Defects in Properties of wood are used as common indicators for grading logs. In this study, the logs of various woody species from ten different forestry projects have been evaluated based on their measured defects.The results of this study showed that the average diameter of acceptable knot for the first 3 meters of the trunks was 2.8 cm for maple (the least value) and 7 cm for hornbeam (the highest value), respectively. Moreover, the knotless portion of the first 10-meter-Iong trunks was 12.2, 32.4 and 20 percent for hornbeam, elm and beech, respectively. As for pith decay of trunk, the least and the highest values were 56 and 84 percent which were associated with maple and elm, respectively. As for trunks with bent defect, oak and basswood showed the lowest value (7 percent), while hornbeam showed the highest value (18 percent). This value for beech was about 10 percent. Bole taper (decrease of bole diameter of less than 2 cm per meter of length) was 65 percent in maple (the lowest value), and 96 percent in oak (the highest value). This value for beech was 75 percent. The lowest and highest values for defect of interlocked fibers were observed in boles of alder (68 percent) and oak (91 percent), respectively. The percentage of boles with interlocked fibers for beech was 89 percent. As for trunk with irregular annual ring, it was shown that hornbeam had the lowest value (82 percent). However, 94 percent of the other woody species didn't show such a defect. Finally, the lowest and highest percentage values for trunks with abnormal annual rings were 16.1 and 24.3 for oak and elm species, respectively.

30 plots (0.1 ha.) were selected in three different altitudes (400-600m, 600-800m and 800-1000m) in Lajim, North of Iran. In every macroplot 9 microplots (2m2) and 1 microplot (l00m2) were selected. In macroplots the total of trees, vegetation layer, soil condition and the factors such as deforestation and physiographic and in microplots the quantitative and qualitative natural regeneration of all trees especially hornbeam were studied. In this investigation after analysing the data the results were as follow:Generally, the frequency share of tree species is Carpinus 44%, Fagus 24%, Parrotio 14%, Diospiros 9% respectively. The mean percent frequency of Carpinus regeneration is about 56% and the other tree species is 44%. The altitude, slope, aspect, crown cover and vegetation layer did not have considerable affect on hornbeam regeneration. In destructed Carpino-fagetum community, hornbeam replaced beech. Soil scarification increased hornbeam regeneration. Increasing drought also decreased hornbeam regeneration. In Parrotio -Carpinetum community, hornbeam regeneration was remarkable. Besides that, due to human being and stock, the regeneration of superior species were decreased and the inferior and invading species, such as Parrotio persica and Diospyrus lotus were increased.Because hornbeam, by its leaves, produces high quality humus layer, improving the soil condition, and provides an important role in treatment and prunning of the dominant species and produce long fiber for pulpwood, therefore the encouragement and development of this species should be highly considered. In Parrotio-Carpinetum communities by implementing the appropriate silvicultural practices, particularly the encouragement of natural regeneration, the adaptable species, especially hornbeam can replace the inferior tree species. Thus, in addition to the development of these communities, the conservation, biological and economical values can be enhanced.

Tilia platyphyllos which belongs to Tiliaceae family has aromatic flowers. The flowers were collected from Research Institute of Forests and Rangelands and extracted by hexane solvent. The absolute of linden was prepared by using Ethyl alcohol. The absolute were analyzed by GC/MS. Nineteen compounds representing 96% of the absolute were identified of which Dihydrocarvone (29%), Limonene (12.9%), Caryophtllene (26%) and Carvone (6%) were the major constituents.

Because there is not enough information on the percentage of seed germination of native broad-leaved species of Caspian Forests of Iran, seed sowing is usually done with extra density. For this reason, most of the produced seedlings are thin and have low height and diameter growth rate. In case of sowing seeds with low density, the seedling production is not profitable due to few numbers of seedlings per area unit of nursery. The current trial was conducted, using Randomized Complete Blocks Design with three replicates for each species to obtain an ideal density of seed sowing and increase seedlings quality.Four species were tested including Quereus eastaneifolia, Tilia begonifolia, Aeer velutinum and Fraxinus excelsior. Four seed mass treatments per squar meter of nursery were applied for each species which differ for different species. The plot area was three squar meters. After measuring weight of 100 seeds of each species, the seed mass of each treatment was sawn inside of the plots along five rows. Only the seedlings grown on the three middle rows were considered and studied, leaving the first and the last rows as bufer lines. Space between the rows and between the plots was 20 and 30 cm, respectively. Two seed sowing seasons were planned: spring and autumn. According to the results achieved, autumn was the best, so all of the measurements and evaluations were made in that season. The differences between the seed density treatments were not significant, for all species. Best seed density for Q. eastaneifolia, T begonifolia, A. velutinum and F. excelsior was 500, 100,40 and 50 g/cm2, respectively.

This research studies quantities and qualities of Lime-tree. In order to determine these characteristics, at western parts of Mazanderan province, nine sites were selected. Within each sites, three elevations were distinguished and in each sites three plots, each one hectare (100*100m) were established. In each plot, following features were recorded: height above the sea level, direction of slops and the percent of slops, quantities and qualities characteristics. In order to study the generation of Lime-tree five microplotes were selected, each of them 100 m2 (10*10m).The results have indicated that Lime-tree goes up in a wide range of environmental conditions. This species has distributed from low elevations to high elevations and in different slops, especially northern, eastern and northeastern slops. Also this species has formed two forest types-Limetree -Beech and Beech-Limetree - in the high elevation in Royan3. Quantitive studies showed that the best conditions of frequency and density has been observed in Royan3. This site has the least basel area and crown coverage. In the northern conditions of Lime-tree distribution is better than other slops. The best quality of condition has seen in north-eastern, eastern and western slops. The best generation has been recorded in the north-eastern.

Yew (Taxus baccata L.) is one of the five conifer speciess, which grows naturally in Gilan's forests. This species extends from 220 to 1400 meters above sea level and can grow in pure and mixed stands with beech, maple, alder and etc. The objective of this study is to evaluate the status of yew natural regeneration. Cluster sampling method was carried out on 20 hectars of yew forest, which was located between 1180 to 1400 meters above sea level. The obtained results showed that the yew seedling grows both with seed and sprout. The density of yew seedling was one seedling per 10 square meters. The number percentage of yew seedlings at 0-5 mm. Collar diameter (CD) class was the highest while at 10-15mm. CD class was the lowest. Abundance of yew sprouts on the forest, showed that the severe environmental conditions which prevent the yew seedling to developed. The results of seedling height showed that the except of 0-5 CD class, the height of seedlings from seed were higher than seedlings from sprout.

In order to investigation the effect of mechanical and chemical treatments on seed dormancy and its germination in Tilia platyphyllos, a completely randomized design was used with 14 treatments in 4 replications. Treatments included hot water 80°c for 10 minutes, warm water 60°C for 30 minutes, 30% Sulfuric acid for 10 minutes, 15% Sulfuric acid for 20 minutes, 1%H2O2 for 20 minutes, 1% H2O2 for 40 minutes, control treatment including stratification in decayed saw dust and river sand. Results showed that best germination rate belonged to hot 80°c water for 10minutes in the period of 45 days in decayed sawdust and the lowest rate of germination in treatment belonged to 30% Sulfuric acid for 10 minutes, 1%H2O2 for 20 and 40 minutes in the period of 90 days and control treatment including 180 days stratification in sawdust and sand.

In order to study the effects of some environmental variables on the quantitative and qualitative characteristics of large-leaved lime (Tilia platyphyllos Scop.) in the forests of the western parts of Mazanderan province, 9 experimental sites were selected. Within each site, three elevations were identified. Also in each site three plots, each of one hectare area (l00×l00m), in total 27 plots were establishd. Observations as well as experimental results indicated that large-leaved lime extends in a wide range of environmental conditions. This species is distributed from low elevations to high ones and in different exposures; especially northern, eastern and northeastern slopes. The results also revealed that large-leaved lime grows in semi-deep to shallow soils with a medium amount of nutrient content. In most sites, soil texture is clay to clay-silt with pH varying between 5.9 and 7.6. Average annual precipitation varies between 1100 and 1311 mm, with average annual mean temperature varying between 8.1 and 15.2°C.Categorization of sites was accomplished through hierarchical cluster analyse and based on the effects of environmental variables on the quantitative and qualitative characteristics. The quantitative and qualitative characteristics play an important role in site classification because of being affected by environmental variables.There is relationship between ecological characteristics (soil, climate, altitude and slope sides) and quantitative characteristics (diameter at breast height, diameter of crown, total height, height of first branch, as well as height of bi-branch) and qualitative characteristics (stem bending, convolution, as well as stem symmetry of crown).

In order to study the typology of Lime-tree (Tilia platyphyllus Scop. Subsp. caucasica (Rupr.)) at western parts of Mazanderan province, 9 sites were selected. Within each site, three elevations were distinguished and in each site three plots, each one hectare (100*100m), were established. In each plot, following features were recorded: height above the sea level, direction of slops and the percent of slops. Diameter of breast and total height of trees were measured for all spices. The stratification and typology of tree spices has been done based on frequency of spices, presented by Gorji(1379). The results indicated that Lime-tree was observed with these spices: Fagus orientalis Lipsky., Carpinus betulus L., Acer velutium Boiss., Acer cappodicicum Gred., Parotia persica (DC.) C.A. Neyer., Diospyrus lotus L., Alnus substrata C.A.Mey., Fraxinus excelsior Scneere., Cerasus avium L., Sorbus terminals L., Buxus hyrcanus Pojark., Quercus castanaefilia C.A. Mey and Ulmus glabra Ruas. The main type was Lime-tree, Beech and the secondary type was Beech, Lime-tree with Hoenbeam. The frequency of Lime-tree is observed in forest types with Beech and Hoenbeam more then forest types with Iron tree and Date plum. This shows that distribution of Lime-tree in climax stands more then its distribution in destroyed stands.