Welcome to the Grassland Agronomy Update from Dow AgroSciences.
These regular technical notes are a seasonal commentary to help those interested in improving grassland productivity on dairy, beef, sheep & equestrian enterprises.
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- Target docks after silage
- Leystar on maize
- Spray thistles in May/June
- Dose rates and perennial weeds
- Spot treat with GrazonPro
- Right time to spray buttercups
- Use the Grassland APP for 24/7 support
- Dow AgroSciences show calendar
Target docks after silage
You need 3 weeks before cutting to spray Doxstar®Pro to enable it to fully translocate down into the dock roots. Where that window is not available plan to spray around two weeks after cutting instead.
The re-growth will have fresh green leaves and all at a similar stage, ideal for taking up a translocated herbicide. There will be less grass too making it easier to hit the target plants.
DoxstarPro gives good control of both broadleaved and curled docks. Apply at full dose rate of 2 L/ha in a water volume of 300 L/ha, unless air inclusion nozzles are being used, when the water volume can be reduced to 200 L/ha.
DoxstarPro is very safe to grass – recent market research carried out by Dow AgroSciences shows this is still top of the concerns for grassland farmers who spray herbicides.
Leystar on maize
New Leystar® has approval for post-emergence weed control in maize
Leystar combines clopyralid, fluroxypyr and new active for maize florasulam making it a very wide broad spectrum herbicide.
It should be applied when the forage maize is between the three and six leaf stage and before the crop is over 20 cm tall. It must not be applied once the buttress roots have started to develop on the first node.
Annual weeds that will be controlled include:
- Black nightshade
- Black bindweed
- Fat hen
Leystar will be an ideal partner in a program where pendimethalin is used.
Find more information on our Leystar Technical Information sheet.
Spray thistles in May/June
May/June is the time to spray thistles. Thistles tolerate dry conditions and will outcompete grass for any residual moisture. They prevent animals grazing all the grass in a field and are thought to help spread orf, a highly contagious viral disease of lambs and ewes.
The virus lives in the surface of the skin, but infection gets going once the skin is scratched by lambs grazing too close to thistles.
Affected ewes often develop mastitis. Infected lambs do not grow as quickly as healthy lambs, and they take longer to finish and market.
Topping thistles gives only temporary reprieve, especially with creeping thistles as they produce more stems from buds running below ground after cutting.
Options for spraying thistles
- Where thistles dominate, spray with Thistlex® using a tractor mounted or self-propelled sprayer. Thistlex also controls nettles.
- If the area taken by the thistles is less than 5%, spot treat with Grazon®Pro.
- If a broader range of weeds is involved, use the Pas·Tor® Agronomy Pack.
All these products will take out all species of thistles, such as Spear, Creeping or Marsh. Tackling them now reduces the amount of new plants that will germinate from seed this year.
Dose rates and perennial weeds
Dose rates on products are set using the criteria minimum effective dose. Reducing a dose rate particularly on perennial weeds is likely to result in poor weed control and survival.
Adjuvants can have complimentary activity e.g. drift retardence or limiting the effect of herbicide lock up in hard water areas but adjuvants are not a substitute for dose when targeting perennial weeds.
When adjuvants are used on crops destined for human or animal consumption, residues data must be submitted, showing the effects of the adjuvant on pesticide residue levels.
No residues data will be required where the adjuvant is used with a pesticide half or less than half the approved rate of the pesticide. Reducing the rate by this level and including an adjuvant is also false economy. The effect on the target weeds will be significantly reduced from spraying at the full rate on its own. Further lower rates leads to more incidences of repeat spraying which is not good for the environment and with many grassland sprays being applied by a contractor, unnecessary cost.
Spot treat with GrazonPro
There is really only one option for spot spraying in grassland and that’s Grazon®Pro. There is a need to be able to control small areas of docks, thistles, nettles and other weeds by hand, for example around gateways and water troughs. It is also more cost effective than a boom spray where weed populations are below 5%.
- GrazonPro contains 60 g/litre of clopyralid + 240 g/litre of triclopyr
- Excellent control of broadleaved dock, curled dock, creeping thistle, spear thistle and common nettle and a large range of other weeds
- Fast acting and translocates down to the roots
- Animals can be re-introduced after only seven days (not if ragwort is present)
- Rainfast in two hours
- Very safe to grass
- Good value for money – 16 knapsacks from each litre of product when mixed in 10 litre batches
- Comes with free measuring beaker
GrazonPro is for professional use and can only be used by suitably qualified people who hold a PA1 and PA6 certificate.
Right time to spray buttercups
Best levels of control are achieved before flowering. If you spray when they are in flower you can still get good control but not to the same level as if sprayed earlier.
Envy® – our new solution for weeds typically found in pastures which receive minimal nitrogen, controls both creeping and meadow buttercups, daisies and dandelions and is also pretty effective on plantains.
These weeds will smother grass and limit the provision of forage to grazing animals. Envy contains florasulam + fluroxypyr, it has no manure management restrictions after use – so ideal to use in pony paddocks. Its short stock withdrawal period of just 7 days makes planning in its use much easier then phenoxy based options which require a 14 day stock withdrawal period.
Use the Dow AgroSciences Grassland APP for 24/7 support
Use the Dow AgroSciences Grassland APP for 24/7 support and to access product labels, product technical sheets and our FAQ database at any time.
If the App is already downloaded, please ensure the latest version is being used.
Q. How does the Pas·Tor Agronomy pack compare to PastorPro?
A. One Pas·Tor® Agronomy Pack will treat 2 hectares and give the same level of control that Pastor®Pro would do if it was applied at 3.0 L/ha.
Q. Can I use Envy through a knapsack?
A. No. Its use in this way is not supported by Dow AgroSciences. The only product we have for knapsack use in established grassland is GrazonPro which should cover all needs.
The technical team from Dow AgroSciences will be out and about at many shows and events this summer, talking to farmers and agronomists and answering questions on how to tackle weed problems in their fields.
Catch the team at:
|May||24th & 25th||Grassland & Muck||Stoneleigh Park, Warwickshire|
|May||31st||NSA Highland Sheep||Strathpeffer, Ross-shire|
|June||7th||NSA North Sheep||Tow Law, County Durham|
|June||8th||Scottish Beef Event||Earlston, Berwickshire|
|June||20th||NSA Sheep South West||Tiverton, Devon|
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DoxstarPro contains fluroxypyr and triclopyr
Envy contains fluroxypyr and florasulam
Forefront T contains aminopyralid and triclopyr
GrazonPro contains clopyralid and triclopyr
Leystar contains fluroxypyr, clopyralid and florasulam
PastorPro contains clopyralid, fluroxypyr and triclopyr
Pas·Tor Agronomy Pack contains clopyralid, fluroxypyr and triclopyr
Thistlex contains clopyralid and triclopyr
Dow AgroSciences Limited, CPC2, Capital Park, Fulbourn, Cambridge, CB21 5XE. Tel: +44 (0) 1462 457272.
Technical Hotline: 0800 689 8899 email: UKHotline@dow.com | uk.dowagro.com