AG NEWS
AG NEWS

Alfalfa Needs Attention, Too

  • Apr 07, 2016
close up on alfalfa
With most farmers zeroed in on planting corn and soybeans at this time of year, it’s easy to overlook another valuable crop that’s emerging for the season ?? alfalfa. While getting row crops off to a good start is essential, it’s also vital to keep an eye on alfalfa growth.

As I drove past a greening alfalfa field in southern Illinois last week, I stopped to check the new growth and found three to four alfalfa weevil larvae per stem. This early season pest, which favors new tissue in emerging alfalfa crowns, can quickly devastate the first crop and weaken the stand if left uncontrolled.

Due to the potential for heavy destruction, prompt treatment with an effective insecticide is recommended when these early pests are detected. A few tips for protecting your alfalfa crop include:
  1. Watch alfalfa fields carefully for dormancy break. As soon as green tissue emerges, start scouting fields.
  2. Check new growth across the field. As you shake alfalfa stems, flick larvae onto something with a white-colored background to determine the pressure level. Larvae are beige-colored initially, turning light green with a dark head.
  3. Determine a treatment plan. If insecticide preharvest intervals allow, spray immediately, even if you detect only a few larvae per stem, to protect the first cutting and ongoing stand health. If alfalfa is closer to harvest, cutting the crop may be the preferred control method.
  4. Choose an effective product. WinField offers several effective synthetic pyrethroid insecticides for control of alfalfa weevil larvae, including Grizzly® Too, Grizzly® Z and Arctic® 3.2EC insecticides. Consult product labels for PHIs and application rates.
  5. Check plant nutrition levels. While you’re checking for alfalfa weevil larvae, collect alfalfa stems to determine the crop’s nutrient levels. After sending stems in for NutriSolutions® Tissue Analysis, you’ll receive a plant health report and recommendations for any plant nutrient applications that may be needed to help address any deficiencies that may be keeping alfalfa from reaching its full yield potential.
Ask your local WinField retailer for more information.