Weed Watch-2024: Herbicide resistance testing

Teagasc launched a ‘Weed Watch-2024’ campaign with the Irish Farmers Journal to encourage growers and industry to utilize the weed seed resistance testing service to test suspect populations of Blackgrass, Italian ryegrass, Wild oats, Bromes, Meadow grass, Poppy, Chickweed, Speedwell, Corn marigold.

This invaluable service from Oak Park is now free for a limited time, as a part of the DAFM-funded EVOLVE grass-weed research project.

Are your weeds herbicide resistant?

Have you un-controlled weeds in your crop at harvest? You may have herbicide resistance.

Avail of free herbicide resistance testing from Oak Park for grass or broad-leaved weeds in tillage crops.

Target fields:

• Where weed control is poor after herbicide use
• Where the same herbicide is used every year
• Particularly if blackgrass/ Italian ryegrass/ poppy is present

We will test your weed and let you know the best herbicide and integrated weed management strategies to control this weed.

For further information, contact your Advisor

Click here for more information on the Weed Watch-2024 campaign

Tests conducted on resistance-suspect samples submitted by growers and industry prior to the 2023 harvest indicated that:

• >75% of blackgrass and 88% of Italian ryegrass were resistant to ACCase (Axial, Falcon, Stratos, Centurion) and/or ALS (Pacifica, Broadway) herbicides.
• 71% of wild oats were ACCase-resistant
• Resistance to ALS herbicides was confirmed in some annual and rough-stalk meadow grass
• Resistance to ALS (Ally Max, Cameo Max, Pacifica, Broadway) herbicides was confirmed in poppy, chickweed, speedwell and corn marigold. Populations of poppy and chickweed also exhibited resistance to hormone (2,4-D) type herbicides.

Due to rising resistance, testing is becoming more crucial than ever to identify which herbicides will work and what other integrated strategies to use, according to Teagasc researcher Vijaya Bhaskar.

If you have large uncontrolled weeds at harvest or suspect resistance, follow the instructions on the linked flyer to collect seed samples that can be sent for testing. For accurate and quick test results, collect ripe seeds and ensure they are fully dry before storing them in a paper envelope.