Subject
- Agricultural pests -- Control -- Congresses145
- Pears -- Diseases and pests125
- Pear psylla -- Control45
- Pear37
- Codling moth -- Control29
- Insecticides -- Research14
- Pear -- Storage12
- Pear -- Diseases and pests11
- Pear -- Diseases and pests -- Control -- Oregon -- Willamette River Valley10
- Pear -- Pruning9
- Apple industry -- Oregon -- Hood River Valley -- Cost of operation8
- Pear -- Diseases and pests -- Oregon8
- Pear -- Ripening8
- Pear industry -- Oregon -- Hood River Valley -- Cost of operation8
- Pear psylla8
- Spraying and dusting in agriculture -- Oregon -- Willamette River Valley8
- Two-spotted spider mite -- Control7
- Apples -- Diseases and pests6
- Fruit-culture -- Oregon -- Hood River Valley -- Cost of operation6
- Pesticides -- Application -- Oregon -- Willamette River Valley6