First observation in the wild:	1924
Invasion stage:	spread
Spatial distribution:	restricted

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

More on invasiveness: As other Asiatic knotweeds, giant knotweed colonises a wide range of environments, with a predilection for moist and nitrogen-rich soils. It prefers sunny places or semi-shaded habitats. This pioneer plant proliferates both in ruderal and semi-natural habitats, including riparian areas and open forests. Stem and rhizomes may easily split in small pieces; fragments are able to regenerate a plant, provided a node is present. Giant knotweed produces a small amount of viable seeds, but seedlings are seldom observed in the wild. Transport of garden waste and soil contaminated with rhizomes are the major dispersal modes. Where the plant is widely consolidated on river banks it is also spread by floods and can easily colonise downstream.

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

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

More on impacts: Fallopia sachalinensis is able to monopolize space and to form dense and persistent populations. It can outcompete most of native herbaceous plant species thanks to early seasonal development, high growth rate and productivity, abundant leaf cover, allelochemical production and clonal spread associated with an extraordinarily high rate of proliferation of below-ground organs. It can even outcompete Fallopia japonica on alluvial riverbanks. Its development reduces plant and invertebrate species diversity, alters habitat for fish and wildlife, change ligth and energy conditions of the ecosystem and favours river bank erosion during the winter. It can also break through tarmac and thin layers of concrete and can penetrate some flood defences.

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