First observation in the wild:	1939
Invasion stage:	spread
Spatial distribution:	isolated

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

More on invasiveness: Invasive populations of Russian olive in North America typically thrive in semi-arid riparian habitats with low flood frequency and intensity, but also in old fields, meadows and sparse woodlands. In Europe, it is found both in disturbed areas and in open semi-natural habitats, often in coastal areas (dunes, salt marshes, grasslands, etc.). The plant originates from cultivation: it is commonly used as an ornamental and is planted in gardens and public green areas (e.g. windbreak and erosion control). Plant fruits are readily eaten and disseminated by many species of birds. Seeds are hard and dormant at maturity and require a period of cool, moist stratification, or possibly scarification, for germination. Species dispersion and establishment in Belgium is poorly documented.

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

Nutrient cycling:	high
Physical alteration:	likely
Natural successions:	likely
Food web alteration:	low

More on impacts: In North America, Russian olive invades preferentially beneath the canopy of native riparian trees or within dense herbaceous vegetation, where it forms self-replacing stands. As opposed to most weedy plants, it has life-history attributes typical of later-successional species; it is very competitive and can form monospecific populations with high stem densities that displace native vegetation and interfere with natural plant successions. Because it is capable of fixing nitrogen in its roots, it may contribute significant additional nitrogen to the ecosystems that it invades. However, in Belgium as in other West European countries, dense populations of Russian olive are rarely observed in the wild.

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