ACER VELUTINUM BOISS بررسي جوان چوب و تغييرات طول الياف در افراپلت

Evaluation on juvenile period and fiber length variation of Maple wood (Acer velutinum Boiss)

Three maple trees (Acer velutinum Boiss), which randomly were cut from research forest of Gorgan University were used in this study. Average annual growth ring width of juvenile wood in breast height was obtained 5.43 mm Yearly diameter increases and average fiber length was calculated 10.86mm and 789.60 respectively. Regarding to the fiber length classification based on Metcalfe & Chalk (1983), fiber length of juvenile maple is grouping in short size category. Analysis of variance was conducted on collected data, which results showed 15th annual growth ring was the end of juvenile period in the stem. This result corresponds to the Shiokura formula. Average annual growth ring width and yearly diameter increase as well as mean fiber length in mature wood was obtained 3.5mm and 984.5 pm, respectively. Fiber length of mature wood is grouping in medium size category. Total trunk diameter without bark in the breast height of stem in the age of 27 was 24.69cm. The portion of juvenile and mature wood to the total trunk diameter was 65.97 and 34.02 percent, respectively. Results showed that maple wood in the age of 27 is not recommended using in furniture manufacturing, because of the large portion of juvenile wood in the stem, meanwhile for chemical conversion will not appear a problem.