Across the country, winter wheat growers should be applying their post-emergence blackgrass treatments now while blackgrass and other grassweeds are small, says Dow AgroSciences.
"In recent weeks, winter wheat in the Eastern Counties has suffered drought stress, but weeds have continued to grow – albeit slowly," says Stuart Jackson, Dow AgroSciences technical expert on grassweed control. "Some farmers believe they need to delay treatment until there are further weed flushes. Others are delaying treatment due to concerns over crop safety in the dry conditions where emergence has often been patchy.
"Our Grassweed Emergence Monitoring service shows dormancy is broken and weeds have emerged despite dry soils. Once soil moisture begins to rise any remaining blackgrass will emerge quickly and the unseasonably high soil temperatures will promote rapid growth, requiring treatment at the 1-3 leaf stage. Extensive trials and commercial experience has shown that the pyroxsulam-based products – Broadway* Sunrise and GF-2070 – are especially safe to crops, even when stressed. Therefore, concern over crop safety is no reason to delay treatment."
Broadway Sunrise is ideal where further flushes of grass weeds may occur. While the contact acting pyroxsulam will control emerged grass and broad-leaved weeds, the pendimethalin content will provide residual activity against any grasses that emerge subsequently.
For growers trying out the new GF-2070, the flupyrsulfuron-methyl component will provide some residual activity, Dow AgroSciences recommend adding a top-up residual, such as Stomp Aqua.
"In the North and Western areas of the UK, there has been adequate rainfall to allow crops and weeds to grow away. In these areas, growers should also be looking to get post-emergence treatments on for best effect on the full range of grassweeds including ryegrasses, wild oats and bromes," says Mr Jackson.
