Moles tunnel under lawns in search of food. Moles generally eat earthworms, grubs and insects. Typically, moles are solitary animals and use a series of tunnels in the quest for food. A mole does have a main tunnel that leads back to the den area. While there are chemical baits on the market, the most effective method for ridding a lawn of moles is a harpoon trap. The trap is set across the main tunnel, and when the mole trips the mechanism, it is caught and killed.
Identify all the mole tunnels in the lawn. These are located by raised tunnel areas in the grass. In most cases, these tunnels can be found in the early morning. Moles travel during the evening hours under the lawn.
Stomp all tunnels flat with your feet. This action will cause the mole to reconstruct tunnels. You may have to wait until the next morning to identify the most traveled tunnels.
Set the harpoon trap across the tunnel that is reconstructed. There may be more than one. Choose the best option. Catching a mole may take several attempts.
Push the ground stakes of the trap into the soil on either side of the tunnel. Insert the metal trip mechanism into the raised portion of the mole tunnel. Various types of harpoon traps will have different-sized trip mechanisms. Consult the instructions from your particular trap manufacturer.
Pull back on the arming spring mechanism to set the trap. Leave the trap alone until it trips. This may take until the next morning. If the trap does not trip, you may have to reposition the trap. It may take several attempts of stomping down the tunnels until you find the tunnel most traveled.