Later window encourages Dow Shield 400 usage in game cover crops

Until last year Dow Shield 400 (clopyralid) had an EAMU for game cover crops, but it had a cut-off date of the end of May, which was far too early for any practical use.

Most game cover crops are drilled in April or May and so will be treated for weeds in May or June.

This contact herbicide now has an extended window to the end of July in the year of application, so its use will be a lot more practical for those who want to create a better game cover.

Game cover crops need managing, with weed control being an essential part of this management as is the case with all crops. Reducing weed pressure helps crop establishment.

Dow AgroSciences has responded to queries on their Hotline and have secured an extended timing application until the end of July for the Extension of Authorisation for Minor Uses (EAMU) for the use of the herbicide Dow Shield 400 in crops grown for game cover.


Several different crop species are established each year to provide shelter and food for game birds.

Dow AgroSciences have run a series of trials over two years to establish the safety of their advanced clopyralid formulation on a number of commercially available mixes and crop types used in game cover.

The screens demonstrate that at 0.25 l/ha of Dow Shield 400 there was no damage on red millet, white millet, sorghum, maize, mustard, quinoa, Gold of Pleasure or borage.

Buckwheat suffered minor but transient damage. However sunflowers, red clover and chicory were significantly damaged and should be avoided in any mix.

When the dose rate was raised to 0.5 l/ha, white millet, sorghum, maize, Gold of Pleasure and borage were again unaffected, but at this higher dose rate red millet, mustard, quinoa and buckwheat showed minor crop damage.

"Dow Shield 400 controls difficult perennial and annual weeds including creeping thistles, volunteer potatoes, corn marigold, groundsel, mayweeds and smooth sow-thistle.

"It should be applied at 4 to 5 leaves of the game cover mix.” says Peter Waite of Dow AgroSciences.


"The product has been reformulated and re-registered as a double strength formulation. The more concentrated formulation and advanced packaging with self-seal technology and no foil to dispose of has made it easy to handle, reducing point source contamination risk and makes spraying more streamlined," points out Peter.

"Dow Shield 400 has full label recommendations for 19 different crops, including swedes, turnips, mangels, bulb onions, broccoli/calabrese, cabbage, cauliflower, fodder beet, forage maize, linseed and Brussels sprouts as well as most cereals and rape and EAMUs, including asparagus, garlic, shallots, chard, spinach, spinach beet, Chinese cabbage, kale, collard, outdoor leafy herbs, outdoor leeks and salad onions.

"Adding together its label recommendations and EAMU’s, well over 50 crops can be treated with Dow Shield 400 and the list is always growing and evolving.

"Dow Shield is enjoying its 40th anniversary this year. So it has been helping UK farmers for four decades now," says Peter.