INFLUENCE OF SPACING ON GROWTH AND YIELD OF <em>TECTONA</em> <em>GRANDIS</em> LINN. F. (TEAK) AND <em>TERMINALIA</em> <em>SUPERBA</em> ENGL. & DBELS (AFARA)

Abstract

The effects of spacing in relation to growth and wood production in 18-y-old Tectona grandis (teak) and 13-y-old Terminalia superba (afera) were investigated in trial plots established at Gambari Forest Reserve, southwestern Nigeria. The following spacing regimes were investigated in the Tectona grandis stand: 1.37 x 1.37 m, 1.98 x 1.98 m, 2.9 x 2.9 m and 3.96 x 3.96 m. For Terminalia superba, the spacing regimes* investigated were 1.8 X 1.8 m, 2.8 x 2.8 m, 4.2 x 4.2 * and 6.1 x 6.1 m. The results showed that in both species percentage survival, diameter at breast height (dbh) and specific gravity increased with increasing espacement white merchantable height, stem volume and basal area decreased with increasing espacement.

From the results of the present and previous studies, the planting espacement in the high forest zone for Tectona grandis should not be less than 2.44 x 2.44 m or more than 2.9 x 2.9 m, while Terminalia superba should be planted no less than 4.2 x 4.2 m or more than 5 x 5 m. The planting espacement at 5 x 5 m will improve stem form and growth.