Subject
- Forests and forestry -- Northwest, Pacific6
- Forests and forestry -- Research -- Northwest, Pacific6
- Pacific Northwest Forest and Range Experiment Station (Portland, Or.)6
- Forest soils4
- Columbia River3
- Forage plants -- Oregon3
- Burning of land2
- Ceanothus velutinus2
- Dissertations, Academic -- United States -- Bibliography -- Catalogs2
- Douglas fir2
- Douglas fir -- Diseases and pests2
- Forest ecology2
- Forests and forestry -- Oregon2
- Humus2
- Microorganisms2
- Nitrogen -- Metabolism2
- Oceanography -- Research2
- Peppermint -- Diseases and pests2
- Plant ecology2
- Subterranean clover2