Pre-Emergence Herbicides Crucial for Winter Barley and Wheat Weed Control

Pre-emergence herbicides are playing an increasingly important role in winter barley and wheat weed control, according to Teagasc. By reducing early competition from grass weeds, these herbicides provide a crucial opportunity for farmers to establish effective control.

The growing use of pre-emergence herbicides among tillage farmers reflects a greater awareness of the threat posed by grass weeds and herbicide resistance. Pre-emergence herbicides are particularly important in resistance management, as they reduce reliance on post-emergence chemistry where most of the resistance issues arise.

Winter barley is particularly vulnerable to grass weed control, with limited options available for controlling established weeds. Effective pre-emergence treatment is essential, especially in fields with a history of grass weeds, early-sown crops, or land that may be difficult to travel to later in the autumn.

When applying pre-emergence herbicides, growers should aim to do so within 24-48 hours of sowing and ensure that the seedbed is fine and firm with adequate soil moisture. Residual herbicides work best under these conditions, and a minimum of 2-3cm soil cover is required.

Pre-emergence herbicide options include prosulfocarb, such as Defy, and pendimethalin, such as Stomp. Combination products like Tower, Mateno Duo, and Flight are also available, but growers should check their pesticide stores for other suitable options, including flufenacet-containing products.

The deadline for applying pre-emergence herbicides is December 10, after which product use becomes illegal.