Start chopping wood for money (4)
I believe the answer is:
cash
'for money' is the definition.
(cash is a type of money)
'start chopping wood' is the wordplay.
'start' says to take the initial letters.
'wood' becomes 'ash' (wood from an ash tree).
The first letter of 'chopping' is 'c'.
'c'+'ash'='CASH'
(Other definitions for cash that I've seen before include "Brass" , "Spondulicks" , ""Readies"" , "Funds" , "Ready money" .)