December 2011 Your levy in action Mother Nature’s news for summer La Niña’s good and bad news Perennial ryegrass evaluation DairyNZ Forage Value Index on its way Facts on fertiliser Purchasing the right product WAITING FOR THE RAIN Taking control when the big dry hits
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Transcript
December 2011
Your levy in action
Mother Nature’s news for summer
La Niña’s good and bad news
Perennial ryegrass evaluation
DairyNZ Forage Value Index on its way
Facts on fertiliser
Purchasing the right product
Waiting for the rainTaking control when the big dry hits
contents1 From the CEO
News in brief
2 Cover story – waiting for the rain
6 Managing dry conditions
8 Bruce Thorrold: DairyNZ view
10 Frequently asked questions about fert
13 Checklist for purchasing fertiliser
14 Organic trial findings
15 Myth busters: soluble fertilisers
16 Soil scientist Mike O’Connor
18 DairyNZ’s Forage Value Index
22 Summer management
23 Grazing for ryegrass persistence
26 Effluent design code of practice
27 Regional indicators for nutrients
28 Research farm profile: Tauhara Moana
30 News in brief
Hot & not
31 Regional focus
32 Regional update
Inside Dairy is the official magazine of DairyNZ Ltd. It is circulated among all New Zealand dairy farmers and industry organisations and professionals.
28
10 31
ISSN 1179-4916
Must-reads:
Fertiliser FAQs – page 10
Some of the most commonly asked questions about
fertiliser requirements, options and applications
have been answered by DairyNZ.
DairyNZ Forage Value Index – page 18
A new Forage Value Index is being developed
by DairyNZ and the New Zealand Plant Breeding
and Research Association (NZPBRA). It will enable
farmers to compare perennial ryegrass cultivars by
their expected profit.
On the cover: Morrinsville dairy farmer Eric Kolver monitors
pasture and weather conditions closely, to better manage
dry conditions.
2
We appreciate your feedback Email your comments to [email protected]
or call us on 0800 4 DairyNZ (0800 4 324 7969).
Alternatively, post to
Inside Dairy, Private Bag 3221, Hamilton 3240.
1InsideDairy
f rom the ceo
By the time you’re reading this,
the election will be over and we
should have a new government.
Instead of a Christmas wishlist, at DairyNZ we’ve got a wishlist of
things we’d like to see for farmers, from those in power. Here’s the
top four.
1. Keep agriculture out of the Emissions Trading Scheme. We
are committed to reducing greenhouse gases in dairying but
there is no point in knee-capping our biggest export earner
when none of our international competitors are similarly
penalising their farmers. Taxing New Zealand agriculture
on its emissions would simply add costs to our produce and
our overseas customers may go elsewhere. Until we have
genuine on-farm solutions it's a lose-lose situation.
2. Work with us on developing the National Policy Statement
on water. We’ve made some good progress in the last three
years working collaboratively with regional councils to solve
the issues together, and want to continue to be able to do so.
3. Develop a joined-up approach across government and
partner with industry on a joint investment plan in the
people capability area. Increasing the knowledge and skill
levels of those working in the industry is crucial to our
continued success.
4. Don’t delay the July 2012 introduction of NAIT, and include
sheep and other at-risk species as soon as possible. Having
an effective national system to identify and trace our
livestock will mean we can respond far more quickly to a
disease outbreak or food safety scare.
I’m pleased to say our discussions with LIC over the
recommendations of the Anderson Report on the national dairy
industry good database are progressing – it’s in the interests of us
all that we reach an agreement.
The global economy is facing uncertain times, with upheaval in
the European markets. New Zealand’s economy needs the earnings
from agriculture more than ever. Let’s hope the rain keeps coming,
but of course not to the extent it spoils your summer holiday!
As always, I welcome your feedback. You can contact me at
PS We’ve had great feedback on the Healthy Udder Tool which
went out with the October Inside Dairy. This time it’s for something
for the house, not the shed. It’s our Christmas cowbot – you can
find more of her relations at the website home of Rosie, our dairy
industry cowbassador rosiesworld.co.nz/funstuff
I’m taking the opportunity
to have my own column for
the final 2011 edition of Inside
Dairy, wrapping up what’s been
another very good year for
the organisation.
We are now halfway through our six-year levy period, and in
2014, every farmer who receives a milk company cheque will be
asked to vote on the continuation of the dairy industry levy that
funds DairyNZ’s work.
When DairyNZ was established, we undertook to have the
organisation independently audited twice, halfway through
the levy period, and again at the end. The half-year review was
conducted earlier this year by an Australian firm, Warwick Yates
and Associates. The full report can be found at
dairynz.co.nz/audit2011
In short, it found that:
• DairyNZ’s reporting and audit processes are rigorous and
ensure accountability and transparency
• DairyNZ’s senior management team has healthy levels of
professional communication and debate on a timely basis,
without the process being overly bureaucratic
• DairyNZ is a professionally run organisation that complies
with all governance principles.
The audit further highlighted the challenges facing the
industry, in particular, its environmental reputation. DairyNZ
management recognises the need for significant industry
collaboration to address these issues.
The auditor noted seven recommendations for DairyNZ
management to consider. It is, however, gratifying to note that
many of these recommendations are already being addressed as
part of DairyNZ’s management agenda.
We held our annual general meeting in Hamilton at the
beginning of November where the results of our directors’
elections were announced.
We had eight candidates for three positions. Directors Kevin
Ferris, Michael Spaans and I were all standing for re-election.
Michael and I were re-elected, along with Woodville farmer Ben
Allomes. I’d like to thank Kevin Ferris for his contribution to the
board in the last two years. He’s been involved and connected to
the heartland of New Zealand dairying and is always prepared to
encourage fellow farmers to focus on continually improving the
farming systems, particularly around sustainability matters.
I’d also like to welcome Ben to the DairyNZ Board. As a
former Sharemilker of the Year winner and president of Young
Farmers, he’s an outstanding younger farmer and I am sure he
will contribute much to DairyNZ in the future.
Wishing you all a very happy Christmas and a prosperous
New Year.
Hon. John Luxton
Chairman, DairyNZ
MESSAGE FROM THE CHAIR:WRAPPING UP A SUCCESSFUL YEAR
cover fea ture
dairynz.co.nz2
Waiting for the rain
3InsideDairy
Taking conTrol when The big dry hiTs
When the hills of Eric Kolver’s Morrinsville farm began showing
tell-tale signs of early dry conditions last November, he’d already
taken steps to be ahead of the game.
Eric had been closely monitoring pasture cover, rainfall, soil
moisture and the predicted La Niña weather pattern, so it came
as no surprise when action was required to ensure the 180-cow,
system three farm was still milking in the new year.
“On November 11 I saw there was a problem, I’d been
monitoring pasture covers every 10-15 days and growth rates had
started to drop,” says Eric. “I decided to develop a plan.”
A variable order sharemilker for James and Jane Thomas, and
a former Dexcel senior scientist, Eric says identifying the problem
early and making a decision is key.
“On the 11th we contracted PKE early, to get good prices.
We bought in 45 tonnes, twice what we normally use. We were
basically planning for a worst case scenario – what if it’s still dry in
February?” says Eric.
“That PKE was fed out from mid-November to February at
2-4.5kg DM/cow/day. We also aimed to lengthen out the round
from 21 days to 25 days.
“Being proactive is so important in any drought but an early
drought is different and you need to keep as many cows milking
as possible, because there’s so much of the season left.
“In hindsight, the feed we bought in was very economical to
keep them milking. Contracting it early helped. We felt in control,
we had feed in the shed.”
The 75ha farm (57ha milking platform) had 40mm rain in
October and 32mm in November. Come mid-December, average
pasture covers were heading down to 1500kg DM/ha. Eric began to
weigh up the options – dry off, milk once-a-day or every 18 hours.
(cont'd pg 4)
Waiting for the rain
^ Variable order sharemilker Eric Kolver.
dairynz.co.nz4
(cont'd from pg 3)
“When I did the figures it was as good if not better to dry off
a few of the light heifers. So on December 16 we sent 15 heifers,
8 percent of the herd, out of the region for grazing so they’d
come back in good condition for next season,” says Eric.
“We were doing a bit of everything – bringing in feed,
lengthening out the round and reducing demand. We had also
sown 2.6ha of turnips in October, which eventually gave six
weeks of feed in January/February.”
On December 20, around 93mm rain provided some relief for
pasture. On December 22, eight empty or late calving cows (4
percent of the herd) were culled to reduce demand even further.
January eventually clocked up 233mm rain, most of it late in
the month. Silage was made in February and the herd eventually
milked right through until May.
“It does not last forever, we had less than 1800kg DM/ha
pasture cover for six weeks, but it seems like a long time when
you’re in it,” says Eric. “Extending the round, holding it and
having supplement going in really helps.
“You can be in control. You just have to get the information
and make the best decision you can, with the information
at hand.”
Eric says attending local discussion groups is invaluable during
these types of weather events. “It’s good to get the big picture,
see what other people are doing. That motivates you to get into
action too.”
16 hour milking success
Over the fence from Eric, lower order sharemilker Ben Gray
gave 16 hour milking a go when grass started to dry out
last December.
It worked out well – both for keeping weight on the 205
cow herd and his own lifestyle, while still achieving a record
season for production.
“It started looking like a hard summer so I decided to jump
into 16 hour milkings early rather than late, to save weight
on the girls,” says Ben. “I really did it to fatten the cows and
make sure they were carrying a bit more weight for calving.
“I might do it again this year, even just to keep weight on.”
Ben switched from twice-a-day milking to 16-hour milking
in December, doing a normal morning milking, a 8-9pm
evening milking the same day, then a lunchtime milking the
next day.
“I really enjoyed it, it gave me more time to do other
things. I actually continued it right through to dry off in April
and still did a record season, 75,000kg MS.”
Along with the 16-hour milking, Ben also fed 3ha chicory,
turnips late summer and PKE. He also maintains a
reasonably slow round.
5InsideDairy
once-a-day milking as a
summer managemenT Tool
BY CLAIRE PHYN / DairyNZ scientist
Once-a-day (OAD) milking can be used in dry summers to
help protect the next season’s production and reproduction
by getting cows to body condition score (BCS) 5.0-5.5 by
calving, whilst achieving reasonable production for the rest of
the current season.
The key things to consider are:
• Weigh up all nominated options, including early culling,
feeding supplements or drying cows off. Removing known
culls early provides the remaining cows with more feed
for milk production and cow condition
• All of the herd, or just the younger and thinner cows, can
be milked OAD to achieve longer lactations while helping
to reach target BCS. Cows milked OAD during late
lactation are able to gain (or maintain) condition better
than cows milked twice-a-day (TAD). They may, therefore,
achieve more days in milk because they do not need to be
dried off as early to meet calving BCS of 5.0 for mixed-
age cows and 5.5 for first and second calvers
• Switching to OAD decreases daily milksolids yields by
about 10-20 percent and is additional to any production
drop due to lower feed quantity or quality. However,
between 60-70 percent of the season’s milk has already
been produced. Therefore, the potential loss equates to
about 3-8 percent of a cow’s total milksolids production
• The actual effect on the total season’s production will
depend on lactation length – longer lactations can be
achieved than if cows had remained on TAD. This gives
the farm options to milk for longer if pasture growth
improves in the autumn
• Daily production losses may be less than 10 percent if
OAD reduces pressure on the cows, because they do
not have to walk to the shed in the hot afternoon
sun (particularly if long distances or hilly terrain is
usually covered)
• OAD also takes the pressure off people, enabling more
time for other activities (e.g. monitoring pasture covers
and cow BCS or feeding out), or an improved lifestyle
• Research indicates that OAD decreases feed intakes by
about 10 percent (i.e. by 1-1.5kg DM/cow/day when TAD
milked cows are eating about 15kg DM/cow/day)
• Bulk somatic cell count (SCC) needs to be able to
accommodate a doubling in value following the switch to
OAD. Cows identified with mastitis or high SCC should be
either dried off or milked in a TAD herd to keep bulk SCC
under control
• Milking three times in two days (or 16-18 hour milking
intervals) is another option. This strategy produces less
of a drop in production, but is not as effective as OAD in
achieving target BCS.
^ Eric Kolver
dairynz.co.nz6
drought management
Managing the Achilles' heel – summertime It’s late October and it’s pelting down. Right now there’s more than
enough grass to go around. But Bay of Plenty farm owner John
Campbell and sharemilkers, son-in-law Gregg Young and wife Natalie,
know exactly what their tactics will be if – or perhaps when – they face
dry conditions this summer.
“Every farm has its strengths and weaknesses,” says
Whakatane dairy farmer John Campbell. “This is a good farm in
autumn, good for growing grass in winter and is a strong spring
farm. Its Achilles heel is the summertime.”
The 232ha (effective) farm milks 840 crossbred cows on
pumice soil with low water holding capacity and where rainfall
is very unpredictable during summer. John knows the farm
well – he bought the original 93ha in 1983 and has added
neighbouring properties along the way.
Some neighbours have opted for irrigation, but logistical
access to water and the financials have deterred John. In fact,
the farm has performed in a dry summer without irrigation. For
the 2009/10 season the farm profit was ranked sixth of 23 farms
benchmarked using DairyBase in the area and was the second
highest for farms without irrigation.
The farm team has three key tactics for dry conditions – early
purchase of grass silage and contract PKE; drop cow numbers
early and put the young/light herd on once-a-day (OAD) milking.
“We purchase some 300t DM of grass silage every October – I
call it my irrigation,” says John.
“We put the younger cows on OAD, walk them in the morning
when it’s cool and feed supplement throughout. We don’t like
stripping weight off,” says John. “We walk cows a long way, if
it’s 2km to the shed in summer, we have basically walked the
milk out of them anyway.”
John's experience and risk management philosophy drives
proactive decision-making.
> Whakatane farmer John Campbell.
7InsideDairy
Getting in early
To help prepare for dry conditions, John and Gregg will harvest
any feed surplus available.
“We’ll just do light cuts so the paddock is back in the round
while the grass is still growing, usually in October and early
November to maintain quality,” says Gregg. “If it pops up, we
will do it, but we don’t go hunting for it.”
“There is always a feed pinch here at some point over summer,
so we have to plan for it,” says John.
In Whakatane, November has been dry for three of the last
five years. Gregg and John opt to fill any feed gap with PKE and
silage if necessary.
The farm was heavily affected by a severe drought in 2009/10.
“That year it was good until November, then it got dry and it
didn’t improve. That was the worst we have had,” says John.
The 2009/10 drought
As an impending dry spell loomed in mid-November, silage
was fed out to maintain cow condition. Little rain by December
meant the young cows and those in lighter condition (around
375 cows) were OAD milking just prior to Christmas.
The team also began looking at cows to be culled or sent
off-farm. “Any cows we could get rid of, we did,” says John.
“Initially any possible culls are cows that are not performing or
any older ones.”
Come mid-December, 15 cows were culled and later that
month 50 went to grazing in the South Waikato and 30 to the
South Island.
“In January, when the pressure was on, we culled every
cow we thought wouldn’t be here next season while being
conservative and allowing for 8 percent empties although empty
rate has not been more than 6 percent over the last few years.”
Mid-January saw another 85 cows culled and 35 more in
February/March (mostly empties).
Once it rained, fertiliser was used to get grass growing but
a slower rotation maintained and supplement is fed out until
pasture cover increased. Eventually, 335 were dried off on March
24 and the remaining 335 on April 14.
Supplement use
Throughout the 2009/10 drought, silage purchased was fed
out, along with PKE. In February maize silage, some grown
on run-off land, was used to extend the round, while keeping
weight on the cows.
“I put my hand in my pocket and bought in hay too. You
need to get weight on them before calving, to dry off at a
good condition score, so you have to do something about it,”
says John.
Last season chicory was grown on the effluent area, with an
excellent result. This year they are increasing the amount of
summer crop to 12ha chicory and 12ha turnips. These are grown
on under-performing paddocks affected heavily by the very wet
autumn and winter. If these paddocks were not put into crops
they would have contributed little to the season.
“I don’t want to fall into a hole and then start panicking. I
don’t want to have to think ‘can I feed these cows’. I like to have
feed on hand and not be buying it when in a feed pinch. The
biggest thing is to make a decision – I might not always be right,
but at least I have done something on the day.”
Key tactics to drought management with aim
to minimise BCS loss:
• Annual purchase/harvest grass silage in October for
the summer: 400-450kg DM/cow
• Contract PKE early
• Put the young/light herd on OAD – by Christmas if dry
• Drop cow numbers early – January.
“I don’t want to fall into a hole and then start panicking. I don’t want to have to think
‘can I feed these cows'."
^ The team: John Campbell, Jordan Macdonald (2IC),
Harry Brown (assistant manager), Gregg Young
(sharemilker) and Justin Eagle (farm assistant).
dairynz.co.nz8
da i r ynz v iew
The biological farming debateI spent a day last month at the
first National Biological Farming
Conference. You might have seen
me reported as saying that
DairyNZ welcomed the debate
about different ways of farming
and nutrient management.
Well we do welcome the debate – in part because fertiliser
management has fallen off the radar lately as more pressing issues
such as effluent and pasture persistency have taken centre stage.
By opening this topic up to discussion we can take another
look at the key principles of fertiliser management, keep updated
on any new developments in science and evaluate whether we
need to make any changes on-farm because of changes to
the system.
What I have yet to see reported were some of the other
comments I made about biological farming and
fertiliser management.
All dairy farming in New Zealand is based on biology. The vast
majority of New Zealand farmers, scientists and agri-business
people acknowledge and support the importance of soil biology
and physical structure in efficient and sustainable farming.
The term ‘biological farming’ has been adopted as a generic
brand by companies marketing products and services to farmers.
It seems to be defined as a system that aims to build soil biology
with an expectation this will lead to good results – which poses
the question, will the products and practises advocated and sold
achieve these results?
To me, there seems to be three main ideas or product groups
in biological farming.
The first is an idea to reduce inputs of soluble fertilisers. For
many high feed input farmers, a nutrient budget would show
that reducing the use of fertiliser is the right response to balance
out the amount of nutrient coming in the gate in feed. We have
seen farms that need no additional phosphate or potash inputs.
This includes reducing urea use.
Biological farmers comment they have reduced urea use
and seen clover content increase and pastures improve. These
observations don’t require a new principle of soil science to
explain – high N inputs will suppress clover (and some of these
farmers have been using over 200kg N/ha along with bought in
feed), and this will be made worse if pasture management is lax
with high residuals.
So taking some N fertiliser out of the system and better
managing pasture will produce results – possibly even more milk
9InsideDairy
DairyNZ strategy
and investment
leader - productivity,
Dr Bruce Thorrold >
production with less N input, as pasture quality improves through
management. And lower N inputs will lead to lower N leaching –
but simply on the basis of the reduced N inputs.
So in my view, all farmers should be examining their use of
solid fertiliser – but on the basis of nutrient budgets and nutrient
use efficiency benchmarks – not on the basis of an argument
that soluble fertiliser damages soil ecology.
Fert recommendations
The second idea is that fertiliser recommendations based
on balancing base saturation will give better results than
recommendations based on ensuring no nutrient is limiting.
This is a long-running debate among international soil and
fertiliser experts. From what I have read, it is my opinion that the
‘law of the minimum’ effect is a more certain and cost-effective
way of optimising fertiliser inputs and pasture growth.
Farmers have made the observation that changing their
fertiliser programme has led to improved soil structure and
water infiltration. While this may also be due to a focus on
preventing pugging, it is an area where some further work may
be warranted.
The third idea is that by using products claimed to enhance the
soil’s biological activity, farmers can produce more product with
lower inputs, and have healthier animals and a better soil. Many
of the products promoted utilise comparatively small amounts of
materials including rock minerals, seawater, fish by-products and
humates. Low rates of standard fertilisers are sometimes used.
There is no evidence that this will happen. This is an old
argument being recycled in a new brand. Many hundreds of
experiments have been done in New Zealand to measure the
links between the ‘active ingredients’ in fertilisers and pasture
growth and animal performance.
Research
Studies have been conducted under grazing and pasture
mowing, and include long-term studies running for over 30
years. Many different types of products have been tested
alongside widely used products such as superphosphate, potash
and urea. This research has helped calibrate soil and herbage
tests for New Zealand conditions.
This work shows that the response to any input or ‘active
ingredient’ is proportional to the amount applied. Research has
shown that nutrients (P, K, S, N, Mg etc) lime and gibberelic acid
are active ingredients.
The effectiveness of products such as DAP slurries, fine lime,
seaweed extracts, di-calcic phosphate, serpentine and compost
teas can be predicted from the amount of nutrients and lime
contained by these products. There is no evidence that fine-
grinding, foliar application, slurries or biological material in these
products improves their effectiveness over and above the active
ingredients applied.
I’m very aware of the interest in biological farming and the
reports from farmers who believe they are getting good results.
We are attempting to work with farmer advocates of biological
farming to test their observations that they are getting responses
much greater than can be explained by DairyNZ’s current view of
soil and fertiliser science.
These results will be reported to farmers as they emerge – but
right now, my view is that when we see farmers using biological
principles and getting good results – what we see is good
farmers getting good results. But it is a consequence of good
nutrient management, good pasture and feed management and
a focus on protecting soils from pugging.
I believe that farmers will get the best value for money from
their expenditure by following current advice based on soil,
herbage and animal testing.
Frequently asked fertiliser questions
Calcium, lime, liquid or finely ground...
Some of your fert questions answered
dairynz.co.nz10
fe r t i l i se r FAQ
The extension team at DairyNZ is frequently
asked about fertiliser requirements, options
and application. Below is a summary of key
questions and advice.
Q: Is the response from liquid fertiliser or finely ground fertiliser better than conventional solid fertiliser, when the same amount of nutrient is applied per hectare?
A: No. Many trials over the years have shown it is the amount of nutrient applied that matters. The total response to the nutrient, whether it be nitrogen, phosphate or lime, is the same over time regardless of whether the nutrient is applied as a liquid, finely ground or in a more coarse form.
The response time from the nutrient may differ, with a quicker response to liquid and finely ground products. However, the total response is the same when measured over time. Some products claim better responses where the response is measured over a shorter time period and the total long-term response from the more coarsely ground product is not measured.
Q: Is urea destroying organic matter in soils?
A: No. Pastoral grazing systems build up high levels of organic matter. Anything that stimulates plant growth (e.g. fertilisers P, K, S, N) increase the amount of litter going back into the soils, as well as what the grazing animal adds. These activities stimulate microbial activity. Therefore urea (nitrogen) does not destroy organic matter and may even assist in building organic matter when applied to grazed pastures. If high annual N rates are used, lime maybe required to maintain soil pH (need about 1kg lime per kg of urea or 3kg of lime per kg sulphate of ammonia).
However, recent research indicates that soil carbon has declined by about 10 percent over 20 years with intensive dairying. The reasons for this are uncertain but could include decreased root growth relative to shoot growth, and increased level of pasture utilisation with less return of plant residues to soil. It is unknown whether increased N fertiliser use might contribute to this. Nevertheless, levels of carbon in New Zealand pastoral soils are much greater than those in cropping soils and in many overseas pastoral soils.
Q: Should we be applying more calcium (Ca)?
A: Most New Zealand soils have an abundant supply of calcium as the soils are derived from parent material that is rich in calcium. Ca deficiency in New Zealand soils is unheard of. The confusion comes with the belief that Ca increases soil pH. It is not the Ca that increases pH but the alkali content of
the product, the cheapest forms being carbonate applied as either limestone (calcium carbonate) or as dolomite (calcium magnesium carbonate).
Lime increases pasture production because it increases soil pH not because it increases Ca. In addition, superphosphate contains 20 percent Ca and this represents a significant input to soils. Calcium is required by the cow, however applying it to soil does not improve the calcium supply to the cow. If applied before calving it prevents the cow from mobilising calcium and can
induce milk fever.
Q: How does lime benefit soils and pasture production?
A: Liming benefits the soils in several ways, through increasing pH. One of the most important benefits is that it stimulates soil biological activity and increases the availability of soil N, particularly in the pH range 5.5-6.0. This is why limed soils appear greener, as the lime increases soil nitrogen, in the same way N fertiliser does.
Liming also reduces the availability of soluble aluminium and manganese which are toxic to plants at low soil pH (e.g. less than about 5.5). If the pH is lifted above 6.5 on coarse, textured soils it can result in a zinc or manganese deficiency by reducing their availability. Liming can also increase the availability of molybdenum and the wettability of a soil.
Q: Do humates improve soil organic matter (OM)?
A: Soils contain between 60t (soils in the McKenzie basin) to 350t (volcanic ash soils in Taranaki and peat soils in Waikato) of organic matter, with most dairy farms around 200-300t OM/ha. If say 60kg/ha of humate was applied, this would add only 0.2-0.3 percent organic matter to the soil and therefore is unlikely to have any effect. The claim that they stimulate soil microbes is very unlikely, given how little is applied.
Q: Overseer takes into account all major nutrients used on the farm, including those bought on in supplements and recycled in dairy effluent. How evenly are these nutrients spread over the farm and does Overseer underestimate the nutrients required on parts of the farm?
A: Nutrients are spread around in urine and dung patches which can cover around 25 percent of the area in a year. Therefore, it takes a number of years for even coverage. Overseer accounts for the longer-term effect of the nutrient recycling from this supplementary feed use by assuming even coverage eventually occurs. But it does account for the component that goes off the farm in the extra milk and the transfer to lanes and the effluent system.
11InsideDairy
(cont'd pg 12)
dairynz.co.nz12
Q: Why is it the results of soil tests from laboratories outside New Zealand (e.g. United States) are disregarded by some fertiliser consultants?
A: Regardless of where the laboratory is, what matters is that the tests are calibrated for New Zealand pastoral soils. Calibration means that a relationship needs to be established between the test and some other factor, generally pasture production. This relationship will allow to identify levels of soil test when soil properties are limiting (or excessive) for pasture or animal performance. For this reason, any soil or herbage tests not calibrated by field trials for New Zealand soils and pastures, should not be used. This caution applies to most tests from overseas labs and some tests from New Zealand labs.
Q: In early spring, there are occasions when sulphur is limiting. Can the application of finely ground elemental sulphur (S) be as effective in meeting this deficit as applying sulphur in the sulphate form?
A: For the plant to uptake sulphur it must be oxidised to plant-available sulphate S i.e. the plant cannot take up elemental S. The oxidation process is performed by microbes (bugs) in the soil and the rate of conversion is driven by temperature, moisture
and the particle size of the elemental S. Therefore, if sulphate S is deficient in early spring because the conversion from elemental S residues or soil organic matter is too slow due to temperature, finely ground elemental S will not be as effective as sulphate S. Applying elementals in the previous autumn can be effective for limiting the risk of S in early spring.
Q: What is the highest response possible from applying nitrogen and what is the maximum daily uptake of N/day?
A: In general, the highest N responses have been measured when grass is fastest growing in late-spring and can be about 20kg DM/kg N applied. At this time, when grass is growing rapidly, its roots can absorb up to 4kg N/ha/day.
Q: Is the Brix test useful for determining nutrient requirements or feed quality for animals?
A: The Brix test measures the amount of soluble sugars in a plant. This is very useful to fruit and vegetable growers. However, it has no value for pasture as the cows can utilise various forms of plant carbohydrate and the Brix test only measures a small amount of the structural and non- structural carbohydrate.
(cont'd from pg 11)
Article references: Dr A Roberts, Ravensdown; Dr A Mackay, AgResearch; Dr B Thorrold, DairyNZ; Dr S Ledgard, AgResearch; Dr D Edmeades, AgKnowledge; Dr A Morton, Ballance; Dr M Scarsbrook, DairyNZ; R Brazendale, DairyNZ; P Hedley, DairyNZ.
13InsideDairy
How to purchase the right fertiliser
fe r t check l i s t
Using the right product to achieve the best results, at least cost, is the primary objective of fertiliser. The following checklist helps ask the right questions when weighing up whether a particular fertiliser product is appropriate for your farm.
What are the recommendations based on?
What is the nutrient content of the product (kg nutrient/tonne)?
Has the nutrient content been determined from independent testing? Yes No
Have soil and plant tests been calibrated for New Zealand soils and pastures? Yes No/overseas
Does the product supply the nutrients required for your farm?
Only 16 nutrients are required for plants. Refer to DairyNZ Farmfact: Plant nutrition Yes No
What is the cost per kg nutrient and how does it compare to the cost of other
fertiliser products?
Refer to the DairyNZ Nutrient
Cost Calculator
If the product is being promoted as having a liming effect – what is the percentage of
carbonate in the product and how does this compare to lime?
Refer to the DairyNZ Nutrient
Cost Calculator
Is the fertiliser Fertmark registered? Yes No
Is the biological activity in your soil limiting pasture production?
The biological activity on most New Zealand soils is good, with the exception of some cropping
soils. If your soil has good physical properties, biological activity will be high.
Yes No
Is there scientific, independently peer-reviewed evidence? Yes No
Are the results expressed as an absolute comparison rather than a marginal comparison?
e.g. ‘Control = 300kg DM, Product = 350kg DM’ as opposed to ‘17% more grass’. Yes No
Do they know the detailed reasoning behind how and why this product works? Yes No
What are their qualifications? Do they have any qualifications or a background in
soil science? Yes No
Do they have experience in fertiliser use and nutrient budgeting for New Zealand soils? Yes No
Have they completed the Fertiliser and Lime Research Centre’s (FLRC) Sustainable
Nutrient Management Course? Yes No
If the product is being promoted as having benefits other than supplying nutrients, such as soil conditioning effects, improved biological
activity or making more nutrients available:
Ask about the salesperson...
Remember
• If unsure about any products or reasoning behind the products please seek advice
• And: if it sounds too good to be true, it probably is!
References
• 1Refer to DairyNZ Farmfact: Nitrogen – the principles of applying nitrogen fertiliser to pasture. 2Refer to DairyNZ Farmfact: determining fertiliser nutrient requirements.
• The DairyNZ Nutrient Cost Calculator can be found at dairynz.co.nz/nutrientcostcalculator
• DairyNZ Farmfacts can be found at dairynz.co.nz/farmfacts
• Fertiliser Use on New Zealand Dairy Farms (Fert Research)
Current soil
nutrient status,
production and
other inputs
(supplements).1
Base saturation
or cation
exchange
capacity.2
Ask about the product...
Organic trial findings relevant to all farmers
organ ic s v s convent ion
dairynz.co.nz14
BY DR DAVID HORNE | Massey University, soil scientist
Massey University has run a farm systems trial for the past ten
years comparing organic and conventional production.
The guiding principles have been to provide sufficient nutrients
to meet plant demand for the targeted production, while not
over-supplying nutrients. At the project’s launch 10 years ago,
the mean Olsen P value on the organic farmlet was 47.
This number was considered too large as the value was greater
than the ‘biological
optimum’ (i.e. in the range
of 30 to 40) and it posed
an environmental risk of
phosphate runoff. An
Olsen P of 47 would also
be a major challenge to
maintain, in a cost-effective manner, given the relatively narrow
range of certified organic fertilisers.
To stage a reduction of Olsen P levels, initially only small
quantities of phosphate (P) fertiliser were applied until a mean
Olsen P of 35 was reached. Maintenance P has since
been applied.
The organic farmlet has not grown as much grass (an average
of 9.85 t/ha) as the conventional farmlet (an average of 11.25 t/
ha), much of this difference can be accounted for in differences
in nitrogen (N) inputs in both fertiliser and imported feed.
These differences also accounted for the organic farmlet
leaching less N than the conventional farmlet.
On the organic farmlet, a range of fertilisers and soil
conditioners have been used, with very mixed success. To be
perfectly frank, not all products evaluated proved to be effective.
As some of these products contain only very small quantities of
nutrients, their inability to provide adequate plant nutrition is not
surprising. Organic, and for that matter conventional, farmers
need to proceed with caution when contemplating the use of
‘alternative’ fertilisers.
Osflo, a chicken-based compost has been applied to the
organic farmlet for the last three or so years. This product has
the advantage of being a
nitrogen source.
When spread at a rate
of a little under 2t/ha,
then 68kg N/ha and 28kg
P/ha, are applied along
with other nutrients. This
is a match with the maintenance P requirement for the organic
farmlet, as calculated using Overseer.
A question often asked is ‘are we simply trading on or
mining the P reserves that had accumulated under conventional
management before conversion to organic production?’. This is a
very real risk that organic producers need to guard against.
Through the use of soil testing soil nutrient status has been
maintained on organic farms by using sufficient plant-
available nutrients.
In other words, providing there are adequate nutrients in the
fertiliser, they are plant available and that the fertiliser is cost-
competitive, the nutrient source per se is not important.
Of course soil quality is much more than just Olsen P, as in this
example, and is about all of the nutrients a plant needs as well as
soil biological and physical properties.
"In other words, providing there are adequate
nutrients in the fertiliser, they are plant available
and that the fertiliser is cost-competitive, the
nutrient source per se is not important."
cover fea ture
15InsideDairy
Epigeic: L. rubellus
Endogeic: A. caliginosa
Anecic: A.longa
BUSTED:
THE MYTH:
Soluble fertilisers destroy the life in soils
No! Application of soluble fertilisers to maintain soil fertility
will not destroy soil life.
Some people claim that soluble fertilisers, such as urea and
superphosphate, kill earthworms.
However the application of soluble fertilisers to maintain soil
fertility will not destroy soil life, but rather it ensures a continued
food supply to earthworms. Management practices that limit soil
damage in winter is the important factor in sustaining a healthy
earthworm population.
Earthworm numbers generally increase with applications
of soluble fertilisers, as the application of fertiliser stimulates
pasture growth, increasing the food available to earthworms1.
Earthworms are primary decomposers feeding on organic
matter, such as dead plant material and cow dung. As the
quantity and quality of organic matter increases, so does
earthworm abundance.
For example, a sheep grazed hill country pasture receiving
375kg superphosphate/ha/yr since 1980 had earthworm
abundance in excess of 1000m2, double that of a pasture that
had received no fertiliser in 26 years2.
Earthworms are at their most active in the winter and early
spring. During the winter months when soils are wet, earthworms
are vulnerable to livestock treading damage. Pastures damaged
by livestock treading can have reduced earthworm numbers3.
There is evidence to suggest that if present anecic
earthworms, which feed on organic matter at the soil surface but
live at depth (see figure one), may be more competitive in
dairy systems than epigeic earthworms which live near the
soil surface4.
Earthworms in New Zealand pastoral systems arrived
accidentally with the European settlers and hence have a
patchy distribution.
There are three types of earthworm which can be distinguished
and in an ideal soil all three types of earthworm should be
“There’s been a lot made of the impact nitrogen and
phosphorus losses have on our waterways and some people have
proposed that regulations are put in place to reduce them.
“It makes sense to keep our nutrients in the root zone and
convert them into feed. We’ll be taking a farm systems approach
to assessing some strategies to optimise nutrient use and
reduce leaching.”
Lower North Island Consulting Officers
Regional Leader Scott Ridsdale 027 499 9020
Rangitikei Scott Ridsdale 027 499 9020
Wairarapa/Tararua Leo Hendrikse 021 286 4346
Hawke’s Bay/Northern Manawatu
Sean McCarthy 021 222 9023
Southern Manawatu/ Horowhenua
Abby Hull 021 244 3428
33InsideDairy
Canterbury/North Otago Consulting Officers
Regional Leader Virginia Serra 021 932 515
South Canterbury/North Otago Chrissy Williams 021 227 6476
Mid Canterbury Leighton Parker 021 287 7059
North Canterbury Kim Reid 021 246 2775
Eastern Canterbury Juliette Lee 021 323 834
CANTERBURY/NORTH OTAGO
The arrival of South Canterbury/North Otago consulting officer
Chrissy Williams has bolstered the regional team’s numbers.
She fills a new position created to cater to the increased demand
generated by new conversions and the expansion of the dairy
industry in the area.
Chrissy comes to DairyNZ from AgITO where she reviewed and
developed learning programmes, resources and assessments for
agricultural training. Prior to that, for nearly 10 years she was a
senior agricultural tutor for Agribusiness Training.
She has also farmed in South Canterbury for more than 10
years, first in sheep and beef before converting to dairy.
Canterbury/North Otago regional leader Virginia Serra says
Chrissy’s experience brings an excellent mix to the role of
consulting officer.
“Adding to this she lives locally in the Waimate area so she
knows the area and the local farming community,” says Virginia.
Caring for every drop
New technology is improving the way dairy farmers irrigate
Demand on water resources nationally and regionally is continuing to grow
Water efficient practices are more relevant than ever
The financial and farm incentives to use water effectively are significant.
Five dairy farmers have shared their stories about how they use water resources well, thanks to technology, innovation, management, investment and experience.Two industry specialists also discuss sustainable practices and the way forward for irrigation. See what they say at dairynz.co.nz/irrigation
Spread the word – we’re responsible with water –
encourage your mates to view the clips at dairynz.co.nz/irrigation