Effect of ground slope, stump diameter and species on stump height and volume for forest logging in District 2, Nav-Asalem watershed

Minimizing of logging residuals is the first and basic rule of forest harvesting. In this research effect of ground slope, stump diameter and species on stump height and volume were studied district 2 from Nav-Asalem forest area in the north of Iran. For this reason 68 felled trees from each three ground slope classes (< 20%, 20-50% and >50%) were selected using random sampling design and stump heights and volumes were calculated from Newton formula. ANOVA and Duncan test were used for analysis of data and compare means. The results showed that mean of stump height in the study area were 37.9 cm. Besides, 77% of stump heights were more than 32.5cm. 37 percent of stumps, ratio of stump height to stump diameter (H/D) were lower than 0.5. Each three studied factors (ground slope, tree diameter and specie) were significant effect on stump height. Stump height were increased Whit increasing of ground slop and tree diameter. Stump heights in beech, hornbeam, maple and alder were measured 38.7, 39.9, 26.5 and 25.6cm. 4.34±0.75 percent of selected trees volume were remained in forest as stump waste volume. Education and control of felling operation personnel can be useful to reducing stump height and increasing timbers.