Environmental factors affecting establishment and expansion of the invasive alien species of tree of heaven (Ailanthus altissima) in Seoripool Park, Seoul

Abstract

Abstract Tree of heaven (Ailanthus altissima Swingle) as an invasive alien plant, appeared usually in the disturbed locations such as road‐side, incised slope, and trampling path‐side. They appeared abundantly in the trampling path‐side but they did not appear or were rare in the interior of forest. Density and importance value of tree of heaven were proportionate to the relative light intensity measured according to distance from the trampling path toward forest interior and closely related to the breadth of trampling path as well. They were associated with annual, other exotic species or ruderal plants well. Distributional pattern of mature trees of them in the study area and its surrounding environments implied that they were introduced intentionally. Size class distribution of them showed that they are in expansion and artificial interferences such as, installing physical training space and developing hiking course functioned as trigger factors in their invasion and expansion. The results support the ...