Early spring utilization of alfalfa pasture

Patricio Soto O.1 y Ernesto Jahn B.

Date of first cutting and its effect on production and quality of an alfalfa pasture in the fourth and fifth year after seeding was evaluated. Six Cutting dates spaced every two weeks starting September 10 until November 21 were used. Total DM accumulation increased from September until end of November. Total DM production and pure alfalfa for each season was higher (P < 0.05) forthe last cutting date, as compared to first cutting at an earlier date. Ryegrass accumulation increases only until and of October. Total DM production until November 21 during the forth season was similar (P > 0.05) for treatments with one cut or with two cuts, but DM production of pure alfalfa was higher (P < 0.05) for a single cut. During the fifth season alfalfa cut initially October 10 which at November 23 had two cuts produced more DM than a single cut at the latter date. Pure alfalfa production until November 23 was higher for two cuttings as compared to one cut only. Crude protein and ME of alfalfa decreases, as an average for both seasons, at arate of 0.17% and 0.0055 Mcal per day, respectively, from the early vegetative stage until initial flowering. Production per ha for crude protein and metabolizable energy is maximized when the first utilization of alfalfa is done at the beginning of October.

Keywords: alfalfa, quality, early utilization.
1 Centro Regional de Investigación Quilamapu (INIA), Casilla 426, Chillán, Chile.