My mother has lost her lillies many times in the past due to moles. She was told to use juicy fruit gum because the moles would find the sweet gum irresistable. Moles are unable to digest the gum acting as a plug and so they die.
It really works it's not messy and it's cheap! Just place a half stick of unwrapped juicy fruit gum into a mole hole and wait.
Another was to rid moles in your yard is to get rid of the grubs. Interseeding white clover with your grass also prevents grubs.