Models for oriental spruce and scots pine mixed stands in Trabzon and Giresun forest district directorates

The importance mixed-species forest stands has recently been stimulated in parallel with the shift in emphasis from timber production to other products and services of forest ecosystem. The knowledge of growth and yield is crucial factor for management of mixed stands that have preferable attributes for pure stands.The models estimates essentially growth and yield of trees and stand that have different ecological attributes. These estimation are used for inventory updating, estimating stand structure and stand productivity and evaluating silvicultural alternatives, and in general for decision support in forest management and planning.In this study, the data were comprehended 161 sample pots with different stand ages, site index, density and mixture percentage and 306 stem analysis of dominant and co-dominant trees for oriental spruce and scots pine mixed stands in Trabzon and Giresun Forest District Directorates. This study aimed to develop stand yield model, individual tree growth model and diameter distribution model. Stand yield model were assessed as Density-Variable Yield Table, and used for estimation of remaining, removal and total stands. Diameter distribution models provide detailed estimation in diameter classes. Individual tree growth models were developed as distance independent and distance dependent models. Also, site index models and mortality models based logistic function were constructed.