Grass seen next to light brown climbing palm (6)
I believe the answer is:
rattan
'climbing palm' is the definition.
(type of climbing plant)
'grass seen next to light brown' is the wordplay.
'grass' becomes 'rat' (both can mean a snitch or informer).
'seen next to' says to put letters next to each other.
'light brown' becomes 'tan' (tan is a light brown colour).
'rat'+'tan'='RATTAN'
(Other definitions for rattan that I've seen before include "Pliable palm stems used in weaving" , "Wickerwork material" , "Kind of cane used in furniture" , "A form of cane" , "Palm cane used in wickerwork" .)