Effect of pine mistletoe on radial growth of crimean pine (Pinus nigra) in Turkey.

In this study, the influence of infection by pine mistletoe (Viscum album L. subsp. austriacum (Wiesb.) Volmann) on the radial growth of crimean pine (Pinus nigra Arnold) in Turkey was investigated. We built local residual treering- width chronologies using dendrochronogical techniques. Tree ring chronologies of uninfected (control) crimean pine were used to estimate potential radial growth characteristics in the “infected” crimean pine (light, moderate and severe infection groups). In 2005, increment cores were collected from 26 infected and 19 control dominant or co-dominant trees and annual radial growth indices from 1930-2005 were calculated for each infection group in a 14 point sampling. We compared radial growth in the uninfected trees with mean regional chronology. We found a strong decrease in radial growth in during the 1998-2005 period. The periodic average radial growth reduction (in %) from 1998 to 2005, respectively, were 0 for control, 26 for light, 39 for moderate and 63 for severe infection groups. It can be especially concluded that a severe degree of pine mistletoe attack has a negative effect on radial growth of the infected crimean pine trees.

Effect of defoliation by the pine processionary moth (PPM) on radial, height and volume growth of Crimean pine (Pinus nigra) trees in Turkey.

In this study, we assessed the effects of chronic defoliation on radial, height and volume growth of Crimean pine (Pinus nigra Arnold) trees of the pine processionary moth [Thaumetopoea wilkinsoni Tams (Lepidoptera:Thaumetopoeidae)] in western Turkey. Crimean pine tree ring chronologies were analyzed for evidence of the pine processionary moth (PPM). Tree ring widths from non-defoliated Crimean pine sample trees, which were not defoliated by PPM from 1998 to 2004, were used to estimate potential growth in the defoliated Crimean pine sample trees during the same time interval. In 2004, increment cores collected from 50 defoliated sample trees and 25 non-defoliated sample trees dominant or co-dominant trees. Annual radial growth indices from 1985-2004 calculated for each defoliated Crimean pine and non-defoliated Crimean pine group. We identified regional outbreaks of PPM by synchronous and sustained growth periods of Crimean pine trees. Growth functions of defoliated Crimean pine trees (3) and non-defoliated Crimean pine trees (2) were graphically compared as the cumulative sum of radial, height and volume increment. Two outbreak were identified in 1992 (1992 and 1993) and 1998 (1998-2004) in the study area. PPM caused a significance decrease (average 33%, p<0.05) in the annual radial increment in 1998-2004.

Predicting the above-ground biomass of crimean pine (Pinus nigra) stands in Turkey.

In this study, biomass equations are presented for crimean pine (Pinus nigra Arnold) stands within the Zonguldak forest region. A total of 44 sample plots, each of 0.04 ha were chosen in order to define the biomass equations of black pine, the most common needle leaved species in Turkey. A tree which is the most similar to mean tree according to basal area was cut in each sample area as a sample tree. Various models were tested, utilizing the diameter (d) and the height (h) as independent variables and the most suitable models were determined. Using these models, above-ground biomass amounts can easily be acquired for single trees and stands.

Effect of environmental factors on the productivity of crimean pine (Pinus nigra ssp. pallasiana) in Sutculer, Turkey.

This study was conducted on Pinus nigra sub sp. pallasiana commonly known as crimean pine. The purpose of this study was to determine the important site factors affecting the development of these forests in Sutculer district. This district experiences a transitional climate between Mediterranean and Continental regions. There is a strong water deficit in summer. The data was collected from 37 sample plots. It was analyzed statistically by using upper stand height as a dependent variable and some site characteristics as independent variables. The results revealed that there was only one important negative linear relationship between upper stand height and Ah organic matter. This result was uncommon. The reasons for this depend indirectly other site factors (aspect, slope position, altitude, slope degree and humus forms). This result was explained at 69.53% of total variance using these site factors by means of factor analysis (FA). After FA, these site factors were transferred to stepwise disciriminant analysis (SDA) to determine eigenvalue ratios of the bonitet models. As a result of SDA, three bonitets and five variables (3B5V) were found as the best model with 71.5 % of variance and 0.007 % significance level.