If fall seeding, seed as early as possible to allow plants to develop larger, more resistant crowns. Deep plowing can reduce spore levels by burying sclerotia. However, plowing does not assure a disease-free stand since spores may arrive from neighboring fields. Resistant varieties are not available. Rot of seeds and damping off of seedlings before or after emergence.
Crop rotation does little to reduce their populations.
Generally they do not limit stands of alfalfa seedlings, but can do so during periods of high soil moisture. Select well-drained fields. Prepare a fine but firm seedbed if seeding using conventional tillage. Use high-quality seed of adapted varieties. Plant varieties with resistance to Aphanomyces where this disease occurs.