Alfalfa Management Tactics
Apr 02, 2021
5 Preseason Tips for a Robust Alfalfa Crop
“Herbicide carryover is like the dog that doesn’t bite… Until the dog bites.”
DO:
- Select the right alfalfa varieties for your acres, such as HVX MegaTron, RR AphaTron 2XT, LegenDairy AA, and Rebound AA, keeping disease resistance and yield potential top of mind.
- Maintain optimal soil fertility for yield and quality.
- Pay attention to previous crop chemistry.
- Understand the importance of seed treatments.
- Develop a season-long management plan.
“Herbicide carryover is like the dog that doesn’t bite… Until the dog bites.”
- Herbicide carryover from new residual herbicides (Groups 4, 27, and 14) used on previous crops can result in poor alfalfa establishment, weak stands, stunted growth, or stand failure.
- Forage Specialist and National Alfalfa Agronomist, Randy Welch, offers his insights to the ongoing issue in this article.
- This video from Forage Specialist, Jeff Jackson, provides a quick guide of avoiding herbicide carryover in alfalfa.
- Rotation restrictions for commonly used herbicides can be found here.
DO:
- Review previous herbicide applications and the rotational crop considerations.
- Review all the active ingredients in the premixes, not just brand name.
- Read and follow the label directions including footnotes.
- Plan ahead and develop a herbicide plan that includes alfalfa production.
- Always plan for the unexpected if winter damage occurs.
- Rely on increased rainfall to decrease herbicide carryover.
- Expect a reduced application rate to decrease herbicide residual time.
- Apply herbicides later than specified on the label, as this may increase residual risks.
- Assume tillage will eliminate herbicide residual activity.
Soil Fertility for New Alfalfa Seedings
Soil test recommendations before seeding alfalfa:
- pH: 6.8-7.2
- Phosphorus: 15-20 ppm
- Potassium: 150-200 ppm
- Boron: 1 ppm
- Sulfur: 20-25 pounds