Research Note:Predicting Leucaena leucocephala biomass from simple morphometries

Abstract

A non-destructive method is required for estimating the forage yield of small stands of Leucaena leucocephala. Non-linear regression was used to investigate the relationship between the height of leucaena trees and wood and edible dry matter(edm)yield. and the relation between the diameter (at the point of browsing) of browsed leucaena twigs (DPB) and twig mass. Exponential regression (y = a + brx) of the logged biomass data provided the most accurate and precise description of the tree height-Biomass and DPB-biomass relationships. More than 75% of the variation in wood and total tree yield was accounted for by the regressions on tree height, at an accuracy of within 8%of the true mean. The regression for edm on height was poor (r² = 0.57) and was not improved substantially by including the number of basal stems as a predictor. The amount of leaf and stem material removed by browsers can be precisely (r² >0.90) and accurately (within 11% of the mean) predicted from DPB, thus providing a simple means of estimating browse offtake from leucaena trees.

Keywords: Browse, firewood, regression, tree height, twig diameter.

African Journal of Range & Forage Science 16(1&2): 118–121