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Alfalfa (Medicago sativa L.) is commonly grown in rotation with other crops but land can be continuously cropped with alfalfa. The purpose of this study was to determine the stand establishment and production of alfalfa cultivars that differed in disease resistance in a continuous alfalfa cropping situation, with limited supplemental irrigation. Two alfalfa cultivar experiments were spring‐seeded in 1970 at the Nebraska Agric. Exp. Stn. Mead Field Lab. on a Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudoll) soil with no known prior alfalfa cropping. The area was plowed in late May 1975 after the first cutting and fallowed. Soybeans (Glycine max L. Merr.) were seeded in 1976 on subareas reserved for seeding alfalfa in 1977 and 1978, and in 1977 on the subarea reserved for seeding alfalfa in 1978. Two alfalfa experiments were spring‐seeded per year in 1976, 1977, and 1978, a foliar fungicide and a fungicide seed treatment experiment. Forage yields did not differ among foliar fungicide treatments or between ‘Arc’ and ‘Ranger’ in the year of seeding or in subsequent years. Anthracnose (caused by Colletotrichum trifolii Bain) and foliar diseases were at subeconomic levels. Stands in the year of seeding did not differ among fungicide seed treatments or between ‘Agate’ and ‘Dawson’. Anthracnose and phytophthora root rot (caused by Phytophthora megasperma Drechs) were factors in stand decline and yield reduction of susceptible cultivars after the year of seeding. Stands in the year of seeding were excellent on the same land area where alfalfa was seeded in 1970 with no known previous alfalfa cropping, after plowing the 5‐year‐old stand of alfalfa in 1975 and seeding in 1976, and after 1 or 2 years of soybeans and seeding alfalfa in 1977 and 1978, respectively. Average forage yields of the experiments seeded in 1970 were 26% higher in the year of seeding, and 40 and 35% higher in the 1st and 2nd year after seeding, respectively, than in the experiments seeded in 1976 to 1978.

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New sources of high quality protein are needed for human consumption. Alfalfa (Medicago sativa L.) is well known for its high yield of protein. Knowledge of genetic variation for protein concentrate yield among cultivars is needed. The alfalfa cultivars ‘Dawson’, ‘Kanza’, ‘Team’, and ‘Weevlchek’ were planted in field plots at the Mead Field Laboratory, Lead, Nebr., in 1972. Forage of the cultivars was harvested and sampled as three growth stages, bud, one‐tenth bloom, and full bloom, in the first and second cuttings of 1973. Forage samples were used for chemical analyses of fresh forage, pressing juice in the laboratory, protein extraction, and subsequent chemical analyses. The purposes of the study were to determine the yield of an alfalfa protein concentrate (without chloroplasts) (APC) from four cultivars at three growth stages, the forage yield and quality of fresh forage, and to determine the recovery and nutrient levels in the residue of processed forage. The cultivars did not differ in dry matter,protein,and carotene levels of fresh forage at any growth stage in either the first or second cutting. The percentage of protein in APC's did not differ among cultivars at any growth stage in either cutting and averaged 76%. Forage and APC yields differed among Cultivars. The lowest forage and APC yields were obtained from Kanza. About 1% of the fresh weight of alfalfa was recovered as APC. APC yield averaged about 200 kg/ha over cultivars and cuttings. APC recovery percentages differed among cultivars and the lowest recovery was from Kanza. Protein recovery decreased as physiologic mauturity increased. At one‐tenth bloom, average protein level of fresh forage was 18.6% compared with 16.4% protein in the residue after pressing (juice extraction), a 12% reduction due to processing. Average carotene level of fresh forage was 190 mg/kg, and carotene level of the residue was 145 mg/kg at one‐tcnth bloom, a 24% reduction. The yield of an alfalfa protein concentrate that contained 76% protein, potentially suitable for human consumption, vaned among cultivars as shown in this preliminary study.

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