You can bet it's made of wood (5)
I believe the answer is:
stake
'you can bet' is the definition.
I can't judge whether this defines the answer.
'it's made of wood' is the wordplay.
'made of' indicates an anagram.
'wood' becomes 'ake' (I can't explain this - if you can you should believe this answer much more).
'ts' is an anagram of 'st'.
'st'+'ake'='STAKE'
Can you help me to learn more?
(Other definitions for stake that I've seen before include "A wager or pointed pole" , "Money gambled" , "Share (in a business); post" , "Wager; post" , "A bet or sharpened stick" .)