Estimation of over- and Under- Size Merchantable Timber Volume of Populus deltoides Bartr

Populus deltoides is an important agroforestry tree species adopted by the farmers in North-West India. Though economic returns are comparatively better than rice-wheat rotation under wellmanaged conditions, poplar growers have suffered in recent past owing to their exploitation by the middlemen. The marketing is mostly done by grading of timber based on mid girth of logs as over-sized or under-sized logs. The present study was conducted in the central-plain region of Punjab, as existing timber volume and weight tables do not provide the information regarding proportion of over- or under-sized timber. The data on tree height, diameter at breast height was recorded on 83 randomly selected trees having girth at breast height (1.37 m from surface) ranging from 45 to 113 cm. The trees were felled and cut into logs of acceptable merchantable lengths. The data on log length, log girth (over and under bark) on both ends and at mid point, and log weight were recorded. The volume regression equations were developed on basis of diameter at breast height (DBH), and DBH and tree height. Further separate volume and weight tables were developed for over and under sized merchantable timber. These tables will be useful to the farmers, timber growers, wood contractors, state forest departments, research workers and the planners in their respective areas of concern for future plantation programmes.