Subject
- Biodiesel fuels -- Oregon -- Willamette River Valley1
- Biomass energy -- Law and Legislation -- Oregon -- Willamette River Valley -- Mathematical models1
- Cover crops -- Oregon1
- Energy crops industry -- Oregon -- Willamette River Valley -- Mathematical models1
- Insect-plant relationships--Oregon1
- Limnanthes--Oregon1
- Lotus corniculatus1
- Oil industries -- Subsidies -- Oregon -- Willamette River Valley -- Mathematical models1
- Scaptomyza--Host plants--Oregon1
- Weeds -- Control1