Relationship Between Stand and Yield in Alfalfa Variety Comparisons

Stand counts 1 Yields S NEW varieties of alfalfa are released, critical informaA tion on their relative performance over a state or region is desirable within a relatively short time. To accomplish this most satisfactorily, tests are established in as many locations as can be handled efficiently, and careful measurements or observations of important characters are made. In Maryland, most farmers require an alfalfa variety which will persist and yield satisfactorily over three harvest-years or longer. Replicated variety trials have been established in recent years in various locations in the state from which yield samples have been taken to differentiate among varieties with respect to yield and persistance. In addition, observational notes were taken on other important characters. The number of such locations were limited because of the amounts of labor and time required. Preliminary observations suggested a strong relationship, especially in the third harvestyear, between yield and number of surviving plants per unit of area. The object of this study was to determine the closeness of such a relationship at several locations. If yield and stand counts varied together closely, varietal differences in yield and persistence could be estimated relatively by stand counts. Thus, in addition to data from trials established for actual yield comparisons, information on new alfalfa varieties o r advanced strains could be obtained from many more areas of the state in a relatively short time. If such auxiliary plantings were a part of farmers’ alfalfa fields, all operations of cutting and removing of hay could be done by the farmer. Previous workers have re orted on the relationship of stand