In general, Sesbania out-performed Leucaena in terms of growth rate. The
best growth rates for Leucaena were noted at site 1 (Central Plateau) on
bottom soils and site 5 (Buberuka Highland) which is the same near volcanic
soil as site 7 for Sesbania. Average height for a 5 month Leucaena in Rwanda
is 80 cm [Westwood, 1986]. None of the farmers applied manure or fertilizer
to the fields on which the shrubs were planted. The average growth rates
(AGR) in cm/month for the shrubs at the sites are indicated above the bar
graphs of (Figs. 4a and 4b). Clearly, Sesbania exhibits faster growth rate
than Leucaena. To illustrate, Sesbania scored an average growth rate of
62.2cm/month as opposed to 27.4cm/month for Leucaena at the same
location. The average growth rates for the shrubs on the valley bottom soils
(sites 2 and 7 for Sesbania and sites 1 and 5 for leucaena) are superior to their
counterparts on the upland and mid-slope soils (Figs. 4a and 4b). Both
Leucaena and Sesbania showed significant growths over time and these
growth rates were consistently better on lowlands where soils are moist and
fertile sites 7 and 2 for Sesbania and 1 and 5 for Leucaena.