Seedling grading is one of the main aspects of producing good quality seedling in forest nursery. It is obvious that good quality seedlings would have highly survival and performance in field after out planting. This study was conducted to grade Acer velutinum and Alnus glutinosa seedling in Shanderman and Safrabasteh forest nurseries in Guilan province. For each species, 100 seedlings were selected randomly from seedbed. Collar diameter, height, number of root and leaf area of seedlings were

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... asured. The results indicated that there was significant correlation at 1% level, between collar diameter with number of roots, leaf area and seedling height. Furthermore, it is cleared that the seedling could be graded by collar diameter in four classes. Suitable collar diameter for Alnus glutinosa and Acer velutinum were 6-8 mm. and 10-14 mm, respectively.