Entries are submitted by alfalfa seed companies and evaluated under field conditions. Although some modification of procedures has occurred since the beginning of the testing program, the following procedures are currently being employed. Red clover plants become infected from mycelium growing from the colonized grain and sclerotia are produced on stems and crowns of infected plants. During the spring and summer, sclerotia fall to the soil surface and gradually become buried in the upper 1 cm of soil. Alfalfa entries are seeded in late August or early September using no-till methods.
Irrigation is supplied as necessary to insure stand establishment and sclerotial germination.
Typically, apothecia emerge in October or November and release ascospores which infect alfalfa plants. The primary infection period usually continues until mid-December. Unsprayed Armor serves as a susceptible check cultivar. Beginning in late May, plots are harvested 4 times at approximately 35-day intervals, and dry matter yields are determined for each entry. In October, plots are undercut and industry representatives are invited to select plants for breeding programs.