Found in forest, a long claw (5)
I believe the answer is:
talon
'claw' is the definition.
(I know that talon is a type of claw)
'found in forest a long' is the wordplay.
'found in' indicates the answer is hidden within the clue.
'TALON' is hidden within 'forest a long'.
(Other definitions for talon that I've seen before include "Hooker" , "Bird of prey's claw" , "one that grips" , "Hooked claw; cards left after deal" , "Eg, an eagle's claw" .)