Older alfalfa stands may not be providing optimum value per acre for producers.
But there are a few easy ways to check stands to see if a producer is getting the most value from these alfalfa fields, according to an expert with Pioneer Hi-Bred International, Inc.
"Today's alfalfa growers and livestock producers can't afford not to get the maximum value per acre from their forage," says Carl Bannon, Pioneer technical information manager. "It is important to plant varieties that offer top yields and quality. And it is just as important to double-check established stands, especially if they are more than four years old. If these older stands aren't producing at optimum yield levels, it is better to rotate to corn or another crop."
According to Bannon, as stands get older they thin out, resulting in decreased yields and increased weeds. The weeds reduce the forage quality of the alfalfa and make drying to the correct harvest moisture more difficult.
It is relatively easy to check the health and population of older stands, Bannon says. Begin by counting the number of plants in one square foot, at several locations throughout a field. The alfalfa population in an established stand should average at least four plants per square foot.
A second method for evaluating alfalfa stands was developed by University of Wisconsin forage agronomists Dan Undersander and Dennis Cosgrove and involves counting alfalfa stems. This method allows a producer to wait until stems have grown six to 10 inches before checking the number of stems per square foot.
Stem counting offers a more accurate idea of stand health and yield potential. If there are more than 55 stems per square foot, maximum yield potential can be expected. Stem counts dropping below 40 stems per square foot can reduce yield by 25% or more. If stem counts fall below 40 per square foot, consider rotation. A producer also can check the health of the stand by digging up several plants and checking for crown and stem rots.
"It is important to know if your alfalfa varieties are producing yields that make a difference for your farming operation," Bannon says. "If they aren't, rotate to another crop, then re-seed with newer varieties the following year.
"We have a number of excellent Pioneer varieties from which to choose, including Pioneer brand variety 5454, which sets the standard for fast regrowth and recovery," Bannon says. "Also, new 54V54 offers top yield potential and excellent disease resistance, and 53Q60 exceeds the National Variety Review Board standard for high quality designation."
Once a producer has checked older stands and selected new varieties, Bannon suggests following proven management practices to ensure quality alfalfa production.
Prior to planting, make sure the soil pH measures between 6.5 and 7. Be sure to set good seed-to-soil contact by rolling or culti-packing prior to and after seeding alfalfa. After seeds have emerged, scout fields to determine if weed control is needed. In addition, scout for potato leafhoppers when plants are three to six inches tall.