Weed; cut short (4)
I believe the answer is:
dock
I believe this clue is a double definition.
'weed' is the first definition.
(type of weed)
'cut short' is the second definition.
(as in docking a dog's tail)
(Other definitions for dock that I've seen before include "Where one might repair cutter" , "Harbour" , "Use this for nettle stings" , "Antidote to nettle stings" , "weed bit of station > where Richard Roe stood" .)