The effect of altitude and nurse type on the success rate of Brant`s oak and wild Pistachio seeding in Dalab, Ilam forests

In this study, the rate of seedling emergence from direct seeding of Brant`s oak (Quercus brantii Lindl.) and wild pistachio (Pistacia atlantica Desf.) in Dalab forests of Ilam in two altitude and five regeneration establishment positions during two years 2018-2019 was examined. For this, six sites were selected at an altitude of 1400 and 1550 m above sea level with the same aspects. In each site, a transect was implemented perpendicular to the slope, and on it regeneration establishment positions including “under tree crown”, “under shrub”, ‘under bushes”, “next to the rock” and bare spaces, observing three replicates were established. At each regeneration establishment position 12 holes were dug. In the dug holes, the seeds of the mentioned species were planted in the winter of 2017. The number of green holes and the number of emerged seedlings were counted during the spring and summer of 2018 and 2019 years. The results showed that the effect of sampling year, sampling season, altitude, regeneration establishment position and interaction effect of altitude and regeneration establishment position on the percentage of green holes is significant. The percentage of green holes decreased in the second year compared to the first year and in summer compared to spring. The highest percentage of seedling emergence was at lower altitudes and under tree crowns. The performance of Stones and bushes was better than shrubs which ranked after tree crowns. It was concluded that if seed sowing is done according to the natural pattern of regeneration, successful results can be hoped for.