Abies concolor (White fir)
Abronia
    maritima (Red sand verbena)
    nana ssp. covillei (Coville's dwarf abronia)
    turbinata (White sand verbena)
    umbellata ssp. umbellata (Pink sand verbena)
    villosa var. aurita (Desert sand verbena)
    villosa var. villosa (Desert sand verbena)
Abutilon palmeri (Indian-mallow)
Acacia
    baileyana (Cootamundra wattle)*
    farnesiana var. farnesiana (Sweet acacia)**
    greggii (Catclaw acacia)
    longifolia (Golden wattle)**
Acalypha californica (California copperleaf)
Acamptopappus
    shockleyi (Shockley's goldenheads)
    sphaerocephalus (Goldenheads)
Acanthomintha
    ilicifolia (San Diego thornmint)
    obovata ssp. cordata (Heartleaf thornmint)
Acer
    glabrum (Mountain maple)
    macrophyllum (Big leaf maple)
    negundo var. californicum (Box elder)
Achillea millefolium (Yarrow)
Achnatherum
    coronatum (Giant stipa)
    diegoense (San Diego County needlegrass)
    hymenoides (Indian ricegrass)
    occidentale ssp. occidentale (Western needlegrass)
    parishii (Parish's needlegrass)
    speciosum (Desert needlegrass)
Achyrachaena mollis (Blow wives)
Achyronychia cooperi (Frostmat)
Acourtia microcephala (Perezia)
Acroptilon repens (Russian knapweed)*
Adenophyllum
    cooperi (Cooper's dyssodia)
    porophylloides (San Felipe dyssodia)
Adenostoma
    fasciculatum (Chamise)
    sparsifolium (Red shanks)
Adiantum
    aleuticum (Five-finger maidenhair fern)
    capillus-veneris (Maidenhair fern)
    jordanii (California maidenhair fern)
Adolphia californica (California adolphia)
Aegilops cylindrica (Jointed goatgrass)*
Aesculus
    californica (California buckeye)
    californica seed (California buckeye)
Agastache urticifolia (Giant hyssop)
Agave
    americana (Century plant)*
    deserti (Desert agave)
    shawii (Shaw's agave)
    utahensis (Utah agave)
Ageratina adenophora (Thoroughwort)*
Agropyron desertorum (Desert crested wheatgrass)*
Agoseris
    grandiflora (Mountain dandelion)
    retrorsa (Spearleaf mountain dandelion)
Agrostis
    idahoensis (Idaho bentgrass)
    pallens (Seashore bentgrass)
    viridis (Green bentgrass)*
Albizia lophantha (Plume acacia)*
Alisma plantago-aquatica (Water plantain)
Allionia incarnata (Windmills)
Allium
    amplectens (Narrow-leaved onion)
    atrorubens var. atrorubens (Wild onion)
    burlewii (Burlew's onion)
    campanulatum (Sierra onion)
    fimbriatum var. fimbriatum (Fringed onion)
    haematochiton (Red-skinned onion)
    howellii var. clokeyi (Mt. Pinos onion)
    lacunosum var. davisiae (Davis's pitted onion)
    monticola (San Bernardino mountain onion)
    parryi (Parry's fringed onion)
    peninsulare var. peninsulare (Peninsular onion)
    praecox (Early onion)
Allophyllum
    divaricatum (Purple false-gilia)
    gilioides ssp. gilioides (Dense false-gilia)
    gilioides ssp. violaceum (Violet false-gilia)
    glutinosum (Sticky false-gilia)
    integrifolium (White false-gilia)
Alnus rhombifolia (White alder)
Aloysia wrightii (Vera dulce)
Amaranthus
    albus (Pigweed amaranth)*
    blitoides (Prostrate amaranth)
    californicus (California amaranth)
    fimbriatus (Fringed amaranth)
    torreyi (Torrey's amaranth)
Amaryllis belladona (Naked ladies)**
Amblyopappus pusillus (Coastweed)
Ambrosia
    acanthicarpa (Annual bur-sage)
    chamissonis (Silver beach bur)
    chenopodiifolia (Goosefoot bur-sage)
    dumosa (Burrobush)
    eriocentra (Woolly bur-sage)
    psilostachya (Western ragweed)
    pumila (San Diego ambrosia)
Amelanchier utahensis (Utah serviceberry)
Ammannia coccinea (Red ammannia)
Amorpha
    californica var. californica (California false-indigo)
    fruticosa (Western false-indigo)
Amphipappus fremontii ssp. fremontii (Chaffbush)
Amsinckia
    menziesii var. intermedia (Common fiddleneck)
    menziesii var. menziesii (Small-flowered fiddleneck)
    spectabilis var. spectabilis (Seaside fiddleneck)
    tessellata var. tessellata (Checker fiddleneck)
Amsonia tomentosa (Woolly amsonia)
Anagallis arvensis (Scarlet pimpernel)*
Anemopsis californica (Yerba mansa)
Angelica lineariloba (Soda straw)
Anisocoma acaulis (Scalebud)
Antennaria
    dimorpha (Low pussytoes)
    rosea ssp. confinis (Rosy pussytoes)
Anthemis
    arvensis (Corn chamomile)*
    cotula (Mayweed)*
Anthriscus caucalis (Bur-chervil)*
Antirrhinum
    coulterianum (White snapdragon)
    filipes (Desert twining snapdragon)
    kelloggii (Twining snapdragon)
    multiflorum (Rose snapdragon)
    nuttallianum ssp. nuttallianum (Violet snapdragon)
Anulocaulis annulatus (Sticky ringstem)
Aphanes occidentalis (Western lady's mantle)
Apiastrum angustifolium (Wild celery)
Apium graveolens (Celery)*
Apocynum
    androsaemifolium (Spreading dogbane)
    cannabinum (Indian hemp)
Aptenia cordifolia (Baby sun rose)*
Aquilegia formosa (Columbine)
Arabidopsis thaliana (Mouse-ear cress)*
Arabis
    glabra var. glabra (Tower mustard)
    holboellii var. pinetorum (Pine rock-cress)
    parishii (Parish's rock-cress)
    perennans (Perennial rock-cress)
    platysperma var. platysperma (Broad-seeded rock-cress)
    pulchra var. gracilis (Slender beautiful rock-cress)
    pulchra var. pulchra (Beautiful rock-cress)
    rectissima var. rectissima (Bristly-leaved rock-cress)
    repanda var. repanda (Yosemite rock-cress)
    shockleyi (Shockley's rock-cress)
    sparsiflora var. arcuata (Arched elegant rock-cress)
    sparsiflora var. californica (Elegant rock-cress)
Aralia californica (California aralia)
Arbutus
    menziesii (Pacific madrone)
    menziesii fruit (Pacific madrone)
Arceuthobium
    abietinum (Fir dwarf mistletoe)
    campylopodum (Pine dwarf mistletoe)
Arctostaphylos
    catalinae (Santa Catalina Island manzanita)
    confertiflora (Santa Rosa Island manzanita)
    gabrielensis (San Gabriel manzanita)
    glandulosa ssp. crassifolia (Del Mar manzanita)
    glandulosa ssp. adamsii (Adams' manzanita)
    glandulosa ssp. glaucomollis (Eastwood manzanita)
    glandulosa ssp. mollis (Santa Monica Mountains manzanita)
    glandulosa ssp. mollis, fruit (Santa Monica Mountains manzanita)
    glandulosa ssp. zacaensis (Zaca Lake manzanita)
    glauca (Bigberry manzanita)
    insularis (Island manzanita)
    otayensis (Otay manzanita)
    parryana ssp. deserticum (Parry's manzanita)
    parryana ssp. parryana (Parry's manzanita)
    patula (Greenleaf manzanita)
    peninsularis (Peninsular manzanita)
    pringlei ssp. drupacea (Pink-bracted manzanita)
    pungens (Mexican manzanita)
    tomentosa (Woollyleaf manzanita)
Arenaria
    kingii (King's sandwort)
    macradenia var. macradenia (Desert sandwort)
    ursina (Bear Valley sandwort)
Argemone
    corymbosa (Mojave prickly poppy)
    munita (Chicalote)
Argyrochosma jonesii (Jones' cloak fern)
Aristida
    adscensionis (Three-awn)
    purpurea var. nealleyi (Nealley three-awn)
Armeria maritima ssp. californica (California sea-pink)
Arnica
    chamissonis ssp. foliosa (Meadow arnica)
    mollis (Soft arnica)
Artemisia
    californica (California sagebrush)
    douglasiana (Mugwort)
    dracunculus (Wild tarragon)
    ludoviciana ssp. incompta (Silver wormwood)
    nova (Black sagebrush)
    palmeri (Palmer's sagewort)
    rothrockii (Rothrock's sagebrush)
    tridentata ssp. parishii (Parish's sagebrush)
    tridentata ssp. tridentata (Basin sagebrush)
    tridentata ssp. vaseyana (Mountain sagebrush)
Arundo donax (Giant reed)*
Asclepias
    albicans (White-stemmed milkweed)
    californica (California milkweed)
    eriocarpa (Indian milkweed)
    erosa (Desert milkweed)
    fascicularis (Narrow-leaved milkweed)
    nyctaginifolia (Mojave milkweed)
    subulata (Rush milkweed)
    vestita (Woolly milkweed)
Asparagus asparagoides (African asparagus fern)*
Asphodelus fistulosus (Onionweed)*
Aspidotis californica (California lace fern)
Aster
    alpigenus var. andersonii (Alpine aster)
    ascendens (Long-leaved aster)
    bernardinus (San Bernardino aster)
    chilensis (Chile aster)
    greatae (Greata's aster)
    laneolatus ssp. hesperius (Western lanceleaf aster)
    occidentalis var. occidentalis (Western mountain aster)
    subulatus var. ligulatus (Slim aster)
Astragalus
    albens (Cushenbury milkvetch)
    bicristatus (Crested milkvetch)
    brauntonii (Braunton's rattleweed)
    cimae var. cimae (Cima milkvetch)
    coccineus (Scarlet milkvetch)
    curtipes (San Luis Obispo milkvetch)
    didymocarpus (Two-seeded milkvetch)
    douglasii var. douglasii (Jacumba milkvetch)
    douglasii var. parishii (Parish's jacumba milkvetch)
    filipes (Narrowpod locoweed)
    gambelianus (Gambel's dwarf milkvetch)
    gilmanii (Gilman's milkvetch)
    layneae (Layne's locoweed)
    lentiginosus var. borreganus (Borrego milkvetch)
    lentiginosus var. fremontii (Fremont's milkvetch)
    lentiginosus var. micans (Shining milkvetch)
    lentiginosus var. sierrae (Bear Valley milkvetch)
    lentiginosus var. variabilis (Varied milkvetch)
    leucolobus (Bear Valley woollypod)
    miguelensis (San Miguel milkvetch)
    minthorniae var. villosus (Minthorn's milkvetch)
    newberryi var. newberryi (Newberry's rattleweed)
    pachypus (Sheep's locoweed)
    palmeri (Palmer's milkvetch)
    panamintensis (Panamint milkvetch)
    pomonensis (Pomona locoweed)
    purshii var. lectulus (Pursh's milkvetch)
    purshii var. tinctus (Pursh's milkvetch)
    sabulonum (Gravel milkvetch)
    serenoi var. shockleyi (Naked milkvetch)
    tidestromii (Tidestrom's milkvetch)
    trichopodus var. lonchus (Coast locoweed)
    trichopodus var. phoxus (Santa Barbara milkvetch)
    whitneyi var. whitneyi (Whitney's locoweed)
Astrolepis cochisensis (Scaly cloak fern)
Athyrium filix-femina var. cyclosorum (Lady fern)
Athysanus pusillus (Dwarf athysanus)
Atrichoseris platyphylla (Gravel ghost)
Atriplex
    amnicola (Swamp saltbush)*
    californica (California saltbush)
    canescens ssp. canescens (Fourwing saltbush)
    confertifolia (Shadscale saltbush)
    glauca (Waxy saltbush)*
    hymenelytra (Desert-holly)
    lentiformis ssp. lentiformis (Quail bush)
    lentiformis ssp. torreyi (Torrey's saltbush)
    leucophylla (Beach saltbush)
    pacifica (Pacific saltbush)
    phyllostegia (Arrowscale)
    polycarpa (Cattle spinach)
    semibaccata (Australian saltbush)*
    triangularis (Arrowleaf saltbush)
    watsonii (Watson's saltbush)
Avena
    barbata (Slender oats)*
    fatua (Common wild oats)*
Ayenia compacta (Ayenia)
Baccharis
    douglasii (Salt marsh baccharis)
    emoryi (Emory baccharis)
    malibuensis (Malibu baccharis)
    pilularis (Coyote brush)
    plummerae ssp. plummerae (Plummer's baccharis)
    salicifolia (Mulefat)
    sarothroides (Broom baccharis)
    sergiloides (Desert baccharis)
    vanessae (Encinitas baccharis)
Bahia dissecta (Ragged-leaf bahia)
Baileya
    multiradiata var. multiradiata (Desert marigold)
    pauciradiata (Lax flower)
    pleniradiata (Woolly marigold)
Balsamorhiza deltoidea (Deltoid balsamroot)
Barbarea orthoceras (Winter cress)
Bassia hyssopifolia (Five-hook bassia)
Batis maritima (Saltwort)
Bebbia juncea var. aspera (Sweetbush)
Bellis perennis (English daisy)*
Berberis
    aquifolium var. repens (Creeping grape holly)
    fremontii (Fremont's barberry)
    nevinii (Nevin's barberry)
    pinnata ssp. pinnata (California barberry)
Bergerocactus emoryi (Golden-spined cereus)
Bernardia myricifolia (Bernardia)
Berula erecta (Water parsnip)
Beta vulgaris (Common beet)*
Bidens
    laevis (Smooth beggar-ticks)
    pilosa var. pilosa (Common beggar-ticks)*
Bituminaria bituminosa (Pitch trefoil)*
Blennosperma nanum var. nanum (Yellow carpet)
Bloomeria crocea (Golden stars)
Boerhavia
    coccinea (Red boerhavia)
    intermedia (Fivewing boerhavia)
    triquetra (Slender boerhavia)
    wrightii (Wright's boerhavia)
Boschniakia strobilacea (California groundcone)
Bouteloua
    aristidoides (Needle grama)
    eriopoda (Black grama)
    gracilis (Blue grama)
    trifida (Red grama)
Bowlesia incana (Bowlesia)
Boykinia
    occidentalis (Coast boykinia)
    rotundifolia (Round-leaved boykinia)
Brachypodium distachyon (Purple false-brome)*
Brandegea bigelovii (Brandegea)
Brassica
    fruticulosa (Mediterranean cabbage)*
    nigra (Black mustard)*
    rapa (Field mustard)*
    tournefortii (Asian mustard)*
Brickellia
    arguta (Spearleaf brickellbush)
    californica (California brickellbush)
    desertorum (Desert brickellbush)
    frutescens (Shrubby brickellbush)
    incana (Woolly brickellbush)
    microphylla (Little-leaved brickellbush)
    multiflora (Gum-leaved brickellbush)
    nevinii (Nevin's brickellbush)
    oblongifolia var. linifolia (Narrow-leaved brickellbush)
Brodiaea
    elegans (Harvest brodiaea)
    filifolia (Thread-leaved brodiaea)
    orcuttii (Orcutt's brodiaea)
    santarosae (Santa Rosa basalt brodiaea)   
    terrestris ssp. kernensis (Earth brodiaea)
Bromus
    carinatus var. carinatus (California brome)
    carinatus var. maritimus (Seaside brome)
    diandrus (Ripgut brome)*
    hordeaceus (Soft chess)*
    madritensis ssp. rubens (Red brome)*
    tectorum (Cheat grass)*
    trinii (Chilean chess)*
Buddleja utahensis (Panamint butterfly bush)
Bursera microphylla (Elephant tree)
Caesalpinia
    gilliesii (Yellow bird-of-paradise)*
    virgata (Hoffmanseggia)
Cakile maritima (Sea rocket)*
Calandrinia
    breweri (Brewer's red maids)
    ciliata (Red maids)
    maritima (Seaside red maids)
Calliandra
    californica (Baja fairy duster)**
    eriophylla (Pink fairy duster)
Callistemon sp. (Bottlebrush)**
Callitriche heterophylla var. bolanderi (Water-starwort)
Calocedrus decurrens (Incense-cedar)
Calochortus
    albus (Fairy lantern)
    catalinae (Catalina mariposa lily)
    clavatus ssp. pallidus (Yellow mariposa lily)
    clavatus var. gracilis (Slender mariposa lily)
    concolor (Golden bowl mariposa lily)
    dunnii (Dunn's mariposa lily)
    flexuosus (Winding mariposa lily)
    invenustus (Plain mariposa lily)
    invenustus (blue form) (Plain mariposa lily)
    kennedyi var. kennedyi (Red mariposa lily)
    kennedyi var. munzii (Desert mariposa lily)
    palmeri var. munzii (Munz's mariposa lily)
    palmeri var. palmeri (Palmer's mariposa lily)
    plummerae (Plummer's mariposa lily)
    splendens (Splendid mariposa lily)
    striatus (Alkali mariposa lily)
    venustus (Butterfly mariposa lily)
    weedii var. weedii (Weed's mariposa lily)
Calycanthus occidentalis (Spicebush)*
Calycoseris
    parryi (Yellow tackstem)
    wrightii (White tackstem)
Calyptridium
    monandrum (Sand cress)
    monospermum (Pussypaws)
    parryi var. parryi (Parry's pussypaws)
Calystegia
    collina ssp. venusta (Coast range bindweed)
    macrostegia ssp. amplissima (Southern island morning glory)
    macrostegia ssp. arida (Southern California morning glory)
    macrostegia ssp. cyclostegia (Coast morning glory)
    macrostegia ssp. intermedia (South coast morning glory)
    macrostegia ssp. macrostegia (Northern island morning glory)
    macrostegia ssp. tenuifolia (San Diego morning glory)
    malacophylla ssp. pedicellata (Jepson's morning glory)
    occidentalis ssp. fulcrata (Western morning glory)
    soldanella (Beach morning glory)
Camissonia
    bistorta (Sun cup)
    boothii ssp. condensata (Booth's shredding sun cup)
    boothii ssp. decorticans (Shredding evening primrose)
    boothii ssp. desertorum (Desert sun cup)
    boothii ssp. intermedia (Booth's intermediate sun cup)
    brevipes ssp. brevipes (Yellow cup)
    californica (Mustard evening primrose)
    campestris ssp. campestris (Mojave sun cup)
    cardiophyla ssp. cardiophylla (Heartleaf sun cup)
    cheiranthifolia ssp. cheiranthifolia (Channel Islands beach primrose)
    cheiranthifolia ssp. suffruticosa (Beach primrose)
    claviformis ssp. claviformis (Mojave brown-eyed primrose)
    claviformis ssp. funerea (Death Valley brown-eyed primrose)
    claviformis ssp. lancifolia (Lanceleaf browneyes)
    claviformis ssp. peirsonii (Peirson's brown-eyed primrose)
    confusa (San Bernardino sun cup)
    hirtella (Hairy sun cup)
    intermedia (Intermediate sun cup)
    micrantha (Small evening primrose)
    pallida ssp. pallida (Pale primrose)
    pterosperma (Wingfruit sun cup)
    pusilla (Little wiry sun cup)
    refracta (Narrow-leaf suncup)
    strigulosa (Strigose sun cup)
    walkeri ssp. tortilis (Walker's sun cup)
Canbya candida (Pygmy poppy)
Capsella bursa-pastoris (Shepherd's purse)*
Cardamine
    californica var. californica (Milkmaids)
    oligosperma (Bitter cress)
Cardionema ramosissimum (Sandmat)
Carduus pycnocephalus (Italian thistle)*
Carex
    alma (Sturdy sedge)
    densa (Dense sedge)
    fracta (Fragile-sheathed sedge)
    multicaulis (Forest sedge)
    praegracilis (Clustered field sedge)
    senta (Swamp sedge)
    spissa (San Diego sedge)
    subfusca (Rusty slender sedge)
    triquetra (Triangular-fruit sedge)
Carnegiea gigantea (Giant saguaro)
Carpenteria californica (Bush anenome)**
Carpobrotus
    chilensis (Sea fig)*
    edulis (Hottentot fig)*
Carthamus tinctorius (Safflower)*
Castela emoryi (Crucifixion thorn)
Castilleja
    affinis ssp. affinis (Indian paintbrush)
    angustifolia (Desert indian paintbrush)
    applegatei ssp. martinii (Martin's paintbrush)
    cinerea (Ashy-gray paintbrush)
    densiflora (Dense-flowered owl's clover)
    exserta ssp. exserta (Purple owl's clover)
    foliolosa (Woolly indian paintbrush)
    lanata ssp. hololeuca (Island paintbrush)
    lasiorhyncha (San Bernardino Mountains owl's clover)
    linariifolia (Desert paintbrush)
    miniata ssp. miniata (Great red paintbrush)
    minor ssp. spiralis (Lesser indian paintbrush)
    mollis (Soft-leaved indian paintbrush)
    nana (Dwarf alpine paintbrush)
    plagiotoma (Yellow paintbrush)
    pruinosa (Frosted indian paintbrush)
Caulanthus
    amplexicaulis var. amplexicaulis (Clasping-leaved caulanthus)
    cooperi (Cooper's jewelflower)
    coulteri var. coulteri (Coulter's jewelflower)
    crassicaulis var. crassicaulis (Thickstem wildcabbage)
    hallii (Hall's caulanthus)
    heterophyllus var. heterophyllus (Slender-pod jewelflower)
    inflatus (Desert candle)
    major var. major (Slender wildcabbage)
    simulans (Payson's jewelflower)
Ceanothus
    arboreus (Island ceanothus)
    cordulatus (Mountain whitethorn)
    crassifolius (Hoaryleaf ceanothus)
    cuneatus var. cuneatus (Buckbrush)
    cyaneus (Lakeside ceanothus)
    greggii var. perplexans (Cupleaf ceanothus)
    greggii var. vestitus (Mojave ceanothus)
    integerrimus (Deerbrush)
    leucodermis (Chaparral whitethorn)
    megacarpus var. megacarpus (Bigpod ceanothus)
    oliganthus var. oliganthus (Hairy ceanothus)
    oliganthus var. sorediatus (Jim brush)
    palmeri (Palmer's ceanothus)
    spinosus (Greenbark ceanothus)
    tomentosus [var. olivaceous] (Woollyleaf ceanothus)
    verrucosus (Wartstem ceanothus)
Celtis reticulata (Western hackberry)
Centaurea
    maculosa (Spotted knapweed)*
    melitensis (Tocalote)*
    solstitialis (Yellow star thistle)*
Centaurium venustum (Canchalagua)
Centranthus ruber (Red valerian)*
Centrostegia thurberi (Thurber's spineflower)
Centunculus minimus (Common chaffweed)
Cerastium
    fontanum ssp. vulgare (Perennial chickweed)*
    glomeratum (Mouse-ear chickweed)*
Cercidium
    floridum ssp. floridum (Palo verde)
    floridum ssp. floridum fruit (Palo verde)
    microphyllum (Littleleaf palo verde)
Cercis occidentalis (Western redbud)
Cercocarpus
    betuloides var. betuloides (Birch-leaf mountain mahogany)
    betuloides var. blancheae (Island mountain mahogany)
    intricatus (Little-leaved mountain mahogany)
    ledifolius var. intermontanus (Curl-leaf mountain mahogany)
    minutiflorus (San Diego mountain mahogany)
    traskiae (Catalina Island mountain mahogany)
Chaenactis
    artemisiifolia (White pincushion)
    carphoclinia var. carphoclinia (Pebble pincushion)
    douglasii var. douglasii (Dusty maidens)
    fremontii (Fremont's pincushion)
    glabriuscula var. glabriuscula (Yellow pincushion)
    macrantha (Large-flowered pincushion)
    santolinoides (Santolina pincushion)
    stevioides (Esteve pincushion)
    xantiana (Xantus pincushion)
Chaetadelpha wheeleri (Dune broom)
Chaetopappa ericoides (Rose heath)
Chamaebatia australis (Southern mountain misery)
Chamaebatiaria millefolium (Desert sweet)
Chamaesyce
    albomarginata (Rattlesnakeweed)
    arizonica (Arizona spurge)
    melanadenia (Red-gland spurge)
    micromera (Sonoran spurge)
    ocellata ssp. arenicola (Dune spurge)
    parryi (Parry's spurge)
    polycarpa (Small-seeded spurge)
    prostrata (Prostrate spurge)*
    serpyllifolia ssp. serpyllifolia (Thyme-leaved spurge)
    setiloba (Yuma spurge)
Chamomilla suaveolens (Pineapple weed)*
Chasmanthe floribunda (South African cornflag)*
Cheilanthes
    clevelandii (Cleveland's lipfern)
    covillei (Coville's lipfern)
    feei (Slender lipfern)
    newberryi (Cotton fern)
    parryi (Parry's lipfern)
    viscida (Viscid lipfern)
Chenopodium
    album (Lamb's quarters)*
    ambrosioides (Mexican-tea)*
    atrovirens (Forest goosefoot)
    botrys (Jerusalem-oak goosefoot)*
    californicum (California goosefoot)
    fremontii (Fremont's goosefoot)
    hians (Gaping goosefoot)
    macrospermum var. halophilum (Coast goosefoot)*
    murale (Nettleleaf goosefoot)*
    pratericola (Meadow goosefoot)
Chilopsis linearis ssp. arcuata (Desert willow)
Chimaphila menziesii (Little prince's pine)
Chloracantha spinosa var. spinosa (Spiny aster)
Chlorogalum
    parviflorum (Small-flowered soap plant)
    pomeridianum var. pomeridianum (Soap plant)
Chondrilla juncea (Skeleton weed)*
Chorizanthe
    brevicornu var. brevicornu (Brittle spineflower)
    fimbriata var. fimbriata (Fringed spineflower)
    fimbriata var. laciniata (Lace-fringed spineflower)
    parryi var. fernandina (San Fernando Valley spineflower)
    procumbens (Prostrate spineflower)
    rigida (Rigid spineflower)
    spinosa (Mojave spineflower)
    staticoides (Turkish rugging)
    watsonii (Five-tooth spineflower)
    xanti var. leucotheca (Riverside spineflower)
Chrysanthemum coronarium (Garland chrysanthemum)*
Chrysolepis
    sempervirens (Bush chinquapin)
    sempervirens seed pod (Bush chinquapin)
Chrysothamnus
    nauseosus ssp. bernardinus, see Ericameria nauseosa var. bernardina
    nauseosus ssp. ceruminosus, see Ericameria nauseosa var. ceruminosa
    nauseosus ssp. consimilis (Threadleaf rubber rabbitbrush)
    nauseosus ssp. hololeucus, see Ericameria nauseosa var. hololeuca
    nauseosus ssp. mohavensis (Mojave rubber rabbitbrush)
    paniculatus (Black-banded rabbitbrush)
    parryi ssp. asper (Parry's rabbitbrush)
    viscidiflorus ssp. viscidiflorus (Sticky-leaved rabbitbrush)
Cichorium intybus (Chicory)*
Cirsium
    neomexicanum (Desert thistle)
    nidulum (Red thistle)
    occidentale var. californicum (California thistle)
    occidentale var. occidentale (Cobweb thistle)
    occidentale var. venustum (Venus thistle)
    scariosum (Elk thistle)
    vulgare (Bull thistle)*
Cistus
    creticus (Pink rock-rose)*
    ladanifer var. albiflorus (White-flowered rock-rose)*
    ladanifer var. maculatus (Crimson spot rock-rose)*
    Xpurpureus (Orchid rock-rose)*
Clarkia
    bottae (Farewell-to-spring)
    cylindrica ssp. cylindrica (Speckled clarkia)
    dudleyana (Dudley's clarkia)
    epilobioides (Canyon clarkia)
    purpurea ssp. quadrivulnera (Purple clarkia)
    rhomboidea (Diamond-petalled clarkia)
    similis (Ramona clarkia)
    unguiculata (Elegant clarkia)
    xantiana ssp. xantiana (Gunsight fairyfan)
Claytonia
    exigua ssp. exigua (Little spring beauty)
    parviflora ssp. parviflora (Narrow-leaf miner's lettuce)
    parviflora ssp. viridis (Green miner's lettuce)
    perfoliata ssp. mexicana (Southern miner's lettuce)
    perfoliata ssp. perfoliata (Miners' lettuce)
Clematis
    lasiantha (Pipestems)
    lasiantha achenes (Pipestems)
    ligusticifolia (Virgin's bower)
    pauciflora (Ropevine)
Cleome sparsifolia (Naked cleome)
Cleomella obtusifolia (Mojave stinkweed)
Cneoridium dumosum (Bushrue)
Cnicus benedictus (Blessed thistle)*
Coleogyne ramosissima (Blackbrush)
Collinsia
    callosa (Desert collinsia)
    childii (Child's collinsia)
    concolor (Southern chinese houses)
    heterophylla (Chinese houses)
    parryi (Parry's collinsia)
    parviflora (Small-flowered collinsia)
    torreyi var. wrightii (Wright's collinsia)
Collomia
    grandiflora (Large-flowered collomia)
    linearis (Slenderleaf collomia)
Colutea arborescens (Bladder senna)*
Comarostaphylis
    diversifolia ssp. diversifolia (Summer-holly)
    diversifolia ssp. planifolia (Summer-holly)
Commelina benghalensis (Bengal dayflower)**
Conium maculatum (Poison hemlock)*
Convolvulus
    arvensis (Bindweed)*
    simulans (Small-flowered morning glory)
Conyza
    bonariensis (Small horseweed)*
    canadensis (Tall horseweed)
    coulteri (Coulter's horseweed)
    floribunda (Asthmaweed)*
Corallorhiza maculata (Spotted coralroot)
Cordylanthus
    maritimus ssp. maritimus (Salt marsh bird's beak)
    nevinii (Nevin's bird's beak)
    orcuttianus (Orcutt's bird's beak)
    parviflorus (Purple bird's beak)
    rigidus ssp. setigerus (Bristly bird's beak)
Coreopsis
    bigelovii (Bigelow's coreopsis)
    californica var. californica (California tickseed)
    gigantea (Giant coreopsis)
    maritima (Sea dahlia)
Cornus
    nuttallii (Mountain dogwood)
    sericea ssp. sericea (American dogwood)
Coronopus didymus (Wart cress)*
Cortaderia selloana (Pampas grass)*
Cosmos bipinnatus (Mexican aster)*
Cotula
    australis (Australian brass-buttons)*
    coronopifolia (Brass-buttons)*
Crassula
    aquatica (Water pygmy weed)
    argentea (Jade plant)**
    connata (Pygmy weed)
Crepis
    acuminata (Tall hawksbeard)
    nana (Dwarf hawksbeard)
    occidentalis (Western hawksbeard)
Cressa truxillensis (Alkali weed)
Crossosoma
    bigelovii (Rock crossosoma)
    californicum (Catalina crossosoma)
Croton
    californicus (male flowers) (California croton)
    californicus (female flowers) (California croton)
    wigginsii (Wiggins's croton)
Cryptantha
    angustifolia (Narrow-leaved forget-me-not)
    barbigera (Bearded cryptantha)
    cinerea var. abortiva (Bownut cryptantha)
    circumscissa (Cushion cryptantha)
    clevelandii (Cleveland's popcorn flower)
    confertiflora (Yellow cryptantha)
    costata (Ribbed forget-me-not)
    decipiens (Gravel cryptantha)
    dumetorum (Bushloving cryptantha)
    echinella (Prickly popcorn flower)
    flavoculata (Roughseed cryptantha)
    holoptera (Winged cryptantha)
    intermedia (Large-flowered popcorn flower)
    maritima (Guadalupe cryptantha)
    micrantha (Redroot cryptantha)
    microstachys (Tejon cryptantha)
    mohavensis (Mojave cryptantha)
    muricata (Prickly cryptantha)
    pterocarya (Wingnut cryptantha)
    recurvata (Curvenut cryptantha)
    simulans (Pinewoods cryptantha)
    tumulosa (New York Mountains cryptantha)
    utahensis (Scented forget-me-not)
    virginensis (Virgin River cryptantha)
Cucurbita
    foetidissima (Calabazilla)
    foetidissima fruit (Calabazilla)
    palmata (Coyote melon)
Cupressus
    arizonica ssp. arizonica (Cuyamaca cypress)
    forbesii (Tecate cypress)
Cuscuta
    californica var. breviflora (Short-flowered California dodder)
    californica var. californica (California dodder)
    californica var. papillosa (Papillate dodder)
    denticulata (Desert dodder)
    pentagona (Western field dodder)
    salina var. major (Salt marsh dodder)
    subinclusa (Canyon dodder)
Cusickiella douglasii (Alkali draba)
Cycladenia humilis var. venusta (Showy cycladenia)
Cylindropuntia
    californica var. parkeri (Cane cholla)
    ganderi (Gander's cholla)
Cymopterus
    gilmanii (Gilman's cymopterus)
    multinervatus (Arizona springparsley)
Cynara cardunculus (Cardoon)*
Cynodon dactylon (Bermuda grass)*
Cyperus
    eragrostis (Tall flat sedge)
    involucratus (Umbrella plant)*
Cystopteris fragilis (Brittle fern)
Cytisus striatus (Portuguese broom)*
Dalea
    mollis (Silky dalea)
    mollissima (Downy dalea)
Datisca glomerata (Durango root)
Datura
    discolor (Desert thornapple)
    wrightii (Sacred datura)
Daucus pusillus (American wild carrot)
Dedeckera eurekensis (July gold)
Delairea odorata (Cape-ivy)*
Delphinium
    cardinale (Scarlet larkspur)
    parishii ssp. pallidum (Pale larkspur)
    parishii ssp. parishii (Desert larkspur)
    parryi ssp. parryi (Blue larkspur)
    patens ssp. hepaticoideum (Spreading larkspur)
Dendromecon
    harfordii (Channel Island tree poppy)
    rigida (Bush poppy)
Deschampsia elongata (Slender hairgrass)
Descurainia
    californica (Sierra tansy mustard)
    incana (Mountain tansy mustard)
    pinnata (Tansy mustard)
Dicentra
    chrysantha (Golden ear drops)
    ochroleuca (Bleeding hearts)
Dichelostemma capitatum ssp. capitatum (Blue dicks)
Dichondra occidentalis (Western dichondra)
Dicoria canescens (Desert dicoria)
Digitalis purpurea (Foxglove)*
Distichlis spicata (Salt grass)
Ditaxis
    lanceolata (Narrow-leaf ditaxis)
    neomexicana (New mexico ditaxis)
Dithyrea californica (Spectacle pod)
Dodecatheon
    alpinum (Alpine shooting star)
    clevelandii ssp. clevelandii (Shooting star)
    clevelandii ssp. insulare (Island shooting star)
    hendersonii (Foothill shooting star)
    redolens (Fragrant shooting star)
Downingia
    bella (Spotted downingia)
    cuspidata (Toothed calicoflower)
Draba
    corrugata var. corrugata (Southern California draba)
    cuneifolia (California draba)
    verna (Spring draba)
Dryopteris arguta (Coastal wood fern)
Duchesnea indica (Mock-strawberry)*
Dudleya
    abramsii ssp. affinis (San Bernardino Mountains dudleya)
    arizonica (Arizona chalk dudleya)
    attenuata ssp. orcuttii (Orcutt's dudleya)
    caespitosa (Sand-lettuce)
    candelabrum (Candleholder dudleya)
    cymosa ssp. crebifolia (San Gabriel River dudleya)
    cymosa ssp. marcescens (Santa Monica Mountains dudleya)
    cymosa ssp. pumila (Low canyon dudleya)
    densiflora (San Gabriel Mountains dudleya)
    edulis (Ladies' fingers)
    greenei (Greene's dudleya)
    hassei (Hasse's dudleya)
    lanceolata (Lanceleaf dudleya)
    multicaulis (Many-stemmed dudleya)
    pulverulenta ssp. pulverulenta (Chalk dudleya)
    saxosa ssp. aloides (Rock dudleya)
    traskiae (Santa Barbara Island dudleya)
    variegata (Variegated dudleya)
    viscida (Sticky dudleya)
Echinocactus polycephalus var. polycephalus (Cottontop cactus)
Echinocereus
    engelmannii (Engelmann's hedgehog cactus)
    triglochidiatus (Mojave mound cactus)
Echinodorus berteroi (Burhead)
Echium fastuosum (Pride of madeira)**
Eleocharis
    acicularis var. acicularis (Needle spikerush)
    macrostachya (Common spikerush)
    montevidensis (Sand spikerush)
Elymus
    elymoides ssp. brevifolius (Short-leaved squirreltail)
    elymoides ssp. californicus (California squirreltail)
    glaucus ssp. glaucus (Blue wildrye)
    glaucus ssp. jepsonii (Jepson's blue wildrye)
Elytrigia
    intermedia ssp. intermedia (Intermediate wheatgrass)*
    pontica ssp. pontica (Tall wheatgrass)*
Emex spinosa (Devil's thorn)*
Emmenanthe penduliflora var. penduliflora (Whispering bells)
Encelia
    actoni (Acton encelia)
    californica (Bush sunflower)
    farinosa (Brittlebush)
    frutescens (Rayless encelia)
    virginensis (Green encelia)
Enceliopsis
    covillei (Panamint daisy)
    nudicaulis (Sunray)
Ephedra
    californica (California ephedra)
    nevadensis (Nevada ephedra)
    viridis (Green ephedra)
Epilobium
    angustifolium ssp. circumvagum (Fireweed)
    brachycarpum (Field willowherb)
    canum ssp. canum (Hoary fuchsia)
    canum ssp. latifolium (California fuchsia)
    ciliatum ssp. ciliatum (Willow-herb)
    ciliatum ssp. glandulosum (Glandular willow-herb)
    densiflorum (Spike primrose)
    glaberrimum ssp. glaberrimum (Smooth willow-herb)
    oregonense (Oregon willow-herb)
    pygmaeum (Smooth boisduvalia)
Epipactis gigantea (Stream orchid)
Equisetum
    arvense (Common horsetail)
    hyemale ssp. affine (Common scouring rush)
    laevigatum (Smooth scouring rush)
    telmateia ssp. braunii (Giant horsetail)
Eremalche
    exilis (White mallow)
    rotundifolia (Desert fivespot)
Eremocarpus setigerus (Doveweed)
Eriastrum
    densifolium ssp. austromontanum (Southern mountain woolstar)
    densifolium ssp. mohavense (Mojave woolstar)
    densifolium ssp. sanctorum (Santa Ana River woolstar)
    diffusum (Miniature woolstar)
    eremicum ssp. eremicum (Desert woolstar)
    harwoodii (Harwood's woolstar)
    sapphirinum (Sapphire woolstar)
    sparsiflorum (Few-flowered woolstar)
    wilcoxii (Wilcox's woolstar)
Ericameria
    brachylepis (Boundary goldenbush)
    cooperi var. cooperi (Cooper's goldenbush)
    cuneata var. cuneata (Rock goldenbush)
    cuneata var. spathulata (Wide-leaved rock goldenbush)
    ericoides (Mock heather)
    laricifolia (Turpentine bush)
    linearifolia (Interior goldenbush)
    nana (Dwarf goldenbush)
    nauseosa var. bernardina (San Bernardino rubber rabbitbrush)
    nauseosa var. ceruminosa (Sharp-bracted rubber rabbitbrush)
    nauseosa var. hololeuca (Ghostly rubber rabbitbrush)
    palmeri var. pachylepis (Palmer's goldenbush)
    parishii var. parishii (Parish's goldenbush)
    pinifolia (Pine goldenbush)
Erigeron
    aphanactis var. congestus (Rayless fleabane)
    breweri var. breweri (Brewer's fleabane)
    breweri var. covillei (Coville's fleabane)
    breweri var. jacinteus (San Jacinto Mountains fleabane)
    compositus (Cutleaf daisy)
    concinnus (Navajo fleabane)
    divergens (Spreading fleabane)
    foliosus var. foliosus (Leafy daisy)
    glaucus (Seaside daisy)
    parishii (Parish's fleabane)
Eriodictyon
    crassifolium (Thickleaf yerba santa)
    traskiae (Trask's yerba santa)
    trichocalyx var. lanatum (Hairy yerba santa)
    trichocalyx var. trichocalyx (Smoothleaf yerba santa)
Eriogonum
    angulosum (Angled-stem buckwheat)
    apiculatum (San Jacinto buckwheat)
    arborescens (Santa Cruz Island buckwheat)
    cinereum (Ashyleaf buckwheat)
    contiguum (Reveal's buckwheat)
    crocatum (Conejo buckwheat )
    davidsonii (Davidson's buckwheat)
    deflexum (Flatcrown buckwheat)
    deserticola (Dune buckwheat)
    elongatum var. elongatum (Longstem buckwheat)
    eremicola (Wildrose Canyon buckwheat)
    fasciculatum var. fasciculatum (California buckwheat)
    fasciculatum var. flavoviride (East Mojave buckwheat)
    fasciculatum var. foliolosum (Leafy buckwheat)
    fasciculatum var. polifolium (Desert wild buckwheat)
    giganteum (St. Catherine's lace)
    gilmanii (Gilman's buckwheat)
    gracile var. gracile (Slender buckwheat)
    grande var. grande (Island buckwheat)
    grande var. rubescens (Red-flowered buckwheat)
    heermannii var. argense (Heermann's buckwheat)
    heermannii var. floccosum (Heermann's buckwheat)
    inflatum (Desert trumpet)
    kennedyi var. alpigenum (Southern alpine buckwheat)
    kennedyi var. austromontanum (Southern mountain buckwheat)
    kennedyi var. kennedyi (Kennedy's buckwheat)
    maculatum (Spotted buckwheat)
    microthecum var. johnstonii (Johnston's buckwheat)
    molestum (Pineland buckwheat)
    nidularium (Birdnest buckwheat)
    nudum var. pauciflorum (Few-flowered naked buckwheat)
    nudum var. westonii (Weston's buckwheat)
    ovalifolium var. ovalifolium (Oval-leaved buckwheat)
    ovalifolium var. vineum (Cushenbury buckwheat)
    palmerianum (Palmer's buckwheat)
    panamintense (Panamint buckwheat)
    parishii (Parish's buckwheat)
    parvifolium (Seacliff buckwheat)
    plumatella (Flat-topped buckwheat)
    pusillum (Yellow turban)
    reniforme (Kidney-leaved buckwheat)
    rixfordii (Rixford's buckwheat)
    saxatile (Rock buckwheat)
    thomasii (Thomas' buckwheat)
    thornei (Thorne's buckwheat)
    trichopes var. trichopes (Little trumpet)
    umbellatum var. minus (Alpine sulpher-flowered buckwheat)
    umbellatum var. munzii (Munz's buckwheat)
    umbellatum var. nevadense (Nevada buckwheat)
    umbellatum var. subaridum (Sulpher-flowered buckwheat)
    umbellatum var. versicolor (Varicolored buckwheat)
    wrightii var. membranaceum (Wright's buckwheat)
    wrightii var. nodosum (Knotty buckwheat)
    wrightii var.. subscaposum (Wright's buckwheat)
    wrightii var. wrightii (Wright's buckwheat)
Erioneuron pulchellum (Fluffgrass)
Eriophyllum
    ambiguum (Yellow-frocks)
    confertiflorum var. confertiflorum (Golden yarrow)
    lanatum var. obovatum (Woolly sunflower)
    lanosum (White easter bonnets)
    nevinii (Nevin's woolly sunflower)
    pringlei (Pringle eriophyllum)
    wallacei (Woolly daisy)
Erodium
    botrys (Long-beaked storksbill)*
    brachycarpum (Short-fruited filaree)*
    cicutarium (Redstem filaree)*
    macrophyllum (White-flowered filaree)
    moschatum (Whitestem filaree)*
    texanum (Desert heron's bill)
Eryngium aristulatum var. parishii (San Diego button-celery)
Erysimum
    capitatum ssp. capitatum (Western wallflower)
    insulare ssp. insulare (Island wallflower)
Eschscholzia
    caespitosa (Collarless California poppy)
    californica (California poppy)
    glyptosperma (Desert gold poppy)
    minutiflora (Little gold poppy)
    parishii (Parish's poppy)
Escobaria
    vivipara var. alversonii (Alverson's spinystar)
    vivipara var. deserti (Desert spinystar)
    vivipara var. rosea (Rosy spinystar)
Eucalyptus globulus (Blue gum)*
Eucnide urens (Desert rocknettle)
Eucrypta
    chrysanthemifolia var. chrysanthemifolia (Common eucrypta)
    micrantha (Small-flowered eucrypta)
Euonymus occidentalis var. parishii (Burning bush)
Euphorbia
    characias (Bush spurge)*
    crenulata (Chinese caps)
    eriantha (Beetle spurge)
    incisa (Mojave spurge)
    lathyris (Caper spurge)*
    misera (Cliff spurge)
    palmeri (Woodland spurge)
    peplus (