Abstract:
Ceiba pentandra, Colagigantea,Lanneawelwitschii,Militia excelsa (all non-leguminous) and
Milletia zechiana (leguminous) are among the various tree species retained on cropping fields
in the Akuapem District of Ghana, but little is known of the actual contribution of these species
to soil fertility improvement.
Leaf litter samples from the above-mentioned non-leguminous species were analysed to
determine their nutrient content. Leaf litter production was also quantified monthly over a fourmonth
period and hence the potential contribution of the different types of leaf litter to the soil
nutrient pool was calculated.
Results from pot experiments, in which maize (Zea mays) was used as a test crop indicated that
when the leaf litter produced by the four non-leguminous species are used as mulch, the
nutrients contained in them are not readily available for plant growth. Nonetheless, studies of
soil chemical properties beneath tree canopy, at canopy edge and outside tree canopy suggest
that long term accumulation of leaf Utter from C. pentandra and L. wehvitschii results in higher
availability of nitrogen and phosphorus.
Millettia zechiana, on the other hand, was found to have nodulation ability and hence is
potentially capable of contributing to soil enrichment through biological nitrogen fixation.
