Abies concolor (White fir)
Abronia
    maritima (Red sand verbena)
    nana ssp. covillei (Coville's dwarf abronia)
    turbinata (White sand verbena)
    umbellata ssp. umbellata (Pink sand verbena)
    villosa var. aurita (Desert sand verbena)
    villosa var. villosa (Desert sand verbena)
Abutilon palmeri (Indian-mallow)
Acacia
    baileyana (Cootamundra wattle)*
    farnesiana var. farnesiana (Sweet acacia)*
    greggii (Catclaw acacia)
    longifolia (Golden wattle)*
Acalypha californica (California copperleaf)
Acamptopappus
    shockleyi (Shockley's goldenheads)
    sphaerocephalus (Goldenheads)
Acanthomintha
    ilicifolia (San Diego thornmint)
    obovata ssp. cordata (Heartleaf thornmint)
Acer
    glabrum (Mountain maple)
    macrophyllum (Big leaf maple)
    negundo var. californicum (Box elder)
Achillea millefolium (Yarrow)
Achnatherum
    coronatum (Giant stipa)
    diegoense (San Diego County needlegrass)
    hymenoides (Indian ricegrass)
    occidentale ssp. occidentale (Western needlegrass)
    parishii (Parish's needlegrass)
    speciosum (Desert needlegrass)
Achyrachaena mollis (Blow wives)
Achyronychia cooperi (Frostmat)
Acourtia microcephala (Perezia)
Acroptilon repens (Russian knapweed)*
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 (Shaw's agave)
    utahensis (Utah agave)
Ageratina adenophora (Thoroughwort)*
Agoseris
    grandiflora (Mountain dandelion)
    retrorsa (Spearleaf mountain dandelion)
Agropyron desertorum (Desert crested wheatgrass)*
Agrostis
    idahoensis (Idaho bentgrass)
    pallens (Seashore bentgrass)
    viridis (Green bentgrass)*
Albizia lophantha (Plume acacia)*
Aliciella
    hutchinsifolia (Desert pale gilia)
    latifolia (Broadleaf gilia)
    triodon (Sand gilia)
Alisma plantago-aquatica (Water plantain)
Allionia incarnata (Windmills)
Allium
    amplectens (Narrow-leaved onion)
    atrorubens var. atrorubens (Wild onion)
    burlewii (Burlew's onion)
    campanulatum (Sierra onion)
    fimbriatum var. fimbriatum (Fringed onion)
    haematochiton (Red-skinned onion)
    howellii var. clokeyi (Mt. Pinos onion)
    lacunosum var. davisiae (Davis's pitted onion)
    monticola (San Bernardino mountain onion)
    parryi (Parry's fringed onion)
    peninsulare var. peninsulare (Peninsular onion)
    praecox (Early onion)
Allophyllum
    divaricatum (Purple false-gilia)
    gilioides ssp. gilioides (Dense false-gilia)
    gilioides ssp. violaceum (Violet false-gilia)
    glutinosum (Sticky false-gilia)
    integrifolium (White false-gilia)
Alnus rhombifolia (White alder)
Alopecurus aequalis (Shortawn foxtail)
Aloysia wrightii (Vera dulce)
Amaranthus
    albus (Pigweed amaranth)*
    blitoides (Prostrate amaranth)
    californicus (California amaranth)
    fimbriatus (Fringed amaranth)
    torreyi (Torrey's amaranth)
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)
Amelanchier utahensis (Utah serviceberry)
Ammannia coccinea (Red ammannia)
Amorpha
    californica var. californica (California false-indigo)
    fruticosa (Western false-indigo)
Amphipappus fremontii ssp. fremontii (Chaffbush)
Amsinckia
    menziesii var. intermedia (Common fiddleneck)
    menziesii var. menziesii (Small-flowered fiddleneck)
    spectabilis var. spectabilis (Seaside fiddleneck)
    tessellata var. tessellata (Checker fiddleneck)
Amsonia tomentosa (Woolly amsonia)
Anagallis arvensis (Scarlet pimpernel)*
Anemopsis californica (Yerba mansa)
Angelica
    lineariloba (Soda straw)
    tomentosa (Woolly angelica)
Anisocoma acaulis (Scalebud)
Antennaria
    dimorpha (Low pussytoes)
    rosea ssp. confinis (Rosy pussytoes)
Anthemis
    arvensis (Corn chamomile)*
    cotula (Mayweed)*
Anthriscus caucalis (Bur-chervil)*
Antirrhinum
    coulterianum (White snapdragon)
    filipes (Desert twining snapdragon)
    kelloggii (Twining snapdragon)
    multiflorum (Rose snapdragon)
    nuttallianum ssp. nuttallianum (Violet snapdragon)
Anulocaulis annulatus (Sticky ringstem)
Aphanes occidentalis (Western lady's mantle)
Apiastrum angustifolium (Wild celery)
Apium graveolens (Celery)*
Apocynum
    androsaemifolium (Spreading dogbane)
    cannabinum (Indian hemp)
Aptenia cordifolia (Baby sun rose)*
Aquilegia formosa (Columbine)
Arabidopsis thaliana (Mouse-ear cress)*
Arabis
    glabra var. glabra (Tower mustard)
    holboellii var. pinetorum (Pine rock-cress)
    parishii (Parish's rock-cress)
    perennans (Perennial rock-cress)
    platysperma var. platysperma (Broad-seeded rock-cress)
    pulchra var. gracilis (Slender beautiful rock-cress)
    pulchra var. pulchra (Beautiful rock-cress)
    rectissima var. rectissima (Bristly-leaved rock-cress)
    repanda var. repanda (Yosemite rock-cress)
    shockleyi (Shockley's rock-cress)
    sparsiflora var. arcuata (Arched elegant rock-cress)
    sparsiflora var. californica (Elegant rock-cress)
Aralia californica (California aralia)
Arbutus
    menziesii (Pacific madrone)
    menziesii fruit (Pacific madrone)
Arceuthobium
    abietinum (Fir dwarf mistletoe)
    campylopodum (Pine dwarf mistletoe)
Arctostaphylos
    catalinae (Santa Catalina Island manzanita)
    confertiflora (Santa Rosa Island manzanita)
    gabrielensis (San Gabriel manzanita)
    glandulosa ssp. crassifolia (Del Mar manzanita)
    glandulosa ssp. adamsii (Adams' manzanita)
    glandulosa ssp. glaucomollis (Eastwood manzanita)
    glandulosa ssp. mollis (Santa Monica Mountains manzanita)
    glandulosa ssp. mollis, fruit (Santa Monica Mountains manzanita)
    glandulosa ssp. zacaensis (Zaca Lake manzanita)
    glauca (Bigberry manzanita)
    insularis (Island manzanita)
    otayensis (Otay manzanita)
    parryana ssp. deserticum (Parry's manzanita)
    parryana ssp. parryana (Parry's manzanita)
    patula (Greenleaf manzanita)
    peninsularis (Peninsular manzanita)
    pringlei ssp. drupacea (Pink-bracted manzanita)
    pungens (Mexican manzanita)
    tomentosa (Woollyleaf manzanita)
Arenaria
    kingii (King's sandwort)
    lanuginosa ssp. saxosa (Spreading sandwort)
    macradenia var. macradenia (Desert sandwort)
    ursina (Bear Valley sandwort)
Argemone
    corymbosa (Mojave prickly poppy)
    munita (Chicalote)
Argyrochosma jonesii (Jones' cloak fern)
Aristida
    adscensionis (Three-awn)
    purpurea var. nealleyi (Nealley three-awn)
Armeria maritima ssp. californica (California sea-pink)
Arnica
    chamissonis ssp. foliosa (Meadow arnica)
    mollis (Soft arnica)
Artemisia
    californica (California sagebrush)
    douglasiana (Mugwort)
    dracunculus (Wild tarragon)
    ludoviciana ssp. incompta (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 (Alpine aster)
    ascendens (Long-leaved aster)
    bernardinus (San Bernardino aster)
    chilensis (Chile aster)
    greatae (Greata's aster)
    laneolatus ssp. hesperius (Western lanceleaf aster)
    occidentalis var. occidentalis (Western mountain aster)
    subulatus var. ligulatus (Slim aster)
Astragalus
    albens (Cushenbury milkvetch)
    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. 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)
    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 ssp. canescens (Fourwing saltbush)
    confertifolia (Shadscale saltbush)
    elegans var. fasciculata (Wheelscale saltbush)
    glauca (Waxy saltbush)*
    hymenelytra (Desert-holly)
    lentiformis ssp. lentiformis (Quail bush)
    lentiformis ssp. torreyi (Torrey's saltbush)
    leucophylla (Beach saltbush)
    pacifica (Pacific saltbush)
    phyllostegia (Arrowscale)
    polycarpa (Cattle spinach)
    semibaccata (Australian saltbush)*
    triangularis (Arrowleaf saltbush)
    watsonii (Watson's saltbush)
Avena
    barbata (Slender oats)*
    fatua (Common wild oats)*
Ayenia compacta (Ayenia)
Baccharis
    brachyphylla (Shortleaf baccharis)
    douglasii (Salt marsh baccharis)
    emoryi (Emory baccharis)
    malibuensis (Malibu baccharis)
    pilularis (Coyote brush)
    plummerae ssp. plummerae (Plummer's baccharis)
    salicifolia (Mulefat)
    sarothroides (Broom baccharis)
    sergiloides (Desert baccharis)
    vanessae (Encinitas baccharis)
Bahia dissecta (Ragged-leaf bahia)
Bahiopsis
    laciniata (San Diego County goldeneye)
    parishii (Parish's goldeneye)
    reticulata (Mojave goldeneye)
Baileya
    multiradiata var. multiradiata (Desert marigold)
    pauciradiata (Lax flower)
    pleniradiata (Woolly marigold)
Balsamorhiza deltoidea (Deltoid balsamroot)
Barbarea orthoceras (Winter cress)
Bassia hyssopifolia (Five-hook bassia)
Batis maritima (Saltwort)
Bebbia juncea var. aspera (Sweetbush)
Bellis perennis (English daisy)*
Berberis
    aquifolium var. repens (Creeping grape holly)
    fremontii (Fremont's barberry)
    nevinii (Nevin's barberry)
    pinnata ssp. pinnata (California barberry)
Bergerocactus emoryi (Golden-spined cereus)
Bernardia myricifolia (Bernardia)
Berula erecta (Water parsnip)
Beta vulgaris (Common beet)*
Bidens
    laevis (Smooth beggar-ticks)
    pilosa var. pilosa (Common beggar-ticks)*
Bituminaria bituminosa (Pitch trefoil)*
Blennosperma nanum var. nanum (Yellow carpet)
Bloomeria crocea (Golden stars)
Boerhavia
    coccinea (Red boerhavia)
    intermedia (Fivewing boerhavia)
    triquetra (Slender boerhavia)
    wrightii (Wright's boerhavia)
Bolboschoenus maritimus (Marsh bulrush)
Boschniakia strobilacea (California groundcone)
Bouteloua
    aristidoides (Needle grama)
    eriopoda (Black grama)
    gracilis (Blue grama)
    trifida (Red grama)
Bowlesia incana (Bowlesia)
Boykinia
    occidentalis (Coast boykinia)
    rotundifolia (Round-leaved boykinia)
Brachypodium distachyon (Purple false-brome)*
Brandegea bigelovii (Brandegea)
Brassica
    fruticulosa (Mediterranean cabbage)*
    nigra (Black mustard)*
    rapa (Field mustard)*
    tournefortii (Saharan mustard)*
Brickellia
    arguta (Spearleaf brickellbush)
    californica (California brickellbush)
    desertorum (Desert brickellbush)
    frutescens (Shrubby brickellbush)
    incana (Woolly brickellbush)
    microphylla (Little-leaved brickellbush)
    multiflora (Gum-leaved brickellbush)
    nevinii (Nevin's brickellbush)
    oblongifolia var. linifolia (Narrow-leaved brickellbush)
Brodiaea
    elegans (Harvest brodiaea)
    filifolia (Thread-leaved brodiaea)
    orcuttii (Orcutt's brodiaea)
    santarosae (Santa Rosa basalt brodiaea)
    terrestris ssp. kernensis (Earth brodiaea)
Bromus
    carinatus var. carinatus (California brome)
    carinatus var. maritimus (Seaside brome)
    diandrus (Ripgut brome)*
    hordeaceus (Soft chess)*
    madritensis ssp. rubens (Red brome)*
    tectorum (Cheat grass)*
    trinii (Chilean chess)*
Buddleja utahensis (Panamint butterfly bush)
Bursera microphylla (Elephant tree)