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Post Rock District

Beloit Office
(785) 738-3597

Lincoln Office
(785) 524-4432

Mankato Office
(785) 378-3174

Osborne Office
(785) 346-2521

Smith Center Office
(785) 282-6823

Weed Control

Weed Management in Alfalfa

Here are some guideline recommendations for managing weeds in Alfalfa from Dr. Sarah Lancaster, K-State Research and Extension Weed Specialist:

-In Roundup Ready alfalfa, one could consider glyphosate, if the pigweed population is still susceptible.

Another alternative is Raptor, if the pigweed population is still susceptible to ALS-inhibiting herbicides.

-Some of the better options for established alfalfa would be to use dormant applications of a product that contains diuron (such as Karmex or AlfalfaMax). Metribuzin or Sharpen could also be used as a dormant application. Another alternative for established stands would be Paraquat (Gramoxone) applied immediately after cutting.

-In a first-year stand, bromoxynil (Moxy, etc.) or 2,4-DB (Butyrac 200, etc.) can be effective. The key is to apply herbicides to small pigweeds. In addition, application is limited by alfalfa growth stage and weather for these herbicides.