Survey: bromes the most common grass weed

A survey of 103 farms showed that brome grasses were the most common grass weed on these farms.

Vijaya Bhaskar outlined the findings at the Teagasc national tillage conference in Co Kilkenny last week.

The survey, which was carried out as part of Teagasc’s Enable Conservation Tillage project, was carried out on 62 plough-based farms and 41 non-inversion tillage farms.

Grass weed assessments were carried out on those farms in 2020 and again in 2021.

Fifty-three per cent of plough-based farms had bromes on farm, while 77% of non-inversion tillage farms had brome grasses on their farm. The full results can be seen in Table 1.

Wild oat numbers were similar across both systems and were high at 56% to 57%. Italian ryegrass levels were also similar on both systems at 12% to 13%.

Nineteen per cent of plough-based farms surveyed had blackgrass, while 10% of non-inversion tillage farms surveyed had blackgrass.

Vijaya commented that blackgrass infestation looks to be more to do with location than it is to do with establishment systems.

Blackgrass infestation looks to be more to do with location than it is to do with establishment systems.

Of the farmers with blackgrass, 38% of growers didn’t know they had blackgrass until it was identified by Teagasc.

Eighteen of the 103 farms had resistant grassweeds and Vijaya pointed out that multiple resistance in blackgrass is now a serious threat to crop production.

The Teagasc researcher encouraged all farmers to send grass or broad-leaved weeds to Teagasc for testing if you think you have a resistant weed.