بررسي كمي و كيفي كشت آزمايشي گونه هاي بلندمازو، داغداغان و گردو در چمستان (مازندران )

Quantitative and qualitative characteristics of Oak, Nettle tree and Walnut experimental plantations of Chamestan (Mazandaran).

In this research, the qualitative and quantitative characteristics of Oak (Quercus castaneifolia), Nettle tree (Celtis australis) and Walnut (Juglans regia) were investigated in experimental plantation. Two-years old seedlings of species were planted in separated groups in 4x4 meter spacing as a part of a research project "Group plantation of industrial fast growing trees" at 1983. Diameter at breast height (dbh), total height, crown and trunk height were measured in 2005. The results indicated that survival in 23-years old trees of oak was 73.2% and for nettle tree and walnut were 97.1, 85.7 percent, respectively. Mean height of oak, nettle tree and walnut were 19.67, 11.48 and 15.96 m, repectively. The annual height increment of oak, nettle tree and walnut were 81.9, 47.9 and 66.5 cm, respectively. The mean dbh were 26.7, 11.2 and 17.9 cm for oak, nettle tree and walnut. The volume was 287.9 m^3 ha^-1 for oak, 39.4 m^3 ha^-1 for nettle and 128.6 m^3 ha^-1 for walnut. Volume increment was calculated 12.5 m^3 ha^-1y^-1 for oak, 1.6 m^3 ha^-1 y^-1 for nettle tree and 5.36 m^3 ha^-1y^-1 for walnut.