New innovation for broadleaf weeds in plantain

As use of the forage herb plantain continues to rise on farms all over New Zealand - sown as a pure sward, with clover, or in combination with ryegrass-based seed mixes - so too has risen the challenge of weed control.

No-one wants broadleaf weeds infesting newly-sown pasture mixes, even when the pasture contains something that not so long ago was itself considered a broadleaf weed.

Best practice recommendations for plantain emphasise the importance of eliminating broadleaf weeds if they become apparent in early establishment.

Up until recently, however, the number of herbicides registered in New Zealand for post-emergence broadleaf weed control in pure plantain, plantain and clover, and pastures containing plantain, has been limited.

Now a new choice is available. Dictate® 480 herbicide from Nufarm, which contains 480 grams/litre of bentazone as the active ingredient, has recently been approved for this use.

Nufarm Technical Specialist Paul Addison says this is a positive development for the increasing number of farmers keen to take advantage of plantain's potential environmental benefits and nutritional value in their systems.

Research in Canterbury and Waikato as part of the Forages for Reduced Nitrate Leaching programme found that the urine-N concentration of cows grazing plantain was 56% lower than those grazing perennial ryegrass/white clover pastures, and 33% lower for cows grazing 50/50 pasture-plantain.¹

Paul says Nufarm trials² done to support the application for the new claim have shown Dictate® 480 is softer on plantain than another herbicide registered for the same use, while still providing acceptable weed control.

"We compared plantain plant numbers and dry matter yield in two trials in new pasture sown with plantain. There were a number of different treatments including an untreated control; Dictate® 480 at 3 litres (L) per hectare (ha), and a combination herbicide (bentazone and flumetsulam) at 3L/ha."

Both plantain plant numbers and dry matter (DM) yield were highest for the Dictate® 480 treatment when the new pasture was assessed just prior to the first full grazing, four to five weeks after spraying.

The Dictate® 480 treatment had significantly more plants and higher DM yield than the bentazone and flumetsulam combination herbicide.

"Some plantain leaf burning will be evident after applying Dictate™ 480, but plant vigour is hardly affected and no plant mortalities occurred," Paul says.

A 14-day stock grazing withholding period applies after using Dictate® 480 on plantain, plantain and clover and pasture mixes containing plantain.

Timing is important, says Paul.

"For best results, apply when weeds are small, and plantain is at the two to four leaf stage. Add Contact™ Xcel surfactant to ensure good leaf coverage."

For more information on getting the best out of forage plantain this season, talk to your local TSR or visit your Farm Source store today.

Article supplied by Nufarm.

¹ (n.d.). Plantain. Dairy NZ. https://www.dairynz.co.nz/feed/crops/plantain.
² Nufarm trials NUNZ2053 and NUNZ2064 Dictate™ is a trademark of Nufarm Limited.