Subject
- Agricultural pests -- Control -- Congresses31
- Insecticides -- Research10
- Pears -- Diseases and pests9
- Wood poles -- Fumigation9
- Wood poles -- Maintenance and repair9
- Wood poles -- Preservation9
- Vegetable gardening -- Oregon8
- Pear psylla -- Control5
- Beans -- Varieties4
- Winter wheat -- Fertilizers -- Oregon4
- Barred owl -- Reproduction3
- Beans -- Diseases and pests3
- Codling moth -- Control3
- Grass seed industry -- Oregon3
- Grasses -- Seeds -- Research -- Oregon3
- Machining3
- Northern spotted owl -- Reproduction3
- Poultry -- Diseases3
- Pullorum disease3
- Seed industry and trade -- Oregon3