Harvesting timber in the natural forests
1990
Abeli, W.S. | NORAD (sponsor) | Mgeni, A.S.M. | Abeli, W.S. | Chamshama, S.A.O | Kowero, G.S. (ed.)
At present, natural forests are being utilized for timber and fuel-wood production besides serving as soil and water catchment areas. Where indiscriminate logging has taken place, environmental hazards like landslides, soil and eater erosion have resulted. If these forests are to continue being of multiple uses, proper logging plans are necessary.Compared to plantations, logging production in the natural forests is low due to low harvestable volume per hectare, improper logging gear, poor road network general poor working conditions.Most of the work operations in the natural forests are performed manually on a task work basis. Studies on cutting in miombo forests when using two-man crosscut saw and power saw have found the daily cutting production to be 4.2m3/day and 29.2m3/day respectively. In tropical high forest, when using an axe the cutting production was 9.1m3/day. Cutting costs when using power saws and two-man crosscut saws in miombo forests are at present estimated to be Shs. 54.30m3/and Shs. 43.00/m3 respectively.Skidding studies have shown that when using four-wheel industrial (County) tractors in miombo woodland forests, production was 8.5m3/ha as compared to 7.5m3/ha when using D7 crawler tractor in tropical high forests; estimated skidding costs are Shs. 206.15/m3 and Shs. 487.00/m3 respectively.Trucks used for hauling logs in the natural forests are ordinary flat deck trucks without side stakes. Poor truck condition coupled with manual loading resulted to 7t trucks being loaded only 4.7-4.9m3/trip. Hauling costs varied depending on the hauling distance and the load size. Where the hauling distance was about 70 km roundtrip, hauling costs are estimated to be Shs. 1,373/m3.
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