بررسي مقايسه اي جنگل كاري خالص و آميخته صنوبر از نظر توليد كمي و كيفي چوب

Comparison of pure and mixed stands of Populus deltoides

This forest were established in two forms (pure and mixed stands) with Populus deltoids in 1987. 20 plots were selected for consideration (10 plots in each stand). The diameter at breast height and height of trees, length and diameter of crown, healthy, vitality, volume and growth of trees and soil in all plots were considered. 12 trees (6 trees in each stand) were cut for wood physical and chemical analyzing. The results are following: Thickness of lifter layer was more in pure populus stand. The situation of soil in twolus stand. The quality of trees in pure stand was be stands were similar. The growth of trees was more in pure poputter than mixed stand. The fiber lumen was more in wood of pure stand, therefore, the burst and tensil resistance and breaking length in this stand was more than mixed stand. The wood density in mixed stand greater than pure stand. As the percent of lignin and extraction material in pure stand is less and its cellulos is more than mixed stand, therefore pure stand is more suitable for pulpwood. As a whole, because the mixed stand having variety production resistance against pestes and fungi and more uses of soil and space better than pure stand, but the base of different conditions of climate, site and uses of wood the selection of pure or mixed stands is different. In this area the pure stands of populus in some objects especial for pulpwood more better than mixed stands.