Onion Pest Control

Seeking Your Input on New Research for Weed Control in Onion

We are initiating new research on cost-effective pest control for onion in New Mexico. Your input will ensure that this research produces results that are applicable to your farm.

Initially, our research focuses on weed control. We think weed control costs and potential environmental impacts can be reduced with the following two additions to onion herbicide programs:

1. SLN registration for delayed pre-emergence (after onion germination but before onion emergence) applications of pendimethalin .
   • Pendimethalin is a soil-applied, residual herbicide that terminates grass and broadleaf weeds as they emerge.
   • This herbicide has become an important component of weed control programs for onion.
   • Currently, New Mexico onion farmers can apply pendimethalin when dry bulb onions have 2 to 9 true leaves.
2. New recommendations for pyroxasulfone which enable this herbicide to supplement or replace post-emergence applications of pendimethalin.
   • Pyroxasulfone was first registered for dry bulb onion in 2019.
   • This soil-applied, residual herbicide can be applied when onions have 2 to 6 true leaves.
   • Pyroxasulfone provides preemergence control of grass and broadleaf weeds; emerged weeds will not be controlled.
   • Only one application of pyroxasulfone is permitted during the onion growing season.

Please take a few minutes to complete the 3-Minute Survey. We thank you in advance for your insights.

Contact Info

Brian Schutte
Department of Entomology, Plant Pathology and Weed Science
New Mexico State University
Phone: (575) 646-7082
Email: bschutte@nmsu.edu