Hoofed animal's grass pulled up (4)
I believe the answer is:
deer
'hoofed animal's' is the definition.
(I've seen this before)
'grass pulled up' is the wordplay.
'grass' becomes 'reed' (I've seen this before).
'pulled up' is a reversal indicator.
'reed' reversed gives 'DEER'.
(Other definitions for deer that I've seen before include "Hoofed animals" , "Ruminant mammal with antlers and hooves" , "Antlered animal" , "Antlered mammal" , "The male is a stag" .)