Strong blackgrass growth

Strong black-grass growth despite low soil temperatures

Despite frosts and soil temperatures rarely reaching 6°C continued monitoring at Bayer CropScience’s trial sites reveals black-grass is active and is showing visible growth.

"During the last three weeks black-grass has put on one to two leaves and one to two tillers, which means that herbicide applications are fast becoming a pressing task,” observes Dr Gordon Anderson-Taylor, herbicides development manager at Bayer CropScience.

Close observation of the trial plots confirms yet again that relying on any one growth indicator such as soil temperature can be misleading. Getting out there and physically assessing fields is the only reliable method of gauging black-grass activity.

“Black-grass which received an effective pre-em treatment is still notably behind that which didn’t. Pre-em survivors are around the two to three leaf stage for October drilled crops, giving growers the opportunity to get good control.

“But growers cannot be complacent,” warns Dr Anderson-Taylor. “Black-grass is demonstrating its ability to grow even in unfavourable conditions and as we move into spring these small plants will only get stronger and bigger.”

“Untreated September drilled crops are now an urgent priority as these fields may have black-grass that is well-tillered and highly likely to be a challenge to control. Even those that received a pre-em will be close behind and demand growers’ attention.

“Black-grass will continue to progress rapidly through the growth stages in the next few weeks. The majority of growers can still get good control but they need to spray as soon as conditions are suitable. Fields must be prioritised – those without pre-em treatments and those at the latest growth stage need to come first.”