Northwestern Washington Potato-Based Annual Cropping Systems LTARE Site
Key Objective
Identify and promote management practices that enhance soil health, carbon sequestration, and the environmental and economic sustainability of agricultural systems in northwestern Washington.
Cropping System and Region
Northwestern Washington Potato-Based Annual Cropping Systems
Location
WSU - Northwestern Washington Research and Extension Center in Mount Vernon, Washington
Climate and Soil Type
Annual high temperature: 59 F
Annual low temperature: 42 F
Average annual precipitation: 33 in
Primary soil type: Skagit silt loam
Established
2021
Area
16 acres with four primary treatments
Site Leaders
Gabriel LaHue - Soil Scientist, WSU
Deirdre Griffin LaHue - Soil Scientist, WSU
Chris Benedict - Weed Scientist, WSU
Collaborators
Chakradhar Mattupalli - Plant Pathologist, WSU
Louie Nottingham - Entomologist, WSU
Investigating reduced disturbance and increased organic matter additions
Treatment 1:
High disturbance and removal of crop residue in the typical crop rotation. Year 1: Potato - Fallow. Year 2: Spring Barley - Fallow. Year 3: Corn - Winter Wheat. Year 4: Winter Wheat - Fallow
- Baling and removing residue
- Full tillage between crops
Treatment 2:
High disturbance while leaving crop residue with annual cover crops in the typical crop rotation. Year 1: Potato - Cover Crop. Year 2: Spring Barley - Cover Crop. Year 3: Corn - Winter Wheat. Year 4: Winter Wheat - Cover Crop.
- Leave crop residue after grain crops
- Full tillage between crops
Treatment 3:
High disturbance while leaving crop residue with annual cover crops in the typical crop rotation. Year 1: Potato - Cover Crop. Year 2: Spring Barley - Cover Crop. Year 3: Corn - Winter Wheat. Year 4: Winter Wheat - Cover Crop.
- Leave crop residue after grain crops
- Both full and reduced tillage practices
- External soil amendments incorporated
Treatment 4:
Infrequent tillage with perennial cover crops and external soil amendments in a potato rotation. Year 1: Potato - Fallow. Year 2-4: Perennial Grass & Clover Mix
- Perennial cover crop residue left in the field
- Full tillage before and after potatoes
- External soil amendment incorporated