Effects of Nitrogen Fertilization and Frequency of Cutting on the Yield and Composition of Pangola Grass in Puerto Rico

Abstract

The effects of nitrogen rates ranging from 0 to 1,600 pounds of N per acre yearly and of 30-, 45-, and 60-day harvest intervals on the yield and composition of Pangola grass were determined for 2 consecutive years. Yields increased sharply with nitrogen fertilization up to the 400-pound level, while protein content increased up to the 1,600-pound level. About two-thirds of the fertilizer nitrogen was recovered in the forage when 400 pounds or less were applied per acre yearly. Efficiency of utilization, in terms of dry matter produced per pound of nitrogen, decreased with increasing rates. Yields and lignin content of the forage increased while the protein content decreased with length of harvest interval. A 45-day harvest interval during seasons of flush growth, and a 60-day interval during the season of slow growth, combined with 400 pounds of nitrogen per acre yearly seems to be the optimum combination. Yields varied widely with season of the year.