The average winter wheat herbicide spend recorded in the latest Monsanto study of almost 400 farms with over 150,000 ha of arable cropping is currently £89/ha, with a third spending over £100/ha and more than one in every 10 over £125/ha (Figure 1).
Unsurprisingly perhaps, herbicide spend is closely related both to the proportion of winter cereals area on which black-grass is a problem and the extent and severity of black-grass resistance.
Growers with the most widespread black-grass problems are spending an average of £106/ha compared to £63/ha for those with few, if any, problems (Figure 2). In the same way, growers experiencing serious or very serious resistance problems are spending around £101/ha on herbicides against £72/ha for those with slight or no resistance problems.
In Black-grass control, in particular, the study shows that growers establishing their winter cereals with some form of reduced tillage are relying to a much greater extent on chemistry than those with plough-based systems. This is especially the case with pre-planting, autumn pre-emergence and autumn post-emergence treatment.
On average, they are employing 2.7 sprays at a cost of £91/ha compared to 1.9 and £74/ha for those using the plough. Over four in every 10 growers relying on minimum tillage, indeed, is spending £100/ha or more on winter cereal herbicides. This compares with less than two in every 10 of those with plough-based establishment.