Pest control

Asked October 2, 2017, 6:08 PM EDT

I have some creature digging holes in our lawns. The holes are about 3-4" in diameter, easily that deep (straight down) and then seem to tunnel horizontally, though I can't tell how far the tunnel goes. There's no dirt on top of the ground. Any idea what this could be?

Benton County Oregon

4 Responses

Ground squirrels could be the source of those holes. Here is a link http://ipm.ucanr.edu/PMG/PESTNOTES/pn7438.html to a California Extension site on one of our more common ground squirrel visitors here on the westside - California ground squirrels.
Feel free to write again if we need to do further diagnosis or chat about control options here in Oregon.

Thanks for your response. What control methods are used here in Oregon? Or, if the Extension Service does not have that information, who would be able to give me that kind of advice? Thanks for your help.

Depending on the scale of the problem (how many squirrels, how large an area), you may either consider DIY with retail-available anti-coagulant rodenticides or trapping. Because no toxicant "knows" what is swallowing it, you must follow the labeling restrictions to the letter in terms of how and when you place the baits. Trapping configurations and a sample plan for a baiting tool are in this (old but still useful) publication http://icwdm.org/handbook/rodents/ro_b151.pdf
The other option to consider is hiring a licensed Wildlife Control Operator http://www.dfw.state.or.us/wildlife/license_permits_apps/wildlife_control_operator_contacts.asp#WCO_... who offer the advantage of holding pesticide applicator licenses and thus have purchasing & application access to other toxicants (higher risk to non-target animals, thus the restriction to those who are trained and licensed to distribute them in a way to minimize/eliminate non-target hazards).
Ground squirrels are a little tricky due to their hibernation strategies. (See the table at the bottom of the UC Extension pub sent earlier). So timing matters - While the weather is still fine, you might still be able to access animals above ground/active in burrows - Once they go into their protected nests however, it's a matter of planning for a springtime strategy.

Okay. I'll bear that in mind. Thanks for your advice.