Elimination trial of 10 Poplar clones (Populus nigra) in Kermanshah province

In order to select and introduce the promissing clones of Populus nigra, 10 clones were planted 3*3 m in two research stations (Mehregan and Eslamabad) of Kermanshah province. The statistical design of the experiment was randomized complete block with three replicates. At the end of each growing season, diameter at breast height and height of trees were measured. Moreover, at the last year other factors such as collar diameter, media diameter, top diameter and weight of trees were measured as well. The results after 8 years showed that Populus nigra 62.154, P.n. 56.75, P.n. betulifolia, P.n. mehrgan, P.n. 56. 32 and P.n. 56. 52 are the most promissing clones. The mean diameter of clones varied between 20.7 and 21.9 cm, mean height between 15.2 and 16.9 m and mean volume increment varied between 32.3 and 39.2 m3ha-1y-1