Hi Micah,The tick in your photo is an adult female from the genus Dermacentor. In Oregon, the Dermacentor species most likely to bite people are the Rocky Mountain wood tick (Dermacentor andersoni), the western dog tick (Dermacentor similis) and the Pacific Coast tick (Dermacentor occidentalis). I cannot tell which species that one is from the photos.

Luckily, no ticks in the genus Dermacentor transmit Lyme disease, so you don't need to worry about that. Dermacentor ticks can transmit other diseases such as Rocky Mountain spotted fever and tularemia though, but cases of these diseases being transmitted by tick bites in Oregon are extremely rare. If you have concerns about this, you could consult your doctor.

Hope that helps!