Subject
- Furrow irrigation1
- Grape leafroll virus -- Northwest, Pacific1
- Grapes -- Diseases and pests -- Northwest, Pacific1
- Insects as carriers of plant disease -- Northwest, Pacific1
- Mealybugs -- Northwest, Pacific1
- Nutrient pollution of water1
- Phosphatic fertilizers -- Environmental aspects1
- Polyacrylamide1
- Soil-binding1