Wakulla County Wildflower Management Areas 2013-14 Final Report to the Florida Wildflower Foundation October 2014 Jeffrey G. Norcini OecoHort, LLC 726 Riggins Road, Tallahassee, FL 32308 PH: (850) 491-0910, FAX: (888) 813-0090 [email protected]Cooperators Wakulla County Public Works Cleve Fleming, Project Manager; Brent Pell, Project Engineer Florida Native Plant Society, Sarracenia Chapter David Roddenberry, Kitty Lofton, Jeannie Brodhead St. Marks National Wildlife Refuge Scott Davis, Gail Fishman
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Wakulla County Wildflower Management Areas 2013-14
David Roddenberry, Kitty Lofton, Jeannie Brodhead St. Marks National Wildlife Refuge
Scott Davis, Gail Fishman
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PREFACE
Funds for this project were provided through sales of Florida’s State Wildflower license plate. The Wildflower license plate supports native wildflower planting, education and research projects statewide.
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EXECUTIVE SUMMARY
Wakulla County has been and continues to be one of the leaders in promoting and developing roadside wildflowers. In recognition of their ongoing leadership, the Foundation contracted with OecoHort, LLC to collaborate with Wakulla County Public Works, and in cooperation with the Sarracenia Chapter of the Florida Native Plant Society and St. Marks National Wildlife Refuge, to develop and implement site specific management plans that will facilitate the sustainability and spread of the best showy, naturally occurring stands of native wildflowers and grasses on county roads
Spring, summer, and fall surveys were conducted by car on April 19, July 17, and October 9, 2013, respectively, accompanied by walking forays into the sites. Of the 10 potential sites, four were selected based on showiness from spring to fall observed in 2013 as well as their potential to be sustainable and spread: one site each on Lighthouse Road (CR 30) and Spring Creek Highway (CR 365), and two on Smith Creek Road (CR 375).
Management plans were developed and included specifications for buffer areas flanking the ends of the wildflower sites. The rational for including these flanking areas was twofold – to account for species that could move into a wildflower site and detract from the site’s showiness and/or interfere with its sustainability, and second, to facilitate the gradual spread of native wildflowers/grasses into the buffers thereby increasing the size of the wildflower sites.
The management plans were provided to Wakulla County Public Works in November 2013 and implemented in 2014 within the constraints of their budget. Moreover, Wakulla County reduced mowing to ~8-ft wide strips adjacent to the edge of pavement throughout the county, except on Lighthouse Road, which was not mowed due to the high percentage of herbaceous native species in the entire right-of-way (ROW); however, the entire Lighthouse Road ROW was mowed in late July 2014 by St. Marks National Wildlife Refuge, a situation that was resolved later that summer.
Displays of native wildflowers and grasses are expected to improve at each of these sites over the next few years. Moreover, the county-wide reduced mowing width has resulted in some showy displays of wildflowers in areas other than the four designated wildflower sites. Of equal importance are the cost savings because it takes less time to mow ROWs, and the public’s apparent acceptance of the reduced mowing width.
This project should help to facilitate ecotourism in Wakulla County, serve as a model for other counties as a process to promote wildflower ecotourism and reduce mowing , and strengthen the Foundation’s panhandle wildflower initiatives.
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INTRODUCTION Wakulla County has been and continues to be one of the leaders in promoting and developing roadside wildflowers as evidenced below:
• First county to adopt a Wildflower Resolution • Well represented on Florida Panhandle Wildflower Alliance • La Florida, Land of Flowers, Community Grant – 2011, 2014 • Worked with FDOT District 3 to reduce mowing on US 98 • Sarracenia Chapter of FNPS is working on a native-plant guide for a 4.8-mile
stretch of the new bike path along Surf Rd through St. Marks National Wildlife Refuge (NWR)
Based on preliminary work conducted to identify county roads with showy stands of native wildflowers and grasses, the four roads with the best potentials sites were:
• Lighthouse Road (CR 30; the entrance road to St. Marks National Wildlife Refuge) • Surf Road (CR 372; between US 319 and US 98) • Spring Creek Highway (CR 365) • Smith Creek Road (CR 375)
Objective
Develop and implement site specific management plans that will facilitate the sustainability and spread of the best showy, naturally occurring stands of native wildflowers and grasses on the county roads mentioned previously. Management plans included specifications for buffer areas flanking the ends of the wildflower sites. Including the buffer areas accounts for species that could move into a wildflower site and detract from the site’s showiness and/or interfere with its sustainability as a showy wildflower site. Moreover, including management specifications for the buffers should facilitate the gradual spread of native wildflowers/grasses into those areas thereby increasing the size of the site.
Impact
• Strengthens Foundation’s panhandle wildflower initiatives • Promotes ecotourism in Wakulla County(including increased visitors to St. Marks
NWR) • Serves as a model for other counties as a process to promote wildflower
ecotourism.
METHODS
Spring, summer, and fall surveys were conducted by car on April 19, July 17, and October 9, 2013, respectively, accompanied by walking forays into the sites. All species observed on these dates are listed in Table 1 (page 13). In addition, the Sarracenia
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Chapter recorded images of wildflower sites along these roads on other dates from spring to fall to more accurately assess the showiness of each site throughout the year.
Specific activities for this project: • Determined wildflower sites for which to develop management plans based on
visits in spring, summer, and fall of 2013 for each of the four roads; in collaboration with Public Works
• Developed management plans for four sites • Brent Pell, Wakulla County Public Works, implemented management plans in
2014 within the constraints of the Public Works Budget • Checked sites in May 2014 • Created Flickr folder (Wakulla Wildflowers) • Will publicize project and Flickr page via Facebook after Final Report accepted
and posted to the Foundation web site
RESULTS
Of the 10 potential sites, four were selected based on showiness from spring to fall observed in 2013 as well as their potential to be sustainable and spread: one each on Lighthouse Road and Spring Creek Highway, and two on Smith Creek Road.
For each of the four sites, including the 100-ft buffers immediately adjacent to each end of the site, specifications were provided in November 2013 to Brent Pell of Wakulla County Public Works. To download a copy of the report, please click here (to open this PDF documents requires Adobe Acrobat 7.0 or later). Showy native species were classified by season in which they were flowering to inform the County about what to look for, and as an aid for developing promotional materials. Additionally, the County was informed of the following:
• The relative abundance of any species can vary substantially from year to year due to a number of factors beyond the County’s control.
• The list of observed species (Table 1, page 13), should not be considered an exhaustive list of all species that occur at a particular site.
• The species observed at each site were “snapshots” of species that were most abundant and/or identifiable (based on vegetative parts and/or flowers) on the dates of the surveys.
• Weeds that commonly occur in the area that were most likely to negatively impact aesthetics or sustainability of the wildflower sites. Moreover it was noted that while these weeds may not have been observed in a particular site, they could easily be introduced into a site by maintenance/construction equipment or vehicles, or emerge from the soil seed bank when the soil is disturbed, such as when mowers scalp the soil or a vehicle leaves the road and creates a wheel rut.
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NOTE: No action was taken to control any specific weed issue as Wakulla County did not have the budget to implement any manual or chemical weed management practices.
In 2014, Wakulla County reduced mowing to ~8-ft wide strips adjacent to the edge of pavement throughout the county, except on Lighthouse Road, which was not mowed due to the high percentage of herbaceous native species in the entire ROW; however, the entire Lighthouse Road. ROW was mowed in late July 2014 by St. Marks NWR. See page 4 and the Appendix for more details.
Brent Pell noted that the reduced mowing width has saved Wakulla County money (no cost savings figures were available) because it takes less time to mow ROWs. Mowing frequency, which can be as often as once per month from March to November, was not reduced. However, Brent pointed out that the reduced mowing width has resulted in some showy displays of wildflowers in areas other than the four designated wildflower sites. He was not aware of any negative comments about the county-wide reduced mowing width, which as he noted and I concurred, could be viewed as a positive since it indicated that the public in general accepted the reduced mowing width.
NOTE: All species mentioned in this report or the Management Specifications are listed in Table 1, page 13.
Sites
Lighthouse Road (CR 30). Lighthouse Road runs from US 98 south to the entrance booth of St. Marks NWR. Starting at the St. Marks NWR booth and proceeding about 3 miles north until the wooded canopy covers the road (just south of US 98), the mowed zone is occupied by a high proportion of native wildflowers and grasses. The best displays are on the west side of the road where the wooded area is further from the road. Of the four potential wildflower sites on Lighthouse Road, the site with the best potential site for showiness /sustainability is located at:
North end: 30.193022, -84.171655; south end: 30.192692, -84.171483 Length: about 130 ft Habitat: ruderal; moist
This site should be showy from April to October based on the diversity of showy wildflowers and grasses observed in spring, summer, and fall 2013, and if the site is not mowed except for the fall cleanup mowing.
Of particular note at this site is the occurrence of a rare, large population of Asclepias lanceolata (Fewflower Milkweed) and the state-listed endangered species, Ruellia noctiflora1 (Nightflowering Wild Petunia) (page 4).
1 Special thanks to Scott Davis, who was the first to report the occurrence of this species on Lighthouse Road.
Asclepias lanceolata
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In July 2013 and 2014, the entire ROW was mowed by St. Marks NWR personnel, despite Lighthouse Road being a county-maintained road, an effort to halt the July 2014 mowing, and the Refuge lacking an MOU with the county to mow the ROW. Wakulla County did not intend to mow the entire ROW until the late fall cleanup mowing. No part of the ROW was mowed prior to July 2014 mowing; the image of Asclepias lanceolata on page 3 shows a portion of the site as it appeared on May 28, 2014. At most, Wakulla County would have only mowed a 6-ft wide strip adjacent to the edge of pavement. Lisa Roberts wrote a letter of complaint to the Refuge for hampering the efforts of Wakulla County and the Foundation (see Appendix, page 17). St. Marks NWR responded and provided assurances that the west side of Lighthouse Road will not be mowed by the Refuge.
A weed species of concern is Cyperus esculentus (Yellow Nutsedge). If the soil were to be disturbed it could spread quickly. In addition, Cyperus esculentus roots exude allelopathic substances that can inhibit germination and growth of other species.
Spring Creek Highway (CR 365). Only one site on this road met the criteria for this project; it is on the east side about 3.8 miles south of US 98 (aka Coastal Highway).
North end: 30.090137, -84.327010; south end: 30.088683, -84.326953 Length: about 530 ft Habitat: ruderal; moist
Mowing from March to November should have been limited to about an 8-ft strip adjacent to the edge of pavement. However, in 2014, the fall cleanup mowing (25-30 ft) occurred in late September, which will substantially reduce the showy displays of fall wildflowers. It is hoped that in the future the fall cleanup mowing will not occur before mid-November.
This site should be showy in April and September/October based on the diversity of showy wildflowers and grasses observed in spring and fall 2013, and if the mowing of the roadside continues as suggested.
Of particular note are the stands of Rosa palustris (Swamp Rose) and Hibiscus aculeatus (Pineland Hibiscus) about 500 ft to the north of the wildflower site and on the west side of the road. Both of these showy native shrubs occur along the woodland edge and beyond the mow zone.
Rosa palustris Hibiscus aculeatus
April 19, 2013 October 9, 2013
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Note: While this section of Spring Creek Highway was widened by about 2 ft in 2014, overall aesthetics should not be affected as the showy wildflowers are still beyond the 8-ft mowed strip.
Two weed species of concern are Ambrosia artemisiifolia (Ragweed) and Eupatorium capillifolium (Dogfennel). While both species occur sporadically, both can easily spread and more than a few will significantly detract from the aesthetics of this site.
Showy Native Species
Spring: Cirsium horridulum, Erigeron quercifolius, Helenium pinnatifidum, Salvia lyrata, Scutellaria integrifolia, Spiranthes sp. Summer: Chamaecrista fasciculata, Centrosema virginianum, Erigeron quercifolius, Lachnanthes caroliana, Ludwigia maritima, Pluchea rosea, Rhexia mariana (occurrence of all was too limited to have a substantial aesthetic impact) Fall: Andropogon virginicus, Agalinis sp., Bidens alba, Bidens mitis, Chamaecrista fasciculata, Helianthus angustifolius, Lobelia glandulosa, Saccharum giganteum, Solidago fistulosa, Solidago sempervirens, Symphyotrichum dumosum Andropogon glomeratus – north buffer only; Carphephorus odoratissimus, Eupatorium mohrii – south buffer only Other Native Species
Species that could Negatively Impact Aesthetics or Sustainability
Site Turfgrasses: Eremochloa ophiuroides (centipedegrass), Paspalum notatum (bahiagrass) Other: Ambrosia artemisiifolia, Desmodium incanum (A potential concern if an herbicide containing imazapic is used as imazapic could increase the spread of this mat forming species), Eupatorium capillifolium, Rubus cuneifolius
North Buffer
Turfgrasses: Eremochloa ophiuroides, Paspalum notatum Other: Desmodium incanum (see above)
Smith Creek Highway (CR 375). The ~12-mile segment from the south end of Site 1 (see below) north to Smith Creek (30.167183, -84.655476) has many areas that resemble SR 65 in showiness, although none of this segment seems as diverse with respect to native species. Much of this segment lies within the western edge of the Apalachicola National Forest (ANF), although not Site 1. While some native species occur in the mow zone, most occur in the moist swales and the drier back slopes to the wooded edge.
Of the four potential sites, the two showiest ones were selected: Site 1 on the south end of the 12-mile segment and Site 4 further north. However, much of this 12-mile segment has the potential to rival SR 65 in showiness and diversity given the predominance of native species and that most of the 12-mile segment lies within the ANF. It was recommended that from mid-February to late November Wakulla County should consider only regularly mowing a 6- to 9-ft strip, where possible, for this entire 12-mile segment, followed by a full ROW mowing in late November. As of September 26, 2014, the fall cleanup mowing had not occurred on this 12-mile segment.
Coreopsis floridana (Florida Tickseed) were locally abundant in moist areas along this 12-mile segment based on a random sampling by David Roddenberry in 2013 and Jeff Norcini in September 2014*; however, it’s quite possible that Coreopsis gladiata (Golden Tickseed) also occurs since it typically is more common in the panhandle than C. floridana.
Site 1. Mowing from March to at least late September 2014 has been limited to about an 8-ft strip adjacent to the edge of pavement.
North end: 30.090045, -84.536475; south end: 30.089436, -84.528070 Length: about 0.5 miles Habitat: ruderal on front slope, transitioning to a remnant native plant community from the moist ditch to the backslope; backslope to wooded edge appears to be a remnant native plant community comprised mainly of native flatwoods and bog species.
This site should be showy from April through October based on the diversity of showy wildflowers and grasses observed from spring to fall 2013, and if mowing is limited to the 6- to 9-ft strip from March to at least mid-November.
*NOTE: Much of this site was not nearly as showy on September 26, 2014 compared to early October 2013. The showiest displays of wildflowers may have occurred earlier as Coreopsis floridana was flowering a few weeks earlier than normal.
Amphicarpum muhlenbergianum or Panicum hemitomum, Dichanthelium sp., Dichondra carolinensis (north buffer only), Elephantopus sp., Eustachys sp. (north buffer only); Phyla nodiflora, Viola lanceolata
Other Species
Hydrocotyle sp. and Ludwigia sp. – not enough info to determine species, and hence nativity
Non-Native Species
Medicago sp. (M. lupulina and/or M. polymorpha)
Species that could Negatively Impact Aesthetics or Sustainability
Site Turfgrasses: Paspalum notatum (bahiagrass) Other: Hyptis mutabilis, Richardia sp. (R. scabra and/or R. brasiliensis)
North Buffer
Turfgrasses: Paspalum notatum Other: Desmodium incanum (A potential concern if an herbicide containing imazapic is used as imazapic could increase the spread of this mat forming species), Eupatorium capillifolium, Hyptis mutabilis, Paspalum urvillei
South Buffer
Turfgrasses: Paspalum notatum Other: Desmodium incanum (see above)
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September 26, 2014
Site 2. Mowing from March to at least late September 2014 has been limited to about an 8-ft strip adjacent to the edge of pavement, although the west side ROW has been substantially disturbed by large vehicles and/or machinery as shown in the image to the right. The impact of this disturbance on native vegetation and weeds will not be known for several months; however, it is hoped that the soil seed bank has a high enough percentage of native vegetation propagules (seeds, rhizomes, and tubers) to minimize any detrimental impacts, especially from Cyperus esculentus (Yellow Nutsedge). Cyperus esculentus can spread quickly, and it exudes allelopathic substances from the roots that can inhibit germination and growth of other species.
North end: 30.119108, -84.638917; south end: 30.117833, -84.638407 Length: about 500 ft Habitat: Ruderal near edge of pavement; transitioning to a remnant native plant community from the moist swale to the backslope; backslope to wooded edge appears to be a remnant native plant community comprised mainly of native flatwoods and bog species
This site should be showiest in April/May and September/October based on the diversity of showy wildflowers and grasses observed from spring to fall 2013, and if mowing is limited to the 6- to 9-ft strip from March to at least mid-November. Summer wildflower displays should improve.
Table 1. Scientific and common names of species mentioned in this report and/or the Management Plans. Type: WF = Wildflower; GC = Non-showy Groundcover; GR = Grass; SG=Sedge; SH=Shrub; SHH=Showy Shrub; V = Vine; WD = Weed (in the context of this project)
Scientific name Type Common name
Acmella oppositifolia var. repens WF Oppositeleaf Spotflower
Agalinis sp. WF False Foxglove
Aletris lutea WF Yellow Colicroot
Ambrosia artemisiifolia WD Common Ragweed
Amianthium muscaetoxicum GR Flypoison
Amphicarpum muhlenbergianum GR Maidencane
Andropogon glomeratus GR Bushy Bluestem
Andropogon virginicus GR Broomsedge Bluestem
Andropogon virginicus var. glaucus GR Chalky Bluestem