Fool with plan to pull up grass (6)
I believe the answer is:
pampas
'grass' is the definition.
(I've seen this before)
'fool with plan to pull up' is the wordplay.
'fool' becomes 'sap' (synonyms).
'with' is a charade indicator (letters next to each other).
'plan' becomes 'map' (plan can mean a map of something).
'to pull up' shows that the letters should be reversed in order (I've seen 'pulled up' mean this).
'sap'+'map'='sapmap'
'sapmap' backwards is 'PAMPAS'.
(Other definitions for pampas that I've seen before include "Treeless plain(s)" , "Great plains of S America (6)" , "Grassy plains of Argentine" , "South American plains" , "South American grassland" .)