Plants ranked as California Rare Plant Rank 1B are rare, threatened, or endangered in California and elsewhere. The East Bay is home to numerous taxa ranked 1B:
Allium sharsmithiae (Sharsmith's onion)Amsinckia grandiflora (large-flowered fiddleneck)
Amsinckia lunaris (bent-flowered fiddleneck)
Arctostaphylos auriculata (Mount Diablo manzanita)
Arctostaphylos manzanita ssp. laevigata (Contra Costa manzanita)
Arctostaphylos pallida (pallid manzanita)
Astragalus tener var. tener (alkali milkvetch)
Atriplex cordulata var. cordulata
Atriplex depressa (brittlescale)
Atriplex minuscula (lesser saltscale)
Balsamorhiza macrolepis (big-scale balsamroot)
Blepharizonia plumosa (big tarplant)
Calochortus pulchellus (Mount Diablo fairy lantern)
Calystegia purpurata ssp. saxicola (coastal bluff morning-glory)
Campanula exigua (chaparral harebell)
Campanula sharsmithiae (Sharsmith's harebell)
Caulanthus lemmonii (Lemmon's jewelflower)
Centromadia parryi ssp. congdonii (Congdon's tarplant)
Chlorogalum pomeridianum var. minus (dwarf soaproot)
Chloropyron maritimum ssp. palustre (Point Reyes salty bird's-beak)
Chloropyron molle ssp. hispidum (hispid salty bird's-beak, hispid bird's-beak)
Chloropyron molle ssp. molle (soft salty bird's-beak, soft bird's-beak)
Chloropyron palmatum (palmate salty bird's-beak, palmate-bracted bird's-beak)
Chorizanthe cuspidata var. cuspidata (San Francisco Bay spineflower)
Chorizanthe robusta var. robusta (robust spineflower)
Cirsium andrewsii (Franciscan thistle)
Cirsium fontinale var. campylon (Mount Hamilton fountain thistle)
Clarkia franciscana (Presidio clarkia)
Cordylanthus nidularius (Mount Diablo bird's-beak)
Deinandra bacigalupii (Livermore tarplant)
Delphinium californicum ssp. interius (Hospital Canyon larkspur)
Delphinium recurvatum (recurved larkspur)
Dirca occidentalis (western leatherwood)
Eriastrum ertterae (Lime Ridge eriastrum)
Eriogonum luteolum var. caninum (Tiburon buckwheat)
Eriogonum nudum var. psychicola (Antioch Dunes buckwheat)
Eriogonum truncatum (Mount Diablo buckwheat)
Eryngium aristulatum var. hooveri (Hoover's button-celery)
Eryngium jepsonii
Eryngium racemosum (delta button-celery)
Eryngium spinosepalum
Erysimum capitatum var. angustatum (Contra Costa wallflower)
Eschscholzia rhombipetala (diamond-petaled California poppy)
Extriplex joaquinana (San Joaquin spearscale)
Fritillaria falcata (talus fritillary)
Fritillaria liliacea (fragrant fritillary)
Helianthella castanea (Diablo helianthella)
Hesperolinon breweri (Brewer’s dwarf flax)
Hibiscus lasiocarpos var. occidentalis (rose-mallow)
Hoita strobilina (Loma Prieta hoita)
Holocarpha macradenia (Santa Cruz tarplant)
Horkelia cuneata var. sericea (Kellogg's horkelia)
Isocoma arguta (Carquinez goldenbush)
Lasthenia conjugens (Contra Costa goldfields)
Lathyrus jepsonii var. jepsonii (delta tule pea)
Legenere limosa (legenere)
Leptosyne hamiltonii (Mount Hamilton coreopsis)
Lilaeopsis masonii (Mason's lilaeopsis)
Madia radiata (showy golden madia, showy madia)
Malacothamnus hallii (Hall's bush-mallow)
Meconella oregana (Oregon meconella)
Monolopia gracilens (woodland woollythreads, woodland monolopia)
Navarretia gowenii (Lime Ridge navarretia)
Navarretia nigelliformis ssp. radians (adobe navarretia, shining navarretia)
Navarretia prostrata (prostrate vernal pool navarretia)
Oenothera deltoides ssp. howellii (Antioch Dunes evening-primrose)
Phacelia phacelioides (Mount Diablo phacelia)
Plagiobothrys chorisianus var. chorisianus (Choris' popcornflower)
Plagiobothrys diffusus (San Francisco popcornflower)
Puccinellia simplex
Sanicula maritima (adobe sanicle)
Sanicula saxatilis (rock sanicle)
Spergularia macrotheca var. longistyla
Streptanthus albidus ssp. peramoenus (most beautiful jewel-flower)
Streptanthus hispidus (Mount Diablo jewelflower)
Suaeda californica (California seablite)
Symphyotrichum lentum (Suisun marsh aster)
Trifolium hydrophilum (saline clover)
Tropidocarpum capparideum (caper-fruited tropidocarpum)
