Possible Clues:

• Small club for use with mortar
• What a nuisance with the French to work with the mortar
• Mashing instrument
• It's a nuisance with the French to make ground in 9 across
• Mortar go-with
• Grinder - insect perhaps getting leaf half destroyed
• Small club for pounding substance in mortar
• What a nuisance the French can be with the mortar
• What a nuisance for the French to work with mortar!
• Starts to be a nuisance for one to work with mortar