LAUSR

Abstract Seasonally dry tropical forests (SDTF) currently occupy only 10% of the original area of their natural distribution. In the Maranon river valley, north western of Peru, occurs one of the most important SDTF of the neotropics. It has an endemic woody flora that represent 32% of the species, being threatened by its increasing fragmentation, and the knowledge of the ecology, forestry and conservation of the tree species is scarce. In this context this work presents the result of evaluation of the wood anatomy with emphasis to growth ring analysis, dating trees and stem growth rate determination of four tree species: Anadenanthera colubrina (Vell.) Brenan, Cedrela kuelapensis T.D. Penn. & Daza, Cordia iguaguana Melch. Ex I.M. Johnst., and Esenbeckia cornuta Eng., the last three being endemic and threatened with extinction. Our results determined that Cedrela kuelapensis showed the highest radial growth of the stem in relation to the other congeners of the neotropical region. Lower stem growth was observed for E. cornuta trees, according to the pattern of other tropical species. The results also indicate that populations of C. iguaguana and Esenbeckia cornuta in the zone are mainly composed by young trees exhibiting strong anthropic pressure due to the quality of their timber and, in consequence, more efforts are needed in the management of these resources to guarantee their sustainability.