Browsing by Author "Mugasha, W.A"

Now showing 1 - 5 of 5

Effects of thinning on growth, yield and stem quality of pinus patula at Sao hill forest plantation, Mufindi district, Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2022) Nguyeje, P.C; Chamshama, S.A.O.; Mugasha, W.A
Pinus patula is one of the most important plantation species grown in Eastern and Southern Africa. Its growth rate and yield vary considerably depending on site conditions, management techniques and genetic quality of the trees. It has been suspected that thinning of softwood plantations in Tanzania has been neglected resulting in lower standing volume being distributed into many small trees of poor form. This study assessed the effects of thinning on growth, yield and stem quality of Pinus patula at Sao Hill Forest Plantation located in Southern Highland part of Tanzania. In a systematically established plots; diameter of all trees, a total height of three trees and stem quality of four classes were recorded. An independent t-test was used to test for significant difference in stand parameters and Mann-Whitney U test was used to test stem quality between thinned and unthinned stand. Results showed that thinning significantly increased growth and yield of Pinus patula. Thinning improves stem quality by 9% resulting in trees having straight and good stem form. Thinned stands yielded higher volume than unthinned stands. Therefore, this study recommends that pine plantations should be timely thinned as per used thinning schedule to ensure that more volume is attained.
Pine resin productivity at Sao hill forest plantation, Southern Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2021) Beleko, S; Malimbwi, R.E; Mugasha, W.A; Balama, C; Mpiri, A
A study on resin productivity from Pinus patula and P. elliottii was carried out at Sao Hill Forest Plantation. Four and three compartments for Pinus patula and P. elliottii, respectively covering age between 5 and 25 years were selected. In each compartment, three plots (12m × 12m) were systematically established. All trees in each plot were measured for diameter at breast height (Dbh) and three trees (smallest, medium and largest in diameter) measured for total height and crown diameter. All trees in treatment plots were tapped for resin. Weighing and re-wounding of tapped trees was done after every ten days in ten sessions. The findings show that annual resin yield ranged from 0.56kg tree -1 to 1.32kg tree -1 and from 0.47kg tree -1 to 1.98kg tree -1 for P. patula P. elliottii, respectively. The Dbh and crown diameter were important predictors resin production. Over 31% of annual resin production was explained by stand level variables. It was recommended that integration of resin tapping into the current schemes of timber will improve the contribution of the forest sector in economic growth. Further, introduction of resin tapping may be an attractive option for early income generation while waiting trees to attain the rotation age.
Rotation age and fibre length of pinus patula at sao hill forest plantation, Tanzania
(Tanzania Forestry Research Institute (TAFORI) and Tanzania Forest Fund (TaFF)) Laswai, F; Malimbwi, R.E; Chamshama, S.A.O; Abdallah, J.M; Balama, C.; Pima, N.E; Mugasha, W.A; Mauya, E
Rotation age and fibre length of pinus patula at sao hill forest plantation, Tanzania
(Tanzania Forestry Research Institute (TAFORI) and Tanzania Forest Fund (TaFF), 2018) Laswai, F; Malimbwi, R.E; Chamshama, S.A.O; Abdallah, J.M; Balama, C.; Pima, N.E; Mugasha, W.A; Mauya, E
This study determined the rotation age of Pinus patula grown at Sao Hill forest plantation based on growth, yield, wood properties, and economic analysis. Previous Technical Orders on rotation age were not based on these considerations. Growth, yield, wood properties, revenue, and management costs data were collected and analysed using standard procedures. The results indicate that there were fewer and lighter prunings and thinnings than specified in the respective schedules. Many trees were found to have breast height diameter below 40 cm in all compartments except one. Growth and yield results showed that for P. patula grown at Sao Hill, the equity point of Mean Annual Increment (MAI) and Current Annual Increment (CAI) were achieved at between 16 and 17 years with the maximum MAI being maintained until about 20 years. Basic density and mechanical properties showed that strong wood was obtained when trees were 16 years and above and these properties increased with age. The mean fibre length for 5 - 25 years old P. patula was found to range from 2.29 to 3.53 mm and increased with age. Fibre lengths from 11 years and above exceed the minimum (3 mm) considered suitable for pulp and paper production. Based on economic analysis, net present value (NPV) was attained at between 16 and 17 years. Based on considerations of growth and yield, wood properties and economics of rotation age; P. patula from Sao Hill is recommended to be harvested at 18 years for timber and 11 years for pulp and paper production.
Stump diameter : a potential predictor of removed biomass through tree cutting
(Tanzania Journal of Forestry and Nature Conservation) Mugasha, W.A; Mauya, E; Karlsson, K; Malimbwi, R.E.