To preserve fodder, use saline, gets good with age ultimately (8)
I believe the answer is:
ensilage
'to preserve fodder' is the definition.
I can't judge whether this definition defines the answer.
'use saline gets good with age ultimately' is the wordplay.
'use' is an anagram indicator.
'gets' means one lot of letters go next to another.
'good' becomes 'g' (abbreviation).
'with' is a charade indicator (letters next to each other).
'ultimately' indicates one should take the final letters.
The last letter of 'age' is 'e'.
'saline' with letters rearranged gives 'ensila'.
'ensila'+'g'+'e'='ENSILAGE'
Can you help me to learn more?
(Other definitions for ensilage that I've seen before include "Making fodder" , "fermentation" , "Store fodder in silos" .)