Agroforestry in the southern highlands of Tanzania
Kamasho, J.A.
Norwegian Journal of Agricultural Sciences ( 21, Suppl): 87-92
1995
Document Number: 516151
A maize-Leucaena leucocephala alley cropping system was studied on Uyole and Ismani soils in the Southern Highlands of Tanzania. L. leucocephala var. K8 was planted at 0.5 m within rows and 4 m between rows (6 rows) in April 1981. Hedgerow trees were pruned at height 2 m starting in late 1982, and thereafter twice (at 2-month intervals) per growing season over 9 yr. Maize was grown at 60x75 cm spacing in the alleys between the hedgerows, starting in the 1983-84 season, and yields measured 0.5, 1.25 and 2 m from the leucaena rows. Alley plots were either not mulched, or mulched with 2.5 t fresh mulch/ha. Maize was also grown in non-alley plots established next to leucaena hedgerow plots and mulched with 5 t fresh mulch/ha. All plots were fertilized with calcium ammonium nitrate at 0, 30 or 60 kg N/ha, applied in a split-plot design. The application of 5 t mulch/ha increased maize yield compared with no-mulch controls at both locations, but yields in the 2.5 t/ha treatment were only slightly higher than the no-mulch value. Application of N fertilizer also increased yields and there was an interaction between the effects of mulch and N application. Maize yield was reduced by nearly 20% at less than 1 m from the leucaena rows. Annual mulch production was 7 t/ha at Uyole and 4 t/ha at Ismani, and wood production after 9 yr at Uyole and 6 yr at Ismani was 45 and 22 msuperscript 3 stacked volume/ha, respectively. Data are also given on leucaena height and diameter growth.