Can moles kill pine trees

Asked August 19, 2018, 8:49 PM EDT

I have what I have been told are red pines and Australian pines in my back yard. We had several arborists here to give their opinion as to why the pines were dying. We were told that they are not native so they were subject to disease. We were also told that there were too many other trees that were blocking the light to the pines. However, when you walk in my woods, your foot sinks due to what I am sure are moles. I will contact two other universities to solve this problem but I hope you can do it first. Five years ago, I took out more than 20 40-foot pines at a cost of over $5,000 hoping the arborists I spoke to were right. I don't think they were. Last night I opened up a water hose for an hour and there was no water standing. Can you tell me if moles can kill pine trees? Please look at my soil. If it is moles, can you tell me how to get rid of them for good? Thank you. Mike Borgen 651-600-1512.

Washington County Minnesota nuisance wildlife possible moles

3 Responses

Thank you for the question. No photo was attached to your question so I'll include some information on accurately diagnosing the presence of moles and their activity in the landscape. A mole’s diet is mostly insects and earthworms. Moles make tunnels in the lawn and landscape while searching for insects, mainly earthworms and grubs and they will not feed on plants. The likelihood that they have caused the tree problems is low. Here are good publications from Indiana's DNR and Penn State Extension about moles and control options: https://www.in.gov/dnr/fishwild/5740.htm and https://extension.psu.edu/moles.
It is important to realize that you can't control this mammal for good. Even if you are successful in reducing or eliminating a current situation with moles, your efforts will be short-lived. As long as food resources and unoccupied habitat remain in place, it soon will be filled by other moles seeking territory to occupy. These small mammals require constant and on-going attention if you want to try to control them— there’s no such thing as once-and-done treatment.

I did find a publication on wildlife damage to hardwood plantations, but mole damage was described in terms of tunneling creating air pockets that can cause roots from young trees to dry out. Older, established trees with larger, more extensive root systems like yours would be less susceptible to this: https://www.extension.purdue.edu/extmedia/fnr/fnr-216.pdf

To summarize, I sympathize with your situation, but we can't tell you what is wrong with your trees. It's probably not caused by moles. If it's been 5 years since your trees were evaluated and they are still in decline, you may want to get another opinion from a certified arborist. We have a good publication on how to hire this professional: https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional


Thank you for contacting Extension.

Hi Anita,

Maybe instead of diagnosing from afar you may want to see what is going on here?

Mike Borgen
651-600-1512

Extension Master Gardeners are volunteers of the University of Minnesota. They do not provide onsite consultation at private homes. As volunteers, they donate their time to educate communities and citizens in best home gardening practices for the greater good. You can do a soil test to see if there is a problem with your soil. Visit this web site for information: http://soiltest.cfans.umn.edu/ Also here is a link to the home page of the certified arborists in our state. You can put in your zip code to narrow the search to certified arborists in your area: http://www.treesaregood.org/ Also, what you were told about sunlight being needed for your trees to grow is correct so if they are shaded, no amount of water or nutrients will make them healthier.