Trend of Carbohydrate Reserves in Alfalfa, Smooth Bromegrass, and Timothy Grown Under Various Cutting Schedules 1

LFALFA, one of the most important forages grown in A the northern United States, is sown usually with a grass, principally bromegrass or timothy. Therefore, when managing an alfalfa-grass mixture, one must consider the growth characteristics of both the legume and the grass in order to maintain a desired proportion of each species in the mixture. A close relationship of herbage production and persistence with the level of organic food reserves has been demonstrated in alfalfa by Graber et al. ( I ) , Grandfield (2), Graumann et al. (3), Nielsen and Lysgaard ( 7 ) , Smith ( 8 ) , and others. Studies of the trend of food reserves in the storage organs of bromegrass and timothy are few. Tee13 has indicated that available fructose in the shoot bases of bromegrass was at a low level when internode elongation began in the spring, increased during internode elongation until heading, decreased during flowering, and then increased to the ripe seed stage. Kust4 found that carbohydrate reserves in bromegrass rose somewhat in the early spring, decreased until emergence of the heads, and then increased to anthesis. Carbohydrates usually decreased following cutting. Harper and Phillips (4) and Kust4 found that carbohydrate reserves in timothy decreased in the spring and then increased to a peak near full bloom. Harper and Phillips ( 4 ) also found that the carbohydrate reserves in timothy decreased very little following cutting at near full bloom, but Kust found some decrease. Troughton ( 9 ) and May