Investigation of uneven-aged beech forest (semi selection cutting) to get ideal regeneration in the beech stands (Hyrcanian Beech Forests)

In this research, regeneration of the beech through aged under uneven-aged system was investigated in stands of native beech at Sangdeh Forests. A completely randomized design with five treatments and 36 1ha plots was applied. Tree Species in the field of the experimental design were respectively as follows: beech 66%, hornbeam 30%, cappadocian maple 1.8%, alder, torminalis clusii, mazzard cherry, maple, ash, elm and oak. Species composition in Gazane-chall research project is as follows: beech 71%, hornbeam 25%, torminalis clusii 1.20%, cappadocian maple 1%, mazzard cherry 0.5%, elm, ash and oak. Seven plot groups or seven structure groups namely: Typical uneven-aged stand, some deal uneven-aged stands, uneven-aged stands tending to even-aged from and homogeneity, evenaged stand in MT classes, even-aged in LT/MT classes, even-aged in LT classes and temporary decay were identified through the synthesis and structure classification of 20 plots in Talar-sarband research project based upon the histogram distribution of trees' classes (only for beech). For Gazane-chall research project, 9 plot groups or 9 structure groups were separated i.e., even-aged in LT/MT classes, even-aged stand in MT classes, even-aged in LT classes, even-aged in XLT/LT classes, uneven-aged stands tending to even-aged from and homogeneity, temporary decay, Initial uneven-aged or young stands in regeneration stage, some deal uneven-aged stands and typical uneven- -aged stand. Typology of the native beech stands with a number of 144 sub- plot 1.4 ha were determined using variables, borders and identification key with a synthesis on existent structure and classification in four classes including: Typical uneven _ aged stand, some deal uneven-aged stands, uneven-aged stands tending to even-aged from and homogeneity, and temporary decay. Final typology of the native beech stands was studied and prepared in both study areas. The identification key of the final native beech stands was also prepared in compilation of structure-mix and three compilation status namely: number per hectare, cross section per hectare-structure. For both research projects, 6 groups based on mixing, 9 groups based on structure and 5 groups based on richness (number per hectare and cross section per hectare) were separated. Typology of the regeneration cells were identified and presented on the basis of incorporation of tree Species of cells, composition and structure of the surrounding native mass (population). No significant differences were recorded for the studied variables and treatments in Gazane-chall research project. But in Talar-sarband research project, significant differences were found for average height of the seedlings and surface of the gaps in all treatments. Which may be due to the rotation of cutting as three rotation are required for each treatment to show the differences.