Leaf properties, litter fall, and nutrient inputs of Terminalia ivorensis at different tree stand densities in a tropical timber - food crop multistrata system

Abstract

Tree litter fall was monitored for 2 years in two Terminalia ivorensis A. Chev. plantations in the humid tropics of southern Cameroon. The plantations were 6 and 17 years old when they were each thinned to two timber stand densities (TSD) and understorey food crops were introduced. Leaf litter was the predominant litter fraction in all treatments. Treatment means of specific leaf area for T. ivorensis ranged from 83.7 to 100.7 cm2·g-1. Litter-fall production, leaf area per tree, and leaf area index for T. ivorensis were all higher in year 2 than in year 1. There was near complete defoliation of the T. ivorensis stand by Epicerura sp. (Lepidoptera: Notodontidae) caterpillars in the month just before the start of litter-fall sampling. This is the first report of an Epicerura sp. from Cameroon. Terminalia ivorensis leaf litter production per tree, specific leaf area, and leaf litter nutrient concentrations showed few significant differences between TSD treatments. This lack of response suggests that T. ivorensis is a suitable species for growing at stand densities lower than is normal silvicultural practice in association with food crops.