Wood Production in Gradual Shelter Wood Method

Wood harvesting through gradual shelter-wood method in uneven-aged forests of Northern Iran caused degradation of some forest areas. Recognizing ecological groups of every forest areas is considered as one of the management tools in restoration of applied forest areas. Hence, this paper pays to study the ecological groups of forest areas of about 75 hectares in Agozchal-Nowshahr. Bilateral index species to identify ecological groups and biodiversity index to compare the amount of biodiversity were used. To consider plant groups randomly, net dimensions of 150*100 and 40 sample fragments of 400 m 2 have been used. The study shows that there are 40 plant species in this area which are divided into four ecological groups: first (A), (Fagus orientalis L., and Epimedium pinnatum F.) second (B). (Alnus subcordata L., Acer cappadicicum B., and Lamium Alba). Third (C), (Acer cappadicicum B., Tamus communis L.) and forth (D), (Tilia begnifolia Stev.and Carex acuiformis L.). The analysis of variance showed that the two groups of A and D which are recognized with two tree index species of beech and linden respectively , had the least diversity (sympson ) and species richness ( margulave ) indexes had the most species uniformity index (kamargo) . The other plant groups relatively showed the same index of biodiversity

Investigation on Cryptococcus fagi (L.) population in relation to silvicultural characteristics of oriental beech forests (case study: Safaroud, Ramsar)

Cryptococcus fagi, the vector of Nectria sp., is one of the most important pests in beech forests which can cause beech bark disease. Because of its dispersion in the most beech forests of the northern Iran it should be taken under consideration. In this study, after forest survey, the infected area in watercatchment 30, district 5 of Safarod/Ramsar region were distinguished and 123 infected individual trees have been demarcated. Some characteristics such as d.b.h, height, infection intensity, structure and forest type have been determined. Results showed that, the most infected trees were categorized in small timber, but the highest infection intensity was observed in large timber trees. Also the pest high abundance can be seen in the small timber with regular structure. On the other hand, the stands with less stem density have been appropriated for most infection. The pure beech stands were more infected compare to mix stands. The pest abundance rate was higher in north and north-west directions. According to the results, although the disease symptoms are being observed, but no sever disease is recognized yet. As a matter of fact, it can be concluded that the pests are in their primary attack stage which could be controlled easily in this stage

Effect of light on quantitative and qualitative characteristics of hornbeam seedlings (Case study: Korkrood forest, Mazandaran)

Hornbeam is the most frequent species in forests of northern Iran. This paper aims to study the relationship between gap size and some quantitative and qualitative characteristics of hornbeam seedlings. For this purpose Khanikan district in Korkrood forest was selected in northern Iran. Four sizes of gap were selected based on silvicultural definitions including: area with less than 200 m², 200 to 500 m², 500 to 1000 m², and larger than 1000 m² and in each gap, 4 subplots each 2 m² were laid out. The current study was made in 2 phases: 1) study on light intensity using fish-eye camera, and 2) quantitative (including collar diameter and height) and qualitative characteristics of hornbeam seedlings. The obtained result showed that the intensity of light changed between 2 and 70 percent in different gaps and different locations of the gaps. The number of hornbeam seedlings increased with a relative increase in the light intensity initially and then decreased. Collar diameter and height of seedlings didn’t show significant differences among different light intensities. The number of seedlings was reduced significantly in the gaps larger than 500 m2. The best qualitative condition and the maximum number of hornbeam seedlings were observed in the gaps smaller than 200 m2