Wetland Plants of Oregon and Washington by 
Western Garden Book by 
Encyclopedia of Northwest Native Plants for Gardens and Landscapes by 
Trees and Shrubs of the Pacific Northwest by Native Plants and Trees of Oregon - This is a document put out by the State of Oregon that gives examples of plants and trees that are native to Oregon.
Native Plant Society of Oregon - Founded in 1961, this organization focuses on plant and habitat conservation.
Oregon Flora Project - Serves as the primary steward of Oregon's botanical information (OSU Herbarium): has an interactive Plant Atlas of Oregon to see plant distribution; a photo gallery; rare plant guide; flora of Oregon; a comprehensive list of the native plants of Oregon; and a link for the Oregon wildflowers app.
Native and Naturalized Woody Plants of Oregon - A list of the native and naturalized plants in Oregon.
Audobon Native Plants Database - Enter zipcode and find native plants that attract birds.
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