The effect of aspect and seeding position on the seedling emergence and survival of wild pistachio, maple and almond by direct seeding in Ilam forests

This research aimed at studying the seedling emergence and survival rate of Pistacia atlantica, Acer monspessulanum and Amygdalus orientalis by direct seeding in Dalab forests of Ilam with two aspects and five seeding positions (nurse type). For this purpose, six sites were selected in the north- and south-facing slopes with the same altitude. In each site, one transect was established perpendicular to the slope, and the seeding positions including “tree”, “shrub”, ‘bush”, “rock” and bare spaces, by observing three replicates were determined. At each seeding position, 12 holes were dug and the seeds of the mentioned species were planted. The number of seedlings during the spring and summer of 2018 and 2019 years was counted. According to the results, the number of seedling of P. atlantica decreased in the second year compared to the first year and in summer compared to spring. The highest percentage of holes with seedlings of P. atlantica was found in northern aspect and under tree crown and next to the rock. The highest percentage of holes with A. monspessulanum seedlings was under tree crowns and shrubs. A. orientalis did not react to any of the examined factors. The most and least share of the seedling emergence were belonged to P. atlantica and A. monspessulanum, repectively. It was concluded that the rate of seedling emergence changes under the effects of aspects and seeding positions, so to increase the emergence rate of seedlings, it is better to sow in the field in more suitable seeding position in any aspect.