A Re-Assessment of a Fire Protection Experiment in North-Eastern Ghana Savanna

Abstract

Three plots in Northern Guinea Savanna were enumerated and then clear-felled in 1950. Since then 1 plot has been completely protected, a 2nd has been burned annually early in the dry season, and a 3rd plot has been burned annually late in the dry season. In 1976-1977 there were 202 trees ha-1 (.gtoreq. 30 cm girth) on the protected plot, 42 trees ha-1 on the early burned plot and 20 trees ha-1 on the late burned plot. Corresponding figures for basal area are 3.43, 0.51, 0.24 m2 ha-1. The basal area of grass on both the burned plots has remained constant at about 13% since 1960; the basal area of grass on the protected plot has continued to decline and was 6.3% in 1976. Grass biomass at the end of the growing season in 1976 was 182 g m-2 on the protected plot, and 260 g m-2 and 144 g m-2 on the early and late burned plots, respectively. There were 73 spp. of vascular plants on the protected plot in 1977, and 53 and 44, respectively, on the early and late burned plots. Only slight differences in the soils were observed, although the protected plot had significantly more organic matter and total N. The results are compared with those of similar experiments elsewhere in Africa, and recommendations are made for improved experimental design.