Subject
- Water conservation15
- Soil conservation -- Oregon -- Willamette River Valley8
- Upper Willamette Resource Conservation and Development Project8
- Water resources development -- Oregon -- Willamette River Valley8
- Water resources development -- Oregon6
- Water-supply -- Oregon6
- Water conservation -- Research -- Oregon5
- Water conservation -- Oregon4
- Water in agriculture4
- Irrigation -- Northwest, Pacific3
- Irrigation -- Oregon3
- Livestock -- Effect of drought on3
- Rangelands -- Water-supply3
- Water-supply, Agricultural3
- Irrigation -- Management2
- Irrigation scheduling2
- Irrigation scheduling -- Oregon2
- Irrigation water -- Conservation2
- Irrigation water -- Oregon -- Klamath Basin2
- Landscape gardening -- Water conservation2