Tree roughly embraced by writer (5)
I believe the answer is:
pecan
'tree' is the definition.
(pecan tree is a kind of tree)
'roughly embraced by writer' is the wordplay.
'roughly' becomes 'ca'.
'embraced by' indicates putting letters inside.
'writer' becomes 'pen' (I've seen this before).
'ca' placed within 'pen' is 'PECAN'.
(Other definitions for pecan that I've seen before include "Oval nut of south central United States" , "Walnut-like nut" , "Type of nut" , "of nuts" , "Pinkish-brown nut used in American pie" .)