Evaluation of methods to estimate foliage density in the understorey of a tropical evergreen forest.

Foliage density and leaf area index are important vegetation structure variables. They can be measured by several methods but few have been tested in tropi cal forests which have high structural heterogeneity. In this study, foliage density estimates by two indirect methods, the point quadrat and photographic meth ods, were compared with those obtained by direct leaf counts in the understorey of a wet evergreen forest in southern India. The point quadrat method has a ten dency to overestimate, whereas the photographic method consistently and significantly underestimates foliage density. There was stratification within the understorey, with areas close to the ground having higher foliage densitie