Title
Wood physical properties and tracheid dimensions of non-native softwoods in Iran
Authors
MOHAMMAD FARSI and MAJID KIAEI

Received December 14, 2012
Published Volume 48 Issue 5-6 May-June
Keywords softwood species, seed source, physical properties, tracheid dimensions, biometrical properties

Abstract
This study was conducted to investigate some physical properties (basic density, volumetric shrinkage), tracheid dimensions (tracheid length, tracheid diameter, lumen diameter, and cell wall thickness) and biometrical properties (flexibility coefficient, slenderness coefficient and Runkel coefficient) of 9 species of non-native softwoods of the world imported to and grown in the northern region of Iran. For this purpose, 27 healthy trees from scots pine species with seed origins in Spain, Serbia (part of former Yugoslavia), Armenia, spruce species with seed source in Serbia, Lajim and Kelardasht, and species of black pine, yellow pine and larch from a Vanemek-Neka site in northern Iran were selected randomly and a disk was cut from each one at breast height. Test samples were cut from the disks to measure physical properties (based on the ISO standard), tracheid dimensions (using the Franklin method) and biometrical indexes. The ANOVA results showed a significant difference among softwood species in terms of physical properties, tracheid dimensions and biometrical properties. There was no significant difference in Runkel coefficient. Seed source had some meaningful effects on the physical properties, tracheid dimensions and biometrical properties of scots pine (except flexibility coefficient and Runkel coefficient) and spruce wood (except basic density and Runkel coefficient). The relationship between various wood properties and quantitative features (survival, height and diameter) of the trees showed no significant correlation between these mentioned traits in non-native softwood species. All of the investigated species presented important indicators for the production of paper in terms of biometrical coefficients. However, planting scots pine with seed origins in Serbia and Armenia seems to be more suitable due to higher wood production over a short time period and better compatibility with the site conditions.