Título en español.

An experiment to determine the effects of applying the total yearly nitrogen fertilizer to Pangola grass pasture in a heavy soil in three and in four portions was carried out. A mixture of Para grass and tropical kudzu with no nitrogen applications was used as check. Growing dairy heifers were used to measure differences, and the put-and-take system was followed, so that all the roughage was consumed from the plots. Equal amounts of phosphorus (P2O5) and potash (K2O) were applied annually to all the pastures. No statistical differences were found between treatments, indicating that it is probably not necessary to split the total of nitrogen fertilizer into more than three portions in a heavy soil like the Fajardo clay in which the experiment was established. Not taking other management factors into consideration the mixtures of Para grass and kudzu performed as well as Pangola grass.