monitoring was conducted according to the schedule outlined in Table 1.

• Determined base line levels of infestation in the area surrounding the collection yard by

inspecting all of the following host plants found in circular plots (6 m radius) spaced 20

meters apart along transects emanating from the collection yard.

o Coast live oak (Quercus agrifolia) – inspected for SOD symptoms

o California bay laurel (Umbellularia californica) – collected symptomatic leaves from

trees taller than 2 meters that were used for laboratory examination (see culture

techniques below)

• Monitored beetle levels by capturing insects in ethanol-baited, “Lindgren” beetle traps and

periodically counting the catch of scolytids.

• Periodically sampled collection yard materials

o Delivered SOD-diseased woody biomass (chips, branches, leaves, and logs)

o P. ramorum susceptible rhododendron plants (Rhododendron var. Colonel Coen),

potted and placed in the collection yard (sentinel rhododendrons)

o Airborne dust generated during unloading of SOD-diseased material from trucks

(only at the Marin County yard and the Soledad biomass power plant)

o Rain water runoff from chip piles (only at the Marin County yard)

• Periodically sampled materials during processing activities

o Airborne dust generated during wood grinding operations

o Small wood particles that fall from the grinders (grinder fines)

o Firewood with bark as it was processed

59

o Sawdust from sawmill as logs were processed into lumber

• Periodically sampled processed firewood as it dried

Table 11 – Schedule of sampling at each collection yard (M = Marin county collection yard, SC = Santa Cruz County collection yard, SM = sawmill site in Davenport, S = Soledad biomass power plant) Item Sampled Every 2

weeks Every Month

Every 2 months

Every 6 months

As needed

Host plants in sample plots

M,SC, SM

Sentinel rhododendrons M, SC SM, S Beetles M, SC SM Rain water runoff from collection yard

M

Delivered chip material and CA bay laurel leaves

M, SC

Delivered sawlogs SC Airborne dust generated during delivery

M S

Grinder fines and sawdust

M, SC, SM

Lumber SM Freshly split Firewood M, SC,

SM Stored firewood M, SM

Culture techniques All chip, wood particle, dust, water and solid wood samples were subjected to the pear baiting technique to determine the presence of P. ramorum. Hard, green d'Anjou pears without wounds or bruises were partially submerged for 3 days at 20° C in deionized water containing the material being tested. The pears were then removed from the water and air dried at 20° C for 2-5 days. Any characteristic Phytophthora lesions that appear on the pears were isolated and placed on an agar growth medium prepared with ampicillin, rifampicin, and pimaricin (PARP) using sterile techniques. Organism that grew on the PARP plate were examined for P. ramorum characteristics to determine the presence of the pathogen (Blomquist and Kubisiak 2003). Leaves collected from host plants were not pear baited, the Phytophthora lesions on the leaves were directly plated on the PARP. The Plant Pest Diagnostics Center, California Department of Food and Agriculture (CDFA) in Sacramento performed DNA analysis using polymerase chain reaction (PCR) techniques to confirm the presence of P. ramorum on all plates that grew organisms with P. ramorum characteristics.

Utilization analysis Data gathered on the properties of the diseased wood collected in the study area included tree size and form, gross wood characteristics, wood moisture content at the time of the diseased wood delivery, and wood density. Moisture content was measured on solid wood specimens taken from the processed firewood and logs selected for lumber processing. The same specimens were also used to measure the density. These properties were used to determine the level of degradation in the wood and to identify the best use for the material. Products considered included biomass powerplant fuel, firewood, and lumber.

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Results A total of 1,155 tons of potentially SOD-diseased wood was delivered and processed at the two collection yards (Table 2). In the 20-month period from May 2003 to December 2004, the Marin County collection yard received 856 tons from 14 private tree service companies and 3 public works departments. The Santa Cruz County collection yard received 299 tons in the 12-month period from December 2003 to December 2004, all as hazard tree removals under contact of the County of Santa Cruz during the 6-month period from December 2003 to June 2004. At the Marin County yard the deliveries were tracked by species. Of the 929 trees removed and delivered to the yard, 761 (82 percent) were tanoak (Lithocarpus densiflorus), 160 (17 percent) were coast live oak (Quercus agrifolia), 5 (0.5 percent) were California black oak (Quercus kelloggi), and 3 (0.3 percent) were California bay laurel (Umbellularia californica). Although the deliveries could not be tracked by species at the Santa Cruz County yard, the species breakdown is assumed to be similar based on the inventory of hazard trees by the county in which tanoak made up about 75 percent of the material and coast live oak 21 percent.

Table 12 – Breakdown of the SOD-diseased material delivered to the Marin County collection yard and the Santa Cruz County collection yard


Santa Cruz (12 months)

# of Trees

Tons # of Trees

Tons

Lithocarpus densiflorus (tanoak) 761 na na na

na na

Quercus agrifolia (coast live oak) 160 na na na Quercus kelloggi (California black oak) 5 na na na Umbellularia californica (California bay laurel) 3 na na na

Total 929 856 299 Average deliveries/active month 45 46

Of the total 1,155 green tons of material collected, about 84 percent were processed into biomass powerplant fuel, 14 percent converted into firewood, and 2 percent processed into lumber. The commercial biomass power plants that received the biomass fuel from this project were in Rocklin, Woodland, and Soledad, California. All of the biomass fuel chips processed at the Santa Cruz County yard were sent to the Soledad facility, a total of 283.4 green tons. The Marin County yard processed 649.5 tons of biomass fuel chips that were distributed to all three of the powerplants listed above.

Monitoring for changes in SOD infestation

Host vegetation A baseline of SOD infestation was established before each collection yard began operations by sampling the host vegetation in and around each collection yard. The same trees were reexamined every 6 months throughout the duration of the project to determine changes in the level of the disease. The baseline survey of P. ramorum infestation at the Marin County site in the spring of 2003 showed that 69 percent of the bay laurel trees in all plots were infected with P. ramorum. This overall infestation level decreased to 61 percent in the spring of 2004 after 1 year of SOD-diseased wood collection activities. This was due to a few trees that exhibited SOD symptoms initially but were no longer symptomatic in subsequent sampling. This may not actually indicate a real drop in infestation but it could be a reflection of the natural variation of the symptoms. Although the rate of infestation appeared to be greater closest to the collection yard (Figure 1), this is believed to not be influenced by the collection yard activities. The collection yard is located at the base of a steep slope and all of the plots closest to the collection yard are at the base of the slope. The higher percentages of infected trees at 450 feet from the collection yard were likely a reflection of higher natural P. ramorum infestations expected at the bottom of a steep slope. The observed lower infestation rates in the fall were a reflection of the difficulty in sampling infected bay laurel leaves in the fall when most of the infected leaves have fallen from the tree.

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0102030405060708090

400 450 500 550 600 650 700 750 800 850 900 950 1000


Per

cent

age

of H

ost T

rees

Spring 2003Fall 2003Spring 2004


Figure 7 – Percentage of host trees in each sample plot at the Marin County Collection yard that are infected with P. ramorum. Similarly, no changes were observed with the coast live oak trees in the sample plots that could be explained by the collection yard activities. The overall level of symptomatic coast live oak trees in all transects remained constant, but one additional coast live oak developed symptoms in a control plot far from the collection yard activities and one of the symptomatic trees in a plot close to the collection yard became symptom free. None of the sentinel rhododendron plants placed in the collection yard developed positive P. ramorum cultures. Similar results were found at the Santa Cruz County collection yard where the slight changes observed in the infestation were seasonal and also located in plots far from the collection yard activities.

Beetle activity Bark beetle activity in and around the two collection yards is summarized in Figure 2. The beetles were most active in both yards in the spring/early summer months with a secondary period of activity in the fall. This is consistent with the expected life cycle of bark beetles. During late May to early June 2004 the beetle count in the trap inside the Marin County yard reached a peak of 2,352 beetles. This dramatic increase in bark beetle activity coincided with numerous deliveries of SOD-diseased hazard trees. A similar peak also occurred at the same time in the Santa Cruz County yard; this peak was also associated with numerous deliveries of SOD-diseased hazard trees. The beetle counts in the control D and E baited traps, which were located the furthest from the collection yard, were generally quite a bit less than the counts inside the collection yards with the exception of the August 2003 peak for control 2 at the Marin County site. This control 2 count was in the plot farthest from the collection yard in an area with many dead and dying coast live oak trees and is believed to be a reflection of normal beetle activity and not related to the collection yard activities. With the exception of the traps adjacent to the collection yards that may be influenced by the collection yard activities, the other traps showed a good record of the background beetle activity in the area.

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0

50100

150

200

250300

350

3/20/03 6/28/03 10/6/03 1/14/04 4/23/04 8/1/04 11/9/04 2/17/05

Num

ber o

f Bee

tles

at A

Control 1 Control 2 Inside yard Adjacent to yard

0

50

100

150

200

250

300

350

3/20/2003 6/28/2003 10/6/2003 1/14/2004 4/23/2004 8/1/2004 11/9/2004 2/17/2005

Date

Num

ber o

f Bee

tles

at B

Figure 8 – Scolytid activity at the collection yards (A is Marin County, B is Santa Cruz County)

Monitoring of delivered materials The results of the monitoring activities for P. ramorum in the host material delivered to and processed at both collection yards are presented in Table 3. To date, P. ramorum has been cultured from the following specimens:

• two of 8 bay leaf samples recovered from the chips bin in the collection yard

• two of 84 samples of chips from the collection bins

• eight of 145 pieces of freshly split firewood

• one of 85 pieces of firewood dried for about 6 months

• nine of 93 specimens of grinder and saw dust collected next to the wood grinders and sawmill

• one of 3 samples of rainwater runoff from chip piles None of the samples from air-borne dust in the collection yards, near the processing equipment, or the sentinel rhododendron plants have tested positive for P. ramorum.

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Table 13 – P. ramorum monitoring of SOD-diseased material delivered or processed at both collection yards Marin C. Yard Santa Cruz C. Yard Sawmill Powerplant Sample

#

tested

P. ramorum

positive

#

tested

P. ramorum

positive

#

tested

P. ramorum

positive

#

tested

P. ramorum

positive

Chips 63 1 (1%) 21 1 (1%)

Grinder fines 12 0 (0%)

Fresh firewood 100 8 (8%) 45 0 (0%)

Air-dried

firewood

85 1 (1%)

Air-borne dust 125 0 (0%) 6 0 (0%) 12 0 (0%)

Grinder/saw

dust

41 8 (20%) 11 1 (9%) 41 0 (0%)

Sentinel

rhododendrons

14 0 (0%) 4 0 (0%) 2 0 (0%) 0 (0%)

Bay laurel

leaves

8 2 (25%)

Rainwater 3 1 (33%)

Wood properties and lumber quality Twenty-four logs (15.5 tons total weight) of SOD-diseased logs were selected for sawlog potential at the collection yard and delivered to the sawmill in Davenport, CA. The species mix of the sawlog test was 21 tanoak, 2 coast live oak, and 1 California black oak. The yield and physical properties of the logs and lumber produced is summarized below in Table 4. The average moisture content of the heartwood and softwood lumber was 84 percent and 74 percent respectively. The specific gravity (oven dry mass/green volume) of the tanoak processed was 0.57. The logs were processed into 8-foot long lumber measuring 5/4-inch thick and various widths of 3-inch, 4-inch, and 6-1/4”. All of the solid wood residue from the sawmilling operation was processed into firewood and the sawdust was collected and stored on site for future analysis and potential utilization. The total log volume of 412.84 ft3 (4,954 board feet (bf)) produced 188.89 ft3 (2393 bf) of green, 5/4-inch thick lumber or a lumber yield of 47.8 percent. The remaining 52.2 percent of the log volume not converted into lumber was either sawdust or a solid wood residue that was converted to firewood.

Table 14 – Green lumber yield and wood properties of test sawlogs by species and log quality Species Log

Quality Number of logs

Avg. MC (%)

Avg. SG

Avg. Diameter

(in)

Green Lumber

Vol. per log (bf)

Yield (%)

Tanoak Good 9 92.1 0.55 19.5 103.1 47.0 Tanoak Moderate 8 81.2 0.60 17.7 87.9 50.5 Tanoak Low 3 76.0 0.60 21.9 113.4 45.2 Coast live oak Good 3 75.3 0.70 20.8 102.8 43.7 CA black oak Good 1 90.6 0.56 17.9 98.0 56.5

Overall 84.8 0.57 19.3 99.7 47.8

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Average 24 The logs were evaluated for quality on the basis of log form (straightness and taper), presence and level of decay, level of beetle infestation, and the presence of heart stain (known to be highly correlated with drying defects). The lumber yield varied from 45.2 percent to 50.5 percent but this variation was not correlated with log quality, the moderate category resulted in the highest yield. Similarly, no trend was identified between lumber yield and log diameter (Figure 3), moisture content, or specific gravity. Plots of yield with these factors resulted in plots similar to Figure 3.

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

0.0 5.0 10.0 15.0 20.0 25.0 30.0

log diameter (inch)

Yiel

d (%

)

Figure 9 – Green Lumber yield by log diameter

Discussion The collection yards have been successful in collecting SOD-diseased wood. The Marin County collection yard was the most active, with the support of at least a dozen tree service companies and the county of Marin. The Santa Cruz collection yard was very active during the Santa Cruz County hazard tree removal project but it proved to be a challenge to encourage the local tree service companies to participate in the collection program. These yards have collected about 1200 green tons of woody biomass from Sudden Oak Death Disease host trees, mostly tanoak (~ 80 percent) and coast live oak (~ 15 percent). The potential for this material having viable P. ramorum spores is higher than in the general population of host material because the yards only accepted material that exhibited the combination of symptoms associated with the disease. However, since the presence of P. ramorum was not positively identified in each tree the yards undoubtedly accepted some dead and dying trees that were SOD-disease free. The high correlation between the deliveries of host woody biomass to the yards and the bark beetle count inside the collection yard suggests that even though the beetles may not be a vector for P. ramorum, they are highly associated with the SOD-diseased wood. Because most of the wood delivered was from hazard trees that were dead for more than 4 months, it is suggested that the beetles were not attracted to the wood once in was in the yard but rather they came into the yard in the dead wood. Also, since the beetle counts in the traps away from the yard did not show a corresponding rise, the beetles did not appear to spread far from the collection yard. Although the relationship between massive beetle attack and tree death is not fully understood, this evidence of large numbers of beetles associated with the wood collected suggests that the beetles play an important role in the disease and further study is needed. The data gathered from the collection yard activities and the periodic sampling for P. ramorum in and around the collection yard will be used in future studies to analyze the risk of spreading SOD disease by transporting and processing biomass and wood products. Although P. ramorum was found in 23 of the 418 specimens collected (~ 5 percent), all of the positive cultures, except for firewood, were collected in unprocessed material at the collection yard or at the primary processing equipment (grinders and saws). Although no positive cultures have been obtained at the end uses of biomass power plant fuel, firewood air-dried longer than 6 months, or in processed lumber, the 8 positive cultures collected from the fresh split firewood and the 1 positive from the partially dried firewood emphasize the need to further study the survivability of P. ramorum in processed firewood. It is encouraging that none of the firewood specimens dried longer than 6 months have tested positive. Also of interest is the observation that about 2/3rds of the positive P. ramorum cultures were collected during the winter and early spring months, the rainy months. This data suggests that P. ramorum sporulation is most active during the wet weather season of the year and that the risk of spreading P. ramorum is higher during these months.

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The final evaluation of the potential lumber quality of SOD-diseased logs cannot be reported until the analysis of the kiln-dried lumber is complete. However some preliminary observations are possible. The average specific gravity of 0.57 and the average green moisture content (MC) of 85 percent are slightly lower than the previously reported values of 0.60 specific gravity and 90 percent MC, but is certainly within the range of expected normal variation (Shelly and Jackovics 2001). The 48% yield of green lumber reported in this study is markedly lower than the 60 percent green lumber conversion previously reported by Shelly and Jackovics (2001). The extra deterioration of wood quality from the decay and insect infestations in the logs surely accounts for this lower yield. The final conclusions cannot be made until the kiln dried lumber is evaluated for quality but the yield is expected to decrease another 5 to 10 percent as a result of drying defects created during kiln drying. This suggests that although lumber can be produced from SOD-diseased trees, the expected low yield of high quality lumber may limit the economic potential.

Summary The data reported on in this study indicate that viable P. ramorum spores can be collected from dead and dying Sudden Oak Death Disease host trees that are delivered to collection yards. However, no evidence has been gathered to support the hypothesis that the collection, sorting, and processing activities in the collection yards influences SOD disease infestation levels at the site. Biomass powerplant fuel and lumber are considered good uses for SOD-diseased wood if care is taken in isolating the grinder dust and sawdust generated during processing. Firewood may be a good use but more information is needed to understand the survivability of P. ramorum in firewood. The relative ranking of these options as a best use is dependent on the expected value of the product and any extra costs associated with handling the material to limit the risk of spreading SOD. This economic potential will be evaluated in future work.

Acknowledgments This project could not have been successfully implemented and managed without the assistance cooperation of the many individuals on the project Coordinating Committee (complete list posted at http://groups.ucanr.org/SODBusters) representing the California Department of Forestry, California Waste Management Board, California Department of Food and Agriculture, and the Marin County and Santa Cruz County Agricultural Commissioners Offices. A special thanks to Don Gasser, Pacific Gas and Electric Company for spearheading the early discussions of the disposal and utilization of SOD-diseased wood; Cynthia Murray, Marin County Supervisor for her early support of the project; Joe Garbarino and John Oranje, CEO and Vice President of the Marin Resource and Recovery Center; Patrick Mathews, Santa Cruz Department of Public Works and Mitch Matsumoto of Vision Recycling, Inc. for there help in operating the collection yards; Cheryl Blomquist, California Department of Food and Agriculture for her assistance in the DNA identification of P. ramorum cultures; Don Owen, California Department of Forestry for his assistance with the interpretation of bark beetle activity; and last but certainly not least, the California Oak Mortality Task Force staff members Janice Alexander, Karl Buermeyer, and Kati Facino for their assistance in public outreach, training, and information dissemination. This project was funded by the California Department of Forestry Agreement No. 8CA01257 with assistance from the USDA Forest Service, State and Private Forestry.

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no. 01-054-1). US Government Printing Office; 6827-6837.

Anon. 2005. Oak Mortality Disease Control. California Code of Regulations. Register 2005, No. 3. Section 3700. January 21, 2005. State of California.

Blomquist, C.; Kubisiak, T. 2003. Laboratory diagnosis of Phytophthora ramorum from field samples. Sudden Oak Death Online Symposium. www.apsnet.org/online/sod. American Phytopathological Society. doi:10.1094/SOD-2003-TK.

Davidson, J. M.; Rizzo D. M.; Garbelotto M. 2002. Phytophthora ramorum and sudden oak death in California: II. Pathogen transmission and survival. In: Standiford R, McCreary D, Purcell K.B. (eds). Proc. 5th Oak Symposium: Oaks in California’s Changing Landscape. Oct. 22-25, 2001. San Diego, CA. Gen. Tech. Rpt. PSW-GTR-184. USDA Forest Service, Pacific Southwest Research Station, Albany, CA.; 741-749

Erwin, D. C.; Ribeiro, O.K. 1996. Phytophthora Diseases Worldwide. St. Paul, MN: APS Press. 562 p.

Furniss, R. L.; Carolin, V. M. 1977. Western Forest Insects. Miscellaneous Publication No. 1339. Washington, DC: US Forest Service, Department of Agriculture; 654 p.

Garbelotto M. 2003. Composting as a control for sudden oak death disease. BioCycle: February 2003; 53 - 56.

Garbelotto, M., J. M. Davidson, K. Invors, P.E. Maloney, D. Huberli, S.T. Koike, and D.M. Rizzo. 2003. Non-oak native plants are main hosts for the sudden oak death pathogen in California. California Agriculture (57):1; 18 – 23.

Shelly, J. R.; Jackovics, K. 2001. Tanoak Utilization: Coordination of Tanoak Recovery and Yield Studies and Knowledge Transfer. University of California Forest Products Laboratory. Berkeley, CA. Technical Report Number 35.01.4xx. September 2001. 29 p.

Shelly, J. R.; Singh, R.; Langford, C.; Mason, T. 2004. Removal and utilization of high risk sudden oak death host material. Progress Report 3. Internal Report, January 29, 2004. University of California Wood Resources Group, Richmond Field Station, Richmond, CA. 64 p.

Storer, A. J.; Keirnan K. E.; Palkovsky, N. K.; Hagen, B. W.; Slaughter, G. W.; Kelly, N. M.; Svihra P. 2001. Sudden Oak Death: Diagnosis and management. Pest Alert #5. March 2001. University of California Cooperative Extension, Marin County, Novato, CA. 12 p.

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