Native plants are a gardeners dream: local, tolerant, and inviting to wildlife. The Native Plant Society of Oregon lists several each year that are threatened or endangered. We selected these two:

The Western Lily is a vibrant red plant that flowers from June to August, attracts hummingbirds, and appreciates direct sunlight. It is listed as endangered federally and in Oregon, with less than 3000 plants flowering per year.

The Kincaid Lupine, a purplish lupine, flowers April to June and has fallen victim to agricultural and urban encroachment on its native prairie habitat. The Kincaid Lupine hosts the larvae of the Blue Butterfly, which was thought to be extinct but is now listed as endangered. Kincaid Lupine is listed as threatened.

If you are fond of a particular type of plant, ask your nursery if there is a similar native variety that you can grow instead.

Resources
Rare and endangered plants list from the Native Plant Society of Oregon

Native plant selection guide at Portland Online

Bosky Dell's recipes using native plants. Bosky Dell coupon for 10% off.

Gardening Project #1: Eat From Your Yard
Gardening Project #2: Grow a Rain Garden with Farmington Gardens