| Scientific Name | Notes | Rarity Ranks | Common Name |
|---|---|---|---|
| Alnus rubra | (A. rhombifolia is more common | CNPS-EB: A2 | red alder |
| Carex nebrascensis | CNPS-EB: B | Nebraska sedge | |
| Carex obnupta | CNPS-EB: B | slough sedge | |
| Amsinckia douglasiana | (historical-1938) | CNPS-EB: *A1x State CNPS: 4.2 Global Rank: G4 CNDDB Rank: S4 | Douglas' fiddleneck |