Far more problematic is the hybrid with another very close relative, giant knotweed (F. sachalinensis).

This tall plant, growing up to 2 metres, is often accompanied by the even taller giant knotweed (P sachalinense).

It also seemed highly specific, attacking only Japanese knotweed, giant knotweed and their hybrid.

Resveratrol is sold as capsules that contain extracts of red wine and giant knotweed, a plant found in China.

Crosses between Japanese knotweed and giant knotweed have occurred where the two species grow in close proximity.

Closely related species include giant knotweed (Fallopia sachalinensis, syn.

It was less keen (but did survive) on giant knotweed, and adults placed on anything else showed their displeasure by expiring.

Both Japanese knotweed and giant knotweed are important concentrated sources of resveratrol and its glucoside piceid, replacing grape byproducts.

The introduced Asian plants of Japanese and Giant Knotweed are common throughout the town and surrounding woodlands and are colloquially known as "elephant ears".

Despite being even bigger, giant knotweed is less of a problem than Japanese knotweed, but the hybrid, F. x bohemica, is just as bad as its mother, although not nearly as common - yet.

Vegetation on the shore lines of Lilla Värtan includes Alder, Purple loosestrife, Common Valerian, Yellow Loosestrife, Reed Canary-grass, Tall Fescue, Lesser Periwinkle, and Giant Knotweed.

Some knotweeds grow extremely quickly during the spring; giant knotweed can reach 4.5 m by summer, Japanese knotweed 3 m, and "dwarf" Himalayan knotweed 1.5-2 m. In Japan, Japanese knotweed is known as itadori, or "strong plant".

Closely related species include giant knotweed (Fallopia sachalinensis, syn.