| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| TRLA | Tragia laciniata (Torr.) Muell.-Arg. | Sonoita noseburn | Euphorbiaceae
|
| TRLE9 | Tragia leptophylla (Torr.) I.M. Johnston | fineleaf noseburn | Euphorbiaceae
|
| TRLI2 | Tragia linearifolia Ell. | Tragia urens | Euphorbiaceae
|
| TRMA10 | Tragia macrocarpa Willd. | Tragia cordata | Euphorbiaceae
|
| TRNED | Tragia nepetifolia Cav. var. dissecta Muell.-Arg. | catnip noseburn | Euphorbiaceae
|
| TRNEL | Tragia nepetifolia Cav. var. leptophylla (Torr.) Shinners | Tragia leptophylla | Euphorbiaceae
|
| TRNER | Tragia nepetifolia Cav. var. ramosa (Torr.) Muell.-Arg. | Tragia ramosa | Euphorbiaceae
|
| TRNE | Tragia nepetifolia Cav. | catnip noseburn | Euphorbiaceae
|
| TRNI | Tragia nigricans Bush | dark noseburn | Euphorbiaceae
|
| TRRAL | Tragia ramosa Torr. var. leptophylla Torr. | Tragia leptophylla | Euphorbiaceae
|
| TRRA5 | Tragia ramosa Torr. | branched noseburn | Euphorbiaceae
|
| TRSA2 | Tragia saxicola Small | Florida Keys noseburn | Euphorbiaceae
|
| TRSM | Tragia smallii Shinners | Small's noseburn | Euphorbiaceae
|
| TRST10 | Tragia stylaris Muell.-Arg. | Tragia ramosa | Euphorbiaceae
|
| TRUR | Tragia urens L. | wavyleaf noseburn | Euphorbiaceae
|
| TRURT | Tragia urticifolia Michx. var. texana Shinners | Tragia betonicifolia | Euphorbiaceae
|
| TRUR2 | Tragia urticifolia Michx. | nettleleaf noseburn | Euphorbiaceae
|
| TRVO | Tragia volubilis L. | fireman | Euphorbiaceae
|
| TRAGI | Tragia L. | noseburn | Euphorbiaceae
|
| TRPIE | Tragiola pilosa (Michx.) Small & Pennell ssp. epilis (Pennell) Pennell | Gratiola pilosa | Scrophulariaceae
|
| TRPI7 | Tragiola pilosa (Michx.) Small & Pennell | Gratiola pilosa | Scrophulariaceae
|
| TRCR10 | Tragopogon �crantzii Dichlt. | | Asteraceae
|
| TRDUM | Tragopogon dubius Scop. ssp. major (Jacq.) Voll. | Tragopogon dubius | Asteraceae
|
| TRDU | Tragopogon dubius Scop. | yellow salsify | Asteraceae
|
| TRFL15 | Tragopogon floccosus Waldst. & Kit. | woolly goatsbeard | Asteraceae
|
| TRMA9 | Tragopogon major Jacq. | Tragopogon dubius | Asteraceae
|
| TRMI10 | Tragopogon mirabilis Rouy | Ontario goatsbeard | Asteraceae
|
| TRMI7 | Tragopogon mirus Ownbey | remarkable goatsbeard | Asteraceae
|
| TRMI8 | Tragopogon miscellus Ownbey | Moscow salsify | Asteraceae
|
| TRNE7 | Tragopogon �neohybridus Farw. | | Asteraceae
|
| TRPO | Tragopogon porrifolius L. | salsify | Asteraceae
|
| TRPR | Tragopogon pratensis L. | Jack-go-to-bed-at-noon | Asteraceae
|
| TRAGO | Tragopogon L. | goatsbeard | Asteraceae
|
| TRAU11 | Tragus australianus S.T. Blake | Australian burr grass | Poaceae
|
| TRBE | Tragus berteronianus J.A. Schultes | spiked burr grass | Poaceae
|
| TRHE8 | Tragus heptaneuron W.D. Clayton | Kenya burr grass | Poaceae
|
| TRRA | Tragus racemosus (L.) All. | stalked burr grass | Poaceae
|
| TRAGU | Tragus Haller | burr grass | Poaceae
|
| TRBI5 | Trapa bicornis Osbeck | horn nut | Trapaceae
|
| TRBI6 | Trapa bispinosa Roxb. | Trapa natans var. bispinosa | Trapaceae
|
| TRNAB | Trapa natans L. var. bispinosa (Roxb.) Makino | singhara nut | Trapaceae
|
| TRNAN | Trapa natans L. var. natans | caltrop | Trapaceae
|
| TRNA | Trapa natans L. | water chestnut | Trapaceae
|
| TRAPA | Trapa L. | water chestnut | Trapaceae
|
| TRBR10 | Trapelia brujeriana (D. Dietr.) Choisy | Trapelia mooreana | Trapeliaceae
|
| TRCO13 | Trapelia coarctata (Sm.) Choisy | disk lichen | Trapeliaceae
|
| TRCO17 | Trapelia corticola Coppins & P. James | disk lichen | Trapeliaceae
|
| TRIN12 | Trapelia involuta (Taylor) Hertel | disk lichen | Trapeliaceae
|
| TRMO14 | Trapelia mooreana (Carroll) P. James | disk lichen | Trapeliaceae
|
| TROB4 | Trapelia obtegens (Th. Fr.) Hertel | disk lichen | Trapeliaceae
|
| TRPL5 | Trapelia placodioides Coppins & P. James | disk lichen | Trapeliaceae
|
| TRTO2 | Trapelia torellii (Anzi) Hertel | Trapelia mooreana | Trapeliaceae
|
| TRAPE | Trapelia Choisy | disk lichen | Trapeliaceae
|
| TRAE6 | Trapeliopsis aeneofusca (Flotow) Coppins & P. James | | Trapeliaceae
|
| TRFL11 | Trapeliopsis flexuosa (Fr.) Coppins & P. James | | Trapeliaceae
|
| TRGE4 | Trapeliopsis gelatinosa (Florke) Coppins & P. James | | Trapeliaceae
|
| TRGR14 | Trapeliopsis granulosa (Hoffm.) Lumbsch | | Trapeliaceae
|
| TRPS | Trapeliopsis pseudogranulosa Coppins & P. James | | Trapeliaceae
|
| TRVI8 | Trapeliopsis viridescens (Schrader) Coppins & P. James | | Trapeliaceae
|
| TRWA3 | Trapeliopsis wallrothii (Florke) Hertel & Gotth. Schneider | | Trapeliaceae
|
| TRAPE2 | Trapeliopsis Hertel & Gotth. Schneider | trapeliopsis | Trapeliaceae
|
| TRCAC2 | Trautvetteria caroliniensis (Walt.) Vail var. caroliniensis | Carolina bugbane | Ranunculaceae
|
| TRCAO | Trautvetteria caroliniensis (Walt.) Vail var. occidentalis (Gray) C.L. Hitchc. | western bugbane | Ranunculaceae
|
| TRCA | Trautvetteria caroliniensis (Walt.) Vail | Carolina bugbane | Ranunculaceae
|
| TRGR10 | Trautvetteria grandis Nutt. | Trautvetteria caroliniensis var. occidentalis | Ranunculaceae
|
| TRAUT | Trautvetteria Fisch. & C.A. Mey. | bugbane | Ranunculaceae
|
| TRAF2 | Treculia africana Decne. ex Trec. | African breadfruit | Moraceae
|
| TRECU | Treculia Decne. ex Trec. | treculia | Moraceae
|
| TRFL9 | Trema floridanum Britt. | Trema micranthum | Ulmaceae
|
| TRLA2 | Trema lamarckianum (J.A. Schultes) Blume | Lamarck's trema | Ulmaceae
|
| TRMI2 | Trema micranthum (L.) Blume | Jamaican nettletree | Ulmaceae
|
| TROR | Trema orientale (L.) Blume | oriental trema | Ulmaceae
|
| TREMA | Trema Lour. | trema | Ulmaceae
|
| TRAM16 | Trematodon ambiguus (Hedw.) Hornsch. | ambiguous trematodon moss | Bruchiaceae
|
| TRBO8 | Trematodon boasii Schof. | Boas' trematodon moss | Bruchiaceae
|
| TRBR11 | Trematodon brevicollis Hoppe & Hornsch. ex Hornsch. | trematodon moss | Bruchiaceae
|
| TRLO7 | Trematodon longicollis Michx. | trematodon moss | Bruchiaceae
|
| TRMO15 | Trematodon montanus Belland & Brass. | montane trematodon moss | Bruchiaceae
|
| TREMA3 | Trematodon Michx. | trematodon moss | Bruchiaceae
|
| TRGR8 | Trematolobelia grandifolia (Rock) O. Deg. | largeflower false lobelia | Campanulaceae
|
| TRKA2 | Trematolobelia kauaiensis (Rock) Skottsberg | Kauai false lobelia | Campanulaceae
|
| TRMAH | Trematolobelia macrostachys (Hook. & Arn.) Zahlbr. var. haleakalaensis St. John | Trematolobelia macrostachys | Campanulaceae
|
| TRMA8 | Trematolobelia macrostachys (Hook. & Arn.) Zahlbr. | koli'i | Campanulaceae
|
| TRSI5 | Trematolobelia singularis St. John | lavaslope false lobelia | Campanulaceae
|
| TRWI2 | Trematolobelia wimmeri O.& I. Deg. | Trematolobelia grandifolia | Campanulaceae
|
| TREMA2 | Trematolobelia Zahlbr. ex Rock | false lobelia | Campanulaceae
|
| TRPHP | Trembleya phlogiformis DC. var. parvifolia Cogn. | island glorybush | Melastomataceae
|
| TRPH | Trembleya phlogiformis DC. | island glorybush | Melastomataceae
|
| TREMB | Trembleya DC. | trembleya | Melastomataceae
|
| TRCE7 | Tremella cetrariicola Diederich & Coppins | Witch's butter | Tremellaceae
|
| TRCL5 | Tremella cladoniae Diederich & M. S. Christ. | Witch's butter | Tremellaceae
|
| TRDE7 | Tremella dendrographae Diederich & Tehler | Witch's butter | Tremellaceae
|
| TREV | Tremella everniae Diederich | Witch's butter | Tremellaceae
|
| TRHA4 | Tremella haematommatis Diederich | Witch's butter | Tremellaceae
|
| TRHA5 | Tremella harrisii Diederich | Witch's butter | Tremellaceae
|
| TRHY6 | Tremella hypogymniae Diederich & M. S. Christ. | Witch's butter | Tremellaceae
|
| TRLI9 | Tremella lichenicola Diederich | Witch's butter | Tremellaceae
|
| TRNE9 | Tremella nephromatis Diederich | Witch's butter | Tremellaceae
|
| TRPA25 | Tremella parmeliarum Diederich | Witch's butter | Tremellaceae
|
| TRPE23 | Tremella pertusariae Diederich | Witch's butter | Tremellaceae
|
| TRPH6 | Tremella phaeographinae Diederich & Aptroot | Witch's butter | Tremellaceae
|