Provenance Variation and Seed Zone Delimitation of Acer velutinum (Boiss.) Seedlings in the Hyrcanian Forest

Persian Maple, Acer velutinum, has a wide distribution in Hyrcanian forests. In this investigation, a provenance test (two years) was conducted with the open-pollinated seeds of seven populations collected from different altitudinal gradients. In the first year, all populations' seedling height and diameter/height ratio decreased significantly. However, no significant difference in collar diameter was detected in the populations. Seedlings from the populations of the lower altitudes (<700m) tended to grow taller compared to those from the higher altitudes (>1200m). The productivity in the first year indicated that some populations originating from the middle altitudes had higher production. In contrast, during the first growing season, there were no significant differences in survival rate among the various origins. In the second year, the seedlings originated from the middle altitudes as well as the local province (cite the elevation) had the highest survival rate. To minimize the mortality rate, we categorized four altitudinal groups and recommended restoring the genetic type of coverage of the original forest, using the seed from the same zone, because seeds from other zones have increased mortality.