Answer: It's just about impossible to prevent moles, but you can try several things to deter them. Some people drop used kitty litter down their holes with good success; others report success planting the mole plant, Euphorbia lathyrus, or castor-oil plants. (Castor beans are poisonous so use caution.) If the area you want to protect is small, fencing might do the trick. Build a fence about 6 inches high and 18 inches deep. There are also some commercial devices that emit a high-pitched sound, inaudible to humans, that frightens the creatures, or wind-activated whirlygig-type devices that cause vibrations in the ground.
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