Answer: First off you need to make sure whether you have a mole or voles. The easiest way to tell the difference is that moles do not eat plant roots. Moles eat only insects such as grubs, and worms. Moles are also somewhat beneficial in that they help aerate the soil. There are many home remedies for moles, but as you have seen they rarely work well.
Here is information about moles and voles and how to control them. One other interesting aspect of this type of problem is that the populations do tend to have natural highs and lows, so the population will peak and then drop off naturally.
I hope this helps.
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