Fast growing maize crops need urgent weed control

Fast growing maize crops need urgent weed control
26 May 2017

Maize growers need to watch out for a rapid flush of weeds in newly sown crops following the recent turn in weather conditions across much of the country. So says Grainseed’s Neil Groom.

“The dry seedbeds common on many farms have kept the fields largely free from weeds, to date. But this will quickly alter after the recent rains,” he warns.

“Mid-May rain and rising temperatures will see maize crops and competitive weeds emerge rapidly now and this could be a problem if left unchecked. So it’s important to get your agronomist to walk your crops so a sound post-emergence herbicide strategy can be adopted and actives applied at the optimum time.”

First six weeks after emergence

Work by the Maize Growers’ Association has shown that the first six weeks after emergence is one of the most important stages of the crop’s development and keeping it weed free has a significant impact on final yields.

“Weeds need to be sprayed at cotyledon or first true-leaf stage,” explains Mr Groom. “When it’s warm, they can grow rapidly and by the time they reach the top of your boots, it’s too late. They need to be controlled when they are small.”

Re-evaluating winter forage stocks

With low yields of first-cut silage and a lack of rain during the spring, he adds that many growers are also re-evaluating their winter forage stocks and putting in extra maize fields.

“If you’re drilling in the second half of May, then choose a variety that is two maturity classes earlier than you would normally select. For example, use a maturity class 8 if you normally drill maturity class 6 varieties, and a 10 if you drill an 8. That will help to ensure that your crop finishes at the right time and produce high levels of starch and energy.”