small-holder timber production: tree inventories/biomass surveys international workshop
1. SMALL-HOLDER TIMBER PRODUCTION: TREE INVENTORIES/BIOMASS SURVEYS INTERNATIONAL WORKSHOP ON SMALL-HOLDER TIMBER PRODUCTION ICRAF HOUSE 29 TH NOVEMBER 2004 PAUL M. NJUGUNA
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9. Comparison between 1993 and 1998 inventories 17.07m 3 7.5m 3 Usable Vol/farm (30% of Vol/ha) Up 107% 19.9m 3 9.6m 3 Vol/Ha Up 128% 56.9m 3 25m 3 Vol/farm Up 59% 397 250 Trees/Ha Up 73% 1137 656 Trees per farm difference 1998 1993
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12. Tree shapes used for Farm based Surveys..(1,2, 3, 4) Computing usable volume (stem volume from stump to tip) ln(v)=a+b ln(d) V-usable volume (dm3) D-diameter at breast height (cm) a ad b are constants constants and are for different tree forms Tree type parameter (a) Parameter(b) Source 1 -2.2945 2.5703 Laasasenaho 1982 2 -1.7322 2.3992 Pukkala 1989 3 -1.6493 2.3567 Pukkala 1989 4 -1.6840 2.2406 Pukkala 1989 Equations used to calculate tree volumes and constant for the four form factors used .
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14. Grevillea Boundary Planting in Giaki Area-Meru Central Silvicultural Operations such as thinning not done since the tree were not meantfor timber production at initiation .