The Effect of Pruning and Thinning on The Growth of OAK Coppice Quercus aegilops L.

Othman Kamil Aref, Muhammed Sa’adi Gharib  &  Latif Haji Hasan   

 college of agricultural sciences-University of Sulaimani, Bakrajo Street, Sulaimaniyah-Iraq


This study was performed on the eastern aspect facing Azmir Mountains that locating the northeast of Sulaimani City, during the growing seasons of 2005, 2006 and 2007. The coppices of the dominated oak Quercus aegilops were treated by silvicultural practices, included pruning and thinning, in four different levels. The objective of this study was to evaluate the effect of pruning and thinning on height and diameter growth of the oak species. Generally, the results showed that pruning to ½ of the coppice height P3 was significantly superior on pruning to ¼ P1 and pruning to one-third 1/3 of the coppice height (P2) on height growth parameter, while there were no significant differences between P2 and P3 on diameter growth. Regarding the thinning, the results generally revealed a significant increasing in the growth of height and diameter of the oak coppices of the three thinning levels in comparing to the un-thinned stump. Regarding the dual interactions, the results showed that P3C3 was significantly superior on the height growth parameter.                                                                                                                                                   

Key Words:  pruning, thinning, growth, oak, coppice 


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