Original scientific paper
Effect of Pruning on Diameter Growth in Pinus brutia Ten. Plantations in Turkey
Nesat Erkan
; Southwest Anatolian Forest Research Institute P.O.Box 264 07010 Antalya TURKEY
Erdogan Uzun
; Southwest Anatolian Forest Research Institute P.O.Box 264 07010 Antalya TURKEY
A. Cem Aydin
; Southwest Anatolian Forest Research Institute P.O.Box 264 07010 Antalya TURKEY
M. Necati Bas
; Southwest Anatolian Forest Research Institute P.O.Box 264 07010 Antalya TURKEY
Abstract
Pruning is a technique used to add value to trees growing in forest stands, allowing the formation of clear, knot-free wood. Although many factors affect timber value, knots are the primary cause of reduction in timber quality of conifers. On the other hand, pruning may also cause reduction in the rate of tree growth, depending on pruning intensity.The aim of this study is to assess the effects of different pruning intensities on DBH (diameter at breast height) growth of young Pinus brutia plantations. For this purpose, three field experimental sites each with different site qualities, were established in three different locations. Four different treatments were applied at each test site: 1) control, no pruning of branches, 2) pruning up to 25% of tree height, 3) pruning up to 50% of tree height, and 4) pruning up to 75% of tree height. The effects of pruning on DBH growth were observed over a period of 14 years. At »Bük« test site, which has the poorest site quality, only those specimens pruned up to 75% of tree height showed significant reduction in DBH growth compared to the control. However, at »Nebiler« and »Kursunlu« test sites, specimens pruned both up to 50% and 75% of tree height showed statistically significant decrease in DBH growth. To recover from pruning stress in terms of DBH growth rate, it took trees 6 years at the poorest test site and 4 years at the relatively better test sites. This indicates that site quality of plantation sites accounts for not only DBH growth differences between sites, but also recovery rate of trees from any disturbances. Results showed that for those trees pruned up to 75% of their height, total DBH growth was reduced by between 6.5% and 9.0% after 14 years compared to the control at the test sites. No negative effect from pruning on DBH increment was observed in the first growing season. This may be due to earlier storage of nutrition in different parts of trees, thereby enabling them to compensate for the stress of crown reduction during the first growing season following pruning.
Keywords
pruning; Pinus brutia; diameter growth; growth reduction
Hrčak ID:
173836
URI
Publication date:
1.6.2016.
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