Abies concolor (White fir)
Abronia
    maritima (Red sand verbena)
    nana var. covillei (Coville's dwarf abronia)
    turbinata (White sand verbena)
    umbellata var. umbellata (Pink sand verbena)
    villosa var. aurita (Desert sand verbena)
    villosa var. villosa (Desert sand verbena)
Abutilon palmeri (Indian-mallow)
Acacia
    baileyana (Cootamundra wattle)*
    greggii, see Senegalia greggii
    longifolia (Golden wattle)*
Acalypha californica (California copperleaf)
Acamptopappus
    shockleyi (Shockley's goldenheads)
    sphaerocephalus var. sphaerocephalus (Goldenheads)
Acanthomintha
    ilicifolia (San Diego thornmint)
    obovata ssp. cordata (Heartleaf thornmint)
Acanthoscyphus
    parishii var. cienegensis (Cienega seca oxytheca)
    parishii var. goodmaniae (Cushenbury oxytheca)
    parishii var. parishii (Parish's oxytheca)
Acer
    glabrum var. diffusum (Mountain maple)
    macrophyllum (Big-leaf maple)
    negundo (Box elder)
Achillea millefolium (Yarrow)
Achnatherum
    aridum. see Stipa arida
    coronatum, see Stipa coronata
    diegoense, see Stipa diegoensis
    hymenoides, see Stipa hymenoides
    occidentale var. occidentale, see Stipa occidentalis var. occidentalis
    parishii, see Stipa parishii var. parishii
    speciosum, see Stipa speciosa
Achyrachaena mollis (Blow wives)
Achyronychia cooperi (Frostmat)
Acmispon
    americanus var. americanus (Spanish clover)
    argophyllus var. adsurgens (San Clemente Island bird's-foot trefoil)
    argophyllus var. argophyllus (Silver lotus)
    argophyllus var. niveus (Santa Cruz Island bird's-foot trefoil)
    argyraeus var. argyraeus (Canyon bird's-foot trefoil)
    argyraeus var. multicaulis (Scrub lotus)
    brachycarpus (Hill lotus)
    dendroideus var. dendroideus (Island deerweed)
    dendroideus var. veatchii (San Miguel Island deerweed)
    denticulatus (River bar bird's-foot trefoil)
    glaber var. brevialatus (Short-winged deerweed)
    glaber var. glaber (Common deerweed)
    grandiflorus var. grandiflorus (Large-flowered lotus)
    haydonii (Pygmy lotus)
    heermannii var. heermannii (Heermann's lotus)
    maritimus var. brevivexillus (Short-bannered coastal lotus)
    maritimus var. maritimus (Coastal lotus)
    micranthus (Small-flowered lotus)
    nevadensis var. davidsonii (Davidson's lotus)
    nevadensis var. nevadensis (Sierra Nevada lotus)
    procumbens var. procumbens (Silky deerweed)
    rigidus (Desert rock pea)
    strigosus (Strigose lotus)
    wrangelianus (California lotus)
Acourtia microcephala (Perezia)
Acroptilon repens (Russian knapweed)*
Actaea rubra (Red baneberry)
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 var. shawii (Shaw's agave)
    utahensis (Utah agave)
Ageratina
    adenophora (Thoroughwort)*
    herbacea (Fragrant snakeroot)
Agropyron
    cristatum ssp. pectinatum (Desert crested wheat grass)*
    desertorum, see Agropyron cristatum ssp. pectinatum
Agoseris
    grandiflora var. grandiflora (Mountain dandelion)
    heterophylla var. heterophylla (Annual mountain dandelion)
    retrorsa (Spearleaf mountain dandelion)
Agrostis
    idahoensis (Idaho bentgrass)
    pallens (Seashore bentgrass)
    viridis, see Polypogon viridis
Ailanthus altissima (Tree of heaven)*
Albizia lophantha (Plume acacia)*
Aliciella
    hutchinsifolia (Desert pale gilia)
    latifolia ssp. latifolia (Broad-leaf gilia)
    leptomeria (Great Basin gilia)
    triodon (Sand gilia)
Alisma plantago-aquatica, see Alisma triviale
Alisma triviale (Water plantain)
Allenrolfea occidentalis (Iodine bush)
Allionia
    incarnata var. incarnata (Trailing windmills)
    incarnata var. villosa (Trailing windmills)
Allium
    amplectens (Narrow-leaved onion)
    atrorubens var. cristatum (Crested 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)
Alopecurus aequalis var. aequalis (Shortawn foxtail)
Aloysia wrightii (Vera dulce)
Amaranthus
    albus (Pigweed amaranth)*
    blitoides (Prostrate amaranth)
    californicus (California amaranth)
    fimbriatus (Fringed amaranth)
    torreyi (Torrey's amaranth)
Amauriopsis dissecta (Ragged-leaf bahia)
Amblyopappus pusillus (Coastweed)
Ambrosia
    acanthicarpa (Annual bur-sage)
    chamissonis (Silver beach bur)
    chenopodiifolia (Goosefoot bur-sage)
    dumosa (Burrobush)
    eriocentra (Woolly bur-sage)
    ilicifolia (Holly-leaved burbush)
    psilostachya (Western ragweed)
    pumila (San Diego ambrosia)
    salsola var. salsola (Cheesebush)
Amelanchier utahensis (Utah serviceberry)
Ammannia coccinea (Red ammannia)
Amorpha
    californica var. californica (California false-indigo)
    fruticosa (Western false-indigo)
Amphipappus fremontii var. fremontii (Chaffbush)
Amsinckia
    intermedia (Common fiddleneck)
    menziesii (Small-flowered fiddleneck)
    menziesii var. intermedia, see Amsinckia intermedia
    menziesii var. menziesii, see Amsinckia menziesii
    spectabilis var. spectabilis (Seaside fiddleneck)
    tessellata var. tessellata (Checker fiddleneck)
Amsonia tomentosa (Woolly amsonia)
Anagallis
    arvensis (Scarlet pimpernel)*
    minima (Common chaffweed)
Anemopsis californica (Yerba mansa)
Angelica
    lineariloba (Soda straw)
    tomentosa (Woolly angelica)
Anisocoma acaulis (Scalebud)
Antennaria
    dimorpha (Low pussytoes)
    media (Alpine 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, see Turritis glabra
    holboelii var. pinetorum, see Boechera pinetorum
    parishii, see Boechera parishii
    perennans, see Boechera perennans
    platysperma var. platysperma, see Boechera platysperma
    pulchra var. gracilis, see Boechera xylopoda
    pulchra var. pulchra, see Boechera pulchra
    rectissima, see Boechera rectissima
    repanda, see Boechera repanda
    shockleyi, see Boechera shockleyi
    sparsiflora var. arcuata, see Boechera arcuata
    sparsiflora var. californica. see Boechera californica
Aralia californica (California aralia)
Arbutus
    menziesii (Pacific madrone)
    menziesii fruit (Pacific madrone)
Arceuthobium campylopodum (Western dwarf mistletoe)
Arctostaphylos
    catalinae (Santa Catalina Island manzanita)
    confertiflora (Santa Rosa Island manzanita)
    gabrielensis, see Arctostaphylos glandulosa ssp. gabrielensis
    glandulosa ssp. crassifolia (Del Mar manzanita)
    glandulosa ssp. adamsii (Adams' manzanita)
    glandulosa ssp. gabrielensis (San Gabriel 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 (Big-berry 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, see Eremogone kingii
    lanuginosa var. saxosa (Spreading sandwort)
    macradenia var. macradenia, see Eremogone macradenia var. macradenia
    ursina, see Eremogone ursina
Argemone
    corymbosa (Mojave prickly poppy)
    munita (Chicalote)
Argyrochosma jonesii (Jones' cloak fern)
Arida arizonica (Silver Lake daisy)
Aristida
    adscensionis (Three-awn)
    purpurea var. nealleyi (Nealley three-awn)
Armeria maritima ssp. californica (California sea-pink)
Arnica
    chamissonis (Meadow arnica)
    mollis (Soft arnica)
Artemisia
    californica (California sagebrush)
    douglasiana (Mugwort)
    dracunculus (Wild tarragon)
    ludoviciana ssp. incompta (Mountain mugwort)
    nova (Black sagebrush)
    palmeri (Palmer's sagewort)
    rothrockii (Rothrock's sagebrush)
    spinescens (Budsage)
    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, see Oreostemma alpigenus var. andersonii
    ascendens, see Symphyotrichum ascendens
    bernardinus, see Symphyotrichum defoliatum
    chilensis, see Symphyotrichum chilense
    greatae, see Symphyotrichum greatae
    lanceolatus var. hesperius, see Symphyotrichum lanceolatum var. hesperium
    occidentalis var. occidentalis, see Symphyotrichum spathulatum var. spathulatum
    subulatus var. ligulatus, see Symphyotrichum subulatum var. paviflorum
Astragalus
    albens (Cushenbury milkvetch)
    aridus (Annual desert milkvetch)
    bicristatus (Crested milkvetch)
    brauntonii (Braunton's rattleweed)
    cimae var. cimae (Cima milkvetch)
    coccineus (Scarlet milkvetch)
    crotalariae (Salton milkvetch)
    curtipes (San Luis Obispo milkvetch)
    didymocarpus var. didymocarpus (Two-seeded milkvetch)
    didymocarpus var. dispermus (Dwarf white 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)
    magdalenae var. peirsonii (Peirson's milkvetch)
    miguelensis (San Miguel milkvetch)
    minthorniae var. villosus (Minthorn's milkvetch)
    newberryi var. newberryi (Newberry's rattleweed)
    nutans (Providence Mountains milkvetch)
    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)
    tricarinatus (Triple-ribbed 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 var. canescens (Fourwing saltbush)
    canescens var. laciniata (Fourwing saltbush)
    confertifolia (Shadscale saltbush)
    covillei (Arrowscale)
    elegans var. fasciculata (Wheelscale saltbush)
    glauca (Waxy saltbush)*
    hymenelytra (Desert-holly)
    lentiformis (Quail bush)
    leucophylla (Beach saltbush)
    pacifica (Pacific saltbush)
    phyllostegia, see Atriplex covillei
    polycarpa (Cattle spinach)
    prostrata (Arrowleaf saltbush)*
    semibaccata (Australian saltbush)*
    triangularis, see Atriplex prostrata
    watsonii (Watson's saltbush)
Avena
    barbata (Slender oats)*
    fatua (Common wild oats)*
Ayenia compacta (Ayenia)
Baccharis
    brachyphylla (Shortleaf baccharis)
    douglasii, see Baccharis glutinosa
    emoryi, see Baccharis salicina
    glutinosa (Salt marsh baccharis)
    malibuensis (Malibu baccharis)
    pilularis ssp. consanguinea (Coyote brush)
    plummerae ssp. plummerae (Plummer's baccharis)
    salicifolia ssp. salicifolia (Mulefat)
    salicina (Willow baccharis)
    sarothroides (Broom baccharis)
    sergiloides (Desert baccharis)
    vanessae (Encinitas baccharis)
Bahia dissecta, see Amauriopsis dissecta
Bahiopsis
    laciniata (San Diego County goldeneye)
    parishii (Parish's goldeneye)
    reticulata (Mojave goldeneye)
Baileya
    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 incana (Bernardia)
Berula erecta (Water parsnip)
Beta vulgaris ssp. maritima (Sea beet)*
Bidens
    laevis (Smooth beggar-ticks)
    pilosa (Common beggar-ticks)*
Bistorta bistortoides (Western bistort)
Bituminaria bituminosa (Pitch trefoil)*
Blennosperma nanum var. nanum (Yellow carpet)
Bloomeria
    crocea var. crocea (Golden stars)
    crocea var. montana (Golden stars)
Boechera
    arcuata (Arched elegant rock-cress)
    californica (Elegant rock-cress)
    parishii (Parish's rock-cress)
    perennans (Perennial rock-cress)
    pinetorum (Pine rock-cress)
    platysperma (Broad-seeded rock-cress)
    pulchra (Beautiful rock-cress)
    rectissima (Bristly-leaved rock-cress)
    repanda (Yosemite rock-cress)
    shockleyi (Shockley's rock-cress)
    xylopoda (Slender beautiful rock-cress)
Boerhavia
    coccinea (Scarlet spiderling)
    coulteri var. palmeri (Coulter's spiderling)
    intermedia, see Boerhavia triquetra var. intermedia
    triquetra var. intermedia (Fivewing spiderling)
    wrightii (Wright's spiderling)
Bolboschoenus maritimus ssp. paludosus (Marsh bulrush)
Boschniakia strobilacea, see Kopsiopsis strobilacea
Botrychium crenulatum (Scalloped moonwort)
Bouteloua
    aristidoides var. aristodoides (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 (Saharan mustard)*
Brickellia
    arguta var. arguta, see Brickellia atractyloides var. arguta
    atractyloides var. arguta (Spearleaf brickellbush)
    californica (California brickellbush)
    desertorum (Desert brickellbush)
    frutescens (Shrubby brickellbush)
    incana (Woolly brickellbush)
    longifolia var. multiflora (Gum-leaved brickellbush)
    microphylla (Little-leaved brickellbush)
    multiflora, see Brickellia longifolia var. multiflora
    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
    berteroanus (Chilean chess)
    carinatus var. carinatus (California brome)
    carinatus var. maritimus, see Bromus maritimus
    diandrus (Ripgut brome)*
    hallii (Hall's brome)
    hordeaceus (Soft chess)*
    madritensis ssp. rubens (Red brome)*
    maritimus (Seaside brome)
    tectorum (Cheat grass)*
    trinii, see Bromus berteroanus
Buddleja utahensis (Panamint butterfly bush)
Bursera microphylla (Elephant tree)
Caesalpinia
    gilliesii (Yellow bird-of-paradise)*
    virgata, see Hoffmanseggia microphylla
Cakile maritima (Sea rocket)*
Calandrinia
    ambigua, see Cistanthe ambigua
    breweri (Brewer's red maids)
    ciliata (Red maids)
    maritima, see Cistanthe maritima
California macrophylla (White-flowered filaree)
Calliandra
    eriophylla (Pink fairy duster)
Callitriche heterophylla var. bolanderi (Water-starwort)
Calocedrus decurrens (Incense-cedar)
Calochortus
    albus (Fairy lantern)
    catalinae (Catalina mariposa lily)
    clavatus var. pallidus (Yellow mariposa lily)
    clavatus var. gracilis (Slender mariposa lily)
    concolor (Golden bowl mariposa lily)
    dunnii (Dunn's mariposa lily)
    fimbriatus (Late-flowering 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. intermedius (Weed's intermediate mariposa lily)
    weedii var. vestus, see Calochortus fimbriatus
    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)
    pygmeum (Pygmy 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, see Camissoniopsis bistorta
    boothii ssp. condensata, see Eremothera boothii ssp. condensata
    boothii ssp. decorticans, see Eremothera boothii ssp. decorticans
    boothii ssp. desertorum, see Eremothera boothii ssp. desertorum
    boothii ssp. intermedia, see Eremothera boothii ssp. intermedia
    brevipes ssp. brevipes, see Chylismia brevipes ssp. brevipes
    californica, see Eulobus californicus
    campestris ssp. campestris (Mojave sun cup)
    cardiophylla ssp. cardiophylla, see Chylismia cardiophylla ssp. cardiophylla
    cheiranthifolia ssp. cheiranthifolia, see Camissoniopsis cheiranthifolia ssp. cheiranthifolia
    cheiranthifolia ssp. suffruticosa, see Camissoniopsis cheiranthifolia ssp. suffruticosa
    claviformis ssp. aurantiaca, see Chylismia claviformis ssp. aurantiaca
    claviformis ssp. claviformis, see Chylismia claviformis ssp. claviformis
    claviformis ssp. funerea, see Chylismia claviformis ssp. funerea
    claviformis ssp. lancifolia, see Chylismia claviformis ssp. lancifolia
    claviformis ssp. peirsonii, see Chylismia claviformis ssp. peirsonii
    confusa, see Camissoniopsis confusa
    hirtella, see Camissoniopsis hirtella
    intermedia, see Camissoniopsis intermedia
    kernensis (Kern sun cup)
    micrantha, see Camissoniopsis micrantha
    pallida, see Camissoniopsis pallida
    palmeri, see Tetrapteron palmeri
    pterosperma, see Chylismiella pterosperma
    pusilla (Little wiry sun cup)
    refracta, see Eremothera refracta
    robusta, see Camissoniopsis robusta
    strigulosa (Strigose sun cup)
    walkeri ssp. tortilis, see Chylisma walkeri ssp. tortilis
Camissoniopsis
    bistorta (Sun cup)
    cheiranthifolia ssp. cheiranthifolia (Channel Islands beach primrose)
    cheiranthifolia ssp. suffruticosa (Beach primrose)
    confusa (San Bernardino sun cup)
    hirtella (Hairy sun cup)
    intermedia (Intermediate sun cup)
    micrantha (Small evening primrose)
    pallida ssp. pallida (Pale primrose)
    robusta (Robust sun cup)
Canbya candida (Pygmy poppy)
Capsella bursa-pastoris (Shepherd's purse)*
Cardamine
    californica (Milkmaids)
    oligosperma (Bitter cress)
Cardionema ramosissimum (Sandmat)
Carduus pycnocephalus ssp. pycnocephalus (Italian thistle)*
Carex
    alma (Sturdy sedge)
    aurea (Golden sedge)
    densa (Dense sedge)
    fracta (Fragile-sheathed sedge)
    heteroneura (Smooth-fruited sedge)
    multicaulis (Forest sedge)
    praegracilis (Clustered field sedge)
    rossii (Ross's sedge)
    senta (Swamp sedge)
    spissa (San Diego sedge)
    subfusca (Rusty slender sedge)
    triquetra (Triangular-fruit sedge)
Carlowrightia arizonica (Arizona carlowrightia)
Carnegiea gigantea (Giant saguaro)
Carpenteria californica (Bush anenome)*
Carpobrotus
    chilensis (Sea fig)*
    edulis (Hottentot fig)*
Carsonia sparsifolia (Naked cleome)
Carthamus tinctorius (Safflower)*
Castela emoryi (Crucifixion thorn)
Castilleja
    affinis ssp. affinis (Coast paintbrush)
    angustifolia, see Castilleja chromosa
    applegatei ssp. martinii (Martin's paintbrush)
    chromosa (Desert indian paintbrush)
    cinerea (Ashy-gray paintbrush)
    densiflora ssp. gracilis (Dense-flowered owl's clover)
    exserta ssp. exserta (Purple owl's clover)
    exserta ssp. venusta (Mojave owl's clover)
    foliolosa (Woolly indian paintbrush)
    hololeuca (Island paintbrush)
    lanata ssp. hololeuca, see Castilleja hololeuca
    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)
    montigena (Heckard's indian paintbrush)
    nana (Dwarf alpine paintbrush)
    plagiotoma (Yellow paintbrush)
    pruinosa (Frosted indian paintbrush)
    tenuis (Hairy owl's clover)
Caulanthus
    amplexicaulis (Clasping-leaved caulanthus)
    cooperi (Cooper's jewelflower)
    coulteri (Coulter's jewelflower)
    crassicaulis (Thickstem wild cabbage)
    hallii (Hall's caulanthus)
    heterophyllus (Slender-pod jewelflower)
    inflatus (Desert candle)
    major (Slender wild cabbage)
    simulans (Payson's jewelflower)
Ceanothus
    arboreus (Island ceanothus)
    cordulatus (Mountain whitethorn)
    crassifolius (Hoaryleaf ceanothus)
    cuneatus var. cuneatus (Buckbrush)
    cyaneus (Lakeside ceanothus)
    greggii var. perplexans, see Ceanothus perplexans
    greggii var. vestitus, see Ceanothus vestitus
    integerrimus var. macrothyrsus (Deerbrush)
    leucodermis (Chaparral whitethorn)
    megacarpus var. megacarpus (Big-pod ceanothus)
    oliganthus var. oliganthus (Hairy ceanothus)
    oliganthus var. sorediatus (Jim brush)
    palmeri (Palmer's ceanothus)
    papillosus (Wartleaf ceanothus)
    perplexans (Cupleaf ceanothus)
    spinosus (Greenbark ceanothus)
    tomentosus (Woollyleaf ceanothus)
    verrucosus (Wartstem ceanothus)
    vestitus (Mojave ceanothus)
Celtis reticulata (Western hackberry)
Centaurea
    benedictus (Blessed thistle)*
    maculosa, see Centaurea stoebe ssp. micranthos
    melitensis (Tocalote)*
    solstitialis (Yellow star thistle)*
    stoebe ssp. micranthos (Spotted knapweed)*
Centaurium venustum, see Zeltnera venusta
Centranthus ruber (Red valerian)*
Centromadia
    parryi ssp. australis(Southern tarplant)
    pungens (Spikeweed)
Centrostegia thurberi (Thurber's spineflower)
Centunculus minimus, see Anagallis minima
Cerastium
    fontanum ssp. vulgare (Perennial chickweed)*
    glomeratum (Mouse-ear chickweed)*
Cercidium
    floridum ssp. floridum, see Parkinsonia florida
    microphyllum. see Parkinsonia microphylla
Cercis occidentalis (Western redbud)
Cercocarpus
    betuloides var. betuloides (Birch-leaf mountain mahogany)
    betuloides var. blancheae (Island mountain mahogany)
    intricatus, see Cercocarpus ledifolius var. intricatus
    ledifolius var. 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)
    glabriuscula var. orcuttiana (Orcutt's 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)
Chamerion angustifolium ssp. circumvagum (Fireweed)
Chamomilla suaveolens, see Matricaria matricarioides
Chasmanthe floribunda (South African cornflag)*
Cheilanthes
    clevelandii (Cleveland's lipfern)
    cooperae (Mrs. Cooper'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, see Dysphania ambrosioides
    atrovirens (Forest goosefoot)
    botrys, see Dysphania botrys
    californicum (California goosefoot)
    fremontii (Fremont's goosefoot)
    hians (Gaping goosefoot)
    macrospermum (Coast goosefoot)*
    murale (Nettleleaf goosefoot)*
    pratericola (Meadow goosefoot)
Chilopsis linearis ssp. arcuata (Desert willow)
Chimaphila
    menziesii (Little prince's pine)
    umbellata (Pipsissewa)
Chloracantha spinosa var. spinosa (Spiny aster)
Chlorogalum
    parviflorum (Small-flowered soap plant)
    pomeridianum var. pomeridianum (Soap plant)
Chloropyron maritium ssp. maritimum (Salt marsh bird's beak)
Chondrilla juncea (Skeleton weed)*
Chorizanthe
    brevicornu var. brevicornu (Brittle spineflower)
    corrugata (Wrinkled spineflower)
    fimbriata var. fimbriata (Fringed spineflower)
    fimbriata var. laciniata (Lace-fringed spineflower)
    membranacea (Pink 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)
    xanti var. xanti (Xantus' spineflower)
Chrysanthemum coronarium, see Glebionis coronaria
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, see Ericameria nauseosa var. oreophila
    nauseosus ssp. hololeucus, see Ericameria nauseosa var. hololeuca
    nauseosus ssp. mohavensis, see Ericameria nauseosa var. mohavensis
    paniculatus, see Ericameria paniculata
    parryi ssp. asper, see Ericameria parryi var. aspera
    teretifolius, see Ericameria teretifolia
    viscidiflorus ssp. viscidiflorus (Sticky-leaved rabbitbrush)
Chylismia
    brevipes ssp. brevipes (Yellow cups)
    cardiophyla ssp. cardiophylla (Heartleaf sun cup)
    claviformis ssp. aurantiaca (Browneyes)
    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)
    walkeri ssp. tortilis (Walker's sun cup)
Chylismiella pterosperma (Wingfruit sun cup)
Cichorium intybus (Chicory)*
Cirsium
    arizonicum var. tenuisectum (Red thistle)
    mohavense (Mojave thistle)
    neomexicanum(Desert thistle)
    nidulum, see Cirsium arizonicum var. tenuisectum
    occidentale var. californicum (California thistle)
    occidentale var. occidentale (Cobweb thistle)
    occidentale var. venustum (Venus thistle)
    scariosum (Elk thistle)
    vulgare (Bull thistle)*
Cistanthe
    ambigua (Desert pot-herb)
    maritima (Seaside red maids)
Cistus
    creticus, see Cistus incanus
    incanus (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. clavicarpa (Speckled clarkia)
    cylindrica ssp. cylindrica (Speckled clarkia)
    dudleyana (Dudley's clarkia)
    epilobioides (Canyon clarkia)
    heterandra (Mountain 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, see Carsonia sparsifolia
Cleomella obtusifolia (Mojave stinkweed)
Clinopodium
    chandleri (San Diego satureja)
    douglasii (Yerba buena)
    mimuloides (Monkeyflower savory)
Cneoridium dumosum (Bushrue)
Cnicus benedictus, see Centaurea benedictus
Coleogyne ramosissima (Blackbrush)
Collinsia
    bartsiifolia var. davidsonii (Davidson's blue-eyed mary)
    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)*
Comandra umbellata ssp. californica (California bastard toadflax)
Comarostaphylis
    diversifolia ssp. diversifolia (Summer-holly)
    diversifolia ssp. planifolia (Summer-holly)
Conium maculatum (Poison hemlock)*
Constancea nevinii (Nevin's woolly sunflower)
Convolvulus
    arvensis (Bindweed)*
    simulans (Small-flowered morning glory)
Conyza
    bonariensis*, see Erigeron bonariensis
    canadensis, see Erigeron canadensis
    coulteri, see Laennecia coulteri
    floribunda*, see Erigeron sumatrensis
Corallorhiza maculata (Spotted coralroot)
Cordylanthus
    maritimus ssp. maritimus, see Chloropyron maritium ssp. maritimum
    nevinii (Nevin's bird's beak)
    orcuttianus (Orcutt's bird's beak)
    parviflorus (Purple bird's beak)
    rigidus ssp. rigidus (Bristly bird's beak)
    rigidus ssp. setigerus (Bristly bird's beak)
Coreopsis
    bigelovii, see Leptosyne bigelovii
    californica var. californica, see Leptosyne californica
    gigantea, see Leptosyne gigantea
    maritima, see Leptosyne maritima
Corethrogyne filaginifolia (California aster)
Cornus
    nuttallii (Mountain dogwood)
    sericea ssp. sericea (American dogwood)
Coronopus didymus, see Lepidium didymum
Cortaderia selloana (Pampas grass)*
Coryphantha
    alversonii (Alverson's spinystar)
    chlorantha (Desert spinystar)
    vivipara var. rosea (Rosy spinystar)
Cosmos bipinnatus (Mexican aster)*
Cotula
    australis (Australian brass-buttons)*
    coronopifolia (Brass-buttons)*
Crassula
    aquatica (Water pygmy weed)
    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)
    setiger (Doveweed)
    wigginsii (Wiggins's croton)
Cryptantha
    angustifolia (Narrow-leaved cryptantha)
    barbigera var. barbigera (Bearded cryptantha)
    barbigera var. fergusoniae (Ferguson's bearded cryptantha)
    cinerea var. abortiva (Bownut cryptantha)
    circumscissa var. circumscissa (Cushion cryptantha)
    clevelandii (Cleveland's cryptantha)
    confertiflora (Yellow cryptantha)
    costata (Ribbed cryptantha)
    decipiens (Gravel cryptantha)
    dumetorum (Bush-loving cryptantha)
    echinella (Prickly cryptantha)
    flavoculata (Roughseed cryptantha)
    intermedia var. intermedia (Large-flowered cryptantha)
    maritima (Guadalupe cryptantha)
    micrantha (Smallflower cryptantha)
    micromeres (Minute-flowered cryptantha)
    microstachys (Tejon cryptantha)
    mohavensis (Mojave cryptantha)
    muricata (Prickly cryptantha)
    nevadensis (Nevada cryptantha)
    pterocarya (Wingnut cryptantha)
    recurvata (Curvenut cryptantha)
    simulans (Pinewoods cryptantha)
    tumulosa (New York Mountains cryptantha)
    utahensis (Scented cryptantha)
    virginensis (Virgin River cryptantha)
Cryptogramma agrostichoides (American rock-brake)
Cucurbita
    foetidissima (Calabazilla)
    foetidissima fruit (Calabazilla)
    palmata (Coyote melon)
Cupressus
    arizonica ssp. arizonica, see Hesperocyparis stephensonii
    forbesii, see Hesperocyparis forbesii
Cuscuta
    californica var. breviflora. see Cuscuta occidentalis
    californica var. californica (California dodder)
    californica var. papillosa (Papillate dodder)
    campestris (Western field dodder)
    denticulata (Desert dodder)
    occidentalis (Short-flowered California dodder)
    pentagona, see Cuscuta campestris
    salina (Salt marsh dodder)
    subinclusa (Canyon dodder)
Cusickiella douglasii (Alkali draba)
Cycladenia humilis var. venusta (Showy cycladenia)
Cylindropuntia
    acanthocarpa var. coloradensis (Buckhorn cholla)
    bigelovii (Jumping cholla)
    californica var. parkeri (Valley cholla)
    echinocarpa (Silver cholla)
    ganderi (Gander's cholla)
    prolifera (Coast cholla)
    ramosissima (Pencil cholla)
    wolfii (Wolf'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)*
    laevigatus (Smooth flatsedge)
Cystopteris fragilis (Brittle fern)
Cytisus striatus (Portuguese broom)*
Dactylis glomerata (Orchard grass)*
Dalea
    mollis (Silky dalea)
    mollissima (Downy dalea)
Dasyochloa pulchella (Fluff grass)
Datisca glomerata (Durango root)
Datura
    discolor (Desert thornapple)
    wrightii (Sacred datura)
Daucus pusillus (American wild carrot)
Dedeckera eurekensis (July gold)
Deinandra
    arida (Red Rock tarplant)
    clementina (Island tarplant)
    conjugens (Otay tarplant)
    fasciculata (Slender tarplant)
    minthornii (Santa Susana tarplant)
    mohavensis (Mojave tarplant)
    paniculata (San Diego tarplant)
Delairea odorata (Cape-ivy)*
Delphinium
    cardinale (Scarlet larkspur)
    glaucum (Mountain larkspur)
    hansenii ssp. kernense (Kern larkspur)
    parishii ssp. pallidum (Pale larkspur)
    parishii ssp. parishii (Desert larkspur)
    parishii ssp. subglobosum (Ocean blue larkspur)
    parryi ssp. parryi (Blue larkspur)
    patens ssp. hepaticoideum (Spreading larkspur)
    patens ssp. montanum (Spreading larkspur)
Dendromecon
    harfordii (Channel Island tree poppy)
    rigida (Bush poppy)
Deschampsia elongata (Slender hairgrass)
Descurainia
    californica (Sierra tansy mustard)
    incana (Mountain tansy mustard)
    incisa (Mountain tansy mustard)
    pinnata (Tansy mustard)
Dicentra
    chrysantha, see Ehrendorferia chrysantha
    ochroleuca, see Ehrendorferia ochroleuca
Dichelostemma capitatum ssp. capitatum (Blue dicks)
Dichondra occidentalis (Western dichondra)
Dicoria canescens (Desert dicoria)
Dicranostegia  orcuttiana (Orcutt's bird's beak)
Dieteria
    asteroides var. asteroides (Scrub aster)
    asteroides var. lagunensis (Laguna Mountains aster)
    canescens var. canescens (Hoary-aster)
    canescens var. leucanthemifolia (Desert hoary-aster)
    canescens var. ziegleri (Ziegler's aster)
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
    albertina (Slender draba)
    corrugata (Southern California draba)
    cuneifolia (California draba)
    saxosa (Southern California rock draba)
    verna (Spring draba)
Drymocallis
    cuneifolia var. ewanii (Ewan's cinquefoil)
    glandulosa var. reflexa (Sticky cinquefoil)
    glandulosa var. viscida (Sticky cinquefoil)
    glandulosa var. wrangelliana (Sticky cinquefoil)
    lactea var. lactea (Nevada cinquefoil)
Dryopteris arguta (Coastal wood fern)
Duchesnea indica var. 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. agourensis (Agoura dudleya)
    cymosa ssp. crebifolia (San Gabriel River dudleya)
    cymosa ssp. cymosa (Canyon dudleya)
    cymosa ssp. pumila (Low canyon dudleya)
    densiflora (San Gabriel Mountains dudleya)
    edulis (Ladies' fingers)
    greenei (Greene's dudleya)
    hassei, see Dudleya virens ssp. hassei
    lanceolata (Lanceleaf dudleya)
    multicaulis (Many-stemmed dudleya)
     pulverulenta (Chalk dudleya)
    saxosa ssp. aloides (Rock dudleya)
    traskiae (Santa Barbara Island dudleya)
    variegata (Variegated dudleya)
    virens ssp. hassei (Hasse's dudleya)
    viscida (Sticky dudleya)
Dysphania
    ambrosioides (Mexican-tea)*
    botrys (Jerusalem-oak goosefoot )*
Echinocactus polycephalus var. polycephalus (Cottontop cactus)
Echinocereus
    engelmannii (Engelmann's hedgehog cactus)
    mohavensis (Mojave mound cactus)
    triglochidiatus, see Echinocereus mohavensis
Echinodorus berteroi (Burhead)
Ehrendorferia
    chrysantha (Golden ear drops)
    ochroleuca (Bleeding hearts)
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)
    hispidus (Intermediate wheat grass)*
    ponticus (Tall wheat grass)*
    trachycaulus ssp. trachycaulus (Slender wheat grass)
Elytrigia
    intermedia ssp. intermedia, see Elymus hispidus
    pontica ssp. pontica, see Elymus ponticus
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
    aspera (Rough joint-fir)
    californica (California ephedra)
    nevadensis (Nevada ephedra)
    viridis (Green ephedra)
Epilobium
    angustifolium ssp. circumvagum, see Chamerion angustifolium ssp. circumvagum
    brachycarpum (Field willow-herb)
    campestre (Smooth boisduvalia)
    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)
    hallianum (Hall's willow-herb)
    lactiflorum (Milkflower willow-herb)
    oregonense (Oregon willow-herb)
    pygmaeum, see Epilobium campestre
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, see Croton setiger
Eremogone
    kingii var. glabrescens (King's sandwort)
    macradenia var. macradenia (Desert sandwort)
    ursina (Bear valley sandwort)
Eremothera
    boothii ssp. condensata (Booth's clustered evening primrose)
    boothii ssp. decorticans (Booth's shredding evening primrose)
    boothii ssp. desertorum (Booth's desert evening primrose)
    boothii ssp. intermedia (Booth's intermediate evening primrose)
    refracta (Narrow-leaf suncup)
Eriastrum
    densifolium ssp. austromontanum (Southern mountain woolstar)
    densifolium ssp. elongatum (Giant 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
    albida (White-flowered rabbitbrush)
    arborescens (Golden-fleece)
    brachylepis (Boundary goldenbush)
    cooperi var. cooperi (Cooper's goldenbush)
    cuneata var. cuneata (Rock goldenbush)
    cuneata var. macrocephala (Laguna Mountains 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)
    nauseosa var. mohavensis (Mojave rubber rabbitbrush)
    nauseosa var. oreophila (Threadleaf rubber rabbitbrush)
    palmeri var. pachylepis (Palmer's goldenbush)
    paniculata (Black-banded rabbitbrush)
    parishii var. parishii (Parish's goldenbush)
    parryi ssp. aspera (Parry's rabbitbrush)
    pinifolia (Pine goldenbush)
    teretifolia (Green rabbitbrush)
Erigeron
    aphanactis var. congestus (Rayless fleabane)
    bonariensis (Small horseweed)*
    breweri var. breweri (Brewer's fleabane)
    breweri var. covillei (Coville's fleabane)
    breweri var. jacinteus (San Jacinto Mountains fleabane)
    canadensis (Tall horseweed)
    compositus (Cutleaf daisy)
    concinnus (Navajo fleabane)
    divergens (Spreading fleabane)
    foliosus var. foliosus (Leafy daisy)
    glaucus (Seaside daisy)
    parishii (Parish's fleabane)
    sumatrensis (Asthmaweed)*
Eriodictyon
    crassifolium (Thickleaf yerba santa)
    parryi (Poodle-dog bush)
    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 (Ashy-leaf 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)
    rixfordii (Rixford's buckwheat)
    saxatile (Rock buckwheat)
    thomasii (Thomas' buckwheat)
    thornei (Thorne's buckwheat)
    trichopes (Little desert trumpet)
    umbellatum var. minus (Alpine sulphur-flowered buckwheat)
    umbellatum var. munzii (Munz's buckwheat)
    umbellatum var. nevadense (Nevada buckwheat)
    umbellatum var. subaridum (Sulphur-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, see Dasyochloa pulchella
Eriophyllum
    ambiguum var. paleaceum (Yellow-frocks)
    confertiflorum var. confertiflorum (Golden yarrow)
    lanatum var. obovatum (Woolly sunflower)
    lanosum (White easter bonnets)
    nevinii, see Constancea nevinii
    pringlei (Pringle eriophyllum)
    wallacei (Woolly daisy)
Erodium
    botrys (Long-beaked storksbill)*
    brachycarpum (Short-fruited filaree)*
    cicutarium (Red-stem filaree)*
    macrophyllum, see California macrophylla
    moschatum (Whitestem filaree)*
    texanum (Desert heron's bill)
Eryngium aristulatum var. parishii (San Diego button-celery)
Erysimum
    capitatum var. capitatum (Western wallflower)
    insulare (Island wallflower)
Eschscholzia
    caespitosa (Tufted poppy)
    californica (California poppy)
    glyptosperma (Desert gold poppy)
    minutiflora (Little gold poppy)
    parishii (Parish's poppy)
Escobaria
    vivipara var. alversonii, see Coryphantha alversonii
    vivipara var. deserti, see Coryphantha chlorantha
    vivipara var. rosea, see Coryphantha vivipara var. rosea
Eucalyptus globulus (Blue gum)*
Eucnide urens (Desert rocknettle)
Eucrypta
    chrysanthemifolia var. bipinnatifida (Common eucrypta)
    chrysanthemifolia var. chrysanthemifolia (Common eucrypta)
    micrantha (Small-flowered eucrypta)
Eulobus californicus (Mustard evening primrose)
Euonymus occidentalis var. parishii (Burning bush)
Euphorbia
    characias (Bush spurge)*
    crenulata (Chinese caps)
    eriantha (Beetle spurge)
    incisa, see Euphorbia schizoloba
    lathyris (Caper spurge)*
    lurida (Woodland spurge)
    misera (Cliff spurge)
    palmeri, see Euphorbia lurida
    peplus (Petty spurge)*
    schizoloba (Mojave spurge)
    spathulata (Warty spurge)
    terracina (Terracina spurge)*
Eustoma exaltatum ssp. exaltatum (Catchfly gentian)
Euthamia occidentalis (Western goldenrod)
Fagonia
    laevis (Smooth-stemmed fagonia)
    pachyacantha (Sticky fagonia)
Fallugia paradoxa (Apache plume)
Ferocactus
    cylindraceus (California barrel cactus)
    viridescens (Coast barrel cactus)
Festuca arundinacea (Tall fescue)*
Ficus carica (Edible fig)*
Filago
    californica, see Logfia filaginoides
    depressa, see Logfia depressa
    gallica, see Logfia gallica
Foeniculum vulgare (Sweet fennel)*
Forestiera pubescens (Desert olive)
Fouquieria splendens ssp. splendens (Ocotillo)
Fragaria vesca (Wild strawberry)
Frangula 
    californica ssp. californica (Coffeeberry)
    californica ssp. cuspidata (Sierra hoary coffeeberry)
    californica ssp. tomentella (Hoary coffeeberry)
Frankenia
    palmeri (Palmer's frankenia)
    salina (Alkali heath)
Fraxinus
    dipetala (California ash)
    velutina (Velvet ash)
Fremontodendron
    californicum (Flannel bush)
    mexicanum (Mexican flannel bush)
Fritillaria
    biflora var. biflora (Chocolate lily)
    pinetorum (Pinewoods fritillary)
Funastrum
    cynanchoides var. hartwegii (Climbing milkweed)
    hirtellum (Hairy milkweed)
Galium
    andrewsii ssp. andrewsii (Phlox-leaved bedstraw)
    andrewsii ssp. intermedium (Phlox-leaved bedstraw)
    angustifolium ssp. angustifolium (Narrow-leaved bedstraw)
    angustifolium ssp. foliosum (Leafy bedstraw)
    angustifolium ssp. gabrielense (San Antonio Canyon bedstraw)
    angustifolium ssp. gracillimum (Slender bedstraw)
    angustifolium ssp. jacinticum (San Jacinto Mountains bedstraw)
    angustifolium ssp. nudicaule (Naked-stem bedstraw)
    aparine (Annual bedstraw)*
    bifolium (Twinleaf bedstraw)
    buxifolium (Boxwood-leaved bedstraw)
    californicum ssp. miguelense (San Miguel Island bedstraw)
    catalinense (Catalina Island bedstraw)
    hallii (Nodding bedstraw)
    hilendiae ssp. hilendiae (Hilend's bedstraw)
    murale (Tiny bedstraw)*
    nuttallii ssp. insulare (Nuttall's island bedstraw)
    nuttallii ssp. nuttallii (Climbing bedstraw)
    parishii (Parish's bedstraw)
    parisiense (Wall bedstraw)*
    porrigens var. porrigens (Graceful bedstraw)
    stellatum (Star-flowered bedstraw)
    trifidum ssp. columbianum (Three-petal bedstraw)
    trifidum ssp. subbiflorum (Three-petal bedstraw)
Galvezia speciosa, see Gambelia speciosa
Gambelia speciosa (Showy island snapdragon)
Gamochaeta ustulata (Purple cudweed)
Garrya
    elliptica (Coast silktassel)
    flavescens (Ashy silktassel)
    fremontii (Fremont's silktassel)
    veatchii (Canyon silktassel)
Gastridium
    phleoides (Nit grass)*
    ventricosum, see Gastridium phleoides
Gaura
    coccinea, see Oenothera suffrutescens
    sinuata, see Oenothera sinuosa
Gayophytum
    diffusum ssp. parviflorum (Small-flowered groundsmoke)
    heterozygum (Zig-zag groundsmoke)
    oligospermum (Pinegrove groundsmoke)
Genista
    linifolia (Mediterranean broom)*
    monspessulana (French broom)*
Gentiana fremontii (Moss gentian)
Gentianella amarella ssp. acuta (Autumn dwarf gentian)
Gentianopsis simplex (One flower fringed gentian)
Geraea canescens (Desert sunflower)
Geranium
    californicum (California geranium)
    carolinianum (Carolina geranium)
    dissectum (Cutleaf geranium)*
    rotundifolium (Roundleaf geranium)*
Geum macrophyllum var. perincisum (Large-leaved avens)
Gilia
    aliquanta ssp. aliquanta (Puff-calyx gilia)
    aliquanta ssp. breviloba (Western gilia)
    angelensis (Chaparral gilia)
    australis, see Saltugilia australis
    brecciarum ssp. neglecta (Argus gilia)
    campanulata, see Linanthus campanulatus
    cana ssp. bernardina (Showy gilia)
    cana ssp. triceps (Showy gilia)
    capitata ssp. abrotanifolia (Globe gilia)
    caruifolia, see Saltugilia caruifolia
    clokeyi (Clokey's gilia)
    diegensis (San Diego gilia)
    filiformis, see Linanthus filiformis
    hutchinsifolia, see Aliciella hutchinsifolia
    latiflora ssp. latiflora (Broad-flowered gilia)
    latiflora ssp. davyi (Davy gilia)
    latifolia, see Aliciella latifolia ssp. latifolia
    leptantha ssp. leptantha (Fine-flower gilia)
    leptantha ssp. purpusii (Purpus's gilia)
    leptantha ssp. transversa (Transverse fine-flower gilia)
    maculata, see Linanthus maculatus
    minor (Little gilia)
    modocensis (Modoc gilia)
    ochroleuca ssp. bizonata (Volcanic gilia)
    ochroleuca ssp. exilis (Slender volcanic gilia)
    ochroleuca ssp. vivida (Volcanic gilia)
    ophthalmoides (Eyed gilia)
    scopulorum (Rock gilia)
    sinuata (Rosy gilia)
    splendens ssp. grantii, see Saltugilia splendens ssp. grantii
    splendens ssp. splendens, see Saltugilia ssp. splendens
    stellata (Star gilia)
    transmontana (Transmontane gilia)
    tricolor ssp. diffusa (Birdseye gilia)
    triodon, see Aliciella triodon
Githopsis
    diffusa ssp. candida (White-flowered bluecup)
    diffusa ssp. diffusa (San Gabriel bluecup)
Glebionis coronaria (Garland chrysanthemum)*
Glossopetalon spinescens var. aridum (Spiny greasebush)
Glyceria elata (Fowl mannagrass)
Glycyrrhiza lepidota (Wild licorice)
Gnaphalium
    bicolor, see Pseudognaphalium biolettii
    californicum, see Pseudognaphalium californicum
    canescens ssp. beneolens, see Pseudognaphalium beneolens
    canescens ssp. microcephalum, see Pseudognaphalium microcephalum
    canescens ssp. thermale, see Pseudognaphalium thermale
    luteo-album, see Pseudognaphalium luteoalbum
    palustre (Lowland cudweed)
    purpureum, see Gamochaeta ustulata
    ramosissimum, see Pseudognaphalium ramosissimum
    stramineum, see Pseudognaphalium stramineum
Grayia spinosa (Spiny hopsage)
Grindelia
    camporum (Gumplant)
    hallii (San Diego gumplant)
    stricta var. platyphylla (Coastal gumplant)
Guillenia lasiophylla (California mustard)
Gutierrezia
    californica (California matchweed)
    microcephala (Sticky snakeweed)
    sarothrae (Broom snakeweed)
Harpagonella palmeri (Palmer's grappling hook)
Hazardia
    brickellioides (Holly-leaved hazardia)
    detonsa (Island hazardia)
    squarrosa var. grindelioides (Sawtooth goldenbush)
Hecastocleis shockleyi (Shockley's prickleleaf)
Hedera helix (English ivy)*
Hedeoma nanum ssp. californicum (California false pennyroyal)
Hedypnois cretica (Crete weed)*
Helenium
    bigelovii (Bigelow's sneezeweed)
    puberulum (Sneezeweed)
Helianthemum scoparium (Rush-rose)
Helianthus
    annuus (Common sunflower)
    californicus (California sunflower)
    gracilentus (Slender-leaved sunflower)
    niveus ssp. canescens (Dune sunflower)
    niveus ssp. tephrodes (Algodones Dunes sunflower)
Heliomeris multiflora var. nevadensis (Nevada golden-eye)
Heliotropium curassavicum (Wild heliotrope)
Helminthotheca echioides (Bristly ox-tongue)*
Hemizonella minima (Pygmy madia)
Hemizonia
    arida, see Deinandra arida
    clementina, see Deinandra clementina
    conjugens, see Deinandra conjugens
    fasciculata, see Deinandra fasciculata
    minthornii, see Deinandra minthornii
    mohavensis, see Deinandra mohavensis
    paniculata, see Deinandra paniculata
    parryi ssp. australis, see Centromadia parryi ssp. australis
    pungens, see Centromadia pungens
Heracleum lanatum, see Heracleum maximum
Heracleum maximum (Cow parsnip)
Hernieria hirsuta ssp. cinerea (Gray hernieria)*
Hesperevax acaulis var. ambusticola (Fire evax)
Hesperocallis undulata (Desert lily)
Hesperochiron californicus (California hesperochiron)
Hesperocnide tenella (Black hair nettle)
Hesperocyparis
    stephensonii (Cuyamaca cypress)
    forbesii (Tecate cypress)
Hesperolinon micranthum (Small-flowered dwarf flax)
Hesperoyucca whipplei (Chaparral yucca)
Heterocodon rariflorum (Few-flowered heterocodon)
Heteromeles
    arbutifolia (Toyon)
    arbutifolia berries (Toyon)
Heterotheca
    grandiflora (Telegraph weed)
    sessiliflora ssp. echioides (Bristly golden-aster)
    sessiliflora ssp. fastigiata (Erect golden-aster)
Heuchera
    abramsii (Abrams' alumroot)
    brevistaminea (Mount Laguna alumroot)
    caespitosa (Urn-flowered alumroot)
    elegans, see Heuchera caespitosa
    hirsutissima (Shaggy-haired alumroot)
    maxima (Island alumroot)
    parishii (San Bernardino Mountains alumroot)
    rubescens var. alpicola (Pink alumroot)
Hibiscus denudatus (Rock hibiscus)
Hieracium
    albiflorum (White-flowered hawkweed)
    argutum (Hawkweed)
    horridum (Shaggy hawkweed)
Hilaria rigida (Big galleta grass)
Hirschfeldia incana (Mediterranean mustard)*
Hoffmannseggia microphylla (Hoffmannseggia)
Hoita
    macrostachya (Leather root)
    orbicularis (Roundleaf leather root)
Holocarpha
    heermannii (Heermann's tarplant)
    virgata ssp. elongata (Graceful tarplant)
Holodiscus
    discolor var. discolor (Cream bush)
    discolor var. microphyllus (Small-leaved cream bush)
    microphyllus var. microphyllus, see Holodiscus discolor var. microphyllus
Hordeum
    brachyantherum ssp. californicum (Meadow barley)
    intercedens (Bobtail barley)
    murinum ssp. glaucum (Foxtail barley)*
    murinum ssp. leporinum (Hare barley)*
Horkelia
    clevelandii (Cleveland's horkelia)
    cuneata (Wedge-leaf horkelia)
    rydbergii (Rydberg's horkelia)
    truncata (Ramona horkelia)
    wilderae (Barton Flats horkelia)
Horsfordia newberryi (Newberry's velvet mallow)
Hosackia
    crassifolius var. crassifolius (Broad-leaved lotus)
    oblongifolia var. oblongifolia (Streambank lotus)
Hulsea
    algida (Alpine gold hulsea)
    californica (San Diego hulsea)
    heterochroma (Red-rayed hulsea)
    vestita ssp. callicarpha (Beautiful hulsea)
    vestita ssp. gabrielensis (San Gabriel Mountains hulsea)
    vestita ssp. parryi (Parry's hulsea)
    vestita ssp. pygmaea (Pygmy hulsea)
Hutchinsia procumbens (Prostrate hutchinsia)
Hymenoclea salsola var. salsola, see Ambrosia salsola var. salsola
Hymenopappus filifolius var. lugens (Columbia cutleaf)
Hymenothrix wrightii (Wright's thimblehead)
Hymenoxys acaulis var. arizonica, see Tetraneuris acaulis var. arizonica
Hymenoxys cooperi (Cooper's goldflower)
Hypericum
    anagalloides (Tinker's penny)
    formosum var. scouleri (Scouler's St. John's wort)
Hypochaeris
    glabra (Smooth cat's ear)*
    radicata (Rough cat's ear)*
Hyptis emoryi (Desert lavender)
Ipomopsis
    arizonica (Arizona ipomopsis)
    polycladon (Spreading gilia)
Iris
    douglasiana (Douglas's iris)
    hartwegii ssp. australis (Hartweg's iris )
    missouriensis (Western blue flag)
Isocoma
    acradenia var. acradenia (Alkali goldenbush)
    acradenia var. bracteosa (Alkali goldenbush)
    acradenia var. eremophila (Alkali goldenbush)
    menziesii var. menziesii (Menzies' goldenbush)
    menziesii var. sedoides (Prostrate coast goldenbush)
    menziesii var. vernonioides (Coast goldenbush)
Isomeris arborea, see Peritoma arborea
Iva
    axillaris ssp. robustior (Poverty weed)
    hayesiana (Poor man's timothy)
Ivesia
    argyrocoma (Silver-haired ivesia)
    callida (Tahquitz ivesia)
    santolinoides (Mousetail ivesia)
    saxosa (Rock ivesia)
Jaumea carnosa (Marsh jaumea)
Jepsonia parryi (Parry's jepsonia)
Juglans
    californica var. californica (female flowers) (California black walnut)
    californica var. californica (fruit) (California black walnut)
    californica var. californica (male flowers) (California black walnut)
Juncus
    acutus ssp. leopoldii (Spiny rush)
    balticus (Wire rush)
    bryoides (Moss rush)
    bufonius var. bufonius (Common toad rush)
    bufonius var. congestus (Clustered toad rush)
    bufonius var. occidentalis (Western toad rush)
    dubius (Mariposa rush)
    effusus var. pacificus (Pacific rush)
    macrandus (Long-anthered rush) 
    macrophyllus (Long-leaved rush)
    mexicanus (Mexican rush)
    patens (Spreading rush)
    phaeocephalus var. paniculatus (Brown-headed rush)
    rugulosus (Wrinkled rush)
    saximontanus (Rocky Mountain rush)
    textilis (Basket rush)
    tiehmii (Tiehm's rush)
    xiphioides (Iris-leaved rush)
Juniperus
    californica (California juniper)
    grandis (Western juniper)
    occidentalis var. australis, see Juniperus grandis
    osteosperma (Utah juniper)
Justicia
    californica (Chuparosa)
Kallstroemia
    californica (California kallstroemia)
    parviflora (Few-flowered caltrop)
Keckiella
    antirrhinoides var. antirrhinoides (Yellow penstemon)
    antirrhinoides var. microphylla (Little-leaved yellow penstemon)
    cordifolia (Heartleaf penstemon)
    rothrockii var. jacintensis (San Jacinto Mountains keckiella)
    rothrockii var. rothrockii (Rothrock's keckiella)
    ternata var. septentrionalis (Northern blue-stemmed keckiella)
    ternata var. ternata (Whorl-leaf penstemon)
Kelloggia galioides (Kelloggia)
Kickxia elatine (Sharpleaf cancerwort)*
Koeleria macrantha (Junegrass)
Kopsiopsis strobilacea (California groundcone)
Krameria
    erecta (Littleleaf rhatany)
    grayi (White rhatany)
Krascheninnikovia lanata (Winterfat)
Lactuca
    saligna (Willowleaf lettuce)*
    serriola (Prickly lettuce)*
Laennecia coulteri (Coulter's horseweed)
Lagophylla ramosissima (Branched hareleaf)
Lamarckia aurea (Goldentop grass)*
Lamium amplexicaule (Henbit)*
Langloisia
    setosissima ssp. punctata (Lilac sunbonnets)
     setosissima ssp. setosissima (Bristly langloisia)
Lappula redowskii var. cupulata (Stickseed)
Larrea tridentata (Creosote bush)
Lastarriaea coriacea (Leather spineflower)
Lasthenia
    californica ssp. californica (California goldfields)
    coronaria (Royal goldfields)
    glaberrima (Rayless goldfields)
    gracilis (Goldfields)
Lathyrus
    latifolius (Perennial sweet pea)*
    vestitus var. alefeldii (San Diego pea)
    vestitus var. vestitus (Canyon sweet pea)
Lavatera
    assurgentiflora (Island mallow)
    cretica (Cretan mallow)*
Layia
    glandulosa (White tidy tips)
    platyglossa (Yellow tidy tips)
Lemna turionifera (Turion duckweed)
Lepechinia
    cardiophylla (Heartleaf pitcher sage)
    fragrans (Fragrant pitcher sage)
Lepidium
    didymum (Wart cress)*
    flavum var. flavum (Yellow peppergrass)
    fremontii var. fremontii (Desert alyssum)
    lasiocarpum var. lasiocarpum (Hairy-podded peppergrass)
    latifolium (Perennial peppergrass)*
    montanum var. cinereum (Mountain peppergrass)
    nitidum var. nitidum (Shiny peppergrass)
    perfoliatum (Clasping pepperweed)*
    virginicum ssp. menziesii (Wild peppergrass)
Lepidospartum
    latisquamum (Nevada broomsage)
    squamatum (Scalebroom)
Leptodactylon
    californicum, see Linanthus californicus
    jaegeri, see Linanthus jaegeri
    pungens, see Linanthus pungens
Leptosiphon
   aureus ssp. aureus (Golden gilia)
    aureus ssp. decorus (Cream gilia)
    breviculus (Mojave linanthus)
    ciliatus (Whiskerbrush)
    floribundus ssp. floribundus (Summer snow linanthus)
    floribundus ssp. glaber (Summer snow linanthus)
    floribundus ssp. hallii (Santa Rosa Mountains linanthus)
    lemmonii (Lemmon's linanthus)
    liniflorus (Flax-flowered linanthus)
    parviflorus (Common linanthus)
    pygmaeus ssp. continentalis (Pygmy linanthus)
Leptosyne
    bigelovii (Bigelow's coreopsis)
    californica (California tickseed)
    gigantea (Giant coreopsis)
    maritima (Sea Dahlia)
Lesquerella
    kingii ssp. bernardina, see Physaria kingii ssp. bernardina
    kingii ssp. kingii, see Physaria kingii ssp. kingii
    tenella, see Physaria tenella
Lessingia
    filaginifolia var. filaginifolia, see Corethrogyne filaginifolia
    glandulifera var. glandulifera (Sticky lessingia)
    glandulifera var. tomentosa (Warner Springs lessingia)
    lemmonii var. lemmonii (Lemmon's lessingia)
    leptoclada (Sierra lessingia)
    tenuis (Spring lessingia)
Leucanthemum vulgare (Ox-eye daisy)*
Lewisia
    nevadensis (Sierra lewisia)
    pygmaea (Dwarf lewisia)
    rediviva (Bitterroot)
Leymus
    cinereus (Great Basin wildrye)
    condensatus (Giant wildrye)
    pacificus (Pacific wildrye)
    triticoides (Creeping wildrye)*
Lilaea scilloides (Flowering quillwort)
Lilium
    humboldtii ssp. ocellatum (Humboldt lily)
    parryi (Lemon lily)
Limnanthes
    alba ssp. parishii (Parish's meadowfoam)
    gracilis ssp. parishii, see Limnanthes alba ssp. parishii
Limonium
    californicum (Sea-lavender)
Limosella acaulis (Stemless mudwort)
Linanthus
    aureus ssp. aureus, see Leptosiphon aureus ssp. aureus
    aureus ssp. decorus, see Leptosiphon aureus ssp. decorus
    breviculus, see Leptosiphon breviculus
    californicus (Prickly phlox)
    campanulatus (Bell gilia)
    ciliatus, see Leptosiphon ciliatus
    concinnus (San Gabriel linanthus)
    demissus (Desert linanthus)
    dianthiflorus (Ground pink)
    dichotomus ssp. dichotomus (Evening snow)
    filiformis (Threadstem gilia)
    floribundus ssp. glaber, see Leptosiphon floribundus ssp. glaber
    floribundus ssp. hallii, see Leptosiphon floribundus ssp. hallii
    jaegeri (San Jacinto prickly phlox)
    jonesii (Jones' linanthus)
    killipii (Baldwin Lake linanthus)
    maculatus (Little San Bernardino Mountains linanthus)
    parryae (Parry's linanthus)
    parviflorus, see Leptosiphon parviflorus
    pungens (Mountain prickly phlox)
    pygmaeus ssp. continentalis, see Leptosiphon pygmaeus ssp. continentalis
Linaria canadensis var. texana, see Nuttallanthus texanus
Linum
    lewisii var. lewisii (Western blue flax)
    usitatissimum (Common flax)*
Listera convallarioides (Twayblade)
Lithocarpus densiflorus var. densiflorus, see Notholithocarpus densiflorus var. densiflorus
Lithophragma
    affine (Woodland star)
    bolanderi (Bolander's woodland stars)
    heterophyllum (Hillside woodland star)
    tenellum (Slender woodland star)
Lobelia
    cardinalis var. pseudosplendens (Scarlet lobelia)
    dunnii var. serrata (Dunn's lobelia)
Lobularia maritima (Sweet alyssum)*
Loeflingia squarrosa (Spreading pygmyleaf)
Loeseliastrum
    matthewsii (Desert calico)
    schottii (Schott's calico)
Logfia
    arizonica (Arizona herba impia)
    depressa (Dwarf filago)
    filaginoides (California filago)
    gallica (Narrow-leaf filago)*
Lolium
    multiflorum (Italian ryegrass)*
    temulentum (Darnel)*
Lomatium
    californicum (California lomatium)
    caruifolium var. caruifolium (Caraway-leaved lomatium)
    dasycarpum ssp. dasycarpum (Woolly lomatium)
    dissectum var. multifidum (Fernleaf lomatium)
    lucidum (Shiny lomatium)
    mohavense (Desert parsley)
    nevadense (Nevada lomatium)
    parryi (Parry's wild parsley)
    utriculatum (Hog fennel)
Lonicera
    hispidula var. vacillans (Hairy honeysuckle)
    interrupta (Chaparral honeysuckle)
    involucrata (Twinberry)
    subspicata var. denudata (Southern honeysuckle)
Lotus  
    argophyllus var. adsurgens, see Acmispon argophyllus var. adsurgens
    argophyllus var. argophyllus, see Acmispon argophyllus var. argophyllus
    argophyllus var. niveus, see Acmispon argophyllus var. niveus
    argyraeus var. argyraeus, see Acmispon argyraeus var. argyraeus
    argyraeus var. multicaulis, see Acmispon argyraeus var. multicaulis
    corniculatus (Bird's-foot trefoil)*
    crassifolius var. crassifolius, see Hosackia crassifolia var. crassifolia
    dendroideus var. dendroideus, see Acmispon dendroideus var. dendroideus
    dendroideus var. veatchii, see Acmispon dendroideus var. veatchii
    denticulatus, see Acmispon denticulatus
    grandiflorus var. grandiflorus, see Acmispon grandiflorus var. grandiflorus
    hamatus, see Acmispon micranthus
    heermannii var. heermannii, see Acmispon heermannii var. heermannii
    humistratus, see Acmispon brachycarpus
    nevadensis var. davidsonii, see Acmispon nevadensis var. davidsonii
    nevadensis var. nevadensis, see Acmispon nevadensis var. nevadensis
    oblongifolius var. oblongifolius, see Hosackia oblongifolia var. oblongifolia
    procumbens var. procumbens, see Acmispon procumbens var. procumbens
    purshianus var. purshianus, see Acmispon americanus var. americanus
    rigidus, see Acmispon rigidus
    salsuginosus var. brevivexillus, see Acmispon maritimus var. brevivexillus
    salsuginosus var. salsuginosus, see Acmispon maritimus var. maritimus
    scoparius var. brevialatus, see Acmispon glaber var. brevialatus
    scoparius var. scoparius, see Acmispon glaber var. glaber
    strigosus, see Acmispon strigosus
    wrangelianus, see Acmispon wrangelianus
Ludwigia peploides (Yellow water-weed)
Lunaria annua (Annual moonwort)*
Lupinus
    albifrons var. albifrons (Silver bush lupine)
    albifrons var. douglasii (Douglas's silver bush lupine)
    andersonii (Anderson's lupine)
    arboreus (Coast bush lupine)
    arbustus (Long-spurred lupine)
    argenteus var. argenteus (Silvery lupine)
    arizonicus (Arizona lupine)
    benthamii (Bentham lupine)
    bicolor (Miniature lupine)
    breweri var. breweri (Brewer's lupine)
    breweri var. grandiflorus (Showy Brewer's lupine)
    chamissonis (Dune lupine)
    concinnus (Bajada lupine)
    elatus (Silky lupine)
    excubitus var. austromontanus (Southern mountain lupine)
    excubitus var. excubitus (Grape soda lupine)
    excubitus var. hallii (Hall's bush lupine)
    excubitus var. johnstonii (Johnston's bush lupine)
    flavoculatus (Yellow-eyed lupine)
    formosus var. formosus (Summer lupine)
    hirsutissimus (Stinging lupine)
    hyacinthinus (San Jacinto lupine)
    latifolius var. latifolius (Broad-leaved lupine)
    latifolius var. parishii (Parish's lupine)
    lepidus var. confertus (Clustered tidy lupine)
    longifolius (Bush lupine)
    luteolus (Pale yellow lupine)
    luteus (European yellow lupine)*
    microcarpus var. densiflorus (White-whorled lupine)
    microcarpus var. horizontalis (Chick lupine)
    microcarpus var. microcarpus (Valley lupine)
    nanus (Sky lupine)
    odoratus (Royal desert lupine)
    peirsonii (Peirson's lupine)
    polyphyllus var. burkei (Meadow lupine)
    shockleyi (Desert lupine)
    sparsiflorus (Coulter's lupine)
    stiversii (Harlequin lupine)
    succulentus (Arroyo lupine)
    truncatus (Collar lupine)
Luzula comosa (Hairy wood rush)
Lycium
    andersonii (Anderson thornbush)
    brevipes var. brevipes (Desert thorn)
    californicum (California boxthorn)
    cooperi (Cooper's boxthorn)
    fremontii (Fremont's thornbush)
Lyonothamnus
    floribundus ssp. aspleniifolius (Fernleaf ironwood)
    floribundus ssp. floribundus (Santa Catalina Island ironwood)
Lyrocarpa coulteri var. palmeri (Coulter's lyrepod)
Lythrum
    californicum (California loosestrife)
    hyssopifolia (Hyssop loosestrife)
Machaeranthera
    arida, see Arida arizonica
    asteroides var. asteroides, see Dieteria asteroides var. asteroides
    asteroides var. lagunensis, see Dieteria asteroides var. lagunensis
    canescens var. canescens, see Dieteria canescens var. canescens
    canescens var. leucanthemifolia, see Dieteria canescens var. leucanthemifolia
    canescens var. ziegleri, see Dieteria canescens var. ziegleri
    gracilis, see Xanthisma gracile
Madia
    elegans (Common madia)
    exigua (Threadstem madia)
    glomerata (Mountain madia)
    gracilis (Sticky madia)
    minima, see Hemizonella minima
Maianthemum
    racemosum (False solomon's seal)
    stellatum (Star-flowered false solomon's seal)
Malacothamnus
    aboriginum (Indian Valley bush mallow)
    clementinus (San Clemente Island bush mallow)
    densiflorus (Yellow-stemmed bush mallow)
    fasciculatus (Bush mallow)
    fremontii (Fremont's bush mallow)
    marrubioides (Pink-flowered bush mallow)
Malacothrix
    californica (California malacothrix)
    clevelandii (Annual malacothrix)
    coulteri (Snake's head)
    glabrata (Desert dandelion)
    incana (Dunedelion)
    saxatilis var. implicata (Cliff malacothrix)
    saxatilis var. tenuifolia (Short-leaved cliff aster)
    sonchoides (Yellow saucers)
Malcolmia africana (African mustard)*
Malephora crocea (Red iceplant)*
Malosma laurina (Laurel sumac)
Malperia tenuis (Brown turbans)
Malva
    nicaeensis (Bull mallow)*
    parviflora (Cheeseweed)*
Malvella leprosa (Alkali mallow)
Mammillaria
    dioica (Fishhook cactus)
    tetrancistra (Fishhook cactus)
Marah
    fabacea (California man-root)
    macrocarpa var. macrocarpa (Wild cucumber)
    macrocarpa var. major (Island wild cucumber)
Marina
    orcuttii var. orcuttii (California marina)
    parryi (Parry's marina)
Marrubium vulgare (Horehound)*
Marsilea vestita ssp. vestita (Clover fern)
Matelea parvifolia (Spearleaf)
Matricaria matricarioides (Pineapple weed)*
Matthiola incana (Garden stock)*
Maurandella antirrhiniflora (Violet twining snapdragon)
Maurandya antirrhiniflora ssp. antirrhiniflora, see Maurandella antirrhiniflora
Meconella denticulata (Small-flowered meconella)
Medicago
    lupulina (Black medick)*
    polymorpha (California bur-clover)*
    sativa (Alfalfa)*
Melica
    frutescens (Tall melica)
    imperfecta (Coast range melic)
Melilotus
    albus (White sweetclover)*
    indicus (Sourclover)*
    officinalis (Yellow sweetclover)*
Menodora
    scabra (Rough menodora)
    spinescens (Spiny menodora)
Mentha
    arvensis (Field mint)
    spicata var. spicata (Spearmint)*
    Xpiperita var. citrata (Bergamot mint)*
Mentzelia
    affinis (Yellow comet)
    albicaulis (Whitestem blazing star)
    congesta (Clustered blazing star)
    dispersa (Bushy blazing star)
    hirsutissima (Hairy blazing star)
    involucrata (Sand blazing star)
    laevicaulis (Giant blazing star)
    lindleyi (Lindley's blazing star)
    micrantha (Stickleaf)
    montana (Mountain blazing star)
    multiflora var. longiloba (Yerba amarilla)
    obscura (Pacific blazing star)
    oreophila (Inyo blazing star)
    polita (Polished blazing star)
    reflexa (Reflexed blazing star)
    veatchiana (Veatch's blazing star)
Mesembryanthemum
    crystallinum (Crystalline iceplant)*
    nodiflorum (Slender-leaved iceplant)*
Micropus californicus var. californicus (Slender cottonweed)
Microseris douglasii ssp. douglasii (Douglas's microseris)
Microsteris gracilis (Common slender phlox)
Mimulus
    androsaceus (Rockjasmine monkeyflower)
    aurantiacus (Bush or sticky monkeyflower)
    bigelovii var. bigelovii (Bigelow's monkeyflower)
    bigelovii var. cuspidatus (Bigelow's monkeyflower)
    bolanderi (Bolander's monkeyflower)
    brevipes (Yellow monkeyflower)
    breweri (Brewer's monkeyflower)
    cardinalis (Scarlet monkeyflower)
    clevelandii (Cleveland's bush monkeyflower)
    constrictus (Dense-fruited monkeyflower)
    exiguus (San Bernardino Mountains monkeyflower)
    flemingii (Island bush monkeyflower)
    floribundus (Many-flowered monkeyflower)
    fremontii var. fremontii (Fremont's monkeyflower)
    guttatus (Creek monkeyflower)
    johnstonii (Johnston's monkeyflower)
    moschatus (Musk monkeyflower)
    palmeri (Palmer's monkeyflower)
    parishii (Parish's monkeyflower)
    pilosus (Downy monkeyflower)
    primuloides ssp. primuloides (Primrose monkeyflower)
    purpureus (Purple monkeyflower)
    rupicola (Death Valley monkeyflower)
    rubellus (Red-stemmed monkeyflower)
    shevockii (Kelso Creek monkeyflower)
    suksdorfii (Suksdorf's monkeyflower)
    tilingii (Tiling's monkeyflower)
Minuartia
    douglasii (Douglas's stitchwort)
    nuttallii var. gracilis (Brittle sandwort)
    pusilla (Annual sandwort)
Mirabilis
    albida (Dwarf four o'clock)
    bigelovii var. bigelovii, see Mirabilis laevis var. villosa
    bigelovii var. retrorsa, see Mirabilis laevis var. retrorsa
    coccinea (Red four o'clock)
    jalapa (Cultivated four o'clock)*
    laevis var. crassifolia (Wishbone bush)
    laevis var. retrorsa (Retrorse desert four o'clock)
    laevis var. villosa (Bigelow's desert four o'clock)
    multiflora var. pubescens (Giant four o'clock)
    pumila, see Mirabilis albida
    tenuiloba (Slender-lobed four o'clock)
Mohavea
    breviflora (Lesser mohavea)
    confertiflora (Ghost flower)
Mollugo cerviana (Threadstem carpet-weed)*
Monanthochloe littoralis (Shoregrass)
Monarda pectinata (Bee balm)
Monardella
    australis ssp. australis (Southern monardella)
    australis ssp. cinerea (Gray monardella)
    breweri ssp. lanceolata (Mustang mint)
    exilis (Desert pennyroyal)
    hypoleuca ssp. hypoleuca (White-leaf monardella)
    lanceolata, see Monardella breweri ssp. lanceolata
    linoides ssp. erecta (Flax-leaved monardella)
    linoides ssp. linoides (Narrow-leaf monardella)
    linoides ssp. oblonga (Flax-like monardella)
    linoides ssp. viminea, see Monardella viminea
    macrantha ssp. hallii (Red monardella)
    nana ssp. arida (Desert monardella) * These four ssp. are Monardella nana in JM2
    nana ssp. leptosiphon (San Felipe monardella) * These four ssp. are Monardella nana in JM2
    nana ssp. nana (Little monardella) * These four ssp. are Monardella nana in JM2
    nana ssp. tenuiflora (Short-flowered monardella) * These four ssp. are Monardella nana in JM2
    robisonii (Rock pennyroyal)
    viminea (Willowy monardella)
Monolepis nuttalliana (Nuttall's poverty weed)
Monolopia lanceolata (Monolopia)
Monoptilon
    bellidiforme (Daisy desertstar)
    bellioides (Desert stars)
Montia chamissoi (Toad lily)
Morella californica (California wax-myrtle)
Mortonia utahensis (Mortonia)
Muhlenbergia
    filiformis (Pullup muhly)
    porteri (Bush muhly)
    richardsonis (Mat muhly)
    rigens (Deergrass)
Muilla
    clevelandii (Cleveland's muilla)
    maritima (Common muilla)
Myrica californica, see Morella californica
Myriophyllum sibiricum (Siberian milfoil)
Nama
    californicum (California fiddleleaf)
    demissum var. covillei (Purple mat)
    demissum var. demissum (Purple mat)
    pusillum (Small-leaved nama)
    rothrockii (Rothrock's nama)
    stenocarpum (Mud nama)
Nassella
    cernua (Nodding needlegrass)
    lepida (Foothill needlegrass)
    pulchra (Purple needlegrass)
Navarretia
    atractyloides (Hollyleaf navarretia)
    breweri (Brewer's navarretia)
    fossalis (Spreading navarretia)
    hamata ssp. hamata (Hooked navarretia)
    ojaiensis (Ojai navarretia)
    peninsularis (Baja navarretia)
    prostrata (Prostrate navarretia)
Nemacladus
    glanduliferus (Glandular threadplant)
    glanduliferus var. glanduliferus, see Nemacladus glanduliferus
    glanduliferus var. orientalis, see Nemacladus orientalis
    longiflorus var. breviflorus (Long-flowered threadplant)
    longiflorus var. longiflorus (Long-flowered threadplant)
    orientalis (Eastern threadplant)
    pinnatifidus (Comb-leaved threadplant)
    ramosissimus (Smallflower threadplant)
    rubescens (Desert threadplant)
    sigmoideus (Sigmoid threadplant)
    tenuis var. tenuis (Slender threadplant)
Nemophila
    maculata (Fivespot)
    menziesii var. integrifolia (Baby blue eyes)
    menziesii var. menziesii (Baby blue eyes)
    pedunculata (Meadow nemophila)
    pulchella var. pulchella (Eastwood's baby blue eyes)
    spatulata (Sierra nemophila)
Nicolletia occidentalis (Hole-in-the-sand plant)
Nicotiana
    attenuata (Coyote tobacco)
    glauca (Tree tobacco)*
    obtusifolia (Desert tobacco)
    quadrivalvis (Indian tobacco)
Nolina
    bigelovii (Beargrass)
    cismontana (Chaparral beargrass)
    interrata (Dehesa nolina)
    parryi (Parry's nolina)
Notholaena californica (California cloak fern)
Notholithocarpus densiflorus var. densiflorus (Tanbark oak)
Nuttallanthus texanus (Blue toadflax)
Oemleria cerasiformis (Oso berry)
Oenanthe sarmentosa (Water-parsley)
Oenothera
    caespitosa ssp. marginata (Tufted evening primrose)
    californica ssp. avita (Desert evening primrose)
    californica ssp. californica (California evening primrose)
    californica ssp. eurekensis (Eureka Dunes evening primrose)
    cavernae (Cave-dwelling evening primrose)
    deltoides ssp. deltoides (Dune primrose)
    elata ssp. hirsutissima (Hairy evening primrose)
    elata ssp. hookeri (Hooker's evening primrose)
    primiveris ssp. bufonis (Large yellow primrose)
    rosea (Rose evening primrose)*
    sinuosa (Wavyleaf bee blossom)*
    suffrutescens (Scarlet gaura)
Oligomeris linifolia (Oligomeris)
Olneya tesota (Desert ironwood)
Oncosiphon piluliferum (Globe chamomile)*
Ophioglossum californicum (California adder's-tongue)
Opuntia
    acanthocarpa var. coloradensis, see Cylindropuntia acanthocarpa var. coloradensis
    basilaris var. basilaris (Beavertail cactus)
    basilaris var. brachyclada (Short-joint beavertail cactus)
    bigelovii, see Cylindropuntia bigelovii
    chlorotica (Pancake prickly-pear)
    echinocarpa, see Cylindropuntia echinocarpa
    erinacea var. erinacea, see Opuntia polyacantha var. erinacea
    ficus-indica (Mission cactus)*
    fosbergii (Fosberg's cholla)
    littoralis (Coast prickly-pear)
    occidentalis (Western prickly-pear)
    oricola (Chaparral prickly-pear)
    parishii (Mat cholla)
    parryi var. parryi, see Cylindropuntia californica var. parkeri
    phaeacantha (Desert prickly-pear)
    polyacantha var. erinacea (Mojave prickly-pear)
    prolifera, see Cylindropuntia prolifera
    ramosissima, see Cylindropuntia ramosissima
    vaseyi (Vasey's prickly-pear)
    wolfii, see Cylindropuntia wolfii
Oreonana vestita (Woolly mountain parsley)
Oreostemma alpigenum var. andersonii (Alpine aster)
Ornithostaphylos oppositifolia (Baja birdbush)
Orobanche
    bulbosa (Chaparral broom-rape)
    californica ssp. feudgei (California broom-rape)
    cooperi (Cooper's broom-rape)
    fasciculata (Clustered broom-rape)
    parishii ssp. brachyloba (Short-lobed broom-rape)
    parishii ssp. parishii (Parish's broom-rape)
    uniflora (Naked broom-rape)
    valida ssp. valida (Rock Creek broom-rape)
    vallicola (Valley broom-rape)
Orthilia secunda (One-sided wintergreen)
Osmadenia tenella (Three-spot)
Osmorhiza
    berteroi (Mountain sweet-cicely)
    brachypoda (Sweet-cicely)
    chilensis, see Osmorhiza berteroi
Osteospermum ecklonis (African daisy)*
Oxalis
    albicans ssp. californica, see Oxalis californica
    californica (Wild oxalis)
    corniculata (Creeping wood-sorrel)*
    pes-caprae (Bermuda buttercup)*
    pilosa (Hairy wood sorrel)
Oxypolis occidentalis (Western cowbane)
Oxystylis lutea (False-clover)
Oxytheca
    caryophylloides, see Sidotheca caryophylloides
    emarginata, see Sidotheca emarginata
    parishii var. cienegensis, see Acanthoscyphus parishii var. cienegensis
    parishii var. goodmaniana, see Acanthoscyphus parishii var. goodmaniana
    parishii var. parishii, see Acanthoscyphus parishii var. parishii
    perfoliata (Roundleaf oxytheca)
    trilobata, see Sidotheca trilobata
Oxytropis oreophila var. oreophila (Mountain oxytrope)
Packera
    bernardina (San Bernardino ragwort)
    ionophylla (Tehachapi ragwort)
    multilobata (Basin butterweed)
Paeonia californica (Wild peony)
Palafoxia
    arida var. arida (Spanish needles)
    arida var. gigantea (Giant Spanish needles)
Panicum urvilleanum (Desert panic grass)
Papaver californicum (Fire poppy)
Parapholis incurva (Curved sicklegrass)*
Parietaria
    hespera var. hespera (Pellitory)
    pensylvanica (Pennsylvania pellitory)
Parkinsonia
    florida (Palo verde)
    florida fruit (Palo verde)
    microphylla (Littleleaf palo verde)
Parnassia
    californica, see Parnassia palustris
    palustris (Grass-of-parnassus)
Paspalum
    dilatatum (Dallis grass)*
    distichum (Knot grass)
Pectis papposa var. papposa (Chinchweed)
Pectocarya
    heterocarpa (Hairy-leaved pectocarya)
    linearis ssp. ferocula (Slender pectocarya)
    penicillata (Winged pectocarya)
    platycarpa (Broad-fruited pectocarya)
    recurvata (Curvenut pectocarya)
    setosa (Bristly pectocarya)
Pedicularis
    densiflora (Indian warrior)
    semibarbata (Pine lousewort)
Pellaea
    andromedifolia (Coffee fern)
    mucronata var. californica (California cliff brake)
    mucronata var. mucronata (Bird's-foot fern)
    truncata (Cliff brake)
Pennisetum
    clandestinum (Kikuyu grass)*
    setaceum (Fountaingrass)*
Penstemon
    caesius (San Bernardino beardtongue)
    calcareus (Limestone beardtongue)
    californicus (California beardtongue)
    centranthifolius (Scarlet bugler)
    clevelandii var. clevelandii (Cleveland's beardtongue)
    clevelandii var. connatus (San Jacinto beardtongue)
    eatonii var. undosus (Firecracker penstemon)
    floridus var. austinii (Austin's beardtongue)
    fruticiformis var. fruticiformis (Desert beardtongue)
    grinnellii var. grinnellii (Grinnell's penstemon)
    grinnellii var. scrophularioides (Grinnell's penstemon)
    heterophyllus var. australis (Foothill penstemon)
    heterophyllus var. heterophyllus (Foothill penstemon)
    labrosus (San Gabriel beardtongue)
    labrosus (yellow form) (San Gabriel beardtongue)
    laetus var. laetus (Mountain blue penstemon)
    newberryi var. newberryi (Pride of the mountains)
    palmeri var. palmeri (Palmer's penstemon)
    pseudospectabilis (Desert penstemon)
    rostriflorus (Beaked penstemon)
    speciosus (Royal penstemon)
    spectabilis var. spectabilis (Showy penstemon)
    spectabilis var. subviscosus (Showy penstemon)
    stephensii (Stephens' beardtongue)
    thurberi (Thurber penstemon)
    utahensis (Utah penstemon)
Pentachaeta
    aurea ssp. allenii (Allen's daisy)
    aurea ssp. aurea (Golden-rayed pentachaeta)
    lyonii (Lyon's pentachaeta)
Pentagramma
    triangularis ssp. triangularis (Goldback fern)
    triangularis ssp. viscosa (Silverback fern)
Perideridia
    parishii ssp. latifolia (Wide-leaved Parish's yampah)
    parishii ssp. parishii (Parish's yampah)
Peritoma arborea (Bladderpod)
Perityle emoryi (Rock daisy)
Petalonyx
    nitidus (Shinyleaf sandpaper plant)
    thurberi (Sandpaper plant)
Petrophyton caespitosum (Rock spiraea)
Petrorhagia dubia (Hairypink)*
Petunia parviflora (Seaside petunia)
Peucephyllum schottii (Desert-fir)
Phacelia
    affinis (Limestone phacelia)
    anelsonii (Aven Nelson's phacelia)
    austromontana (Southern mountain phacelia)
    brachyloba (Yellow-throated phacelia)
    calthifolia (Caltha-leaved phacelia)
    campanularia ssp. campanularia (Desert bluebells)
    campanularia ssp. vasiformis (Desert bluebells)
    cicutaria var. cicutaria (Caterpillar phacelia)
    cicutaria var. hispida (Caterpillar phacelia)
    cicutaria var. hubbyi, see Phacelia hubbyi
    ciliata (Great Valley phacelia)
    crenulata var. ambigua (Notchleaf phacelia)
    crenulata var. crenulata (Notchleaf phacelia)
    crenulata var. minutiflora (Smallflower notchleaf phacelia)
    cryptantha (Hiddenflower phacelia)
    curvipes (Curved-stem phacelia)
    davidsonii (Davidson's phacelia)
    distans (Common phacelia)
    douglasii (Douglas phacelia)
    egena (Rock phacelia)
    exilis (Lavender windows)
    fremontii (Fremont's phacelia)
    grandiflora (Large-flowered phacelia)
    hastata ssp. hastata (Timberline phacelia)
    hubbyi (Hubby's caterpillar phacelia)
    humilis var. dudleyi (Low phacelia)
    imbricata ssp. imbricata (Mountain phacelia)
    imbricata ssp. patula (Imbricate phacelia)
    insularis var. insularis (Northern Channel Islands phacelia)
    ivesiana (Ives' phacelia)
    longipes (Longstalk phacelia)
    minor (Canterbury bells)
    mohavensis (Mojave phacelia)
    mutabilis (Changeable phacelia)
    nashiana (Charlotte's phacelia)
    neglecta (Alkali phacelia)
    pachyphylla (Thick-leaved phacelia)
    parryi (Parry's phacelia)
    pedicellata (Pedicellate phacelia)
    perityloides var. perityloides (Panamint phacelia)
    ramosissima var. latifolia (Branching phacelia) * These two vars. are Phacelia ramosissima in JM2
    ramossisima var. ramossisima (Branching phacelia) * These two vars. are Phacelia ramosissima in JM2
    rotundifolia (Round-leaved phacelia)
    tanacetifolia (Tansy phacelia)
    vallis-mortae (Death Valley phacelia)
    viscida (Sticky phacelia)
Phalaris aquatica (Harding grass)*
Philadelphus microphyllus (Little-leaved mock orange)
Phleum alpinum (Mountain timothy)
Phlox
    austromontana (Southern mountain phlox)
    condensata (Condensed phlox)
    diffusa (Spreading phlox)
    dolichantha (Big Bear Valley phlox)
    gracilis, see Microsteris gracilis
    stansburyi (Stansbury phlox)
Pholisma
    arenarium (Scaly-stemmed sand plant)
    sonorae (Sand food)
Pholistoma
    auritum var. auritum (Fiesta flower)
    membranaceum (White fiesta flower)
Phoradendron
    bolleanum (Fir mistletoe)
    californicum (Desert mistletoe)
    juniperinum (Juniper mistletoe)
    libocedri (Incense-cedar mistletoe)
    macrophyllum (Big-leaf mistletoe)
    pauciflorum, see Phoradendron bolleanum
    villosum (Oak mistletoe)
Phragmites australis (Common reed)
Phyllodoce breweri (Mountain heather)
Physalis
    crassifolia (Thick-leaved ground-cherry)
    hederifolia var. fendleri (Fendler's ground-cherry)
    lobata (Lobed ground-cherry)
Physaria
    kingii ssp. bernardina (San Bernardino Mountains bladderpod)
    kingii ssp. kingii (King's bladderpod)
    tenella (Palmer beadpod)
Physocarpus capitatus (Pacific ninebark)
Phytolacca americana (Pokeweed)*
Pickeringia
    montana var. montana (Chaparral pea)
    montana var. tomentosa (Woolly chaparral pea)
Picris echioides, see Helminthotheca echioides
Pilostyles thurberi (Thurber's stemsucker)
Pinus
    attenuata (Knobcone pine)
    contorta ssp. murrayana (Lodgepole pine)
    coulteri (Coulter pine)
    flexilis (Limber pine)
    halepensis (Aleppo pine)*
    jeffreyi (Jeffrey pine)
    lambertiana (Sugar pine)
    longaeva (Bristlecone pine)
    monophylla (Singleleaf pinyon pine)
    muricata (Bishop pine)
    ponderosa (Yellow pine)
    quadrifolia (Four-needle pinyon pine)
    sabiniana (Gray pine)
    torreyana (Torrey pine)
Piperia
    cooperi (Rein orchid)
    elongata (Dense-flowered rein orchid)
    transversa (Royal rein orchid)
    unalascensis (Alaska rein orchid)
Piptatherum miliaceum (Smilo grass)*
Plagiobothrys
    acanthocarpus (Adobe popcorn flower)
    arizonicus (Arizona popcorn flower)
    canescens (Valley popcorn flower)
    collinus var. fulvescens (California popcorn flower)
    fulvus (Tawny popcorn flower)
    hispidulus (Harsh popcorn flower)
    jonesii (Mojave popcorn flower)
    nothofulvus (Rusty-haired popcorn flower)
    tenellus (Slender popcorn flower)
    undulatus (Hooked popcorn flower)
Plantago
    arenaria (Sand plantain)*
    coronopus (Cut-leaf plantain)*
    elongata (Longleaf plantain)
    erecta (California plantain)
    lanceolata (English plantain)*
    major (Broad-leaf plantain)*
    ovata (Woolly plantain)
    patagonica (Patagonia plantain)
Platanthera
    dilatata var. leucostachys (White-flowered bog orchid)
    leucostachys, see Platanthera dilatata var. leucostachys
    sparsiflora (Sparse-flowered bog orchid)
Platanus racemosa (Western sycamore)
Platystemon californicus (Cream cups)
Plectritis ciliosa ssp. insignis (Long-spurred plectritis)
Pleiacanthus spinosus (Thorny skeleton-plant)
Pleuraphis rigida, see Hilaria rigida
Pleurocoronis pluriseta (Arrowleaf)
Pluchea
    odorata (Salt marsh fleabane)
    sericea (Arrow weed)
Poa
    atropurpurea (San Bernardino bluegrass)
    bulbosa (Bulbous bluegrass)*
    douglasii (Sand-dune bluegrass)
    fendleriana ssp. longiligula (Fendler's bluegrass)
    infirma (Weak bluegrass)*
    pratensis ssp. pratensis (Kentucky bluegrass)*
    secunda ssp. juncifolia (Rush bluegrass)
    secunda ssp. secunda (One-sided bluegrass)
Pogogyne nudiuscula (Otay Mesa mint)
Polemonium occidentale ssp. occidentale (Western sky pilot)
Polycarpon tetraphyllum (Four-leaf allseed)*
Polygala cornuta var. fishiae (Fish's milkwort)
Polygonum
    amphibium var. emersum (Swamp knotweed)
    arenastrum, see Polygonum aviculare ssp. depressum
    aviculare ssp. depressum (Common knotweed)*
    bistortoides, see Bistorta bistortoides
    capitatum (Himalayan smartweed)*
    douglasii ssp. douglasii (Douglas's knotweed)
    douglasii ssp. johnstonii (Douglas's knotweed)
    lapathifolium (Willow smartweed)
    punctatum (Water smartweed)
Polypodium
    californicum (California polypody)
    hesperium (Western polypody)
Polypogon
    interruptus (Ditch beard grass)*
    monspeliensis (Rabbitsfoot grass)*
    viridis (Green bentgrass)*
Polystichum
    imbricans ssp. curtum (Cliff sword fern)
    munitum (Western sword fern)
    scopulinum (Mountain holly fern)
Populus
    balsamifera ssp. trichocarpa (Black cottonwood)
    fremontii ssp. fremontii (Fremont's cottonwood)
    tremuloides (Quaking aspen)
Porophyllum gracile (Slender poreleaf)
Portulaca
    halimoides (Desert portulaca)
    oleracea (Purslane)*
Potamogeton diversifolius (Diverse-leaved pondweed)
Potentilla
    anserina ssp. anserina (Silverleaf cinquefoil)
    anserina ssp. pacifica (Silverweed)
    biennis (Biennial cinquefoil)
    glandulosa ssp. ewanii, see Drymocallis cuneifolia var. ewanii
    glandulosa ssp. glandulosa in part, see Drymocallis glandulosa var. wrangelliana (SoCO)
    glandulosa ssp. nevadensis, see Drymocallis lactea var. lactea
    glandulosa ssp. reflexa in part, see Drymocallis glandulosa var. reflexa (TR,PR)
    glandulosa ssp. reflexa in part, see Drymocallis glandulosa var. viscida (TR,PR)
    gracilis var. fastigiata (Slender cinquefoil)
    norvegica (Norwegian cinquefoil)*
    wheeleri (Wheeler's cinquefoil)
Prenanthella exigua (Bright white)
Prosopis
    glandulosa var. torreyana (Honey mesquite)
    pubescens (Screwbean mesquite)
Prunella vulgaris var. lanceolata (Self-heal)
Prunus
    andersonii (Desert peach)
    emarginata (Bitter cherry)
    eremophila (Desert prunus)
    fasciculata var. fasciculata (Desert almond)
    fremontii (Desert apricot)
    ilicifolia ssp. ilicifolia (Hollyleaf cherry)
    ilicifolia ssp. ilicifolia fruit (Hollyleaf cherry)
    ilicifolia ssp. lyonii (Catalina cherry)
    virginiana var. demissus (Western chokecherry)
Psathyrotes
    annua (Fan leaf)
    ramosissima (Turtleback)
Pseudognaphalium
    beneolens (Fragrant everlasting)
    biolettii (Two-tone everlasting)
    californicum (California everlasting)
    luteoalbum (Weedy cudweed)*
    microcephalum (Feltleaf everlasting)
    ramosissimum (Pink cudweed)
    stramineum (Cotton-batting plant)
    thermale (Slender everlasting)
Pseudostellaria jamesiana (Sticky starwort)
Pseudotsuga macrocarpa (Big-cone spruce)
Psilocarphus
    brevissimus var. brevissimus (Dwarf woollyheads)
    tenellus var. tenellus (Slender woollyheads)
Psilostrophe cooperi (Paperflower)
Psorothamnus
    arborescens var. minutifolius (Little-leaved Mojave indigo bush)
    arborescens var. simplicifolius (California indigo bush)
    emoryi (Emory indigo bush)
    polydenius (Dotted indigo bush)
    schottii (Schott's indigo bush)
    spinosus (Smoke tree)
Pteridium aquilinum var. pubescens (Bracken fern)
Pteris vittata (Ladder brake)*
Pterospora andromedea (Pinedrops)
Pterostegia drymarioides (Threadstem)
Pulicaria paludosa (Pulicaria)*
Purshia
    mexicana var. stansburyana (Cliff rose)
    tridentata var. glandulosa (Desert bitterbrush)
Pycnanthemum californicum (Mountain mint)
Pyrola
    asarifolia ssp. asarifolia (Bog wintergreen)
    picta (White-veined wintergreen)
Pyrrocoma uniflora var. gossypina (Bear Valley pyrrocoma)
Quercus
    acutidens (Torrey's scrub oak)
    agrifolia var. agrifolia (Coast live oak)
    agrifolia var. oxyadenia (Southern coast live oak)
    berberidifolia (Inland scrub oak)
    chrysolepis (Canyon live oak)
    cornelius-mulleri (Muller's oak)
    douglasii (Blue oak)
    dumosa (Coastal scrub oak)
    durata var. gabrielensis (San Gabriel Mountains leather oak)
    engelmannii (Engelmann oak)
    garryana var. breweri (Brewer's oak)
    john-tuckeri (Desert scrub oak)
    kelloggii (California black oak)
    pacifica (Channel Island scrub oak)
    palmeri (Palmer's oak)
    tomentella (Island oak)
    turbinella (Shrub live oak)
    wislizeni var. frutescens (Shrubby interior live oak)
    wislizeni var. wislizeni (Interior live oak)
Rafinesquia
    californica (California chicory)
    neomexicana (Desert chicory)
Raillardella argentea (Silky raillardella)
Ranunculus
    alismifolius var. alismellus (Small water-plantain buttercup)
    aquatilis var. capillaceus (Water buttercup)
    californicus var. californicus (California buttercup)
    cymbalaria var. saximontanus (Rocky Mountain buttercup)
    eschscholtzii var. oxynotus (Eschscholtz's buttercup)
    hebecarpus (Delicate buttercup)
    occidentalis (Western buttercup)
    sceleratus (Cursed crowfoot)
    testiculatus (Tubercled crowfoot)*
Raphanus sativus (Wild radish)*
Rhamnus
    crocea (Littleleaf redberry)
    ilicifolia (Hollyleaf redberry)
    pirifolia (Island redberry)
Rhododendron occidentale (Western azalea)
Rhus
    aromatica (Skunkbush)
    integrifolia (Lemonade berry)
    ovata (Sugar bush)
    trilobata, see Rhus aromatica
Ribes
    amarum (Bitter gooseberry)
    aureum var. gracillimum (Golden currant)
    californicum var. hesperium (Hillside gooseberry)
    cereum var. cereum (Wax currant)
    indecorum (White-flowering currant)
    lasianthum (Alpine gooseberry)
    malvaceum var. viridifolium (Chaparral currant)
    montigenum (Mountain gooseberry)
    nevadense (Mountain pink currant)
    quercetorum (Oak gooseberry)
    roezlii var. roezlii (Sierra gooseberry)
    speciosum (Fuchsia-flowered gooseberry)
    thacherianum (Santa Cruz Island gooseberry)
    velutinum (Desert gooseberry)
    viburnifolium (Evergreen currant)
Ricinus communis (Castor bean)*
Rigiopappus leptocladus (Wireweed)
Robinia
    neomexicana (Desert locust)
    pseudoacacia (Black locust)*
Romneya
    coulteri (Matilija poppy)
    trichocalyx (Bristly matilija poppy)
Rorippa
    curvisiliqua (Curvepod yellowcress)
    nasturtium-aquaticum, see Nasturtium officinale
    officinale (Watercress)*
    palustris var. occidentalis (Western bog yellow-cress)
Rosa
    californica (Wild rose)
    gymnocarpa (Wood rose)
    minutifolia (Small-leaved rose)
    woodsii var. ultramontana (Interior rose)
Rubus
    discolor (Himalaya-berry)*
    leucodermis (Western raspberry)
    parviflorus (Thimbleberry)
    ursinus (California blackberry)
    ursinus fruit (California blackberry)
Rumex
    acetosella (Sheep sorrel)*    
    conglomeratus (Whorled dock)*
    crispus (Curly dock)*
    hymenosepalus (Wild rhubarb)
    pulcher (Fiddle dock)*
    salicifolius var. denticulatus (Willow-leaved dock)
Rupertia
    physodes (California tea)
    rigida (Parish's psoralea)
Sagina
    apetala (Dwarf pearlwort)*
    decumbens ssp. occidentalis (Western pearlwort)
    saginoides (Alpine pearlwort)
Salazaria mexicana, see Scutellaria mexicana
Salicornia
    subterminalis (Glasswort)
    virginica (Virginia pickleweed)
Salix
    exigua (Sandbar willow)
    gooddingii (Goodding's black willow)
    laevigata (Red willow)
    lasiolepis (Arroyo willow)
    lemmonii (Lemmon's willow)
    lucida ssp. lasiandra (Shining willow)
    scouleriana (Scouler's willow)
Salsola
    paulsenii (Barbwire Russian thistle)*
    tragus (Russian thistle)*
Saltugilia
    australis (Southern gilia)
    caruifolia (Caraway-leaved gilia)
    splendens ssp. grantii (Grant's gilia)
    splendens ssp. splendens (Splendid gilia)
Salvia
    apiana (White sage)
    brandegeei (Brandegee's sage)
    carduacea (Thistle sage)
    clevelandii (Cleveland sage)
    columbariae (Chia)
    dorrii var. dorrii (Blue sage)
    dorrii var. pilosa (Blue sage)
    eremostachya (Desert sage)
    funerea (Death Valley sage)
    leucophylla (Purple sage)
    mellifera (Black sage)
    munzii (Munz's sage)
    pachyphylla (Rose sage)
    sonomensis (Creeping sage)
    spathacea (Crimson pitcher sage)
    vaseyi (Vasey's sage)
Sambucus
    mexicana, see Sambucus nigra ssp. caerulea
    nigra ssp. caerulea (Mexican elderberry)
    racemosa var. racemosa (Red elderberry)
Samolus parviflorus (Water-pimpernel)
Sanicula
    arguta (Snakeroot)
    bipinnata (Poison sanicle)
    bipinnatifida (Purple sanicle)
    crassicaulis (Pacific sanicle)
    graveolens (Sierra sanicle)
    tuberosa (Turkey pea)
Sanvitalia abertii (Abert's sanvitalia)
Sarcobatus vermiculatus (Greasewood)
Sarcodes sanguinea (Snow plant)
Sarcostemma
    cynanchoides ssp. hartwegii, see Funastrum cynanchoides var. hartwegii
    hirtellum, see Funastrum hirtellum
Satureja
    chandleri, see Clinopodium chandleri
    douglasii, see Clinopodium mimuloides
    mimuloides, see Clinopodium mimuloides
Saxifraga californica (California saxifrage)
Schinus
    molle (Peruvian pepper)*
    molle fruit (Peruvian pepper)*
    terebinthifolius (Brazilian pepper)*
Schismus barbatus (Common Mediterranean grass)*
Schkuhria multiflora var. multiflora (Many-flowered bahia)
Schoenoplectus
    americanus (American bulrush)
    californicus (California bulrush)
Scirpus
    americanus, see Schoenoplectus americanus
    californicus, see Schoenoplectus californicus
    maritimus, see Bolboschoenus maritimus
    microcarpus (Panicled bulrush)
Scopulophila rixfordii (Rixford's rockwort)
Scrophularia
    californica (California figwort)
    desertorum (Desert figwort)
Scutellaria
    bolanderi ssp. austromontana (Southern skullcap)
    mexicana (Paperbag bush)
    siphocampyloides (Grayleaf skullcap)
    tuberosa (Common skullcap)
Secale cereale (Cereal rye)*
Sedum
    niveum (Davidson's stonecrop)
    spathulifolium (Broad-leaf stonecrop)
Selaginella
    asprella (Bluish spike-moss)
    bigelovii (Bigelow's spike-moss)
    cinerascens (Ashy spike-moss)
    eremophila (Desert spike-moss)
    hansenii (Hansen's spike-moss)
    watsonii (Watson's spike-moss)
Senecio
    bernardinus, see Packera bernardina
    californicus (California groundsel)
    flaccidus var. douglasii (Bush senecio)
    flaccidus var. monoensis (Mono groundsel)
    fremontii var. occidentalis (Dwarf mountain ragwort)
    ionophyllus, see Packera ionophylla
    mohavensis (Mojave ragwort)
    multilobatus, see Packera multilobata
    spartioides (Broom groundsel)
    triangularis (Arrowleaf butterweed)
    vulgaris (Common groundsel)*
Senegalia greggii (Catclaw acacia)
Senna
    armata (Desert senna)
    covesii (Coues' senna)
Sequoiadendron giganteum (Giant sequoia)*
Shepherdia argentea (Buffalo-berry)
Sherardia arvensis (Field madder)*
Sibbaldia procumbens (Sibbaldia)
Sidalcea
    malviflora ssp. dolosa (Dwarf checkerbloom)
    malviflora ssp. malviflora (Island checkerbloom)
    malviflora ssp. sparsifolia, see Sidalcea sparsifolia
    pedata (Big Bear checkerbloom)
    sparsifolia (Few-leaved checkerbloom)
Sidotheca
    caryophylloides (Chickweed oxytheca)
    emarginata (Whitemargin oxytheca)
    trilobata (Threelobe oxytheca)
Silene
    antirrhina (Sleepy catchfly)
    gallica (Windmill pink)*
    laciniata ssp. laciniata (Mexican pink)
    laciniata ssp. major, see Silene laciniata ssp. laciniata
    lemmonii (Lemmon's catchfly)
    menziesii (Menzies' campion)
    multinervia (Many-nerved catchfly)
    parishii (Parish's catchfly)
    verecunda (White catchfly)
Silybum marianum (Milk thistle)*
Simmondsia
    chinensis (male flowers) (Jojoba)
    chinensis (female flowers) (Jojoba)
Sisymbrium
    altissimum (Tumble mustard)*
    irio (London rocket)*
    officinale (Hedge mustard)*
    orientale (Oriental mustard)*
Sisyrinchium
    bellum (Blue-eyed grass)
    elmeri (Yellow-eyed grass)
    idahoense var. occidentale (Idaho blue-eyed grass)
Smilacina
    racemosa, see Maianthemum racemosum
    stellata, see Maianthemum stellatum
Solanum
    americanum (Small-flowered nightshade)
    douglasii (White nightshade)
    elaeagnifolium (Silverleaf horse-nettle)*
    parishii (Parish's nightshade)
    umbelliferum (Blue-witch nightshade)
    xanti (Purple nightshade)
    xanti fruit (Purple nightshade)
Solidago
    californica, see Solidago velutina ssp. californica
    confinis (Southern goldenrod)
    velutina ssp. californica (California goldenrod)
Sonchus
    asper ssp. asper (Prickly sow-thistle)*
    oleraceus (Sow-thistle)*
Spartina foliosa (Cord grass)
Spartium junceum (Spanish broom)*
Spergula arvensis (Corn spurrey)*
Spergularia
    bocconi (Boccone's sand spurrey)*
    macrotheca ssp. macrotheca (Sticky sand spurrey)
    marina (Salt marsh sand spurrey)
    villosa (Hairy sand spurrey)*
Sphaeralcea
    ambigua var. ambigua (Apricot mallow)
    ambigua var. rosacea (Rosy apricot mallow)
    ambigua var. rugosa (Desert globemallow)
    coulteri (Coulter's globemallow)
    rusbyi var. eremicola (Rusby's desert mallow)
Sphenosciadium capitellatum (Ranger's buttons)
Sporobolus airoides (Alkali sacaton)
Stachys
    ajugoides var. rigida (Rigid hedge nettle)
    albens (White hedge nettle)
    bullata (California hedge nettle)
Stanleya
    elata (Panamint prince's plume)
    pinnata var. inyoensis (Inyo prince's plume)
    pinnata var. pinnata (Prince's plume)
Stebbinsoseris heterocarpa (Brown microseris)
Stellaria
    calycantha (Northern starwort)
    longipes ssp. longipes (Meadow starwort)
    media (Chickweed)*
Stephanomeria
    cichoriacea (Chicory-leaved stephanomeria)
    diegensis (San Diego wreathplant)
    exigua ssp. coronaria (Whiteplume wirelettuce)
    exigua ssp. deanei (Deane's wirelettuce)
    exigua ssp. exigua (Small wirelettuce)
    pauciflora var. pauciflora (Desert straw)
    spinosa, see Pleiacanthus spinosus
    virgata ssp. pleurocarpa (Wand wirelettuce)
    virgata ssp. virgata (Twiggy wreathplant)
Stillingia
    linearifolia (Narrow-leaved stillingia)
    spinulosa (Broad-leaved stillingia)
Stipa
    arida (Mormon needlegrass)
    coronata (Giant stipa)
    diegoensis (San Diego County needlegrass)
    hymenoides (Indian ricegrass)
    occidentalis var. occidentalis (Western needlegrass)
    parishii (Parish's needlegrass)
    speciosa (Desert needlegrass)
Streptanthella longirostris (Longbeak streptanthella)
Streptanthus
    bernardinus (Laguna Mountains jewelflower)
    campestris (Southern jewelflower)
    cordatus (Heartleaf jewelflower)
Stylocline
    gnaphaloides (Everlasting neststraw)
    micropoides (Woollyhead neststraw)
Stylomecon heterophylla (Wind poppy)
Styrax
    officinalis var. redivivus, see Styrax redivivus
     redivivus (Snowdrop bush)
Suaeda
    esteroa (Estuary sea-blite)
    moquinii (Rush seepweed)
    taxifolia (Woolly sea-blite)
Swallenia alexandrae (Eureka Valley dune grass)
Swertia
    neglecta (Pine green-gentian)
    parryi (Parry's green-gentian)
Symphoricarpos
    albus var. laevigatus (White snowberry)
    longiflorus (Desert snowberry)
    mollis (Creeping snowberry)
    mollis fruit (Creeping snowberry)
    rotundifolius var. parishii (Mountain snowberry)
Symphyotrichum
    ascendens (Long-leaved aster)
    chilense (Chile aster)
    defoliatum (San Bernardino aster)
    greatae (Greata's aster)
    lanceolatus ssp. hesperium (Western lanceleaf aster)
    spathulatum var. spathulatum (Western mountain aster)
    subulatum var. parviflorum (Slim aster)
Syntrichopappus fremontii (Fremont's syntrichopappus)
Tamarix
    aphylla (Athel)*
    parviflora (Small-flowered tamarisk)*
    ramosissima (Salt cedar)*
Tanacetum parthenium (Feverfew)*
Taraxacum
    californicum (California dandelion)
    officinale (Dandelion)*
Tauschia
    arguta (Southern tauschia)
    parishii (Parish's tauschia)
Tetracoccus
    dioicus (Parry's tetracoccus)
    hallii (Hall's purple bush)
Tetradymia
    axillaris var. longispina (Longspine horsebrush)
    canescens (Spineless horsebrush)
    comosa (Cottonthorn)
    spinosa (Spiny horsebrush)
    stenolepis (Mojave cottonthorn)
Tetragonia tetragonioides (New Zealand spinach)*
Tetraneuris acaulis var. arizonica (Arizona hymenoxys)
Tetrapteron palmeri (Palmer's sun cup)
Thalictrum
    fendleri var. fendleri (Fendler's meadow-rue)
    fendleri var. polycarpum (pistillate flowers) (Meadow-rue)
    fendleri var. polycarpum (staminate flowers) (Meadow-rue)
    sparsiflorum (Few-flowered meadow-rue)
Thamnosma montana (Turpentine-broom)
Thelypodium
    integrifolium ssp. affine (Entire-leaved thelypodium)
    stenopetalum (Slender-petalled mustard)
Thermopsis
    macrophylla var. argentata (Silvery false-lupine)
    macrophylla var. semota (Velvety false-lupine)
Thymophylla pentachaeta var. belenidium (Five-needled thymophylla)
Thysanocarpus
    curvipes (Fringe-pod)
    laciniatus (Lace-pod)
Tidestromia oblongifolia (Honeysweet)
Tiquilia
    canescens (Woody crinklemat)
    nuttallii (Nuttall's crinklemat)
    palmeri (Palmer's crinklemat)
    plicata (Fanleaf crinklemat)
Torilis
    arvensis (Field hedge-parsley)*
    nodosa (Hedge-parsley)*
Toxicodendron diversilobum (Western poison oak)
Toxicoscordion
    brevibracteatum (Desert zygadene)
    fremontii (Star lily)
    venenosum var. venenosum (Death camas)
Tragia ramosa (Noseburn)
Tragopogon
    dubius (Yellow salsify)*
     porrifolius (Purple salsify)*
Trianthema portulacastrum (Lowland purslane)
Tribulus terrestris (Puncture vine)*
Tricardia watsonii (Three-hearts)
Trichoptilium incisum (Yellowheads)
Trichostema
    austromontanum ssp. austromontanum (Southern bluecurls)
    austromontanum ssp. compactum (Hidden Lake bluecurls)
    lanatum (Woolly bluecurls)
    lanceolatum (Vinegar weed)
    micranthum (Smallflower bluecurls)
    parishii (Parish's bluecurls)
Tridens muticus (Slim tridens)
Trifolium
    albopurpureum var. albopurpureum (Indian clover)
    barbigerum (Bearded clover)
    ciliolatum (Tree clover)
    depauperatum var. truncatum (Balloon clover)
    gracilentum var. gracilentum (Pin-point clover)
    hirtum (Rose clover)*
    longipes var. longipes (Summer clover)
    microcephalum (Small-head field clover)
    monanthum var. grantianum (Grant's carpet clover)
    monanthum var. monanthum (Mountain carpet clover)
    obtusiflorum (Creek clover)
    pratense (Red clover)*
    repens (White clover)*
    variegatum (Whitetip clover)
    willdenovii (Tomcat clover)
    wormskioldii (Mountain clover)
Triodanis biflora (Venus looking-glass)
Triteleia
    laxa (Ithuriel's spear)
    lugens (Coast range triteleia)
Triticum aestivum (Common wheat)*
Trixis californica var. californica (California trixis)
Tropidocarpum gracile (Dobiepod)
Turricula parryi, see Eriodictyon parryi
Turritis glabra (Tower mustard)
Typha
    domingensis (Southern cattail)
    latifolia (Broad-leaved cattail)
Umbellularia californica (California bay)
Uropappus lindleyi (Silver puffs)
Urtica
    dioica ssp. holosericea (Hoary nettle)
    urens (Dwarf nettle)*
Vaccinium ovatum (California huckleberry)
Vachellia farnesiana var. farnesiana (Sweet acacia)*
Venegasia carpesioides (Canyon sunflower)
Veratrum californicum var. californicum (Corn lily)
Verbascum
    thapsus (Woolly mullein)*
    virgatum (Wand mullein)*
Verbena
    bracteata (Big-bract verbena)
    gooddingii (Goodding's verbena)
    lasiostachys var. lasiostachys (Western vervain)
    lasiostachys var. scabrida (Robust vervain)
    menthifolia (Mint-leaved vervain)
Veronica
    americana (American speedwell)
    anagallis-aquatica (Water speedwell)*
    peregrina ssp. xalapensis (Purslane speedwell)
    persica (Persian speedwell)*
    serpyllifolia ssp. humifusa (Thyme-leaved speedwell)*
Vicia
    americana var. americana (American vetch)
    hassei (Slender vetch)
    sativa (Spring vetch)*
    villosa (Winter vetch)*
Viguiera
    laciniata, see Bahiopsis laciniata
    parishii, see Bahiopsis parishii
Vinca major (Periwinkle)*
Viola
    adunca ssp. adunca (Blue violet)
    douglasii (Douglas's violet)
    lobata ssp. lobata (Yellow violet)
    macloskeyi (Macloskey's violet)
    pedunculata (Johnny-jump-up)
    pinetorum ssp. grisea (Gray-leaved violet)
    pinetorum ssp. pinetorum (Pine violet)
    purpurea ssp. quercetorum (Oak violet)
    sheltonii (Shelton's violet)
Vitis
    girdiana (Wild grape)
    girdiana fruit (Wild grape)
Vulpia
    microstachys (Small fescue)
    myuros var. hirsuta (Hairy rattail fescue)*
    octoflora var. hirtella (Six-weeks fescue)
    octoflora var. octoflora (Slender fescue)
Washingtonia filifera (California fan palm)
Woodsia oregana (Oregon cliff fern)
Woodwardia fimbriata (Giant chain fern)
Wyethia ovata (Mule's ears)
Xanthisma gracile (Slender goldenweed)
Xanthium
    spinosum (Spiny cocklebur)
    strumarium (Cocklebur)
Xylococcus
    bicolor (Mission manzanita)
    bicolor fruit (Mission manzanita)
Xylorhiza
    cognata (Mecca-aster)
    orcuttii (Orcutt's woody-aster)
     tortifolia var. tortifolia (Mojave-aster)
Yucca
    baccata (Banana yucca)
    brevifolia (Joshua tree)
    schidigera (Mojave yucca)
    whipplei, see Hesperoyucca whipplei
Zeltnera venustum (Canchalagua)
Zigadenus
    brevibracteatus, see Toxicoscordion brevibracteatum
    fremontii, see Toxicoscordion fremontii
    venenosus var. venenosus, see Toxicoscordion venenosum var. venenosum
Ziziphus parryi (Lotebush)