Advice on transplant weed risk
THRIVING grass weeds could be transplanted rather than killed by spring cultivations, following good growing conditions through the mild winter. That could pose a particular problem when preparing sugar beet seed-beds, warns herbicide supplier Monsanto.
To combat the problem growers could use Roundup Biactive (glyphosate) after drilling, but pre-emergence, mixed with a selective residual such as chloridazon (Pyramin D F) or lenacil (Venzar), suggests Monsantos Jonathan Tann.
"An application at 1.5 litres/ha tank mixed with the residual component will take out the first flush of volunteers and annuals."
Although it may be too early to take decisions on herbicides, Mike May of IACR Brooms Barn agrees minimal cultivations will not kill big grass weeds with two plus leaves. Much will depend upon cultivation conditions in the next few weeks, he notes.
Monsantos new advice is in addition to traditional recommendations for use before or after cultivations.