For uniform fields 20 to 30 acres in size, count about 20 randomly chosen, square-foot areas and average the results. In addition to the plant stand, Reese recommends reviewing winter weather conditions. However, if there is adequate snow cover, it may not be as severe. Winter injury can range from total plant kill to reduced growth rate due to plant weakening. To determine cold injury and stand condition in early spring, dig plants and assess crown and taproot conditions.
Healthy taproots are creamy, white and firm in texture.
If taproots are spongy or watery and beginning to turn tan or yellow, the stand is likely severely cold-injured and deteriorating. If this is the case, Reese recommends checking the field again in about a week to confirm the assessment. When reseeding is necessary, seedbed preparation and following proper management steps are key to producing a healthy alfalfa stand. Soil pH should measure between 6.8 and 7, phosphorous and potassium levels should be medium to high and the seed needs to be treated with a fungicide. Certain crop rotations also help maximize alfalfa production.