First observation in the wild:	2008
Invasion stage:	spread
Spatial distribution:	isolated

Reproduction in the wild:	yes
Dispersion potential:	high
Natural habitats:	likely

More on invasiveness: The green ash is a early- to late-successional species of riparian forests, adapted to survive in flooded soils through a variety of physiological and morphological traits. In Central Europe, it is mainly observed in riparian mixed forests of Quercus robur, Ulmus spp. and Fraxinus excelsior, along the great rivers (Ulmenion minoris, 91F0 Natura 2000 habitat), an habitat that nearly disappeared from Belgium. Green ash has been recently discovered as isolated individuals in other type of riparian habitats in Western Belgium, along rivers and canals. It is also known to easily colonize disturbed sites when a seed source is available, both in its native and introduced range. Seeds are wind dispersed; birds or small mammals may also aid dispersal by caching seed.

Predation / Herbivory:	low
Competition:	likely
Disease transmission:	low
Genetic effects:	low

Nutrient cycling:	unknown
Physical alteration:	medium
Natural successions:	medium
Food web alteration:	low

More on impacts: The green ash can outcompete native species, overcome other trees and modify the vegetation structure in wide floodplains submitted to regular flooding events. It seems however to be less competitive in other riparian areas. As its preferred habitat is poorly represented in Belgium, green ash's capacity to cause environmental damages is uncertain. Plant extracts contain allelopathic compounds.

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