Investigation on distibution and some silvicultural charactristics of wild service tree (Sorbus torminalis) in Sangdeh Forest

Abstract

This research was conducted in 40000 ha of Mazandaran Central Forest (south of Caspian sea) in order to determine the distribution and some silvicultural characteristics of wild service tree (Sorbus torminalis L. Crantz). The forests were evaluated in four altitudinal profiles, stretched from northeast (NE) to southwest (SW), from lowland to upland (top of Alborz mountain). Wherever a Sorbus torminalis had been found, a circular 0.1 ha sample plot lied down. In 65 sample plots, habitat characteristics such as soil condition, slop, aspect and altitude was recorded. Some studied silvicultural characteristics of 185 individuals of wild service tree, includes: collar diameter, diameter at breast height (dbh), length of main trunk and total height. Moreover crown cover were evaluated in each plot. Climatic data of three climatological stations within the research area were used to determine the relationship between wild service tree distribution and climatic traits. The results showed that dbh, main trunk length and total height of wild service trees were 46.96 cm, 10.52 m and 19.96 m respectively. Majority of the studied wild service trees (42%) were on west exposed mixed stands of Fageto-Carpinetum or Fageto-Carpinetum, with Quercus types, 28% of these were on north exposed pure young beech stands. Frequency of wild servis trees with diameter more than 50 cm was greater than those with diameter lower than 20 cm. Correlation between soil depth and sorbus frequency was negatively significant (p

Keywords

• Sorbus torminalis
• distrubiution
• climatic
• Soil
• crown canopy
• height
• diameter