Skip to Main navigation Skip to Left navigation Skip to Main content Skip to Footer

University of Minnesota Extension

Extension > Local Extension Offices > Morrison > County Agriculture Educator > Articles > Fall Alfalfa Considerations

Fall Alfalfa Considerations

University of Minnesota Extension, Stearns County News
September 23, 2015         
Source:  Dan Martens, Extension Educator
University of Minnesota Extension
Stearns, Benton & Morrison Counties


Fall Alfalfa Considerations
By Dan Martens, University of Minnesota Extension

FOLEY, Minn. (09/23/2015) — There are several things alfalfa growers might be considering this fall – fall cutting, fall stand assessments, stand termination timing and practices related primarily to nitrogen credits for the next crop. As usual, factors that drive how we think about these things vary from farm to farm and field to field. I’ll note here a couple of references that might be useful.

FALL CUTTING. The general concept is to cut close to September 1 so there is opportunity for plants to grow back enough to restore root reserves used to initiate new growth. The next option is to cut after October 15 with the goal that regrowth will not reduce root reserves any more. In this case, we suggest leaving a 6-inch stubble and a foot-wide uncut strip every 20 feet, depending on what fits well with the cutting width. It actually might take 4 nights of low temperatures around 24 degrees to shift alfalfa into dormancy.

This is largely a need and risk management decision. A risk assessment worksheet can be found by doing a website search for “Minnesota Extension Alfalfa Management Guide” and check page 60. Questions are based on age of stand, variety winter-hardiness, soil pH, soil potassium level, soil moisture and drainage, previous cutting schedule, and leaving a taller stubble.

ALFALFA STAND ASSESSMENT. Farmers looked at winter injury last spring and kept some fields that looked marginal in the spring. Some of these fields looked better with each cutting during the summer with suitable moisture. Some of these fields might be old enough so farmers already made new seeding decisions in the spring with plans to terminate questionable fields in the fall. Farmers and crop consultants may be evaluating field this fall.

Stems counts might be useful, but also might be affected by soil moisture conditions following the last cutting. Plant counts per square foot can be helpful. Digging some plants to examine the internal condition of roots might be most useful, along with plant and stem counts. You can expect some to find some brown decay inside the root of plants that have been harvested for a year or two. A good reference can be found by doing a website search for “Wisconsin Extension Alfalfa Stand Assessment.” Is has color pictures of root cores related to a 1 to 5 score for root health and potential for next year. You’re also welcome to call me for a copy. This publication says, “Use stem counts to estimate current yield potential. Assess root and crown health to consider future yield and winter survival potential.

FALL ALFALFA TERMINATION. Timing and practices for fall termination of stands can affect nitrogen credits for the crop planted on the field next year – usually corn. Soil texture can be a factor. It address issues such as fall versus spring termination, using a herbicide or not, first and second year nitrogen credits. This article can be found readily by doing a website search for “Minnesota Extension Managing the Rotation from Alfalfa to Corn.” Again you’re welcome to call me for a copy 320-968-5077 if a local call to Foley or 1-800-964-4929.

NATIONAL FARM SAFETY WEEK. September 20-16, 2015. The theme this year is, “ Ag Safety is not just a slogan.” I take that to mean it is something we talk about with our family and farm workers. Ultimately it is what we do. We wear the safety glasses. We put on the SMV sign. We fix the lights and the brakes. We avoid carrying extra riders. We stop equipment before reaching in. We stay out of bins and wagons when augers and elevators are running. We pay attention to the needs of other traffic on the road, whether we are the car driver or the farm equipment operator.

Let’s be working and learning together toward a safe harvest season.


Daniel Martens
Extension Educator, Ag Production Systems
(320) 968-5077
  • © Regents of the University of Minnesota. All rights reserved.
  • The University of Minnesota is an equal opportunity educator and employer. Privacy