Listed Flowering Plants
893 Records
Parameters:
- Species Groups: Flowering Plants
- Listing Statuses: Endangered, Threatened, Emergency Listing, Endangered, Emergency Listing, Threatened, Similarity of Appearance (Endangered), Similarity of Appearance (Threatened)
- Listed in the US
When searching by State,
please note that a species will show up in the report only if it has a spatial current range.
State associations for a species are based on a spatial current range delineated by
FWS biologists in TESS (and not all species have spatial current range delineated at
the present time).
The current range of species entities consisting of one or more populations does not include states or countries outside those population boundaries, even though the species may occur there in a population not covered by the Endangered Species Act.
The current range of species entities consisting of one or more populations does not include states or countries outside those population boundaries, even though the species may occur there in a population not covered by the Endangered Species Act.
| Scientific Name | Common Name | Lead Region | Federal Listing Status | Where Listed |
|---|---|---|---|---|
| Abronia macrocarpa | Large-fruited sand-verbena | 2 | Endangered | Wherever found |
| Abutilon eremitopetalum | No common name | 1 | Endangered | Wherever found |
| Abutilon menziesii | Ko`oloa`ula | 1 | Endangered | Wherever found |
| Abutilon sandwicense | No common name | 1 | Endangered | Wherever found |
| Acaena exigua | Liliwai | 1 | Endangered | Wherever found |
| Acanthomintha ilicifolia | San Diego thornmint | 8 | Threatened | Wherever found |
| Acanthomintha obovata ssp. duttonii | San Mateo thornmint | 8 | Endangered | Wherever found |
| Achyranthes mutica | No common name | 1 | Endangered | Wherever found |
| Achyranthes splendens var. rotundata | Round-leaved chaff-flower | 1 | Endangered | Wherever found |
| Aconitum noveboracense | Northern wild monkshood | 3 | Threatened | Wherever found |
| Aeschynomene virginica | Sensitive joint-vetch | 5 | Threatened | Wherever found |
| Agalinis acuta | Sandplain gerardia | 5 | Endangered | Wherever found |
| Agave eggersiana | No common name | 4 | Endangered | Wherever found |
| Alectryon macrococcus | Mahoe | 1 | Endangered | Wherever found |
| Allium munzii | Munz's onion | 8 | Endangered | Wherever found |
| Alopecurus aequalis var. sonomensis | Sonoma alopecurus | 8 | Endangered | Wherever found |
| Amaranthus brownii | No common name | 1 | Endangered | Wherever found |
| Amaranthus pumilus | Seabeach amaranth | 4 | Threatened | Wherever found |
| Ambrosia cheiranthifolia | South Texas ambrosia | 2 | Endangered | Wherever found |
| Ambrosia pumila | San Diego ambrosia | 8 | Endangered | Wherever found |
| Amorpha crenulata | Crenulate lead-plant | 4 | Endangered | Entire |
| Amphianthus pusillus | Little amphianthus | 4 | Threatened | Wherever found |
| Amsinckia grandiflora | Large-flowered fiddleneck | 8 | Endangered | Wherever found |
| Amsonia kearneyana | Kearney's blue-star | 2 | Endangered | Wherever found |
| Apios priceana | Price''s potato-bean | 4 | Threatened | Entire |
| Arabis georgiana | Georgia rockcress | 4 | Threatened | Wherever found |
| Arabis hoffmannii | Hoffmann's rock-cress | 8 | Endangered | Wherever found |
| Arabis macdonaldiana | McDonald's rock-cress | 8 | Endangered | Wherever found |
| Arabis perstellata | Braun's rock-cress | 4 | Endangered | Wherever found |
| Arctomecon humilis | Dwarf Bear-poppy | 6 | Endangered | Wherever found |
| Arctostaphylos confertiflora | Santa Rosa Island manzanita | 8 | Endangered | Wherever found |
| Arctostaphylos franciscana | Franciscan manzanita | 8 | Endangered | Wherever found |
| Arctostaphylos glandulosa ssp. crassifolia | Del Mar manzanita | 8 | Endangered | Wherever found |
| Arctostaphylos hookeri var. ravenii | Presidio Manzanita | 8 | Endangered | Wherever found |
| Arctostaphylos morroensis | Morro manzanita | 8 | Threatened | Wherever found |
| Arctostaphylos myrtifolia | Ione manzanita | 8 | Threatened | Wherever found |
| Arctostaphylos pallida | Pallid manzanita | 8 | Threatened | Wherever found |
| Arenaria paludicola | Marsh Sandwort | 8 | Endangered | Wherever found |
| Arenaria ursina | Bear Valley sandwort | 8 | Threatened | Wherever found |
| Argemone pleiacantha ssp. pinnatisecta | Sacramento prickly poppy | 2 | Endangered | Wherever found |
| Argyroxiphium kauense | Mauna Loa (=Ka'u) silversword | 1 | Endangered | Wherever found |
| Argyroxiphium sandwicense ssp. macrocephalum | `Ahinahina | 1 | Threatened | Wherever found |
| Argyroxiphium sandwicense ssp. sandwicense | `Ahinahina | 1 | Endangered | Wherever found |
| Argythamnia blodgettii | Blodgett's silverbush | 4 | Threatened | Entire |
| Aristida chaseae | No common name | 4 | Endangered | Wherever found |
| Aristida portoricensis | Pelos del diablo | 4 | Endangered | Wherever found |
| Asclepias meadii | Mead's milkweed | 3 | Threatened | Wherever found |
| Asclepias prostrata | Prostrate milkweed | 2 | Endangered | Entire |
| Asclepias welshii | Welsh's milkweed | 6 | Threatened | Wherever found |
| Asimina tetramera | Four-petal pawpaw | 4 | Endangered | Entire |
| Astelia waialealae | Pa`iniu | 1 | Endangered | Wherever found |
| Astragalus albens | Cushenbury milk-vetch | 8 | Endangered | Wherever found |
| Astragalus ampullarioides | Shivwits milk-vetch | 6 | Endangered | Wherever found |
| Astragalus applegatei | Applegate's milk-vetch | 8 | Endangered | Wherever found |
| Astragalus bibullatus | Guthrie's (=Pyne's) ground-plum | 4 | Endangered | Wherever found |
| Astragalus brauntonii | Braunton's milk-vetch | 8 | Endangered | Wherever found |
| Astragalus clarianus | Clara Hunt's milk-vetch | 8 | Endangered | Wherever found |
| Astragalus cremnophylax var. cremnophylax | Sentry milk-vetch | 2 | Endangered | Wherever found |
| Astragalus holmgreniorum | Holmgren milk-vetch | 6 | Endangered | Wherever found |
| Astragalus humillimus | Mancos milk-vetch | 2 | Endangered | Wherever found |
| Astragalus jaegerianus | Lane Mountain milk-vetch | 8 | Endangered | Wherever found |
| Astragalus lentiginosus var. coachellae | Coachella Valley milk-vetch | 8 | Endangered | Wherever found |
| Astragalus lentiginosus var. piscinensis | Fish Slough milk-vetch | 8 | Threatened | Wherever found |
| Astragalus magdalenae var. peirsonii | Peirson's milk-vetch | 8 | Threatened | Wherever found |
| Astragalus montii | Heliotrope milk-vetch | 6 | Threatened | Wherever found |
| Astragalus osterhoutii | Osterhout milkvetch | 6 | Endangered | Wherever found |
| Astragalus phoenix | Ash meadows milk-vetch | 8 | Threatened | Wherever found |
| Astragalus pycnostachyus var. lanosissimus | Ventura Marsh Milk-vetch | 8 | Endangered | Wherever found |
| Astragalus robbinsii var. jesupii | Jesup's milk-vetch | 5 | Endangered | Wherever found |
| Astragalus tener var. titi | Coastal dunes milk-vetch | 8 | Endangered | Wherever found |
| Astragalus tricarinatus | Triple-ribbed milk-vetch | 8 | Endangered | Wherever found |
| Astrophytum asterias | Star cactus | 2 | Endangered | Wherever found |
| Atriplex coronata var. notatior | San Jacinto Valley crownscale | 8 | Endangered | Wherever found |
| Auerodendron pauciflorum | No common name | 4 | Endangered | Wherever found |
| Ayenia limitaris | Texas ayenia | 2 | Endangered | Wherever found |
| Baccharis vanessae | Encinitas baccharis | 8 | Threatened | Wherever found |
| Banara vanderbiltii | Palo de ramon | 4 | Endangered | Wherever found |
| Baptisia arachnifera | Hairy rattleweed | 4 | Endangered | Wherever found |
| Berberis nevinii | Nevin's barberry | 8 | Endangered | Wherever found |
| Berberis pinnata ssp. insularis | Island Barberry | 8 | Endangered | Wherever found |
| Betula uber | Virginia round-leaf birch | 5 | Threatened | Wherever found |
| Bidens amplectens | Ko`oko`olau | 1 | Endangered | Wherever found |
| Bidens campylotheca ssp. pentamera | Ko`oko`olau | 1 | Endangered | Wherever found |
| Bidens campylotheca ssp. waihoiensis | Ko`oko`olau | 1 | Endangered | Wherever found |
| Bidens conjuncta | Ko`oko`olau | 1 | Endangered | Wherever found |
| Bidens hillebrandiana ssp. hillebrandiana | kookoolau | 1 | Endangered | Wherever found |
| Bidens micrantha ssp. ctenophylla | Ko`oko`olau | 1 | Endangered | Wherever found |
| Bidens micrantha ssp. kalealaha | Ko`oko`olau | 1 | Endangered | Wherever found |
| Bidens wiebkei | Ko`oko`olau | 1 | Endangered | Wherever found |
| Blennosperma bakeri | Sonoma sunshine | 8 | Endangered | Wherever found |
| Boechera serotina | Shale barren rock cress | 5 | Endangered | Wherever found |
| Boltonia decurrens | Decurrent false aster | 3 | Threatened | Wherever found |
| Bonamia grandiflora | Florida bonamia | 4 | Threatened | Entire |
| Bonamia menziesii | No common name | 1 | Endangered | Wherever found |
| Brickellia mosieri | Florida brickell-bush | 4 | Endangered | Entire |
| Brighamia insignis | Olulu | 1 | Endangered | Wherever found |
| Brighamia rockii | Pua `ala | 1 | Endangered | Wherever found |
| Brodiaea filifolia | Thread-leaved brodiaea | 8 | Threatened | Wherever found |
| Brodiaea pallida | Chinese Camp brodiaea | 8 | Threatened | Wherever found |
| Bulbophyllum guamense | Cebello halumtano | 1 | Threatened | Wherever found |
| Buxus vahlii | Vahl's boxwood | 4 | Endangered | Wherever found |
| Calamagrostis expansa | Maui reedgrass | 1 | Endangered | Wherever found |
| Calamagrostis hillebrandii | Hillebrand's reedgrass | 1 | Endangered | Wherever found |
| Callicarpa ampla | Capa rosa | 4 | Endangered | Wherever found |
| Callirhoe scabriuscula | Texas poppy-mallow | 2 | Endangered | Wherever found |
| Calochortus tiburonensis | Tiburon mariposa lily | 8 | Threatened | Wherever found |
| Calyptranthes thomasiana | No common name | 4 | Endangered | Wherever found |
| Calyptridium pulchellum | Mariposa pussypaws | 8 | Threatened | Wherever found |
| Calyptronoma rivalis | Palma de manaca | 4 | Threatened | Wherever found |
| Calystegia stebbinsii | Stebbins' morning-glory | 8 | Endangered | Wherever found |
| Campanula robinsiae | Brooksville bellflower | 4 | Endangered | Entire |
| Canavalia molokaiensis | `Awikiwiki | 1 | Endangered | Wherever found |
| Canavalia napaliensis | `Awikiwiki | 1 | Endangered | Wherever found |
| Canavalia pubescens | `Awikiwiki | 1 | Endangered | Wherever found |
| Cardamine micranthera | Small-anthered bittercress | 4 | Endangered | Wherever found |
| Carex albida | White sedge | 8 | Endangered | Wherever found |
| Carex lutea | Golden sedge | 4 | Endangered | Wherever found |
| Carex specuicola | Navajo sedge | 2 | Threatened | Wherever found |
| Castilleja affinis ssp. neglecta | Tiburon paintbrush | 8 | Endangered | Wherever found |
| Castilleja campestris ssp. succulenta | Fleshy owl's-clover | 8 | Threatened | Wherever found |
| Castilleja cinerea | Ash-grey paintbrush | 8 | Threatened | Wherever found |
| Castilleja mollis | Soft-leaved paintbrush | 8 | Endangered | Wherever found |
| Catesbaea melanocarpa | No common name | 4 | Endangered | Wherever found |
| Caulanthus californicus | California jewelflower | 8 | Endangered | Wherever found |
| Ceanothus ferrisae | Coyote ceanothus | 8 | Endangered | Wherever found |
| Ceanothus ophiochilus | Vail Lake ceanothus | 8 | Threatened | Wherever found |
| Ceanothus roderickii | Pine Hill ceanothus | 8 | Endangered | Wherever found |
| Cenchrus agrimonioides | Kamanomano | 1 | Endangered | Wherever found |
| Centaurium namophilum | Spring-loving centaury | 8 | Threatened | Wherever found |
| Cercocarpus traskiae | Catalina Island mountain-mahogany | 8 | Endangered | Wherever found |
| Cereus eriophorus var. fragrans | Fragrant prickly-apple | 4 | Endangered | Entire |
| Chamaecrista glandulosa var. mirabilis | No common name | 4 | Endangered | Wherever found |
| Chamaecrista lineata keyensis | Big Pine partridge pea | 4 | Endangered | Entire |
| Chamaesyce deltoidea pinetorum | Pineland sandmat | 4 | Threatened | Entire |
| Chamaesyce deltoidea serpyllum | Wedge spurge | 4 | Endangered | Entire |
| Chamaesyce deltoidea ssp. deltoidea | Deltoid spurge | 4 | Endangered | Entire |
| Chamaesyce garberi | Garber's spurge | 4 | Threatened | Entire |
| Chamaesyce hooveri | Hoover's spurge | 8 | Threatened | Wherever found |
| Charpentiera densiflora | Papala | 1 | Endangered | Wherever found |
| Chionanthus pygmaeus | Pygmy fringe-tree | 4 | Endangered | Entire |
| Chlorogalum purpureum | Purple amole | 8 | Threatened | Wherever found |
| Chorizanthe howellii | Howell's spineflower | 8 | Endangered | Wherever found |
| Chorizanthe orcuttiana | Orcutt's spineflower | 8 | Endangered | Wherever found |
| Chorizanthe pungens var. hartwegiana | Ben Lomond spineflower | 8 | Endangered | Wherever found |
| Chorizanthe pungens var. pungens | Monterey spineflower | 8 | Threatened | Wherever found |
| Chorizanthe robusta var. hartwegii | Scotts Valley spineflower | 8 | Endangered | Wherever found |
| Chorizanthe robusta var. robusta | Robust spineflower | 8 | Endangered | Wherever found |
| Chorizanthe valida | Sonoma spineflower | 8 | Endangered | Wherever found |
| Chromolaena frustrata | Cape Sable Thoroughwort | 4 | Endangered | Entire |
| Cirsium fontinale var. fontinale | Fountain thistle | 8 | Endangered | Wherever found |
| Cirsium fontinale var. obispoense | Chorro Creek bog thistle | 8 | Endangered | Wherever found |
| Cirsium hydrophilum var. hydrophilum | Suisun thistle | 8 | Endangered | Wherever found |
| Cirsium loncholepis | La Graciosa thistle | 8 | Endangered | Wherever found |
| Cirsium pitcheri | Pitcher's thistle | 3 | Threatened | Wherever found |
| Cirsium vinaceum | Sacramento Mountains thistle | 2 | Threatened | Wherever found |
| Cirsium wrightii | Wright's marsh thistle | 2 | Threatened | Entire |
| Clarkia franciscana | Presidio clarkia | 8 | Endangered | Wherever found |
| Clarkia imbricata | Vine Hill clarkia | 8 | Endangered | Wherever found |
| Clarkia speciosa ssp. immaculata | Pismo clarkia | 8 | Endangered | Wherever found |
| Clarkia springvillensis | Springville clarkia | 8 | Threatened | Wherever found |
| Clematis morefieldii | Morefield''s leather flower | 4 | Endangered | Entire |
| Clematis socialis | Alabama leather flower | 4 | Endangered | Wherever found |
| Clermontia drepanomorpha | `Oha wai | 1 | Endangered | Wherever found |
| Clermontia lindseyana | `Oha wai | 1 | Endangered | Wherever found |
| Clermontia oblongifolia ssp. brevipes | `Oha wai | 1 | Endangered | Wherever found |
| Clermontia oblongifolia ssp. mauiensis | `Oha wai | 1 | Endangered | Wherever found |
| Clermontia peleana | `Oha wai | 1 | Endangered | Wherever found |
| Clermontia pyrularia | `Oha wai | 1 | Endangered | Wherever found |
| Clermontia samuelii | `Oha wai | 1 | Endangered | Wherever found |
| Clitoria fragrans | Pigeon wings | 4 | Threatened | Entire |
| Colubrina oppositifolia | Kauila | 1 | Endangered | Wherever found |
| Conradina brevifolia | Short-leaved rosemary | 4 | Endangered | Entire |
| Conradina etonia | Etonia rosemary | 4 | Endangered | Entire |
| Conradina glabra | Apalachicola rosemary | 4 | Endangered | Entire |
| Conradina verticillata | Cumberland rosemary | 4 | Threatened | Wherever found |
| Consolea corallicola | Florida semaphore Cactus | 4 | Endangered | Entire |
| Cordia bellonis | No common name | 4 | Endangered | Wherever found |
| Cordylanthus maritimus ssp. maritimus | Salt marsh bird's-beak | 8 | Endangered | Wherever found |
| Cordylanthus mollis ssp. mollis | Soft bird's-beak | 8 | Endangered | Wherever found |
| Cordylanthus palmatus | Palmate-bracted bird's beak | 8 | Endangered | Wherever found |
| Cordylanthus tenuis ssp. capillaris | Pennell's bird's-beak | 8 | Endangered | Wherever found |
| Cornutia obovata | Palo de nigua | 4 | Endangered | Wherever found |
| Coryphantha ramillosa | Bunched cory cactus | 2 | Threatened | Wherever found |
| Coryphantha robbinsorum | Cochise pincushion cactus | 2 | Threatened | Wherever found |
| Coryphantha scheeri var. robustispina | Pima pineapple cactus | 2 | Endangered | Wherever found |
| Coryphantha sneedii var. leei | Lee pincushion cactus | 2 | Threatened | Wherever found |
| Coryphantha sneedii var. sneedii | Sneed pincushion cactus | 2 | Endangered | Wherever found |
| Cranichis ricartii | No common name | 4 | Endangered | Wherever found |
| Crescentia portoricensis | Higuero de sierra | 4 | Endangered | Wherever found |
| Crotalaria avonensis | Avon Park harebells | 4 | Endangered | Entire |
| Cryptantha crassipes | Terlingua Creek cat's-eye | 2 | Endangered | Wherever found |
| Cucurbita okeechobeensis ssp. okeechobeensis | Okeechobee gourd | 4 | Endangered | Entire |
| Cyanea acuminata | Haha | 1 | Endangered | Wherever found |
| Cyanea asarifolia | Haha | 1 | Endangered | Wherever found |
| Cyanea asplenifolia | Haha | 1 | Endangered | Wherever found |
| Cyanea calycina | Haha | 1 | Endangered | Wherever found |
| Cyanea copelandii ssp. copelandii | Haha | 1 | Endangered | Wherever found |
| Cyanea copelandii ssp. haleakalaensis | Haha | 1 | Endangered | Wherever found |
| Cyanea crispa | haha | 1 | Endangered | Wherever found |
| Cyanea dolichopoda | Haha | 1 | Endangered | Wherever found |
| Cyanea dunbariae | haha | 1 | Endangered | Wherever found |
| Cyanea duvalliorum | haha | 1 | Endangered | Wherever found |
| Cyanea eleeleensis | Haha | 1 | Endangered | Wherever found |
| Cyanea gibsonii | haha | 1 | Endangered | Wherever found |
| Cyanea glabra | Haha | 1 | Endangered | Wherever found |
| Cyanea grimesiana ssp. grimesiana | Haha | 1 | Endangered | Wherever found |
| Cyanea grimesiana ssp. obatae | Haha | 1 | Endangered | Wherever found |
| Cyanea hamatiflora ssp. carlsonii | Haha | 1 | Endangered | Wherever found |
| Cyanea hamatiflora ssp. hamatiflora | Haha | 1 | Endangered | Wherever found |
| Cyanea horrida | haha nui | 1 | Endangered | Wherever found |
| Cyanea humboldtiana | Haha | 1 | Endangered | Wherever found |
| Cyanea kauaulaensis | No common name | 1 | Endangered | Wherever found |
| Cyanea kolekoleensis | Haha | 1 | Endangered | Wherever found |
| Cyanea koolauensis | Haha | 1 | Endangered | Wherever found |
| Cyanea kuhihewa | Haha | 1 | Endangered | Wherever found |
| Cyanea kunthiana | Haha | 1 | Endangered | Wherever found |
| Cyanea lanceolata | Haha | 1 | Endangered | Wherever found |
| Cyanea lobata | Haha | 1 | Endangered | Wherever found |
| Cyanea longiflora | Haha | 1 | Endangered | Wherever found |
| Cyanea magnicalyx | haha | 1 | Endangered | Wherever found |
| Cyanea mannii | Haha | 1 | Endangered | Wherever found |
| Cyanea maritae | haha | 1 | Endangered | Wherever found |
| Cyanea marksii | Haha | 1 | Endangered | Wherever found |
| Cyanea mauiensis | haha | 1 | Endangered | Wherever found |
| Cyanea mceldowneyi | Haha | 1 | Endangered | Wherever found |
| Cyanea munroi | haha | 1 | Endangered | Wherever found |
| Cyanea obtusa | Haha | 1 | Endangered | Wherever found |
| Cyanea pinnatifida | Haha | 1 | Endangered | Wherever found |
| Cyanea platyphylla | `aku`aku | 1 | Endangered | Wherever found |
| Cyanea procera | Haha | 1 | Endangered | Wherever found |
| Cyanea profuga | Haha | 1 | Endangered | Wherever found |
| Cyanea purpurellifolia | Haha | 1 | Endangered | Wherever found |
| Cyanea recta | Haha | 1 | Threatened | Wherever found |
| Cyanea remyi | Haha | 1 | Endangered | Wherever found |
| Cyanea rivularis | Haha | 1 | Endangered | Wherever found |
| Cyanea shipmanii | Haha | 1 | Endangered | Wherever found |
| Cyanea solanacea | Popolo | 1 | Endangered | Wherever found |
| Cyanea stictophylla | Haha | 1 | Endangered | Wherever found |
| Cyanea st.-johnii | Haha | 1 | Endangered | Wherever found |
| Cyanea superba | Haha | 1 | Endangered | Wherever found |
| Cyanea tritomantha | `aku | 1 | Endangered | Wherever found |
| Cyanea truncata | Haha | 1 | Endangered | Wherever found |
| Cyanea undulata | Haha | 1 | Endangered | Wherever found |
| Cycladenia humilis var. jonesii | Jones Cycladenia | 6 | Threatened | Wherever found |
| Cyperus fauriei | No common name | 1 | Endangered | Wherever found |
| Cyperus neokunthianus | No common name | 1 | Endangered | Wherever found |
| Cyperus pennatiformis | No common name | 1 | Endangered | Wherever found |
| Cyperus trachysanthos | Pu`uka`a | 1 | Endangered | Wherever found |
| Cyrtandra crenata | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra cyaneoides | Mapele | 1 | Endangered | Wherever found |
| Cyrtandra dentata | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra ferripilosa | haiwale | 1 | Endangered | Wherever found |
| Cyrtandra filipes | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra giffardii | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra gracilis | Haiwale | 1 | Endangered | Wherever found |
| Cyrtandra hematos | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra kaulantha | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra limahuliensis | Ha`iwale | 1 | Threatened | Wherever found |
| Cyrtandra munroi | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra nanawaleensis | haiwale | 1 | Endangered | Wherever found |
| Cyrtandra oenobarba | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra oxybapha | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra paliku | Haiwale | 1 | Endangered | Wherever found |
| Cyrtandra polyantha | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra sessilis | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra subumbellata | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra tintinnabula | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra viridiflora | Ha`iwale | 1 | Endangered | Wherever found |
| Cyrtandra wagneri | haiwale | 1 | Endangered | Wherever found |
| Cyrtandra waiolani | Haiwale | 1 | Endangered | Wherever found |
| Dalea carthagenensis floridana | Florida prairie-clover | 4 | Endangered | Entire |
| Dalea foliosa | Leafy prairie-clover | 3 | Endangered | Entire |
| Daphnopsis helleriana | No common name | 4 | Endangered | Wherever found |
| Deeringothamnus pulchellus | Beautiful pawpaw | 4 | Endangered | Entire |
| Deeringothamnus rugelii | Rugel's pawpaw | 4 | Endangered | Entire |
| Deinandra (=Hemizonia) conjugens | Otay tarplant | 8 | Threatened | Wherever found |
| Deinandra increscens ssp. villosa | Gaviota Tarplant | 8 | Endangered | Wherever found |
| Delissea rhytidosperma | No common name | 1 | Endangered | Wherever found |
| Delissea subcordata | Oha | 1 | Endangered | Wherever found |
| Delissea undulata | No common name | 1 | Endangered | Wherever found |
| Delphinium bakeri | Baker's larkspur | 8 | Endangered | Wherever found |
| Delphinium luteum | Yellow larkspur | 8 | Endangered | Wherever found |
| Dendrobium guamense | No common name | 1 | Threatened | Wherever found |
| Dicerandra christmanii | Garrett's mint | 4 | Endangered | Entire |
| Dicerandra cornutissima | Longspurred mint | 4 | Endangered | Entire |
| Dicerandra frutescens | Scrub mint | 4 | Endangered | Entire |
| Dicerandra immaculata | Lakela's mint | 4 | Endangered | Entire |
| Digitaria pauciflora | Florida pineland crabgrass | 4 | Threatened | Entire |
| Diplacus vandenbergensis | Vandenberg monkeyflower | 8 | Endangered | Wherever found |
| Dodecahema leptoceras | Slender-horned spineflower | 8 | Endangered | Wherever found |
| Dracaena fernaldii | Hala pepe | 1 | Endangered | Wherever found |
| Dracaena forbesii | Hala pepe | 1 | Endangered | Wherever found |
| Dracaena konaensis | Hala pepe | 1 | Endangered | Wherever found |
| Dubautia herbstobatae | Na`ena`e | 1 | Endangered | Wherever found |
| Dubautia imbricata ssp. imbricata | Na`ena`e | 1 | Endangered | Wherever found |
| Dubautia kalalauensis | Naenae | 1 | Endangered | Wherever found |
| Dubautia kenwoodii | Naenae | 1 | Endangered | Wherever found |
| Dubautia latifolia | Koholapehu | 1 | Endangered | Wherever found |
| Dubautia pauciflorula | Na`ena`e | 1 | Endangered | Wherever found |
| Dubautia plantaginea ssp. humilis | Na`ena`e | 1 | Endangered | Wherever found |
| Dubautia plantaginea ssp. magnifolia | Na`ena`e | 1 | Endangered | Wherever found |
| Dubautia waialealae | Na`ena`e | 1 | Endangered | Wherever found |
| Dudleya abramsii ssp. parva | Conejo dudleya | 8 | Threatened | Wherever found |
| Dudleya cymosa ssp. marcescens | Marcescent dudleya | 8 | Threatened | Wherever found |
| Dudleya cymosa ssp. ovatifolia | Santa Monica Mountains dudleyea | 8 | Threatened | Wherever found |
| Dudleya setchellii | Santa Clara Valley dudleya | 8 | Endangered | Wherever found |
| Dudleya stolonifera | Laguna Beach liveforever | 8 | Threatened | Wherever found |
| Dudleya traskiae | Santa Barbara Island liveforever | 8 | Endangered | Wherever found |
| Dudleya verityi | Verity's dudleya | 8 | Threatened | Wherever found |
| Echinacea laevigata | Smooth coneflower | 4 | Threatened | Wherever found |
| Echinocactus horizonthalonius var. nicholii | Nichol's Turk's head cactus | 2 | Endangered | Wherever found |
| Echinocereus arizonicus ssp. arizonicus | Arizona hedgehog cactus | 2 | Endangered | Wherever found |
| Echinocereus chisoensis var. chisoensis | Chisos Mountain hedgehog Cactus | 2 | Threatened | Wherever found |
| Echinocereus fendleri var. kuenzleri | Kuenzler hedgehog cactus | 2 | Threatened | Wherever found |
| Echinocereus reichenbachii var. albertii | Black lace cactus | 2 | Endangered | Wherever found |
| Echinocereus viridiflorus var. davisii | Davis' green pitaya | 2 | Endangered | Wherever found |
| Echinomastus erectocentrus var. acunensis | Acuña Cactus | 2 | Endangered | Wherever found |
| Enceliopsis nudicaulis var. corrugata | Ash Meadows sunray | 8 | Threatened | Wherever found |
| Eragrostis fosbergii | Fosberg's love grass | 1 | Endangered | Wherever found |
| Eremalche kernensis | Kern mallow | 8 | Endangered | Wherever found |
| Eriastrum densifolium ssp. sanctorum | Santa Ana River woolly-star | 8 | Endangered | Wherever found |
| Erigeron decumbens | Willamette daisy | 1 | Endangered | Wherever found |
| Erigeron parishii | Parish's daisy | 8 | Threatened | Wherever found |
| Erigeron rhizomatus | Zuni fleabane | 2 | Threatened | Wherever found |
| Eriodictyon altissimum | Indian Knob mountainbalm | 8 | Endangered | Wherever found |
| Eriodictyon capitatum | Lompoc yerba santa | 8 | Endangered | Wherever found |
| Eriogonum apricum (incl. var. prostratum) | Ione (incl. Irish Hill) buckwheat | 8 | Endangered | Wherever found |
| Eriogonum codium | Umtanum desert buckwheat | 1 | Threatened | Wherever found |
| Eriogonum gypsophilum | Gypsum wild-buckwheat | 2 | Threatened | Wherever found |
| Eriogonum kennedyi var. austromontanum | Southern mountain wild-buckwheat | 8 | Threatened | Wherever found |
| Eriogonum longifolium var. gnaphalifolium | Scrub buckwheat | 4 | Threatened | Entire |
| Eriogonum ovalifolium var. vineum | Cushenbury buckwheat | 8 | Endangered | Wherever found |
| Eriogonum ovalifolium var. williamsiae | Steamboat buckwheat | 8 | Endangered | Wherever found |
| Eriogonum pelinophilum | Clay-Loving wild buckwheat | 6 | Endangered | Wherever found |
| Eriogonum tiehmii | Tiehm's buckwheat | 8 | Endangered | Entire |
| Eriophyllum latilobum | San Mateo woolly sunflower | 8 | Endangered | Wherever found |
| Eryngium aristulatum var. parishii | San Diego button-celery | 8 | Endangered | Wherever found |
| Eryngium constancei | Loch Lomond coyote thistle | 8 | Endangered | Wherever found |
| Eryngium cuneifolium | Snakeroot | 4 | Endangered | Entire |
| Eryngium sparganophyllum | Arizona eryngo | 2 | Endangered | Entire |
| Erysimum capitatum var. angustatum | Contra Costa wallflower | 8 | Endangered | Wherever found |
| Erysimum menziesii | Menzies' wallflower | 8 | Endangered | Wherever found |
| Erysimum teretifolium | Ben Lomond wallflower | 8 | Endangered | Wherever found |
| Erythronium propullans | Minnesota dwarf trout lily | 3 | Endangered | Wherever found |
| Escobaria minima | Nellie''s cory cactus | 2 | Endangered | Wherever found |
| Eugenia bryanii | No common name | 1 | Endangered | Wherever found |
| Eugenia haematocarpa | Uvillo | 4 | Endangered | Wherever found |
| Eugenia koolauensis | Nioi | 1 | Endangered | Wherever found |
| Eugenia woodburyana | No common name | 4 | Threatened | Wherever found |
| Euphorbia celastroides var. kaenana | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia deppeana | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia eleanoriae | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia haeleeleana | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia halemanui | 'Akoko | 1 | Endangered | Wherever found |
| Euphorbia herbstii | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia kuwaleana | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia remyi var. kauaiensis | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia remyi var. remyi | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia rockii | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia skottsbergii var. skottsbergii | `Akoko | 1 | Endangered | Wherever found |
| Euphorbia telephioides | Telephus spurge | 4 | Threatened | Entire |
| Eutrema penlandii | Penland alpine fen mustard | 6 | Threatened | Entire |
| Exocarpos luteolus | Heau | 1 | Endangered | Wherever found |
| Exocarpos menziesii | Heau | 1 | Endangered | Entire |
| Festuca hawaiiensis | No common name | 1 | Endangered | Wherever found |
| Festuca ligulata | Guadalupe fescue | 2 | Endangered | Wherever found |
| Festuca molokaiensis | No common name | 1 | Endangered | Wherever found |
| Flueggea neowawraea | Mehamehame | 1 | Endangered | Wherever found |
| Fremontodendron californicum ssp. decumbens | Pine Hill flannelbush | 8 | Endangered | Wherever found |
| Fremontodendron mexicanum | Mexican flannelbush | 8 | Endangered | Wherever found |
| Fritillaria gentneri | Gentner's Fritillary | 1 | Endangered | Wherever found |
| Galactia smallii | Small's milkpea | 4 | Endangered | Entire |
| Galium californicum ssp. sierrae | El Dorado bedstraw | 8 | Endangered | Wherever found |
| Gardenia brighamii | Hawaiian gardenia | 1 | Endangered | Wherever found |
| Gardenia mannii | Nanu | 1 | Endangered | Wherever found |
| Gardenia remyi | Nanu | 1 | Endangered | Wherever found |
| Geocarpon minimum | No common name | 4 | Threatened | Wherever found |
| Geranium arboreum | Nohoanu | 1 | Endangered | Wherever found |
| Geranium hanaense | Nohoanu | 1 | Endangered | Wherever found |
| Geranium hillebrandii | Nohoanu | 1 | Endangered | Wherever found |
| Geranium kauaiense | Nohoanu | 1 | Endangered | Wherever found |
| Geranium multiflorum | Nohoanu | 1 | Endangered | Wherever found |
| Gesneria pauciflora | No common name | 4 | Threatened | Wherever found |
| Geum radiatum | Spreading avens | 4 | Endangered | Wherever found |
| Gilia tenuiflora ssp. arenaria | Monterey gilia | 8 | Endangered | Wherever found |
| Gilia tenuiflora ssp. hoffmannii | Hoffmann's slender-flowered gilia | 8 | Endangered | Wherever found |
| Goetzea elegans | Beautiful goetzea | 4 | Endangered | Wherever found |
| Gonocalyx concolor | No common name | 4 | Endangered | Wherever found |
| Gouania hillebrandii | No common name | 1 | Endangered | Wherever found |
| Gouania meyenii | No common name | 1 | Endangered | Wherever found |
| Gouania vitifolia | No common name | 1 | Endangered | Wherever found |
| Graptopetalum bartramii | Bartram's stonecrop | 2 | Threatened | Wherever found |
| Grindelia fraxinipratensis | Ash Meadows gumplant | 8 | Threatened | Wherever found |
| Hackelia venusta | Showy stickseed | 1 | Endangered | Wherever found |
| Haplostachys haplostachya | Honohono | 1 | Endangered | Wherever found |
| Harperocallis flava | Harper's beauty | 4 | Endangered | Entire |
| Harrisia (=Cereus) aboriginum (=gracilis) | Aboriginal Prickly-apple | 4 | Endangered | Entire |
| Harrisia portoricensis | Higo Chumbo | 4 | Threatened | Wherever found |
| Hedeoma todsenii | Todsen's pennyroyal | 2 | Endangered | Wherever found |
| Hedyotis megalantha | Paudedo | 1 | Endangered | Wherever found |
| Hedyotis purpurea var. montana | Roan Mountain bluet | 4 | Endangered | Wherever found |
| Helenium virginicum | Virginia sneezeweed | 5 | Threatened | Wherever found |
| Helianthemum greenei | Island rush-rose | 8 | Threatened | Wherever found |
| Helianthus paradoxus | Pecos (=puzzle, =paradox) sunflower | 2 | Threatened | Wherever found |
| Helianthus schweinitzii | Schweinitz's sunflower | 4 | Endangered | Wherever found |
| Helianthus verticillatus | Whorled Sunflower | 4 | Endangered | Entire |
| Helonias bullata | Swamp pink | 5 | Threatened | Entire |
| Heritiera longipetiolata | Ufa-halomtano | 1 | Endangered | Wherever found |
| Hesperolinon congestum | Marin dwarf-flax | 8 | Threatened | Wherever found |
| Hesperomannia arborescens | No common name | 1 | Endangered | Wherever found |
| Hesperomannia arbuscula | No common name | 1 | Endangered | Wherever found |
| Hesperomannia lydgatei | No common name | 1 | Endangered | Wherever found |
| Hexastylis naniflora | Dwarf-flowered heartleaf | 4 | Threatened | Wherever found |
| Hibiscadelphus distans | Kauai hau kuahiwi | 1 | Endangered | Wherever found |
| Hibiscadelphus giffardianus | Hau kuahiwi | 1 | Endangered | Wherever found |
| Hibiscadelphus hualalaiensis | Hau kuahiwi | 1 | Endangered | Wherever found |
| Hibiscadelphus woodii | Hau kuahiwi | 1 | Endangered | Wherever found |
| Hibiscus arnottianus ssp. immaculatus | Koki`o ke`oke`o | 1 | Endangered | Wherever found |
| Hibiscus brackenridgei | (=Native yellow hibiscus) ma`o hau hele | 1 | Endangered | Wherever found |
| Hibiscus clayi | Clay's hibiscus | 1 | Endangered | Wherever found |
| Hibiscus dasycalyx | Neches River rose-mallow | 2 | Threatened | Wherever found |
| Hibiscus waimeae ssp. hannerae | Koki`o ke`oke`o | 1 | Endangered | Wherever found |
| Hoffmannseggia tenella | Slender rush-pea | 2 | Endangered | Wherever found |
| Holocarpha macradenia | Santa Cruz tarplant | 8 | Threatened | Wherever found |
| Hudsonia montana | Mountain golden heather | 4 | Threatened | Wherever found |
| Hymenoxys herbacea | Lakeside daisy | 3 | Threatened | Wherever found |
| Hymenoxys texana | Texas prairie dawn-flower | 2 | Endangered | Wherever found |
| Hypericum cumulicola | Highlands scrub hypericum | 4 | Endangered | Entire |
| Ilex cookii | Cook's holly | 4 | Endangered | Wherever found |
| Ilex sintenisii | No common name | 4 | Endangered | Wherever found |
| Iliamna corei | Peter's Mountain mallow | 5 | Endangered | Wherever found |
| Ipomopsis polyantha | Pagosa skyrocket | 6 | Endangered | Wherever found |
| Ipomopsis sancti-spiritus | Holy Ghost ipomopsis | 2 | Endangered | Wherever found |
| Iris lacustris | Dwarf lake iris | 3 | Threatened | Wherever found |
| Ischaemum byrone | Hilo ischaemum | 1 | Endangered | Wherever found |
| Isodendrion hosakae | Aupaka | 1 | Endangered | Wherever found |
| Isodendrion laurifolium | Aupaka | 1 | Endangered | Wherever found |
| Isodendrion longifolium | Aupaka | 1 | Threatened | Wherever found |
| Isodendrion pyrifolium | wahine noho Kula | 1 | Endangered | Wherever found |
| Isotria medeoloides | Small whorled pogonia | 5 | Threatened | Entire |
| Ivesia kingii var. eremica | Ash Meadows ivesia | 8 | Threatened | Wherever found |
| Ivesia webberi | Webber's ivesia | 8 | Threatened | Wherever found |
| Jacquemontia reclinata | Beach jacquemontia | 4 | Endangered | Entire |
| Joinvillea ascendens ascendens | `Ohe | 1 | Endangered | Wherever found |
| Juglans jamaicensis | West Indian Walnut (=Nogal) | 4 | Endangered | Wherever found |
| Justicia cooleyi | Cooley's water-willow | 4 | Endangered | Entire |
| Kadua cookiana | 'Awiwi | 1 | Endangered | Wherever found |
| Kadua cordata remyi | kopa | 1 | Endangered | Wherever found |
| Kadua coriacea | Kio`ele | 1 | Endangered | Wherever found |
| Kadua degeneri | No common name | 1 | Endangered | Wherever found |
| Kadua fluviatilis | Kamapua`a | 1 | Endangered | Wherever found |
| Kadua haupuensis | No common name | 1 | Endangered | Wherever found |
| Kadua laxiflora | pilo | 1 | Endangered | Wherever found |
| Kadua parvula | No common name | 1 | Endangered | Wherever found |
| Kadua st.-johnii | No common name | 1 | Endangered | Wherever found |
| Kanaloa kahoolawensis | Kohe malama malama o Kanaloa | 1 | Endangered | Wherever found |
| Keysseria (=Lagenifera) erici | No common name | 1 | Endangered | Wherever found |
| Keysseria (=Lagenifera) helenae | No common name | 1 | Endangered | Wherever found |
| Kokia cookei | Koki`o | 1 | Endangered | Wherever found |
| Kokia drynarioides | Koki`o | 1 | Endangered | Wherever found |
| Kokia kauaiensis | Koki`o | 1 | Endangered | Wherever found |
| Korthalsella degeneri | Hulumoa | 1 | Endangered | Wherever found |
| Labordia cyrtandrae | Kamakahala | 1 | Endangered | Wherever found |
| Labordia helleri | Kamakahala | 1 | Endangered | Wherever found |
| Labordia lorenciana | No common name | 1 | Endangered | Wherever found |
| Labordia lydgatei | Kamakahala | 1 | Endangered | Wherever found |
| Labordia pumila | Kamakahala | 1 | Endangered | Wherever found |
| Labordia tinifolia var. lanaiensis | Kamakahala | 1 | Endangered | Wherever found |
| Labordia tinifolia var. wahiawaensis | Kamakahala | 1 | Endangered | Wherever found |
| Labordia triflora | Kamakahala | 1 | Endangered | Wherever found |
| Lasthenia burkei | Burke's goldfields | 8 | Endangered | Wherever found |
| Lasthenia conjugens | Contra Costa goldfields | 8 | Endangered | Wherever found |
| Layia carnosa | Beach layia | 8 | Threatened | Wherever found |
| Leavenworthia crassa | Fleshy-fruit gladecress | 4 | Endangered | Wherever found |
| Leavenworthia exigua laciniata | Kentucky glade cress | 4 | Threatened | Wherever found |
| Leavenworthia texana | Texas golden Gladecress | 2 | Endangered | Wherever found |
| Lepidium arbuscula | `Anaunau | 1 | Endangered | Wherever found |
| Lepidium barnebyanum | Barneby ridge-cress | 6 | Endangered | Wherever found |
| Lepidium orbiculare | No common name | 1 | Endangered | Wherever found |
| Lepidium papilliferum | Slickspot peppergrass | 1 | Threatened | Entire |
| Leptocereus grantianus | No common name | 4 | Endangered | Wherever found |
| Lespedeza leptostachya | Prairie bush-clover | 3 | Threatened | Wherever found |
| Lesquerella congesta | Dudley Bluffs bladderpod | 6 | Threatened | Wherever found |
| Lesquerella kingii ssp. bernardina | San Bernardino Mountains bladderpod | 8 | Endangered | Wherever found |
| Lesquerella lyrata | Lyrate bladderpod | 4 | Threatened | Wherever found |
| Lesquerella perforata | Spring Creek bladderpod | 4 | Endangered | Wherever found |
| Lesquerella tumulosa | Kodachrome bladderpod | 6 | Endangered | Wherever found |
| Lessingia germanorum (=L.g. var. germanorum) | San Francisco lessingia | 8 | Endangered | Wherever found |
| Liatris helleri | Heller's blazingstar | 4 | Threatened | Wherever found |
| Liatris ohlingerae | Scrub blazingstar | 4 | Endangered | Entire |
| Lilaeopsis schaffneriana var. recurva | Huachuca water-umbel | 2 | Endangered | Wherever found |
| Lilium occidentale | Western lily | 8 | Endangered | Wherever found |
| Lilium pardalinum ssp. pitkinense | Pitkin Marsh lily | 8 | Endangered | Wherever found |
| Limnanthes floccosa ssp. californica | Butte County meadowfoam | 8 | Endangered | Wherever found |
| Limnanthes pumila ssp. grandiflora | Large-flowered woolly meadowfoam | 1 | Endangered | Wherever found |
| Limnanthes vinculans | Sebastopol meadowfoam | 8 | Endangered | Wherever found |
| Lindera melissifolia | Pondberry | 4 | Endangered | Wherever found |
| Linum arenicola | Sand flax | 4 | Endangered | Entire |
| Linum carteri carteri | Carter's small-flowered flax | 4 | Endangered | Entire |
| Lipochaeta fauriei | nehe | 1 | Endangered | Wherever found |
| Lipochaeta lobata var. leptophylla | nehe | 1 | Endangered | Wherever found |
| Lipochaeta micrantha | nehe | 1 | Endangered | Wherever found |
| Lipochaeta venosa | nehe | 1 | Endangered | Wherever found |
| Lipochaeta waimeaensis | nehe | 1 | Endangered | Wherever found |
| Lithophragma maximum | San Clemente Island woodland-star | 8 | Endangered | Wherever found |
| Lobelia koolauensis | No common name | 1 | Endangered | Wherever found |
| Lobelia monostachya | No common name | 1 | Endangered | Wherever found |
| Lobelia niihauensis | No common name | 1 | Endangered | Wherever found |
| Lobelia oahuensis | No common name | 1 | Endangered | Wherever found |
| Lomatium cookii | Cook's lomatium | 1 | Endangered | Wherever found |
| Lupinus aridorum | Scrub lupine | 4 | Endangered | Entire |
| Lupinus constancei | Lassics lupine | 8 | Endangered | Entire |
| Lupinus nipomensis | Nipomo Mesa lupine | 8 | Endangered | Wherever found |
| Lupinus sulphureus ssp. kincaidii | Kincaid's Lupine | 1 | Threatened | Wherever found |
| Lupinus tidestromii | Clover (Tidestrom''s) lupine | 8 | Endangered | Wherever found |
| Lyonia truncata var. proctorii | No common name | 4 | Endangered | Wherever found |
| Lysimachia asperulaefolia | Rough-leaved loosestrife | 4 | Endangered | Wherever found |
| Lysimachia daphnoides | lehua makanoe | 1 | Endangered | Wherever found |
| Lysimachia filifolia | No common name | 1 | Endangered | Wherever found |
| Lysimachia iniki | No common name | 1 | Endangered | Wherever found |
| Lysimachia lydgatei | No common name | 1 | Endangered | Wherever found |
| Lysimachia maxima | No common name | 1 | Endangered | Wherever found |
| Lysimachia pendens | No common name | 1 | Endangered | Wherever found |
| Lysimachia scopulensis | No common name | 1 | Endangered | Wherever found |
| Lysimachia venosa | No common name | 1 | Endangered | Wherever found |
| Macbridea alba | White birds-in-a-nest | 4 | Threatened | Entire |
| Maesa walkeri | No common name | 1 | Threatened | Wherever found |
| Malacothamnus fasciculatus var. nesioticus | Santa Cruz Island bush-mallow | 8 | Endangered | Wherever found |
| Malacothrix indecora | Santa Cruz Island malacothrix | 8 | Endangered | Wherever found |
| Malacothrix squalida | Island malacothrix | 8 | Endangered | Wherever found |
| Manihot walkerae | Walker's manioc | 2 | Endangered | Wherever found |
| Marshallia mohrii | Mohr's Barbara's buttons | 4 | Threatened | Wherever found |
| Melanthera kamolensis | nehe | 1 | Endangered | Wherever found |
| Melanthera tenuifolia | nehe | 1 | Endangered | Wherever found |
| Melicope adscendens | Alani | 1 | Endangered | Wherever found |
| Melicope balloui | Alani | 1 | Endangered | Wherever found |
| Melicope christophersenii | Alani | 1 | Endangered | Wherever found |
| Melicope cornuta var. cornuta | No common name | 1 | Endangered | Wherever found |
| Melicope cornuta var. decurrens | No common name | 1 | Endangered | Wherever found |
| Melicope degeneri | Alani | 1 | Endangered | Wherever found |
| Melicope haupuensis | Alani | 1 | Endangered | Wherever found |
| Melicope hiiakae | Alani | 1 | Endangered | Wherever found |
| Melicope knudsenii | Alani | 1 | Endangered | Wherever found |
| Melicope lydgatei | Alani | 1 | Endangered | Wherever found |
| Melicope makahae | Alani | 1 | Endangered | Wherever found |
| Melicope mucronulata | Alani | 1 | Endangered | Wherever found |
| Melicope munroi | Alani | 1 | Endangered | Wherever found |
| Melicope ovalis | Alani | 1 | Endangered | Wherever found |
| Melicope pallida | Alani | 1 | Endangered | Wherever found |
| Melicope paniculata | Alani | 1 | Endangered | Wherever found |
| Melicope puberula | Alani | 1 | Endangered | Wherever found |
| Melicope quadrangularis | Alani | 1 | Endangered | Wherever found |
| Melicope reflexa | Alani | 1 | Endangered | Wherever found |
| Melicope remyi | No common name | 1 | Endangered | Wherever found |
| Melicope rostrata | Pilo kea lau li`i | 1 | Endangered | Wherever found |
| Melicope saint-johnii | Alani | 1 | Endangered | Wherever found |
| Melicope zahlbruckneri | Alani | 1 | Endangered | Wherever found |
| Mentzelia leucophylla | Ash Meadows blazingstar | 8 | Threatened | Wherever found |
| Mezoneuron kavaiense | Uhiuhi | 1 | Endangered | Wherever found |
| Mimulus michiganensis | Michigan monkey-flower | 3 | Endangered | Wherever found |
| Mirabilis macfarlanei | MacFarlane's four-o'clock | 1 | Threatened | Wherever found |
| Mitracarpus maxwelliae | No common name | 4 | Endangered | Wherever found |
| Mitracarpus polycladus | No common name | 4 | Threatened | Wherever found |
| Monardella viminea | Willowy monardella | 8 | Endangered | Wherever found |
| Monolopia (=Lembertia) congdonii | San Joaquin wooly-threads | 8 | Endangered | Wherever found |
| Mucuna persericea | sea bean | 1 | Endangered | Wherever found |
| Myrcia paganii | No common name | 4 | Endangered | Wherever found |
| Myrsine fosbergii | Kolea | 1 | Endangered | Wherever found |
| Myrsine juddii | Kolea | 1 | Endangered | Wherever found |
| Myrsine knudsenii | Kolea | 1 | Endangered | Wherever found |
| Myrsine linearifolia | Kolea | 1 | Threatened | Wherever found |
| Myrsine mezii | Kolea | 1 | Endangered | Wherever found |
| Myrsine vaccinioides | Kolea | 1 | Endangered | Wherever found |
| Navarretia fossalis | Spreading navarretia | 8 | Threatened | Wherever found |
| Navarretia leucocephala ssp. pauciflora (=N. pauciflora) | Few-flowered navarretia | 8 | Endangered | Wherever found |
| Navarretia leucocephala ssp. plieantha | Many-flowered navarretia | 8 | Endangered | Wherever found |
| Neostapfia colusana | Colusa grass | 8 | Threatened | Wherever found |
| Neraudia angulata | No common name | 1 | Endangered | Wherever found |
| Neraudia ovata | No common name | 1 | Endangered | Wherever found |
| Neraudia sericea | No common name | 1 | Endangered | Wherever found |
| Nervilia jacksoniae | No common name | 1 | Threatened | Wherever found |
| Nesogenes rotensis | No common name | 1 | Endangered | Wherever found |
| Nitrophila mohavensis | Amargosa niterwort | 8 | Endangered | Wherever found |
| Nolina brittoniana | Britton's beargrass | 4 | Endangered | Entire |
| Nothocestrum breviflorum | `Aiea | 1 | Endangered | Wherever found |
| Nothocestrum latifolium | `Aiea | 1 | Endangered | Wherever found |
| Nothocestrum peltatum | `Aiea | 1 | Endangered | Wherever found |
| Nototrichium humile | Kulu`i | 1 | Endangered | Wherever found |
| Ochrosia haleakalae | Holei | 1 | Endangered | Wherever found |
| Ochrosia kilaueaensis | Holei | 1 | Endangered | Wherever found |
| Oenothera deltoides ssp. howellii | Antioch Dunes evening-primrose | 8 | Endangered | Wherever found |
| Opuntia treleasei | Bakersfield cactus | 8 | Endangered | Wherever found |
| Orcuttia californica | California Orcutt grass | 8 | Endangered | Wherever found |
| Orcuttia inaequalis | San Joaquin Valley Orcutt grass | 8 | Threatened | Wherever found |
| Orcuttia pilosa | Hairy Orcutt grass | 8 | Endangered | Wherever found |
| Orcuttia tenuis | Slender Orcutt grass | 8 | Threatened | Wherever found |
| Orcuttia viscida | Sacramento Orcutt grass | 8 | Endangered | Wherever found |
| Osmoxylon mariannense | No common name | 1 | Endangered | Wherever found |
| Ottoschulzia rhodoxylon | Palo de rosa | 4 | Threatened | Wherever found |
| Oxypolis canbyi | Canby's dropwort | 4 | Endangered | Wherever found |
| Oxytheca parishii var. goodmaniana | Cushenbury oxytheca | 8 | Endangered | Wherever found |
| Oxytropis campestris var. chartacea | Fassett's locoweed | 3 | Threatened | Wherever found |
| Packera franciscana | San Francisco Peaks ragwort | 2 | Threatened | Wherever found |
| Panicum fauriei var. carteri | Carter's panicgrass | 1 | Endangered | Wherever found |
| Panicum niihauense | Lau `ehu | 1 | Endangered | Wherever found |
| Paronychia chartacea | Papery whitlow-wort | 4 | Threatened | Entire |
| Parvisedum leiocarpum | Lake County stonecrop | 8 | Endangered | Wherever found |
| Pectis imberbis | beardless chinchweed | 2 | Endangered | Wherever found |
| Pedicularis furbishiae | Furbish lousewort | 5 | Threatened | Entire |
| Pediocactus bradyi | Brady pincushion cactus | 2 | Endangered | Wherever found |
| Pediocactus despainii | San Rafael cactus | 6 | Endangered | Wherever found |
| Pediocactus (=Echinocactus,=Utahia) sileri | Siler pincushion cactus | 2 | Threatened | Wherever found |
| Pediocactus knowltonii | Knowlton's cactus | 2 | Endangered | Wherever found |
| Pediocactus peeblesianus ssp. fickeiseniae | Fickeisen plains cactus | 2 | Endangered | Wherever found |
| Pediocactus peeblesianus ssp. peeblesianus | Peebles Navajo cactus | 2 | Endangered | Wherever found |
| Pediocactus winkleri | Winkler cactus | 6 | Threatened | Wherever found |
| Penstemon debilis | Parachute beardtongue | 6 | Threatened | Wherever found |
| Penstemon haydenii | Blowout penstemon | 6 | Endangered | Wherever found |
| Penstemon penlandii | Penland beardtongue | 6 | Endangered | Wherever found |
| Pentachaeta bellidiflora | White-rayed pentachaeta | 8 | Endangered | Wherever found |
| Pentachaeta lyonii | Lyon's pentachaeta | 8 | Endangered | Wherever found |
| Peperomia subpetiolata | `Ala `ala wai nui | 1 | Endangered | Wherever found |
| Peperomia wheeleri | Wheeler's peperomia | 4 | Endangered | Wherever found |
| Peucedanum sandwicense | Makou | 1 | Threatened | Wherever found |
| Phacelia argentea | Sand dune phacelia | 1 | Threatened | Entire |
| Phacelia argillacea | Clay phacelia | 6 | Endangered | Wherever found |
| Phacelia formosula | North Park phacelia | 6 | Endangered | Wherever found |
| Phacelia insularis ssp. insularis | Island phacelia | 8 | Endangered | Wherever found |
| Phacelia submutica | DeBeque phacelia | 6 | Threatened | Wherever found |
| Phlox hirsuta | Yreka phlox | 8 | Endangered | Wherever found |
| Phlox nivalis ssp. texensis | Texas trailing phlox | 2 | Endangered | Wherever found |
| Phyllanthus saffordii | No common name | 1 | Endangered | Wherever found |
| Phyllostegia bracteata | No common name | 1 | Endangered | Wherever found |
| Phyllostegia brevidens | No common name | 1 | Endangered | Wherever found |
| Phyllostegia floribunda | No common name | 1 | Endangered | Wherever found |
| Phyllostegia glabra var. lanaiensis | No common name | 1 | Endangered | Wherever found |
| Phyllostegia haliakalae | No common name | 1 | Endangered | Wherever found |
| Phyllostegia helleri | No common name | 1 | Endangered | Entire |
| Phyllostegia hirsuta | No common name | 1 | Endangered | Wherever found |
| Phyllostegia hispida | No common name | 1 | Endangered | Wherever found |
| Phyllostegia kaalaensis | No common name | 1 | Endangered | Wherever found |
| Phyllostegia knudsenii | No common name | 1 | Endangered | Wherever found |
| Phyllostegia mannii | No common name | 1 | Endangered | Wherever found |
| Phyllostegia mollis | No common name | 1 | Endangered | Wherever found |
| Phyllostegia parviflora | No common name | 1 | Endangered | Wherever found |
| Phyllostegia pilosa | No common name | 1 | Endangered | Wherever found |
| Phyllostegia racemosa | Kiponapona | 1 | Endangered | Wherever found |
| Phyllostegia renovans | No common name | 1 | Endangered | Wherever found |
| Phyllostegia stachyoides | No common name | 1 | Endangered | Wherever found |
| Phyllostegia velutina | No common name | 1 | Endangered | Wherever found |
| Phyllostegia waimeae | No common name | 1 | Endangered | Wherever found |
| Phyllostegia warshaueri | No common name | 1 | Endangered | Wherever found |
| Phyllostegia wawrana | No common name | 1 | Endangered | Wherever found |
| Physaria douglasii ssp. tuplashensis | White Bluffs bladderpod | 1 | Threatened | Wherever found |
| Physaria filiformis | Missouri bladderpod | 3 | Threatened | Wherever found |
| Physaria globosa | Short's bladderpod | 4 | Endangered | Wherever found |
| Physaria obcordata | Dudley Bluffs twinpod | 6 | Threatened | Wherever found |
| Physaria pallida | White bladderpod | 2 | Endangered | Wherever found |
| Physaria thamnophila | Zapata bladderpod | 2 | Endangered | Wherever found |
| Pilosocereus robinii | Key tree cactus | 4 | Endangered | Entire |
| Pinguicula ionantha | Godfrey's butterwort | 4 | Threatened | Entire |
| Piperia yadonii | Yadon's piperia | 8 | Endangered | Wherever found |
| Pittosporum halophilum | Hoawa | 1 | Endangered | Wherever found |
| Pittosporum hawaiiense | Hoawa | 1 | Endangered | Wherever found |
| Pittosporum napaliense | Ho`awa | 1 | Endangered | Wherever found |
| Pityopsis ruthii | Ruth's golden aster | 4 | Endangered | Wherever found |
| Plagiobothrys hirtus | rough popcornflower | 1 | Endangered | Wherever found |
| Plagiobothrys strictus | Calistoga allocarya | 8 | Endangered | Wherever found |
| Plantago hawaiensis | Kuahiwi laukahi | 1 | Endangered | Wherever found |
| Plantago princeps | Kuahiwi laukahi | 1 | Endangered | Wherever found |
| Platanthera holochila | No common name | 1 | Endangered | Wherever found |
| Platanthera integrilabia | White fringeless orchid | 4 | Threatened | Entire |
| Platanthera leucophaea | Eastern prairie fringed orchid | 3 | Threatened | Wherever found |
| Platanthera praeclara | Western prairie fringed Orchid | 3 | Threatened | Wherever found |
| Pleodendron macranthum | Chupacallos | 4 | Endangered | Wherever found |
| Poa atropurpurea | San Bernardino bluegrass | 8 | Endangered | Wherever found |
| Poa mannii | Mann's bluegrass | 1 | Endangered | Wherever found |
| Poa napensis | Napa bluegrass | 8 | Endangered | Wherever found |
| Poa sandvicensis | Hawaiian bluegrass | 1 | Endangered | Wherever found |
| Poa siphonoglossa | No common name | 1 | Endangered | Wherever found |
| Pogogyne abramsii | San Diego mesa-mint | 8 | Endangered | Wherever found |
| Pogogyne nudiuscula | Otay mesa-mint | 8 | Endangered | Wherever found |
| Polygala lewtonii | Lewton's polygala | 4 | Endangered | Entire |
| Polygala smallii | Tiny polygala | 4 | Endangered | Entire |
| Polygonella basiramia | Wireweed | 4 | Endangered | Entire |
| Polygonella myriophylla | Sandlace | 4 | Endangered | Entire |
| Polygonum hickmanii | Scotts Valley Polygonum | 8 | Endangered | Wherever found |
| Polyscias bisattenuata | No common name | 1 | Endangered | Wherever found |
| Polyscias flynnii | No common name | 1 | Endangered | Wherever found |
| Polyscias gymnocarpa | `Ohe`ohe | 1 | Endangered | Wherever found |
| Polyscias lydgatei | No common name | 1 | Endangered | Wherever found |
| Polyscias racemosa | No common name | 1 | Endangered | Wherever found |
| Portulaca sclerocarpa | Po`e | 1 | Endangered | Wherever found |
| Portulaca villosa | Ihi | 1 | Endangered | Wherever found |
| Potamogeton clystocarpus | Little Aguja (=Creek) Pondweed | 2 | Endangered | Wherever found |
| Potentilla hickmanii | Hickman's potentilla | 8 | Endangered | Wherever found |
| Primula maguirei | Maguire primrose | 6 | Threatened | Wherever found |
| Pritchardia aylmer-robinsonii | loulu | 1 | Endangered | Wherever found |
| Pritchardia bakeri | loulu | 1 | Endangered | Wherever found |
| Pritchardia hardyi | loulu | 1 | Endangered | Wherever found |
| Pritchardia kaalae | loulu | 1 | Endangered | Wherever found |
| Pritchardia lanigera | loulu | 1 | Endangered | Wherever found |
| Pritchardia maideniana | loulu | 1 | Endangered | Wherever found |
| Pritchardia munroi | loulu | 1 | Endangered | Wherever found |
| Pritchardia napaliensis | loulu | 1 | Endangered | Wherever found |
| Pritchardia remota | loulu | 1 | Endangered | Wherever found |
| Pritchardia schattaueri | loulu | 1 | Endangered | Wherever found |
| Pritchardia viscosa | loulu | 1 | Endangered | Wherever found |
| Prunus geniculata | Scrub plum | 4 | Endangered | Entire |
| Pseudobahia bahiifolia | Hartweg's golden sunburst | 8 | Endangered | Wherever found |
| Pseudobahia peirsonii | San Joaquin adobe sunburst | 8 | Threatened | Wherever found |
| Pseudognaphalium sandwicensium var. molokaiense | `Ena`ena | 1 | Endangered | Wherever found |
| Psychotria grandiflora | Kopiko | 1 | Endangered | Wherever found |
| Psychotria hexandra var. oahuensis | Kopiko | 1 | Endangered | Wherever found |
| Psychotria hobdyi | Kopiko | 1 | Endangered | Wherever found |
| Psychotria malaspinae | Aplokating-palaoan | 1 | Endangered | Wherever found |
| Pteralyxia kauaiensis | Kaulu | 1 | Endangered | Wherever found |
| Pteralyxia macrocarpa | Kaulu | 1 | Endangered | Wherever found |
| Ptilimnium nodosum | Harperella | 5 | Endangered | Wherever found |
| Purshia (=Cowania) subintegra | Arizona Cliffrose | 2 | Endangered | Wherever found |
| Quercus hinckleyi | Hinckley oak | 2 | Threatened | Wherever found |
| Ranunculus aestivalis (=acriformis) | Autumn Buttercup | 6 | Endangered | Wherever found |
| Ranunculus hawaiensis | Makou | 1 | Endangered | Wherever found |
| Ranunculus mauiensis | Makou | 1 | Endangered | Wherever found |
| Remya kauaiensis | No common name | 1 | Endangered | Wherever found |
| Remya mauiensis | Maui remya | 1 | Endangered | Wherever found |
| Remya montgomeryi | No common name | 1 | Endangered | Wherever found |
| Rhodiola integrifolia ssp. leedyi | Leedy's roseroot | 3 | Threatened | Wherever found |
| Rhododendron chapmanii | Chapman rhododendron | 4 | Endangered | Entire |
| Rhus michauxii | Michaux's sumac | 4 | Endangered | Wherever found |
| Rhynchospora knieskernii | Knieskern's Beaked-rush | 5 | Threatened | Wherever found |
| Ribes echinellum | Miccosukee gooseberry | 4 | Threatened | Entire |
| Rorippa gambellii | Gambel's watercress | 8 | Endangered | Wherever found |
| Sagittaria fasciculata | Bunched arrowhead | 4 | Endangered | Wherever found |
| Sagittaria secundifolia | Kral's water-plantain | 4 | Threatened | Wherever found |
| Sanicula mariversa | No common name | 1 | Endangered | Wherever found |
| Sanicula purpurea | No common name | 1 | Endangered | Wherever found |
| Sanicula sandwicensis | No common name | 1 | Endangered | Wherever found |
| Santalum haleakalae var. lanaiense | Lanai sandalwood (=`iliahi) | 1 | Endangered | Wherever found |
| Santalum involutum | No common name | 1 | Endangered | Wherever found |
| Sarracenia oreophila | Green pitcher-plant | 4 | Endangered | Wherever found |
| Sarracenia rubra ssp. alabamensis | Alabama canebrake pitcher-plant | 4 | Endangered | Wherever found |
| Sarracenia rubra ssp. jonesii | Mountain sweet pitcher-plant | 4 | Endangered | Wherever found |
| Scaevola coriacea | Dwarf naupaka | 1 | Endangered | Wherever found |
| Schenkia sebaeoides | Awiwi | 1 | Endangered | Wherever found |
| Schiedea adamantis | Diamond Head schiedea | 1 | Endangered | Wherever found |
| Schiedea apokremnos | Ma`oli`oli | 1 | Endangered | Wherever found |
| Schiedea attenuata | No common name | 1 | Endangered | Wherever found |
| Schiedea diffusa ssp. macraei | No common name | 1 | Endangered | Wherever found |
| Schiedea diffusa subsp. diffusa | No common name | 1 | Endangered | Wherever found |
| Schiedea haleakalensis | No common name | 1 | Endangered | Wherever found |
| Schiedea hawaiiensis | Ma`oli`oli | 1 | Endangered | Wherever found |
| Schiedea helleri | No common name | 1 | Endangered | Wherever found |
| Schiedea hookeri | No common name | 1 | Endangered | Wherever found |
| Schiedea jacobii | No common name | 1 | Endangered | Wherever found |
| Schiedea kaalae | No common name | 1 | Endangered | Wherever found |
| Schiedea kauaiensis | No common name | 1 | Endangered | Wherever found |
| Schiedea kealiae | Ma`oli`oli | 1 | Endangered | Wherever found |
| Schiedea laui | No common name | 1 | Endangered | Wherever found |
| Schiedea lychnoides | Kuawawaenohu | 1 | Endangered | Wherever found |
| Schiedea lydgatei | No common name | 1 | Endangered | Wherever found |
| Schiedea membranacea | No common name | 1 | Endangered | Wherever found |
| Schiedea nuttallii | No common name | 1 | Endangered | Wherever found |
| Schiedea obovata | No common name | 1 | Endangered | Wherever found |
| Schiedea pubescens | Ma`oli`oli | 1 | Endangered | Wherever found |
| Schiedea salicaria | No common name | 1 | Endangered | Wherever found |
| Schiedea sarmentosa | No common name | 1 | Endangered | Wherever found |
| Schiedea spergulina var. leiopoda | No common name | 1 | Endangered | Wherever found |
| Schiedea spergulina var. spergulina | No common name | 1 | Threatened | Wherever found |
| Schiedea stellarioides | Laulihilihi | 1 | Endangered | Wherever found |
| Schiedea trinervis | No common name | 1 | Endangered | Wherever found |
| Schiedea verticillata | No common name | 1 | Endangered | Wherever found |
| Schiedea viscosa | No common name | 1 | Endangered | Wherever found |
| Schoenocrambe argillacea | Clay reed-mustard | 6 | Threatened | Wherever found |
| Schoenocrambe barnebyi | Barneby reed-mustard | 6 | Endangered | Wherever found |
| Schoenocrambe suffrutescens | Shrubby reed-mustard | 6 | Endangered | Wherever found |
| Schoepfia arenaria | No common name | 4 | Threatened | Wherever found |
| Schwalbea americana | American chaffseed | 4 | Endangered | Wherever found |
| Scirpus ancistrochaetus | Northeastern bulrush | 5 | Endangered | Entire |
| Sclerocactus brevihamatus ssp. tobuschii | Tobusch fishhook cactus | 2 | Threatened | Wherever found |
| Sclerocactus brevispinus | Pariette cactus | 6 | Threatened | Wherever found |
| Sclerocactus glaucus | Colorado hookless Cactus | 6 | Threatened | Wherever found |
| Sclerocactus mariposensis | Lloyd''s Mariposa cactus | 2 | Threatened | Wherever found |
| Sclerocactus mesae-verdae | Mesa Verde cactus | 2 | Threatened | Wherever found |
| Sclerocactus wetlandicus | Uinta Basin hookless cactus | 6 | Threatened | Wherever found |
| Sclerocactus wrightiae | Wright fishhook cactus | 6 | Endangered | Wherever found |
| Scutellaria floridana | Florida skullcap | 4 | Threatened | Entire |
| Scutellaria montana | Large-flowered skullcap | 4 | Threatened | Wherever found |
| Senecio layneae | Layne's butterweed | 8 | Threatened | Wherever found |
| Serianthes nelsonii | Hayun Iagu (=(Guam), Tronkon guafi (Rota)) | 1 | Endangered | Wherever found |
| Sesbania tomentosa | Ohai | 1 | Endangered | Wherever found |
| Sibara filifolia | Santa Cruz Island rockcress | 8 | Endangered | Wherever found |
| Sicyos albus | `Anunu | 1 | Endangered | Wherever found |
| Sicyos lanceoloideus | No common name | 1 | Endangered | Wherever found |
| Sicyos macrophyllus | `Anunu | 1 | Endangered | Wherever found |
| Sidalcea keckii | Keck's Checker-mallow | 8 | Endangered | Wherever found |
| Sidalcea oregana ssp. valida | Kenwood Marsh checker-mallow | 8 | Endangered | Wherever found |
| Sidalcea oregana var. calva | Wenatchee Mountains checkermallow | 1 | Endangered | Wherever found |
| Sidalcea pedata | Pedate checker-mallow | 8 | Endangered | Wherever found |
| Sideroxylon reclinatum ssp. austrofloridense | Everglades bully | 4 | Threatened | Entire |
| Silene alexandri | No common name | 1 | Endangered | Wherever found |
| Silene hawaiiensis | No common name | 1 | Threatened | Wherever found |
| Silene lanceolata | No common name | 1 | Endangered | Wherever found |
| Silene perlmanii | No common name | 1 | Endangered | Wherever found |
| Silene polypetala | Fringed campion | 4 | Endangered | Wherever found |
| Silene spaldingii | Spalding's Catchfly | 1 | Threatened | Wherever found |
| Sisyrinchium dichotomum | White irisette | 4 | Endangered | Wherever found |
| Solanum conocarpum | Marron bacora | 4 | Endangered | Entire |
| Solanum drymophilum | Erubia | 4 | Endangered | Wherever found |
| Solanum guamense | Berenghenas halomtano | 1 | Endangered | Wherever found |
| Solanum incompletum | Popolo ku mai | 1 | Endangered | Wherever found |
| Solanum nelsonii | Popolo | 1 | Endangered | Wherever found |
| Solanum sandwicense | `Aiakeakua, popolo | 1 | Endangered | Wherever found |
| Solidago houghtonii | Houghton's goldenrod | 3 | Threatened | Wherever found |
| Solidago shortii | Short's goldenrod | 4 | Endangered | Wherever found |
| Solidago spithamaea | Blue Ridge goldenrod | 4 | Threatened | Wherever found |
| Spermolepis hawaiiensis | No common name | 1 | Endangered | Wherever found |
| Sphaeralcea gierischii | Gierisch mallow | 2 | Endangered | Wherever found |
| Spigelia gentianoides | Gentian pinkroot | 4 | Endangered | Entire |
| Spiraea virginiana | Virginia spiraea | 5 | Threatened | Wherever found |
| Spiranthes delitescens | Canelo Hills ladies'-tresses | 2 | Endangered | Wherever found |
| Spiranthes diluvialis | Ute ladies'-tresses | 6 | Threatened | Wherever found |
| Spiranthes parksii | Navasota ladies-tresses | 2 | Endangered | Wherever found |
| Stahlia monosperma | Cobana negra | 4 | Threatened | Wherever found |
| Stenogyne angustifolia var. angustifolia | No common name | 1 | Endangered | Wherever found |
| Stenogyne bifida | No common name | 1 | Endangered | Wherever found |
| Stenogyne campanulata | No common name | 1 | Endangered | Wherever found |
| Stenogyne cranwelliae | No common name | 1 | Endangered | Wherever found |
| Stenogyne kaalae ssp. sherffii | No common name | 1 | Endangered | Wherever found |
| Stenogyne kanehoana | No common name | 1 | Endangered | Wherever found |
| Stenogyne kauaulaensis | No common name | 1 | Endangered | Wherever found |
| Stenogyne kealiae | No common name | 1 | Endangered | Wherever found |
| Stephanomeria malheurensis | Malheur wire-lettuce | 1 | Endangered | Wherever found |
| Streptanthus albidus ssp. albidus | Metcalf Canyon jewelflower | 8 | Endangered | Wherever found |
| Streptanthus bracteatus | Bracted twistflower | 2 | Threatened | Wherever found |
| Streptanthus niger | Tiburon jewelflower | 8 | Endangered | Wherever found |
| Styrax platanifolius ssp. texanus | Texas snowbells | 2 | Endangered | Wherever found |
| Styrax portoricensis | Palo de jazmin | 4 | Endangered | Wherever found |
| Suaeda californica | California seablite | 8 | Endangered | Entire |
| Swallenia alexandrae | Eureka Dune grass | 8 | Threatened | Entire |
| Tabernaemontana rotensis | No common name | 1 | Threatened | Wherever found |
| Taraxacum californicum | California taraxacum | 8 | Endangered | Wherever found |
| Ternstroemia luquillensis | Palo colorado | 4 | Endangered | Wherever found |
| Ternstroemia subsessilis | No common name | 4 | Endangered | Wherever found |
| Tetramolopium arenarium | No common name | 1 | Endangered | Wherever found |
| Tetramolopium capillare | Pamakani | 1 | Endangered | Wherever found |
| Tetramolopium filiforme | No common name | 1 | Endangered | Wherever found |
| Tetramolopium lepidotum ssp. lepidotum | No common name | 1 | Endangered | Wherever found |
| Tetramolopium remyi | No common name | 1 | Endangered | Wherever found |
| Tetramolopium rockii | No common name | 1 | Threatened | Wherever found |
| Thalictrum cooleyi | Cooley's meadowrue | 4 | Endangered | Wherever found |
| Thelypodium howellii ssp. spectabilis | Howell''s spectacular thelypody | 1 | Threatened | Wherever found |
| Thelypodium stenopetalum | Slender-petaled mustard | 8 | Endangered | Wherever found |
| Thlaspi californicum | Kneeland Prairie penny-cress | 8 | Endangered | Wherever found |
| Thymophylla tephroleuca | Ashy dogweed | 2 | Endangered | Wherever found |
| Thysanocarpus conchuliferus | Santa Cruz Island fringepod | 8 | Endangered | Wherever found |
| Tinospora homosepala | No common name | 1 | Endangered | Wherever found |
| Townsendia aprica | Last Chance townsendia | 6 | Threatened | Wherever found |
| Trematolobelia singularis | No common name | 1 | Endangered | Wherever found |
| Trichilia triacantha | Bariaco | 4 | Endangered | Wherever found |
| Trifolium amoenum | Showy Indian clover | 8 | Endangered | Wherever found |
| Trifolium trichocalyx | Monterey clover | 8 | Endangered | Wherever found |
| Trillium persistens | Persistent trillium | 4 | Endangered | Wherever found |
| Trillium reliquum | Relict trillium | 4 | Endangered | Wherever found |
| Tuberolabium guamense | No common name | 1 | Threatened | Wherever found |
| Tuctoria greenei | Greene's tuctoria | 8 | Endangered | Wherever found |
| Tuctoria mucronata | Solano grass | 8 | Endangered | Wherever found |
| Urera kaalae | Opuhe | 1 | Endangered | Wherever found |
| Varronia rupicola | No common name | 4 | Threatened | Wherever found |
| Verbena californica | Red Hills vervain | 8 | Threatened | Wherever found |
| Verbesina dissita | Big-leaved crownbeard | 8 | Threatened | Wherever found |
| Vernonia proctorii | No common name | 4 | Endangered | Wherever found |
| Vicia menziesii | Hawaiian vetch | 1 | Endangered | Wherever found |
| Vigna o-wahuensis | No common name | 1 | Endangered | Wherever found |
| Viola chamissoniana ssp. chamissoniana | Pamakani | 1 | Endangered | Wherever found |
| Viola helenae | No common name | 1 | Endangered | Wherever found |
| Viola kauaiensis var. wahiawaensis | Nani wai`ale`ale | 1 | Endangered | Wherever found |
| Viola lanaiensis | No common name | 1 | Endangered | Wherever found |
| Viola oahuensis | No common name | 1 | Endangered | Wherever found |
| Warea amplexifolia | Wide-leaf warea | 4 | Endangered | Entire |
| Warea carteri | Carter's mustard | 4 | Endangered | Entire |
| Wikstroemia skottsbergiana | No common name | 1 | Endangered | Entire |
| Wikstroemia villosa | No common name | 1 | Endangered | Wherever found |
| Wilkesia hobdyi | Dwarf iliau | 1 | Endangered | Wherever found |
| Xylosma crenatum | No common name | 1 | Endangered | Wherever found |
| Xyris tennesseensis | Tennessee yellow-eyed grass | 4 | Endangered | Wherever found |
| Yermo xanthocephalus | Desert yellowhead | 6 | Threatened | Wherever found |
| Zanthoxylum dipetalum var. tomentosum | A`e | 1 | Endangered | Wherever found |
| Zanthoxylum hawaiiense | A`e | 1 | Endangered | Wherever found |
| Zanthoxylum oahuense | A`e | 1 | Endangered | Wherever found |
| Zanthoxylum thomasianum | St. Thomas prickly-ash | 4 | Endangered | Wherever found |
| Zizania texana | Texas wild-rice | 2 | Endangered | Wherever found |
| Ziziphus celata | Florida ziziphus | 4 | Endangered | Entire |