| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| USMU | Usnea mutabilis Stirton | beard lichen | Parmeliaceae
|
| USNA | Usnea nashii P. Clerc & Herrera-Campos | beard lichen | Parmeliaceae
|
| USOC | Usnea occidentalis Mot. | western beard lichen | Parmeliaceae
|
| USPA | Usnea pachyclada Mot. | beard lichen | Parmeliaceae
|
| USPE | Usnea pensylvanica Mot. | Pennsylvania beard lichen | Parmeliaceae
|
| USPE3 | Usnea perplectata Mot. | beard lichen | Parmeliaceae
|
| USPE2 | Usnea perplexans Striton | perplexed beard lichen | Parmeliaceae
|
| USRA | Usnea ramillosa Mot. | beard lichen | Parmeliaceae
|
| USRE | Usnea retifera Mot. | beard lichen | Parmeliaceae
|
| USRO | Usnea roseola Vainio | beard lichen | Parmeliaceae
|
| USRU | Usnea rubicunda Stirton | beard lichen | Parmeliaceae
|
| USRU2 | Usnea rubiginea (Michaux) A. Massal. | Usnea strigosa ssp. rubiginea | Parmeliaceae
|
| USRU3 | Usnea rugulosa Vainio | Usnea scabrata | Parmeliaceae
|
| USSA | Usnea sacbiosa Mot. | beard lichen | Parmeliaceae
|
| USSCN | Usnea scabrata Nyl. ssp. nylanderiana Mot. | Usnea scabrata | Parmeliaceae
|
| USSC2 | Usnea scabrata Nyl. | beard lichen | Parmeliaceae
|
| USSC61 | Usnea scholanderi Llano | Scholander's beard lichen | Parmeliaceae
|
| USSI2 | Usnea silvatica Mot. | beard lichen | Parmeliaceae
|
| USSI | Usnea similis Mot. ex Rasanen | Usnea subfloridana | Parmeliaceae
|
| USSO | Usnea sorediifera (Arnold) Lynge | Usnea glabrata | Parmeliaceae
|
| USSO2 | Usnea sorediifera sensu Mot. | Usnea lapponica | Parmeliaceae
|
| USSP | Usnea sphacelata R. Br. | beard lichen | Parmeliaceae
|
| USSP2 | Usnea spinulifera (Vainio) Mot. | Usnea dasaea | Parmeliaceae
|
| USSTM | Usnea strigosa (Ach.) Eaton ssp. major (Michaux) I. Tav. | strigose beard lichen | Parmeliaceae
|
| USSTR | Usnea strigosa (Ach.) Eaton ssp. rubiginea (Michaux) I. Tav. | strigose beard lichen | Parmeliaceae
|
| USSTS | Usnea strigosa (Ach.) Eaton ssp. strigosa | strigose beard lichen | Parmeliaceae
|
| USST2 | Usnea strigosa (Ach.) Eaton | strigose beard lichen | Parmeliaceae
|
| USST | Usnea stuppea (Rasanen) Mot. | beard lichen | Parmeliaceae
|
| USSU7 | Usnea subcariosa Mot. | beard lichen | Parmeliaceae
|
| USSU2 | Usnea subcavata Mot. | Usnea perplectata | Parmeliaceae
|
| USSU60 | Usnea subfloridana Stirton | beard lichen | Parmeliaceae
|
| USSU3 | Usnea subfusca Stirton | beard lichen | Parmeliaceae
|
| USSU4 | Usnea subhirta Mot. | beard lichen | Parmeliaceae
|
| USSU61 | Usnea sublaxa Vainio | Usnea filipendula | Parmeliaceae
|
| USSU5 | Usnea subscabrosa Mot. | beard lichen | Parmeliaceae
|
| USSU6 | Usnea substerilis Mot. | beard lichen | Parmeliaceae
|
| USSY | Usnea sylvatica Mot. | beard lichen | Parmeliaceae
|
| USTR | Usnea trichodea Ach. | beard lichen | Parmeliaceae
|
| USTR2 | Usnea tristis Mot. | beard lichen | Parmeliaceae
|
| USVA | Usnea vainioi Mot. | beard lichen | Parmeliaceae
|
| USVA2 | Usnea variegata Stirton | varigated beard lichen | Parmeliaceae
|
| USVA3 | Usnea variolosa Mot. | Usnea hirta | Parmeliaceae
|
| USWA | Usnea wasmuthii Rasanen | beard lichen | Parmeliaceae
|
| USWI | Usnea wirthii P. Clerc | Wirth's beard lichen | Parmeliaceae
|
| USXA | Usnea xanthopoga Nyl. | beard lichen | Parmeliaceae
|
| USNEA2 | Usnea Dill. ex Adans. | beard lichen | Parmeliaceae
|
| UTAM | Utricularia amethystina Salzm. ex St.-Hil. & Girard | Florida purple bladderwort | Lentibulariaceae
|
| UTBI2 | Utricularia bifida L. | bladderwort | Lentibulariaceae
|
| UTBI | Utricularia biflora Lam. | Utricularia gibba | Lentibulariaceae
|
| UTCA | Utricularia caerulea L. | bladderwort | Lentibulariaceae
|
| UTCL | Utricularia cleistogama (Gray) Britt. | Utricularia subulata | Lentibulariaceae
|
| UTCO | Utricularia cornuta Michx. | horned bladderwort | Lentibulariaceae
|
| UTEX | Utricularia exoleta R.Br. | bladderwort | Lentibulariaceae
|
| UTFI3 | Utricularia fibrosa Britt. | Utricularia striata | Lentibulariaceae
|
| UTFI | Utricularia fibrosa Walt. | Utricularia gibba | Lentibulariaceae
|
| UTFI2 | Utricularia fimbriata auct. non Kunth | Utricularia simulans | Lentibulariaceae
|
| UTFL | Utricularia floridana Nash | Florida yellow bladderwort | Lentibulariaceae
|
| UTFO | Utricularia foliosa L. | leafy bladderwort | Lentibulariaceae
|
| UTGE | Utricularia geminiscapa Benj. | hiddenfruit bladderwort | Lentibulariaceae
|
| UTGI | Utricularia gibba L. | humped bladderwort | Lentibulariaceae
|
| UTINM | Utricularia inflata Walt. var. minor Chapman | Utricularia radiata | Lentibulariaceae
|
| UTIN | Utricularia inflata Walt. | swollen bladderwort | Lentibulariaceae
|
| UTIN2 | Utricularia intermedia Hayne | flatleaf bladderwort | Lentibulariaceae
|
| UTJU | Utricularia juncea Vahl | southern bladderwort | Lentibulariaceae
|
| UTMA | Utricularia macrorhiza Le Conte | common bladderwort | Lentibulariaceae
|
| UTMI | Utricularia minor L. | lesser bladderwort | Lentibulariaceae
|
| UTMI2 | Utricularia mixta Barnh. | Utricularia foliosa | Lentibulariaceae
|
| UTOB | Utricularia obtusa Sw. | Utricularia gibba | Lentibulariaceae
|
| UTOC2 | Utricularia occidentalis Gray | Utricularia ochroleuca | Lentibulariaceae
|
| UTOC | Utricularia ochroleuca R.W. Hartman | yellowishwhite bladderwort | Lentibulariaceae
|
| UTOL | Utricularia olivacea C. Wright ex Griseb. | piedmont bladderwort | Lentibulariaceae
|
| UTPU3 | Utricularia pumila Walt. | Utricularia gibba | Lentibulariaceae
|
| UTPU | Utricularia purpurea Walt. | eastern purple bladderwort | Lentibulariaceae
|
| UTPU2 | Utricularia pusilla Vahl | tiny bladderwort | Lentibulariaceae
|
| UTRA2 | Utricularia racemosa Wallich | bladderwort | Lentibulariaceae
|
| UTRA | Utricularia radiata Small | little floating bladderwort | Lentibulariaceae
|
| UTRE | Utricularia resupinata B.D. Greene ex Bigelow | lavender bladderwort | Lentibulariaceae
|
| UTSI | Utricularia simulans Pilger | fringed bladderwort | Lentibulariaceae
|
| UTST | Utricularia striata Le Conte ex Torrey | striped bladderwort | Lentibulariaceae
|
| UTSU | Utricularia subulata L. | zigzag bladderwort | Lentibulariaceae
|
| UTUL | Utricularia uliginosa Vahl | bladderwort | Lentibulariaceae
|
| UTVI | Utricularia virgatula Barnh. | Utricularia juncea | Lentibulariaceae
|
| UTVUM | Utricularia vulgaris L. ssp. macrorhiza (Le Conte) Clausen | Utricularia macrorhiza | Lentibulariaceae
|
| UTVUA | Utricularia vulgaris L. var. americana Gray | Utricularia macrorhiza | Lentibulariaceae
|
| UTVU | Utricularia vulgaris L. p.p. | Utricularia macrorhiza | Lentibulariaceae
|
| UTRIC | Utricularia L. | bladderwort | Lentibulariaceae
|
| UVUV | Uva-Ursi uva-ursi (L.) Britt. | Arctostaphylos uva-ursi | Ericaceae
|
| UVOD | Uvaria odorata Lam. | Cananga odorata | Annonaceae
|
| UVAM | Uvularia amplexifolia L. | Streptopus amplexifolius var. amplexifolius | Liliaceae
|
| UVCA | Uvularia carolina (J.F. Gmel.) Wilbur | Uvularia puberula | Liliaceae
|
| UVFL | Uvularia floridana Chapman | Florida bellwort | Liliaceae
|
| UVGR | Uvularia grandiflora Sm. | largeflower bellwort | Liliaceae
|
| UVNI | Uvularia nitida (Britt.) Mackenzie | Uvularia puberula | Liliaceae
|
| UVPE | Uvularia perfoliata L. | perfoliate bellwort | Liliaceae
|
| UVPUN2 | Uvularia puberula Michx. var. nitida (Britt.) Fern. | Uvularia puberula | Liliaceae
|
| UVPU2 | Uvularia puberula Michx. | mountain bellwort | Liliaceae
|
| UVPUN | Uvularia pudica Fern. var. nitida (Britt.) Fern. | Uvularia puberula | Liliaceae
|
| UVPU3 | Uvularia pudica sensu Fern. | Uvularia puberula | Liliaceae
|
| UVSE | Uvularia sessilifolia L. | sessileleaf bellwort | Liliaceae
|
| UVSM | Uvularia smithii Hook. | Disporum smithii | Liliaceae
|
| UVULA | Uvularia L. | bellwort | Liliaceae
|