Growers shouldn’t be put off making Atlantis WG (mesosulfuron and iodosulfuron) applications, as grass weeds are still growing thanks to favourable daytime temperatures.
“Don’t take your foot off the gas,” warns Darren Adkins, commercial technical manager at Bayer CropScience. “The autumn has been kind in most areas of the UK, stimulating strong emergence and reasonable conditions for pre-em herbicides.
“Now the weather is providing more opportunities to gain the upper hand. Where ground is sufficiently dry for travel and daytime temperatures are high enough for grass-weed growth, take advantage and spray Atlantis WG and a residual herbicide partner to maximise control.
“Each missed opportunity is a day when black-grass grows, gets bigger, stronger and harder to control,” he says.
Mr Adkins reminds growers there is no guarantee conditions will be better in 2014.
“Spring can be very unpredictable. Last year, for example, the extended winter caused havoc and when the weather did come right, there was an incredible amount to do in a very short space of time; when the sprayer is in demand for PGRs and T0s, you don’t want Atlantis WG applications on the list too.”
Countrywide agronomist Simon Trenary agrees. “If you can get a tank-full on, do it,” he says. “Wait until 11-12 o’clock when the leaves are dry and apply Atlantis WG with nozzles that deliver a medium-fine spray.
“It’s important to allow time for the product to dry too so I’d recommend stopping at around 2pm. This should provide the two hours needed for Atlantis WG to become rainfast. It’s a short window but even taking out a field or two at a time makes a big difference come spring."
Mr Trenary notes crops are better able to withstand herbicides in autumn than in spring. “Applications now will protect the crop and give it a chance to recover. By the time conditions come right in spring, the crop will be putting on fresh new growth which is more vulnerable to crop effects.
“If you need another reason, applications now - going into cold conditions - are documented to be more effective than those coming out.” adds Mr Adkins.
But none of the arguments are as good as Mr Trenary’s final point. “Killing black-grass sooner preserves more yield potential in the crop. It’s a very clear and simple point to remember."