DORMANT SPRAY FOR ALFALFA WEEDS

reproduced form "Hay and Forage Minutes" by Bruce Anderson, Nebraska Forage Specialist

In just a few weeks, warmer spring weather will green up your alfalfa. Before that happens, though, maybe you should do a little weed control. More in a moment.

Weeds like pennycress, downy brome, mustards, cheatgrass, and shepherd's purse are common in first cut alfalfa. They lower yields, reduce quality, lessen palatability, and slow hay drydown. If you walk over your fields during the next few weeks when snow is gone you should be able to see their small, green, over-wintering growth.

Once alfalfa starts growing, you can't control these weeds very well. However, if you treat your alfalfa as soon as possible during this winter’s next spring-like weather, you can have cleaner, healthier alfalfa at first cutting.

Several herbicides can help control winter annual grasses and weeds in alfalfa. They include Sencor, Velpar, Sinbar, Pursuit, Raptor, and Karmex. Also Roundup and Gramoxone. They all control mustard and pennycress but Karmex and Pursuit do not control downy brome very well.

To be most successful, though, you must apply most of these herbicides before alfalfa shoots green-up this spring to avoid much injury to your alfalfa. During mild winter weather would be a great time. If you wait and alfalfa shoots are green when you spray, your alfalfa growth might be set back a couple weeks. If it does get late, use either Pursuit or Raptor because they tend to cause less injury to your alfalfa.

Timing is crucial when controlling winter annual weeds in alfalfa. Get ready now, in the next few weeks before alfalfa greens up, to take advantage of nice weather when you get it.

This is Bruce Anderson, Extension Forage Specialist at the University of Nebraska. Talk to you again soon.