Possible Clues:

• Conjuror's cry
• Man with battle to find tricky words?
• Sounds like silage near poster not exactly words of magic
• Dairy product skimmed quickly, as if by magic
• Top heresy about magician's cry
• The magic words to press 18 down under the hay, by the sound of it
• Conjurer's exclamation
• Sounds like fodder to follow the conjurer, in a manner of speaking for the press (3, 6)
• Conjurer's words at key moment
• Grass speaking rapidly: that's the trick