Methodologies in the evaluation of forage mass in tree legumes

Abstract

To choose the method of forage mass estimation (FM), consider the plant species, required accuracy and available technology. In this sense, the objective was to evaluate the methods of determination of direct FM and comparative visual performance with five and 10 patterns, in the trees Gliricidia (Gliricidia sepium Jacq.) and Sabiá (Mimosa caesalpiniifolia Benth.) At heights up to 1,5 m above the soil and whole plant (1.65 to 1.90 m for Gliricidia and from 3.63 to 5.03 m for Sabiá, with averages of 1.80 and 4.24 m, respectively), using the plant as a unit sample. The evaluations were performed every 28 days for one year, 2012 to 2013. The trees were cultivated in silvopastoral system with brachiaria, under continuous stocking of cattle with initial weight of ± 175 kg. The methods analyzed by regression in the collection cycles and annually and compared by the 5% F test. At the evaluated times it is possible to estimate the FM production by the indirect method, with no differences in the number of standards. The average annual FM of 118.547 kg in 2,250 plants of Gliricidia ha-1, slightly varying between heights. At Sabiá the annual average FM was 398.241 and 702.281 kg in 2,250 ha-1 plants, at heights of up to 1.5 m above the ground and whole plant, respectively. The use of the plant as a sample unit, allowed high determination coefficients above 0.800 in the annual analyzes, for the indirect method.