Answer: The mole population is cyclical in that it tends to rise and then fall off naturally. Moles are not harmful to plants, so unless they are creating a dangerous situation with their tunnels, it is better to leave them alone. (If you find something is eating the roots of your plants then it is most likely voles.) The most effective control for moles is traps. Here is some information about moles and trapping you may find interesting. You will probably need to cut and paste the complete url into your browser to make it work correctly.
I ihope this helps.
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