• Journal of Duhok University UoD
  • TARIQ K. SALIH *Dept. of Forestry, College of Agricultural Engineering Sciences, University of Duhok, Kurdistan Region-Iraq.
  • MUZAHIM Y. SAIED Dept. of Forestry, College of Agriculture and Forestry, University of Mosul-Iraq
  • SALIH T. WALI Dept. of Forestry, College of Agricultural Engineering Sciences, University of Duhok, Kurdistan Region-Iraq
Keywords: Completion factor, Competition indices, Diameter growth, Individual tree growth, potential growth


This study has two purposes; the first one is development of a new method in determining a competition factor for Pinus brutia trees grown in a stand, and the second one is development of a theoretical method for determination potential growth of individual trees within a stand. This potential growth can be used to estimate the growth of a tree as if it grows in a competition free area. Competition between trees has a strong effect on growth potential.  Dense forests need thinning to ensure providing the essential growth requirements. The developed factor can be used to give the answer for when and how much of stocking should be removed. Two samples of trees were selected, one from an open grown area and the other from forest stands. For each sample many regression equations were developed, for regressing, the diameter growth with different forms of diameter. The developed equations were undergone many tests of precision, to determine the one that best fits the dataset. At last the equation,, and equation  were finally selected for regressing the diameter growth with diameter at breast height for trees grown in a stand and open grown trees respectively. These selected equations were used to calculate the competition factor. Furthermore the equation; was finally selected among 23 others to be used for calculating the growth potential of trees grown within a stand.


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Author Biography

Journal of Duhok University UoD

Journal of Duhok University

University of Duhok

Kurdistan Region - Iraq


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How to Cite
UoD, J. of D. U., SALIH, T. K., SAIED, M. Y., & WALI, S. T. (2020). DETERMINATION OF COMPETITION FACTOR FOR TREE GROWTH WITHIN A STAND. Journal of Duhok University, 22(2), 177-188.
Agriculture and Veterinary Science

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