Click on a common name for a photo of the plant, or click on a letter for names beginning with that letter.
| Tearthumb, Arrowleaf |
Persicaria sagittata |
| Tearthumb, Triangle-leaf |
Persicaria arifolia |
| Teasel, Fuller's |
Dipsacus fullonum |
| Thistle, Bull |
Cirsium vulgare |
| Thistle, Canada |
Cirsium arvense |
| Thistle, Field |
Cirsium discolor |
| Thistle, Musk |
Carduus nutans |
| Thistle, Pasture |
Cirsium pumilum |
| Thistle, Swamp |
Cirsium muticum |
| Thistle, Yellow |
Cirsium horridulum var. horridulum |
| Thoroughwort, Dog-fennel |
Eupatorium capillifolium |
| Thoroughwort, Hyssop-leaf |
Eupatorium hyssopifolium |
| Thoroughwort, Late-flowering |
Eupatorium serotinum |
| Thoroughwort, Perfoliate |
Eupatorium perfoliatum |
| Thoroughwort, Ragged |
Eupatorium pilosum |
| Thoroughwort, Roundleaf |
Eupatorium rotundifolium var. rotundifolium |
| Three-seeded Mercury |
Acalypha rhomboidea |
| Tick-seed, Devil's |
Bidens frondosa |
| Tick-seed, Nodding |
Bidens cernua |
| Tick-seed, Smooth |
Bidens laevis |
| Tick-seed, Spanish-needle |
Bidens bipinnata |
| Tick-seed, Three-lobe |
Bidens comosa |
| Tick-trefoil, Bare-stemmed |
Hylodesmum nudiflorum |
| Tick-trefoil, Dillen's |
Desmodium glabellum |
| Tick-trefoil, Hairy Small-leaved |
Desmodium ciliare |
| Tick-trefoil, Panicled-leaf |
Desmodium paniculatum var. paniculatum |
| Tick-trefoil, Perplexed |
Desmodium perplexum |
| Tick-trefoil, Showy |
Desmodium canadense |
| Tickseed, Golden |
Coreopsis tinctoria var. tinctoria |
| Toadflax, Old-field |
Nuttallanthus canadensis |
| Toadflax, Umbellate Bastard |
Comandra umbellata subsp. umbellata |
| Toothwort, Cutleaf |
Cardamine concatenata |
| Toothwort, Slender |
Cardamine angustata |
| Tree, Groundsel |
Baccharis halimifolia |
| Tree-of-heaven |
Ailanthus altissima |
| Trefoil, Birds-foot |
Lotus corniculatus |
| Trillium, Great White |
Trillium grandiflorum |
| Trillium, Ill-scented |
Trillium erectum |
| Trillium, Nodding |
Trillium cernuum |
| Trillium, Red |
Trillium erectum |
| Trillium, Yellow |
Trillium luteum |
| Trout-lily, Yellow |
Erythronium americanum subsp. americanum |
| Trumpet-creeper |
Campsis radicans |
| Tuliptree |
Liriodendron tulipifera |
| Turtlehead, White |
Chelone glabra |
| Twayblade, Large |
Liparis liliifolia |
| Twayblade, Southern |
Neottia bifolia |