Subject
- Forest management -- California, Northern1
- Forest soils -- Carbon content -- California, Northern1
- Forest soils -- Fertilization -- California, Northern[remove]1
- Forest soils -- Nitrogen content -- California, Northern1
- Plants -- Effect of herbicides on -- California, Northern1
- Ponderosa pine -- Fertilizers -- California, Northern1
- Ponderosa pine -- Soils -- California, Northern1