The Flora of Derbyshire - Checklist, Maps and Sample Accounts

THIS IS A DRAFT

The species account below is an early version, drafted around 2003. It has been provided here to aid understanding, but please be aware it may not fully tally with the up-to-date map and statistics shown below.

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Dates
First year: 1950
Latest year: 2004

County Status
Established

Family
Polygonaceae

Total records held
27

Grid Square Count

1987-2007	Ever
Monads: 9	11
Tetrads: 9	10
Hectads: 8	12

Conservation Status

Account last edited
Oct 17 2003

Explanation of terms

Species Details

Giant Knotweed is a very rare established perennial of waste ground, roadsides and riverbanks. It occurs scattered through our area from Chisworth (SJ9992) and Beauchief (SK3281) in the north to Cromford (SK3057) and Milford (SK3444) in the south. It is sometimes grown in gardens from where it escapes to form robust rhizomatous thickets. These thickets can be larger than those produced by Japanese Knotweed (XXF. japonica) so it is lucky the plant does not seem as invasive as its smaller cousin. It is a native of eastern Asia.