Answer: First you need to check the label on the mole repellent you used, to see if it says it would be toxic to plants or to certain plants. If not, then there may be another reason for the needles to be browning. There may be root damage (if the moles tunneled next to the roots and damaged them as a result, or if instead of moles there are voles -- voles actually eat plant roots). Or, there may be a pest or disease problem. I would suggest you consult with your local county extension to try to obtain a more specific diagnosis. Based on knowing that, they can help you decide how to proceed. If a chemical control is needed, they will have the most up to date recommendations on what to use and how/when to use it for maximum results. And, always read the label.
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