Grass weed control and herbicide tolerance in cereals.

Field trials were undertaken over three years to determine herbicide options for grass weed control in cereal crops (wheat and barley). The susceptibility of phalaris, perennial ryegrass, Italian ryegrass, prairie grass and soft brome to a range of herbicides were evaluated at fixed rates and with a logarithmic sprayer. Wheat and barley damage and grain yield were also assessed and in general good tolerance was found in the 11 cultivars evaluated. The trials identified a number of control options for grass weeds in wheat and barley, in particular pre-emergence mixtures of cyanazine + terbuthylazine; chlorsulfuron + terbuthylazine; or metribuzin alone. Brome species were the most difficult to control and further research is required.