BASAL AREA GROWTH OF EVEN-AGED <em>AZADIRACHTA</em> <em>INDICA</em> STANDS IN GUJARAT STATE, INDIA
Keywords:Neem, stand variables, basal area model, path invariant difference form equations, thinning
Azadirachta indica (neem) is one of the most important multipurpose tree species for not only the rural but also the urban people of lndia. The tree is found in tropical dry areas up to an altitude of 1200 m and it can thrive on a wide variety of soil and climatic conditions, Almost all parts of the tree have
one or more uses. Based on a comprehensive data set, this paper compares seven different stand level models for predicting basal area growth of even-aged stands of neem, located in Gujarat State, India. The models tested in this paper belong to the path invariant algebraic difference form of a non-linear model. The models can be used to predict basal area growth as a function ofstand lariables such as initial basal area, age or dominant height and stem number h-1 and are crucial for evaluating different silvicultural treatment options. The performance of the models for basal area was evaluated using different quantitative criteria. The Schumacher and Souter models showed the best performance. Aworked example of the effect of low and high thinning on basal area development is also given as appendix.