Forest roads are the most important elements of forestry projects, the management, supervision, care, and only access way to the forest for mechanized harvesting and using other services of forests. The aim of this study was to compare the current annual increment of basal area in different distances from the road in northern forests of Iran. For this purpose, 50 plots were established in 5 dis...

We studied the relationships among 5-year radial (diameter and basal area) growth of red oak (genus Quercus, subgenus Erythrobalanus) crop trees and predictor variables representing individual tree vigor, distance-dependant competition measures, and distance-independent competition measures. The red oaks we examined are representative of the commercially and ecologically important oak species o...

A graph that contains a spanning tree of diameter at most t clearly admits a tree t-spanner, since a tree t-spanner of a graph G is a sub tree of G such that the distance between pairs of vertices in the tree is at most t times their distance in G. In this paper, graphs that admit a tree t-spanner of diameter at most t + 1 are studied. For t equal to 1 or 2 the problem has been solved. For t = ...

in this research, the effect of tension wood formation in populus nigra on its anatomical characteristics was studied. vessel element and ray frequency (n/mm²), vessel diameter and ray dimensions were measured in both normal and tension wood. furthermore, the formation of gelatinous layer (g-layer) in the fibers of tension wood was studied. the results showed that the vessel proportion and diam...

For maintaining of Zagros forests role in wild life, water and soil conservation, the suitable solutions and methods for assessing the existing conditions and planning for management of this forests should be given. To detection of suitable sampling method to study tree Diameter at Breath Height in the northern Zagros forest, Blake forest, in Baneeh region, Kurdistan province, and west of Iran ...

This paper presents results concerning climatic conditions affecting diameter growth of Sitka spruce introduced to Baltic Pomerania (Sławno Forest District). A relatively high homogeneity of tree-ring series permitted to construct on their basis the tree-ring chronology of Sitka spruce. A significant positive correlation was found between radial increments of Sitka spruce and air temperatures o...

the present study was conducted to determine the most appropriate tree species planted in the same ecological condition considering different variables at darabkola forest, mazandran province. for this purpose, the success of planted species (maple, walnut, oak, pine, ash and elm) was assessed according to ninecriteria (soil nitrogen, soil phosphorus, soil potassium, leaf nitrogen, leaf phospho...

For maintaining of Zagros forests role in wild life, water and soil conservation, the suitable solutions and methods for assessing the existing conditions and planning for management of this forests should be given. To detection of suitable sampling method to study tree Diameter at Breath Height in the northern Zagros forest, Blake forest, in Baneeh region, Kurdistan province, and west of Iran ...

For maintaining of Zagros forests role in wild life, water and soil conservation, the suitable solutions and methods for assessing the existing conditions and planning for management of this forests should be given. To detection of suitable sampling method to study tree Diameter at Breath Height in the northern Zagros forest, Blake forest, in Baneeh region, Kurdistan province, and west of Iran ...