Experimental stands of leguminous forests in the Manaus region

Abstract

The increase in natural forest exploitation of the Amazonia in the last few years has led to increasing concern, in the sense of finding techniques to regenerate the native species, as well as for ecological reasons. In areas near Manaus, 50 native species have been planted in small plots which today are already about 20 years old. Some legume species were included in these experiments. Thus, this paper refers to an evaluation of the actual growth of these legume trees, as well as to initial information about the presence of nodules in these stands. From the tested legumes, Cedrelinga catenaeformis presents a faster growth in height and diameter, under shade. In the clear openning Diplotropis sp. presents good growth and good stem and crown formation. Vouacapoua pallidior presents very reduced growth, under plain light, while the other species showed a total average height between 9 and 12 meters and DBH between 10 and 13 cm at the age of 17 years, which can be considered good. C. catenaeformis presents good stem form and good crown characteristics, while Dipteryx odorata and Pithecellobium racemosum present, in general, excess of branching. Only C. catenaeformis, Dalbergia nigra and V. pallidior show nodulation in these stands.