| Scientific Name | Notes | Rarity Ranks | Common Name |
|---|---|---|---|
| Calochortus pulchellus | CNPS-EB: *A2 State CNPS: 1B.2 Global Rank: G2 CNDDB Rank: S2 | Mount Diablo fairy-lantern | |
| Eriastrum abramsii | CNPS-EB: A2 | Abram's eriastrum | |
| Ericameria arborescens | CNPS-EB: B | golden-fleece | |
| Galium andrewsii subsp. gatense | CNPS-EB: *A2 State CNPS: 4.2 Global Rank: G5T3 CNDDB Rank: S3 | phlox-leaf serpentine bedstraw, serpentine bedstraw | |
| Hesperolinon breweri | CNPS-EB: *A2 State CNPS: 1B.2 Global Rank: G2 CNDDB Rank: S2 | Brewer's western flax | |
| Hesperolinon micranthum | CNPS-EB: A2 | small-flowered dwarf flax | |
| Pickeringia montana var. montana | CNPS-EB: C | chaparral pea | |
| Ribes malvaceum var. malvaceum | CNPS-EB: C | chaparral currant | |
| Blepharizonia plumosa | CNPS-EB: *A2 State CNPS: 1B.1 Global Rank: G1G2 CNDDB Rank: S1S2 | big tarplant | |
| Eriastrum pluriflorum subsp. pluriflorum | CNPS-EB: A1 | many-flowered eriastrum | |
| Forestiera pubescens | CNPS-EB: B | desert olive | |
| Fraxinus dipetala | CNPS-EB: B | California ash, flowering ash | |
| Helianthella castanea | CNPS-EB: *A2 State CNPS: 1B.2 Global Rank: G2 CNDDB Rank: S2 | Diablo helianthella | |
| Phoradendron leucarpum subsp. macrophyllum | (formerly P. serotinum subsp. macrophyllum, P. macrophyllum) | CNPS-EB: C | big leaf mistletoe |
| Quercus berberidifolia | CNPS-EB: C | scrub oak | |
| Quercus xjolonensis | CNPS-EB: A1? | blue oak x valley oak | |
| Stipa lepida | CNPS-EB: C | foothill needlegrass | |
| Stipa pulchra | CNPS-EB: C | purple needlegrass |