Raccoons and lawn destruction - Ask Extension
This winter we have raccoon’s digging holes in our lawn, my research is telling me they are digging for grub worms. What is the best way to either k...
Knowledgebase
Raccoons and lawn destruction #858015
Asked January 28, 2024, 7:41 PM EST
This winter we have raccoon’s digging holes in our lawn, my research is telling me they are digging for grub worms. What is the best way to either kill grub worms without harming the raccoons or keep the raccoons away from our yard/lawn?
Marion County Oregon
Expert Response
I'm hoping to connect you with Dr. Kowalewski, our turf expert, to help you with ways to reduce populations of grubs in the lawn. His email is <personal data hidden>
You are correct that raccoons, but also skunks, are known for divoting lawns in their quest for tasty and nutritious grubs. Beyond reducing grub production of the lawn itself, the next but more challenging approach would be exclusion of the animals from your yard or lawn area. Exclusion of skunks is a little easier because they don't climb as well as raccoon, so a shorter fence can keep them out. With raccoons or skunks, running an electric hotwire around the yard at the appropriate height can help. Raccoons get in trouble with people in numerous ways, and to exclude usually means a hotwire on the top of the privacy or border fence and then looking for other means of entry - Their climbing means that overhanging branches-to-roof-to-downspout can be highways of movement, etc. - Thus to truly keep them out, a good bit of site-specific sleuthing can be involved.
Hopefully the easier route will be to manage the lawn to reduce the attraction.
You are correct that raccoons, but also skunks, are known for divoting lawns in their quest for tasty and nutritious grubs. Beyond reducing grub production of the lawn itself, the next but more challenging approach would be exclusion of the animals from your yard or lawn area. Exclusion of skunks is a little easier because they don't climb as well as raccoon, so a shorter fence can keep them out. With raccoons or skunks, running an electric hotwire around the yard at the appropriate height can help. Raccoons get in trouble with people in numerous ways, and to exclude usually means a hotwire on the top of the privacy or border fence and then looking for other means of entry - Their climbing means that overhanging branches-to-roof-to-downspout can be highways of movement, etc. - Thus to truly keep them out, a good bit of site-specific sleuthing can be involved.
Hopefully the easier route will be to manage the lawn to reduce the attraction.
I would identify the grub first. There are white grubs and crane fly larvae in OR. Both are soil living grubs for most of their life cycle. Both can be found in the soil this time of year.
Insecticide for grubs should be applied in the summer (July or August). Insecticides for crane fly should be applied in the winter (December and January). Below is more information on both insects…
https://pnwhandbooks.org/insect/hort/turfgrass/turfgrass-white-grub
https://diggermagazine.com/protecting-lawns-against-european-chafer/
https://pnwhandbooks.org/insect/hort/turfgrass/turfgrass-crane-fly
https://extension.oregonstate.edu/catalog/pub/em-9296-managing-crane-fly-lawns
