Abstract

This experiment was carried out at the Alfredo Volio Mata Dairy Cattle Experimental Station in Costa Rica. A mulberry bush plantation was divided into three plots: with a distance of 60, 90 and 120 cm between rows and plants. All plots were uniformly pruned at 60 cm from the ground. During a 224-day period, these subplots were pruned consecutively every 56th, 84th and 112th day. The annual yield of dry matter of the whole mulberry bush (stems and leaves) was influenced (P = 0.01) by all the factors studied. The planting distance had a decreasing effect on the Yield of stems and leaves increased as the distance decreased. The cutting frequency had a marked influence (P = 0.01) on the production of biomass in the whole plant and its parts. A linear effect (P = 0.01) was observed on the stem yield, as well as the whole plant, when the cutting interval increased between the 56th and 112th days. Anegative effect (P <0.05) was observed in the leaf:stem ratio when the pruning interval was increased. The nitrogen dosage used in the experiment (0, 150, 300, 450 and 600 kg/ha) did not show a differential effect (P < 0.05) on the total biomass yield nor on the stem or leaf production. No significant effects were observed between the planting distance or the cutting frequency and the nitrogen dosage.