| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| TICAP | Tiquilia canescens (DC.) A. Richards. var. pulchella (I.M. Johnston) A. Richards. | woody crinklemat | Boraginaceae
|
| TICA3 | Tiquilia canescens (DC.) A. Richards. | woody crinklemat | Boraginaceae
|
| TIGO | Tiquilia gossypina (Woot. & Standl.) A. Richards. | Texas crinklemat | Boraginaceae
|
| TIGR | Tiquilia greggii (Torr. & Gray) A. Richards. | plumed crinklemat | Boraginaceae
|
| TIHI | Tiquilia hispidissima (Torr. & Gray) A. Richards. | hairy crinklemat | Boraginaceae
|
| TILA6 | Tiquilia latior (I.M. Johnston) A. Richards. | matted crinklemat | Boraginaceae
|
| TIME | Tiquilia mexicana (S. Wats.) A. Richards. | Mexican crinklemat | Boraginaceae
|
| TINU2 | Tiquilia nuttallii (Hook.) A. Richards. | Nuttall's crinklemat | Boraginaceae
|
| TIPA | Tiquilia palmeri (Gray) A. Richards. | Palmer's crinklemat | Boraginaceae
|
| TIPL2 | Tiquilia plicata (Torr.) A. Richards. | fanleaf crinklemat | Boraginaceae
|
| TIQUI | Tiquilia Pers. | crinklemat | Boraginaceae
|
| TIPA3 | Tiquiliopsis palmeri (Gray) Rydb. | Tiquilia palmeri | Boraginaceae
|
| TICA4 | Tissa canadensis (Pers.) Britt. | Spergularia canadensis var. canadensis | Caryophyllaceae
|
| TICL | Tissa clevelandii Greene | Spergularia villosa | Caryophyllaceae
|
| TILU | Tissa luteola Greene | Spergularia bocconii | Caryophyllaceae
|
| TIMA | Tissa marina (L.) Britt. | Spergularia salina | Caryophyllaceae
|
| TIRU | Tissa rubra (L.) Britt. | Spergularia rubra | Caryophyllaceae
|
| TITE3 | Tissa tenuis Greene | Spergularia salina | Caryophyllaceae
|
| TIAR4 | Tithonia argophylla D.C. Eat. | Enceliopsis argophylla | Asteraceae
|
| TIDI2 | Tithonia diversifolia (Hemsl.) Gray | tree marigold | Asteraceae
|
| TIRO | Tithonia rotundifolia (P. Mill.) Blake | clavel de muerto | Asteraceae
|
| TISP2 | Tithonia speciosa (Hook.) Griseb. | Tithonia rotundifolia | Asteraceae
|
| TITH | Tithonia thurberi Gray | Arizona sunflowerweed | Asteraceae
|
| TITHO | Tithonia Desf. ex Juss. | tithonia | Asteraceae
|
| TIAP | Tithymalopsis apocynifolia (Small) Small | Euphorbia pubentissima | Euphorbiaceae
|
| TIAR2 | Tithymalopsis arundelana (Bartlett) Small | Euphorbia ipecacuanhae | Euphorbiaceae
|
| TICO4 | Tithymalopsis corollata (L.) Klotzsch | Euphorbia corollata | Euphorbiaceae
|
| TICU | Tithymalopsis curtisii (Engelm.) Small | Euphorbia curtisii | Euphorbiaceae
|
| TIDI3 | Tithymalopsis discoidalis (Chapman) Small | Euphorbia discoidalis | Euphorbiaceae
|
| TIER2 | Tithymalopsis eriogonoides Small | Euphorbia curtisii | Euphorbiaceae
|
| TIEX | Tithymalopsis exserta Small | Euphorbia exserta | Euphorbiaceae
|
| TIGR2 | Tithymalopsis gracilis (Boiss.) Small | Euphorbia exserta | Euphorbiaceae
|
| TIIP | Tithymalopsis ipecacuanhae (L.) Small | Euphorbia ipecacuanhae | Euphorbiaceae
|
| TIMA2 | Tithymalopsis marilandica (Greene) Small | Euphorbia corollata | Euphorbiaceae
|
| TIME3 | Tithymalopsis mercurialina (Michx.) Small | Euphorbia mercurialina | Euphorbiaceae
|
| TIOL | Tithymalopsis olivacea Small | Euphorbia corollata | Euphorbiaceae
|
| TIPA4 | Tithymalopsis paniculata (Boiss.) Small | Euphorbia pubentissima | Euphorbiaceae
|
| TIPO3 | Tithymalopsis polyphylla (Engelm. ex Chapman) Small | Euphorbia polyphylla | Euphorbiaceae
|
| TIST | Tithymalopsis strictior (Holz.) Woot. & Standl. | Euphorbia strictior | Euphorbiaceae
|
| TIZI | Tithymalopsis zinniiflora (Small) Small | Euphorbia pubentissima | Euphorbiaceae
|
| TIAR3 | Tithymalus arkansanus (Engelm. & Gray) Klotzsch & Garcke | Euphorbia spathulata | Euphorbiaceae
|
| TIAU | Tithymalus austrinus Small | Euphorbia segetalis | Euphorbiaceae
|
| TIBR | Tithymalus brachycera (Engelm.) Small | Euphorbia brachycera | Euphorbiaceae
|
| TICH | Tithymalus chamaesula (Boiss.) Woot. & Standl. | Euphorbia chamaesula | Euphorbiaceae
|
| TICO3 | Tithymalus commutatus (Engelm.) Klotzsch & Garcke | Euphorbia commutata | Euphorbiaceae
|
| TICR | Tithymalus crenulatus (Engelm.) Heller | Euphorbia crenulata | Euphorbiaceae
|
| TICY | Tithymalus cyparissias (L.) Hill | Euphorbia cyparissias | Euphorbiaceae
|
| TIDA | Tithymalus darlingtonii (Gray) Small | Euphorbia purpurea | Euphorbiaceae
|
| TIES | Tithymalus esula (L.) Hill | Euphorbia esula var. esula | Euphorbiaceae
|
| TIFA2 | Tithymalus falcatus (L.) Klotzsch & Garcke | Euphorbia falcata | Euphorbiaceae
|
| TIHE3 | Tithymalus helioscopius (L.) Hill | Euphorbia helioscopia | Euphorbiaceae
|
| TIINM | Tithymalus incisa (Engelm.) J.B.S. Norton var. mollis J.B.S. Norton | Euphorbia incisa var. mollis | Euphorbiaceae
|
| TIIN2 | Tithymalus incisa (Engelm.) J.B.S. Norton | Euphorbia incisa var. incisa | Euphorbiaceae
|
| TILA3 | Tithymalus lathyris (L.) Hill | Euphorbia lathyris | Euphorbiaceae
|
| TILU2 | Tithymalus lucidus (Waldst. & Kit.) Klotzsch & Garcke | Euphorbia lucida | Euphorbiaceae
|
| TIMI2 | Tithymalus missouriensis (J.B.S. Norton) Small | Euphorbia spathulata | Euphorbiaceae
|
| TIMO | Tithymalus montanus (Engelm.) Small | Euphorbia brachycera | Euphorbiaceae
|
| TIMY2 | Tithymalus myrsinites (L.) Hill | Euphorbia myrsinites | Euphorbiaceae
|
| TIOB2 | Tithymalus obtusatus (Pursh) Klotzsch & Garcke | Euphorbia spathulata | Euphorbiaceae
|
| TIPE2 | Tithymalus peplus (L.) Hill | Euphorbia peplus | Euphorbiaceae
|
| TIPL3 | Tithymalus platyphyllos (L.) Hill | Euphorbia platyphyllos | Euphorbiaceae
|
| TIRO2 | Tithymalus robustus (Engelm.) Small | Euphorbia brachycera | Euphorbiaceae
|
| TISM2 | Tithymalus smallii (Millsp.) Small | Pedilanthus tithymaloides ssp. smallii | Euphorbiaceae
|
| TISP | Tithymalus spathulatus (Lam.) W.A. Weber | Euphorbia spathulata | Euphorbiaceae
|
| TITE4 | Tithymalus texanus Millsp. ex Heller | Euphorbia texana | Euphorbiaceae
|
| TIUR2 | Tithymalus uralensis (Fisch. ex Link) Prokhanov | Euphorbia esula var. uralensis | Euphorbiaceae
|
| TIDR3 | Tium drummondii (Dougl. ex Hook.) Rydb. | Astragalus drummondii | Fabaceae
|
| TIMI3 | Tium michauxii (Kuntze) Rydb. | Astragalus michauxii | Fabaceae
|
| TOCO | Tofieldia coccinea Richards. | northern asphodel | Liliaceae
|
| TOGL | Tofieldia glabra Nutt. | smooth tofieldia | Liliaceae
|
| TOGLA2 | Tofieldia glutinosa (Michx.) Pers. ssp. absona C.L. Hitchc. | Priest Lake tofieldia | Liliaceae
|
| TOGLB | Tofieldia glutinosa (Michx.) Pers. ssp. brevistyla C.L. Hitchc. | sticky tofieldia | Liliaceae
|
| TOGLG | Tofieldia glutinosa (Michx.) Pers. ssp. glutinosa | sticky tofieldia | Liliaceae
|
| TOGLM2 | Tofieldia glutinosa (Michx.) Pers. ssp. montana C.L. Hitchc. | sticky tofieldia | Liliaceae
|
| TOGLO2 | Tofieldia glutinosa (Michx.) Pers. ssp. occidentalis (S. Wats.) C.L. Hitchc. | western tofieldia | Liliaceae
|
| TOGLA | Tofieldia glutinosa (Michx.) Pers. var. absona (C.L. Hitchc.) R.J. Davis | Tofieldia glutinosa ssp. absona | Liliaceae
|
| TOGLB2 | Tofieldia glutinosa (Michx.) Pers. var. brevistyla (C.L. Hitchc.) C.L. Hitchc. | Tofieldia glutinosa ssp. brevistyla | Liliaceae
|
| TOGLI | Tofieldia glutinosa (Michx.) Pers. var. intermedia (Rydb.) Boivin | Tofieldia glutinosa ssp. brevistyla | Liliaceae
|
| TOGLM | Tofieldia glutinosa (Michx.) Pers. var. montana (C.L. Hitchc.) R.J. Davis | Tofieldia glutinosa ssp. montana | Liliaceae
|
| TOGLO | Tofieldia glutinosa (Michx.) Pers. var. occidentalis (S. Wats.) C.L. Hitchc. | Tofieldia glutinosa ssp. occidentalis | Liliaceae
|
| TOGL2 | Tofieldia glutinosa (Michx.) Pers. | sticky tofieldia | Liliaceae
|
| TOOC | Tofieldia occidentalis S. Wats. | Tofieldia glutinosa ssp. occidentalis | Liliaceae
|
| TOPA4 | Tofieldia palustris auct. non Huds. | Tofieldia pusilla | Liliaceae
|
| TOPU | Tofieldia pusilla (Michx.) Pers. | Scotch false asphodel | Liliaceae
|
| TORAG | Tofieldia racemosa (Walt.) B.S.P. var. glutinosa (Michx.) Ahles | Tofieldia glutinosa ssp. glutinosa | Liliaceae
|
| TORA | Tofieldia racemosa (Walt.) B.S.P. | coastal false asphodel | Liliaceae
|
| TOTE3 | Tofieldia tenuifolia (Michx.) Utech | Pleea tenuifolia | Liliaceae
|
| TOFIE | Tofieldia Huds. | tofieldia | Liliaceae
|
| TOIN3 | Tolmachevia integrifolia (Raf.) A.& D. L�ve | Rhodiola integrifolia ssp. integrifolia | Crassulaceae
|
| TOME | Tolmiea menziesii (Pursh) Torr. & Gray | youth on age | Saxifragaceae
|
| TOLMI | Tolmiea Torr. & Gray | youth on age | Saxifragaceae
|
| TOBA | Tolpis barbata (L.) Gaertn. | European umbrella milkwort | Asteraceae
|
| TOUM | Tolpis umbellata Bertol. | Tolpis barbata | Asteraceae
|
| TOLPI | Tolpis Adans. | umbrella milkwort | Asteraceae
|
| TOBA2 | Tolumnia bahamensis (Nash ex Britt. & Millsp.) G.J. Braem | variegated orchid | Orchidaceae
|
| TOLE3 | Tolumnia leiboldii auct. non (Reichenb. f.) G.J. Braem | Tolumnia variegata | Orchidaceae
|
| TOPR3 | Tolumnia prionochila (Kraenzlin) G.J. Braem | tropical dancing-lady orchid | Orchidaceae
|
| TOVA | Tolumnia variegata (Sw.) G.J. Braem | harlequin dancing-lady orchid | Orchidaceae
|
| TOLUM | Tolumnia G.J. Braem | dancing-lady orchid | Orchidaceae
|
| TOAU | Tomanthera auriculata (Michx.) Raf. | Agalinis auriculata | Scrophulariaceae
|
| TODE | Tomanthera densiflora (Benth.) Pennell | Agalinis densiflora | Scrophulariaceae
|