Typically American tree and herb centre
I believe the answer is:
elmer
'typically american' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'tree and herb centre' is the wordplay.
'tree' becomes 'elm' (elm tree is a kind of tree).
'and' means one lot of letters go next to another.
'centre' means to look at the middle letters.
The central letters of 'herb' are 'er'.
'elm'+'er'='ELMER'
Can you help me to learn more?
(Other definitions for elmer that I've seen before include "name" , "Man" , "- - Gantry (book, film)" , "____ Rice, US dramatist" .)