Broad-leaved weed flush on new grass leys

Check silage leys post-cut for regrowth

Encourage farmers to cover up when using pesticides

This edition's FAQs:

• Does Grazon 90 control buttercups?

• Update on grassland approvals

• Where can I find updated recommendations for Dow Shield 400 on sugar beet?

Good growing conditions this spring will result in large chickweed and other broad-leaved weeds in new leys. Quick to colonise any bare patches in gappy swards, chickweed  can soon outcompete perennial ryegrass for moisture, space and nutrients.

Product choice on new leys is increasingly restricted, but both Pastor* and Doxstar* still have recommendations for use this spring. A new ley is considered to be grassland less than 12 months old. Both products are safe to new leys from the 3-leaf stage.  Herbicides such as Doxstar and Pastor give good control against chickweed and will not harm the grass even when it is very young.

Doxstar has recommendations for control of common chickweed and seedling docks from the 2 leaf stage up to 50mm across at 1.5 L/ha in 200 litres of water.

Where a wider spectrum of weeds is present Pastor should be used at 2.0 L/ha in 200 litres of water from 2-leaf stage of broad-leaved weed. Label weeds include:

Key: etl = established true leaves

Where there is a large reservoir of seedling docks in the soil, a further application in the following year may be required.

In addition to the above, although we do not have specific recommendations, there are a number of non-label weeds which Pastor has strong activity on. These include:

Key: etl = established true leaves

A common situation is where large perennial weeds have survived the establishment of the ley and are competing with the crop. Control of these weeds is unlikely to be sufficient with the rates permitted on new leys and longer term measures in addition to the above, must be considered once the grass is established after 12 months. 

Both Doxstar and Pastor are rain fast within 2 hours if applied to a dry leaf.

Learn more about Doxstar

Learn more about Pastor 

The period between first and second cut is an ideal time for tackling docks, when they are actively re-growing. This means they will all be at the same stage of growth when sprayed – giving uniform results across the treated area.

The dry conditions heightens need to ensure any herbicides used do not check grass growth. Dow AgroSciences’ grassland herbicides based on triclopyr present a very safe approach - this was confirmed in IGER trials which demonstrated that there was no reduction in yield from spraying grass with this type of product.

For best results on docks spray Doxstar at 3L/ha in 300 litres of water/ha, when the docks are at the rosette stage and up to 25cm high or across.

Ideally allow two to three week’s re-growth after first cut so that the docks have big enough leaves to take the spray fully on board.

Advise farmers to wait at least four weeks before second cut, so that the weeds have a chance to transport the spray right down to the deepest roots for the most effective, long-term kill.

Pesticides are rigorously tested and safe as long as the requirements on the label are followed correctly.

All pesticides registered and sold for professional use by farmers have been thoroughly tested for any potential effects on human health.

In this country the trials and modelling data are also closely scrutinised by the Chemical Regulations Directorate (CRD) before they are allowed to be sold. Any herbicide, insecticide or fungicide registered here is safe - but with the incredibly important proviso that it is used under the conditions stated on the label.

Much of this is common sense – but it is still really important to check with farmers that they read the labels each time they purchase product and have access and use the necessary protective clothing. Even those that have used a pesticide for years and especially infrequent users such as livestock farmers spraying herbicides on grassland should be reminded of this as formulations and regulations do change.

The level of protective clothing needed, (known in the trade as personal protective equipment or PPE), reflects the registration conditions of the product. If the label states that gloves should be worn, then it says so for a good reason based on the scientific evidence.

One-off spills on the skin are unlikely to have any long-term effects, as long as the label recommendation of washing with water immediately is followed. But what is certain is that wearing the right PPE will virtually eliminate any risk.

Different operations with the same product may require differing levels of personal protection. For example, you may be required to wear an apron and face shield when handling the concentrate.   When applying pesticides via a knapsack the potential for exposure is higher and so more care must be taken in ensuring the use of appropriate PPE such as coveralls, gloves, rubber boots and even face shields.

Aftercare of clothing used when handling sprays is also important and often neglected.  Clothing worn for mixing and loading and during application should be laundered regularly to prevent build up of material. They should also be laundered separately from other clothing to prevent possible contamination.  Coveralls (or any contaminated clothing) should be washed immediately after a spill to prevent material soaking through and contaminating the skin, or transferring to other people. Gloves should be rinsed following contamination on the outside of the gloves and if it is suspected a spill has gone inside the gloves they should be disposed of and new gloves worn. Wearing contaminated gloves may lead to prolonged exposure. 

Does Grazon 90 control buttercups?

Grazon* 90 is mainly used in a knapsack and offers excellent control of docks, thistles and nettles and is especially used in paddocks and for weed control around the farm. In paddocks, buttercups can also be a problem and can be a concern as they contain glycoside ranunculin from which the irritant substance protoanemonin is formed. Many grazing animals, not just horses, are susceptible to this and when fresh buttercups are eaten, it can cause excessive flow of saliva, mouth-soreness and abdominal pain.

Grazon 90 offers some control of buttercups when used before flower-bud visible but control will not be complete.

Update on grassland approvals

What is the approval situation for Pastor, Doxstar, Grazon and Thistlex as of 1st April 2012?

Pastor MAPP no 11168 (same product & MAPP number with a label change only)
This product has now received approval through to 30th April 2018.
We have pre-produced 2012 seasons’ requirements with the existing label and the phase out requirement is as follows:
• The sale and distribution of existing stocks will end on 31 August 2012
• The disposal, storage and use of existing stocks will end on 31 August 2013

Doxstar MAPP no 11063 (our current Doxstar offer):
This product is now under revocation. Like Pastor we have pre-produced this season’s requirements with the existing label. The phase out requirements is as follows:
• The sale and distribution of existing stocks will end on 30th September 2012
• The disposal, storage and use of existing stocks will end on 30th September 2013

Doxstar Pro MAPP no 15664  (our future Doxstar offer):
This is a new high load formulation. It contains 150 g ai triclopyr and 150 g ai fluroxypyr. It will be available in 2lt packs (1 hectare). We will formally introduce it to the market for 2013 but anticipate and will plan for a small demand this autumn in light of the withdrawal period above.

Grazon 90 MAPP no 13117:
The CRD’s target completion date for a decision on this application has changed. The CRD are now indicating this to be late May 2012.  If this comes about there is likely to be phase out periods for sales. Prior to any decision date, Grazon 90 MAPP no 13117 remains approved for use.

In time we hope to replace Grazon 90 with a newer formulation with the same active ingredient concentration.

Thistlex MAPP no 11533:
This product is approved until 31/12/2021 so no implication for sales this year.

Please contact your local Dow AgroSciences’ Hotline on 0800 689 8899 for latest update.


Where can I find updated recommendations for Dow Shield 400 on sugar beet?

Dow AgroSciences has launched a new double strength formulation of its clopyralid-based herbicide in new packaging to reduce sprayer downtime.

Learn more about use on sugar beet. 

Subscribing to Dow AgroSciences' Agronomy Update & Pestwatch gives eligibility for 1 Crop Protection BASIS Points annually. Please include course name "Agronomy Update & Pestwatch" and number "CP/19948/1112/g" on your training record. These details apply until 31st May 2012.

If you require any further information please contact our technical Hotline on 0800 689 8899 or your local Dow AgroSciences representative.

Dow AgroSciences supports the safety and efficacy of its products for tank mixes shown as Physically and Biologically Compatible, but does not warrant the efficacy of other tank mix partners.

Use plant protection products safely.  Always read the label and product information before use.
For further information including warning phrases please refer to the product label.

* Doxstar, Grazon, Pastor and Thistlex are trademarks of Dow AgroSciences LLC.
^# Dow Shield is a trademark of the Dow Chemical Company.
All other brand names are trademarks of other manufacturers for which proprietary rights may exist.

Doxstar contains triclopyr and fluroxypyr
Dow Shield 400 contains clopyralid
Grazon 90 contains clopyralid and triclopyr
Pastor contains triclopyr, fluroxypyr and clopyralid
Thistlex contains clopyralid and triclopyr

More info at www.dowagro.com/uk