Hi Heidi,
I believe that the weed in your photo is Bur Buttercup (Ranunculus testiculatus). It's a common weed found in Central Oregon. Now is the time to eliminate the plants before they go to seed as the plant develops very nasty burs.

You can use mechanical methods to eliminate the weed, such as hand pulling or digging. Also, putting down a layer of mulch may assist in reducing seed germination.

If necessary, you can use a post-emergent broadleaf weed killer (e.g. products containing 2, 4-D). The herbicide does become less effective once the plant begins flowering and setting seeds. Follow all label directions for application and be aware that chemical drift can cause damage to other plants so avoid using when windy.

Here are some links to information that you may find helpful to learn about this weed and how to eliminate it from your garden:

Common Weeds found in Central Oregon: Useful for weed identification.
https://extension.oregonstate.edu/sites/default/files/documents/11356/weed-photos-binder.pdf

A Northern Nevada Homeowner’s Guide to Identifying and Managing Bur Buttercup | Extension | University of Nevada, Reno (unr.edu)

Bur Buttercup | USU

Weed Control Handbook (ucdavis.edu)

If you need additional information, I recommend you call the Deschutes County OSU Extension office in Redmond at<personal data hidden> and ask to speak with Amy Jo Detweiler (oregonstate.edu). Amy Jo welcomes your home garden questions and is a great resource. She may have additional ideas for you.