Fallopia sachalinensis Giant Knotweed

A large rhizomatous perennial, native to eastern Asia, which is very similar to Japanese Knotweed (Fallopia japonica) but usually taller with larger leaves (>12cm and often >20cm) that are heart-shaped (cordate) at their base (not trucate) and have long hairs on their underside. It grows in similar palces to Japanese Knotweed but is much less common. It was introduced to Britain as a garden plant in 1869 but because of it large size it was rarely grown. It was found naturalised in county Antrim in 1896 and tehn about seven years later in Shropshire. Most plants in Britain are functionally female but male plants do occur. It is a tetraploid (2n=44) that will hybridise with Japanese Knotweed, which is octoploid (2n=88), to form a hybrid (Fallopia x bohemica) which is usually 2n=66. It has been noted in several locations throughout West Glamorgan and may be under recorded.

Neophyte

Also known as Reynoutria sachalinensis (F.Schmidt)