ABSTRACT
The present work was established with the objective to determine functions to estimate the production of tannin of Acacia-negra, Acacia mearnsii De Wild in kilograms per tree and hectare. Thus dendrometrical information was collected in 32 experimental plots, stratified by the age of 3.5 up to 8.5 years, on good and poor sites with different spacings. Tannin content was measured on the basis of 64 trees, 32 trees with medium diameter and 32 trees with dominant height. The results obtained allow the following conclusions: a) The production of tannin (PTA) in kilograms per tree can be estimated in function of diameter (d) in cm, height (h) and medium distance between the trees in meters after one of the following equations: ln PTA = - 6.0141145 + 2.43202867. ln d + 1.0413106. ln EM; ln PTA = - 5.853512 + 1.53029074. ln d + 0.38185298. ln (d²h) b) The production of tannin in kilograms per hectar (PT) can be expressed in dependance of basal area (G) in m2/ha and dominant height (ho) in meters, and estimated with the equation: ln PT = 3.5222278 + 1.1417977. ln G + 0.2031873. ln ho
Key words:
yield; tannin; Acacia mearnsii.; acácia-negra.