Assessment of leaf biomass production of selected deciduous indigenous browse shrub in semi-arid ecological zone of Mwanga district, Tanzania

MSc Thesis

The major problem facing ruminant livestock production in semi-arid ecological zone is lack of adequate feed and of good quality throughout the year. The problem is more critical in the dry season. In semi-arid ecological zone leaf litter of shrubs and bushes are an important feed resource during the dry season. Grewia bicolor is the main deciduous indigenous browse shrub dominating the western lowland areas of Mwanga district. This study aimed at investigating the influence of season and lopping on re-growth potential, leaf biomass production and nutritive value of Grewia bicolor in western semiarid area of Mwanga district. The treatments were: T 1 control (where the G. bicolor plant was not- lopped), T 2 where G. bicolor plants was lopped at the start of short rain season (November), T 3 where G. bicolor plants was lopped at the start of long rain season (March). A complete randomized design was used in this study, where four replications were laid across a general slope and three treatments were applied in each replication. The study revealed that the local feed resources for grazing ruminants in the study area during the dry season were mainly leaf litter of deciduous browse shrubs, leaf litter of annual and perennial grasses, and some edible forbs. The leaf litter of G. bicolor deciduous browse shrub had high CP content ranging from 7 – 9 % while the understory grasses were low in CP (4 – 6 %). Lopping of G. bicolor increased leaf litter production from 94 to 217 kgDM/ha. It can be concluded that G. bicolor can be utilized to increase livestock production while undertaking some lopping techniques to increase leaf litter production and to maintain the balance between its canopy size and desirable understory grass species.

EPINAV (Enhancing Pro-poor Innovations in Natural Resource and Agriculture Value Chain)