| Scientific Name | Notes | Rarity Ranks | Common Name |
|---|---|---|---|
| Blepharizonia plumosa | CNPS-EB: *A2 State CNPS: 1B.1 Global Rank: G1G2 CNDDB Rank: S1S2 | big tarplant | |
| Amaranthus californicus | CNPS-EB: B | Californian amaranth | |
| Arctostaphylos auriculata | CNPS-EB: *A2 State CNPS: 1B.3 Global Rank: G2 CNDDB Rank: S2 | Mount Diablo manzanita | |
| Arctostaphylos manzanita subsp. manzanita | CNPS-EB: A2 | common manzanita | |
| Calochortus pulchellus | CNPS-EB: *A2 State CNPS: 1B.2 Global Rank: G2 CNDDB Rank: S2 | Mount Diablo fairy-lantern | |
| Clarkia modesta | CNPS-EB: A2 | modest clarkia | |
| Collinsia sparsiflora var. unknown | CNPS-EB: C? | few-flowered blue-eyed Mary | |
| Fraxinus dipetala | CNPS-EB: B | California ash, flowering ash | |
| Galium andrewsii subsp. gatense | CNPS-EB: *A2 State CNPS: 4.2 Global Rank: G5T3 CNDDB Rank: S3 | phlox-leaf serpentine bedstraw, serpentine bedstraw | |
| Gilia tricolor subsp. diffusa | CNPS-EB: C | birds-eye gilia | |
| Helianthella castanea | CNPS-EB: *A2 State CNPS: 1B.2 Global Rank: G2 CNDDB Rank: S2 | Diablo helianthella | |
| Heterotheca sessiliflora subsp. bolanderi | (H. s. ssp. echioides is more | CNPS-EB: C | Bolander goldenaster |
| Juniperus californica | CNPS-EB: C | California juniper | |
| Koeleria macrantha | CNPS-EB: B-PV | june grass | |
| Lathyrus jepsonii var. californicus | CNPS-EB: B | buff pea | |
| Lepechinia calycina | CNPS-EB: C | pitcher sage | |
| Lupinus pachylobus | CNPS-EB: B | big pod lupine | |
| Melica californica | CNPS-EB: B-PV | California melic | |
| Navarretia pubescens | CNPS-EB: C | downy navarretia | |
| Phacelia breweri | CNPS-EB: B-PV | Brewer's phacelia | |
| Phoradendron leucarpum subsp. macrophyllum | (formerly P. serotinum subsp. macrophyllum, P. macrophyllum) | CNPS-EB: C | big leaf mistletoe |
| Pseudognaphalium biolettii | (formerly Gnaphalium bicolor) | CNPS-EB: A1 | Bioletti's cudweed |
| Quercus berberidifolia | CNPS-EB: C | scrub oak | |
| Quercus lobata | CNPS-EB: C | valley oak, roble | |
| Ranunculus canus var. canus | CNPS-EB: C | Sacramento Valley buttercup | |
| Rhus aromatica | (formerly R. trilobata) | CNPS-EB: C | skunk bush, skunkbrush, squawbush |
| Scutellaria tuberosa | CNPS-EB: C | Dannie's skullcap | |
| Stellaria nitens | CNPS-EB: B-PV | shining chickweed | |
| Stipa lepida | CNPS-EB: B-PV | foothill needlegrass | |
| Stipa pulchra | CNPS-EB: B-PV | purple needlegrass |