In article , Scott L. Hadley
writes
If you would be so kind, what is twitch? I finally have to ask,
following many years occasional encounters with this (apparently
British) word. If it is one of the perennial, creeping, invasive
grasses such as our witch grass, if is definitely a problem, but not
beyond reach. The close mowing done in much of Britain should help,
but I dasn't venture further till I know what twitch is!

Strictly, couch grass, Agropyron repens, but used by gardeners to mean
more or less any invasive creeping grass.
--
Kay Easton

Edward's earthworm page:
http://www.scarboro.demon.co.uk/edward/index.htm