Sticky stuff siren can produce? (5)
I believe the answer is:
resin
'sticky stuff' is the definition.
(sticky substance)
'siren can produce?' is the wordplay.
'can produce?' indicates anagramming the letters (I've seen this in other clues).
'siren' anagrammed gives 'RESIN'.
(Other definitions for resin that I've seen before include "Synthetic substance" , "Sticky exudation from trees" , "stuff that's sticky" , "Synthetic compound" , "It exudes from pines" .)