EFFECT OF LIMING AN ULTISOL FOR THE ESTABLISHMENT OF A TROPICAL HARDWOOD IN SOUTHERN NIGERIA

Abstract

A soil culture experiment was set up in the greenhouse to evaluate the response of Terminalia superba Engl. and Diels (afara) to different pH levels through timing for plantation establishment. An acidic soil (ultisol) collected from Sapoba Forest Reserve in southwestern Nigeria was used.

The results indicated that optimum growth and total dry matter yields were obtained when the soil pH was between 5.9 and 6.1. Depressed growth and yields occurred at low and high pH. The effective cation exchange capacity (CEC) and exchangeable Ca in the soil increased significantly (P=0.05) with increasing lime addition while Mg, K, Na, Mn, and exchangeable Al+H decreased. Highest nutrient concentrations in the leaves of the plants occurred between pH of 5.7 and 6.1 for P, 6.3 and 6.5 for Ca, 5.9 and 6.5 for K and between 6.0 and 6.5 for Mg.