Accurate estimation of forest biomass, productivity, yield regulation, and carbon stock relies on precise volume prediction at both individual tree and stand levels. This study, titled "Comparison of Standing and After Felled Volume of Timber in Teak Plantation in the Sagarnath Forest Development Project, Nepal," was conducted in the Sarlahi district's Sagarnath forest development project (SFDP). The primary objective of this research is to calculate the disparity in timber volume before and after harvesting in a Teak Forest. The 2D felling site provided 150 sample trees for data collection. Before felling, the diameter at breast height (DBH) of standing trees was measured using a diameter tape, tree height with a range finder, and tree quality class was determined based on community forest inventory guidelines. After felling, the total length of the log, girth at the mid-length of the log, as well as the length and diameter of hollowness and depth of buttress, were measured using a measuring tape. To compute timber volume before felling, the formula defined in the Community Forest Resource Inventory Guideline, 2061, was utilized, while the quarter girth formula was employed to calculate timber volume after felling. The findings indicated an overestimation of 696.80 cubic feet of timber before harvesting. A 95% confidence interval F test demonstrated a significant difference in timber volume before and after felling. There was a loss of 14.58 cu. ft of timber volume due to hollowness in the tree, and 83.10 cu. ft of timber was lost due to buttresses. Likewise, a difference in volume was observed based on quality class due to inaccurate classification.
The particular attention should be given to forest inventory measurements to ensure they are conducted without bias, using appropriate instruments and comprehensive training, while minimizing measurement variation to achieve precise estimates. Lastly, employing skilled manpower during estimating and harvesting operations is strongly advised to ensure efficiency and accuracy in these processes.