Subject
- 4-H clubs21
- Agricultural pests -- Control -- Congresses16
- Oregon State University -- Curricula16
- Mineral industries -- Oregon11
- Natural gas -- Prospecting -- Oregon9
- Petroleum -- Prospecting -- Oregon9
- Geology -- Oregon4
- Earthquakes -- Oregon -- Portland3
- Forests and forestry -- Northwest, Pacific3
- Geology, Stratigraphic3
- Continental shelf -- Oregon2
- Forage plants -- Oregon2
- Forest management2
- Forest policy -- United States -- Bibliography2
- Forest products industry -- Northwest, Pacific2
- Forest reserves -- United States -- Bibliography2
- Forests and forestry -- United States -- Bibliography2
- Geology -- Oregon -- Dayville Quadrangle2
- Geothermal resources -- Oregon2
- Gold -- Economic aspects2