Search by Common Name
291 records
| Common Name | Other Names | Scientific Name | Family |
|---|---|---|---|
| sacred bamboo | heavenly bamboo, nanten | Nandina domestica | Berberidaceae |
| sacred lotus | Nelumbo nucifera | Nelumbonaceae | |
| sagittaire à feuilles de graminées | grass-leaf arrowhead, grassy arrowhead, sagittaire a feuilles de graminees, grass-leaved sagittaria | Sagittaria graminea | Alismataceae |
| salt heliotrope | quail plant, seaside heliotrope, cola de mico, cola de gama, seaside-heliotrope | Heliotropium curassavicum | Boraginaceae |
| salt sandspurry | salt-marsh sand-spurrey | Spergularia salina | Caryophyllaceae |
| saltmarsh bulrush | cosmopolitan bulrush | Bolboschoenus maritimus | Cyperaceae |
| salt-marsh camphor-weed | camphor pluchea, camphor weed, camphor-weed | Pluchea camphorata | Asteraceae |
| saltmarsh false foxglove | seaside gerardia, salt marsh gerardia | Agalinis maritima | Scrophulariaceae |
| saltmarsh fimbry | saltmarsh fimbristylis, marsh fimbry | Fimbristylis spadicea | Cyperaceae |
| saltmarsh loosestrife | wand lythrum, narrow-leaved loosestrife | Lythrum lineare | Lythraceae |
| saltmarsh mallow | virginia saltmarsh willow, virginia saltmarsh mallow, virginia fen-rose, seashore mallow, salt marsh-mallow | Kosteletzkya pentacarpos | Malvaceae |
| salt-marsh morning-glory | saltmarsh morningglory | Ipomoea sagittata | Convolvulaceae |
| saltmarsh umbrella-sedge | saltmarsh umbrellasedge, umbrella-grass | Fuirena breviseta | Cyperaceae |
| saltwater false willow | Baccharis angustifolia | Asteraceae | |
| saltwort | turtleweed, seaside saltwort | Batis maritima | Bataceae |
| sampson's snakeroot | Orbexilum pedunculatum | Fabaceae | |
| sand bittercress | smallflowered bittercress | Cardamine parviflora | Brassicaceae |
| sand live oak | Quercus geminata | Fagaceae | |
| sand rose gentian | sand rosegentian, sand rose-gentian | Sabatia arenicola | Gentianaceae |
| sand spikemoss | Selaginella arenicola | Selaginellaceae | |
| sand spike-rush | sand spikerush, palmer's spikerush | Eleocharis montevidensis | Cyperaceae |
| sandbar willow | sand-bar willow | Salix interior | Salicaceae |
| sand-barrens sundrops | threadleaf sundrop, threadleaf evening-primrose, threadleaf evening primrose, three leaved sundrops | Oenothera linifolia | Onagraceae |
| sanddune sandbur | Cenchrus tribuloides | Poaceae | |
| sandswamp whitetop | sand-swamp whitetop sedge, tall whitetop sedge, whitetop sedge, sand-swamp whitetop, tall whitetop, white top, colorful rush | Rhynchospora latifolia | Cyperaceae |
| sarsparilla vine | wild sarsaparilla, dwarf smilax, dwarf greenbriar | Smilax pumila | Smilacaceae |
| sarvis holly | swamp holly, sarvis-holly | Ilex amelanchier | Aquifoliaceae |
| sassafras | ague tree, cinnamon wood, mitten tree, saloop, smelling stick, white sassafras, gumbo file | Sassafras albidum | Lauraceae |
| savannah meadowbeauty | Rhexia alifanus | Melastomataceae | |
| savannah sneezeweed | Helenium vernale | Asteraceae | |
| saw greenbrier | zarzaparilla, catbrier, bullbrier, greenbrier | Smilax bona-nox | Smilacaceae |
| saw palmetto | Serenoa repens | Arecaceae | |
| sawtooth blackberry | prickly florida blackberry | Rubus argutus | Rosaceae |
| sawtooth oak | Quercus acutissima | Fagaceae | |
| sawtooth sunflower | saw-tooth sunflower | Helianthus grosse-serratus | Asteraceae |
| scalloped milkwort | Polygala crenata | Polygalaceae | |
| scaly blazing star | scaly gayfeather, scaly liatris | Liatris squarrosa | Asteraceae |
| scarlet beardtongue | scarlet penstemon, red penstemon, red beardtongue, cupleaf penstemon, cupleaf beardtongue | Penstemon murrayanus | Scrophulariaceae |
| scarlet firethorn | Pyracantha coccinea | Rosaceae | |
| scarlet rosemallow | crimson rosemallow, wild red mallow, texas star hibiscus | Hibiscus coccineus | Malvaceae |
| scarlet spiderling | red boerhavia, hogweed | Boerhavia coccinea | Nyctaginaceae |
| scarlett pimpernel | scarlet pimpernel, pimpernel, hierba del pajaro, poorman's weatherglass | Anagallis arvensis | Primulaceae |
| sea ox-eye | bushy seaside tansy, bushy seaoxeye, oxeye daisy, sea daisy, sea ox-eye | Borrichia frutescens | Asteraceae |
| seabeach evening primrose | spreading evening-primrose | Oenothera humifusa | Onagraceae |
| seacoast marsh elder | seacoast marshelder | Iva imbricata | Asteraceae |
| seaoats | Uniola paniculata | Poaceae | |
| seashore dropseed | coastal dropseed | Sporobolus virginicus | Poaceae |
| seashore paspalum | Paspalum vaginatum | Poaceae | |
| seaside brookweed | water-pimpernel, water pimpernel | Samolus valerandi | Primulaceae |
| seaside bulrush | seaside club-rush, sturdy bulrush, leafy three-square | Bolboschoenus robustus | Cyperaceae |
| seaside goldenrod | Solidago sempervirens | Asteraceae | |
| seaside primrose-willow | seaside ludwigia, harper's seedbox | Ludwigia maritima | Onagraceae |
| seedbox | bushy seedbox, square-pod water-primrose, rattle-box, seed-box | Ludwigia alternifolia | Onagraceae |
| sensitive brier | mimosa, littleleaf sensitive briar, sensitive brier, sensitive briar, little-leaf mimosa, catclaw sensitive briar, smooth-leaf sensitive briar, pink sensitive briar, shame vine | Mimosa microphylla | Fabaceae |
| sensitive fern | bead fern, sympathy fern | Onoclea sensibilis | Dryopteridaceae |
| sensitive partridge pea | sensitive plant, partridge pea, partridge-pea, sensitive patridge pea, sensitive pea | Chamaecrista nictitans | Fabaceae |
| sericea lespedeza | chinese lespedeza, chinese bush clover, sericea | Lespedeza cuneata | Fabaceae |
| sessileleaf bellwort | sessile-leaf bellwort, spreading bellwort, straw lily, wild oats, merrybells, sessile bellwort, small bellwort | Uvularia sessilifolia | Liliaceae |
| shade betony | mouse's-ear, mousesear | Stachys crenata | Lamiaceae |
| shade mudflower | shade mud-flower | Micranthemum umbrosum | Scrophulariaceae |
| shaggy hedgehyssop | hairy hedge-hyssop | Gratiola pilosa | Scrophulariaceae |
| shallow sedge | sallow sedge, lurid sedge | Carex lurida | Cyperaceae |
| sharpscale flatsedge | Cyperus oxylepis | Cyperaceae | |
| sharpscale sedge | Carex oxylepis | Cyperaceae | |
| sharpwing monkeyflower | sharpwing monkey-flower | Mimulus alatus | Scrophulariaceae |
| shepard's purse | shepherd's purse, shepherdspurse, paniquesillo | Capsella bursa-pastoris | Brassicaceae |
| shiny coneflower | texas coneflower | Rudbeckia texana | Asteraceae |
| shiny golden-rod | Solidago nitida | Asteraceae | |
| shore little bluestem | Schizachyrium scoparium var. littorale | Poaceae | |
| shoregrass | Monanthochloe littoralis | Poaceae | |
| shoreline seapurslane | cencilla, sea purslane | Sesuvium portulacastrum | Aizoaceae |
| shoreline sedge | blue ditch sedge | Carex hyalinolepis | Cyperaceae |
| shortbeak beaksedge | Rhynchospora nitens | Cyperaceae | |
| shortbristle horned beaksedge | horned rush | Rhynchospora corniculata | Cyperaceae |
| shortleaf lobelia | Lobelia brevifolia | Campanulaceae | |
| shortleaf pine | yellow pine, spruce pine, arkansas pine, shortleaf yellow pine, shortstraw pine, southern yellow pine | Pinus echinata | Pinaceae |
| shortleaf spikesedge | Kyllinga brevifolia | Cyperaceae | |
| short-point flatsedge | taperleaf flatsedge, taper-tip flat sedge, tapertip flatsedge | Cyperus acuminatus | Cyperaceae |
| showy evening-primrose | largeflower eveningprimrose, showy eveningprimrose, showy evening primrose | Oenothera grandis | Onagraceae |
| showy evening-primrose | showy evening primrose, showy eveningprimrose, pinkladies, pink evening primrose, mexican evening primrose, showy primrose, pink ladies, buttercups, pink buttercups, amapola del campo | Oenothera speciosa | Onagraceae |
| showy fanpetals | lindheimer's sida | Sida lindheimeri | Malvaceae |
| showy milkwort | Polygala grandiflora | Polygalaceae | |
| showy orchid | snowy orchid, frog spear | Gymnadeniopsis nivea | Orchidaceae |
| showy rattlebox | showy crotalaria | Crotalaria spectabilis | Fabaceae |
| shrubby st. johnswort | shrubby st. johns-wort | Hypericum prolificum | Clusiaceae |
| shumard's oak | shumard oak, shumard red oak, southern red oak, swamp red oak | Quercus shumardii | Fagaceae |
| shyleaf | american joint vetch, joint vetch, deer vetch | Aeschynomene americana | Fabaceae |
| sicklepod | arabette du canada, sicklepod rockcress | Arabis canadensis | Brassicaceae |
| sidebeak pencil-flower | endbeak pencilflower, sidebeak pencilflower, pencil flower | Stylosanthes biflora | Fabaceae |
| sideoats grama | Bouteloua curtipendula | Poaceae | |
| silkgrass | narrowleaf silkgrass, grass-leaved golden-aster, silk-grass | Pityopsis graminifolia | Asteraceae |
| silky camellia | virginia stewartia, round-fruited stewartia | Stewartia malacodendron | Theaceae |
| silky evolvulus | silver dwarf morningglory, silver dwarf morning-glory, white evolvulus | Evolvulus sericeus | Convolvulaceae |
| silky prairie clover | downy prairie-clover, hairy prairieclover | Dalea villosa | Fabaceae |
| silver beardgrass | silver bluestem | Bothriochloa laguroides | Poaceae |
| silver hairgrass | Aira caryophyllea | Poaceae | |
| silver maple | soft maple, white maple | Acer saccharinum | Aceraceae |
| silverhead | Blutaparon vermiculare | Amaranthaceae | |
| silverleaf nightshade | tomato weed, trompillo, white horsenettle, white nightshade, silver-leaf nightshade, white horse nettle, tomato weed, white horse-nettle | Solanum elaeagnifolium | Solanaceae |
| single-stem scurfpea | singlestem leather-root, simple scurfpea | Orbexilum simplex | Fabaceae |
| skyblue aster | sky blue american aster | Symphyotrichum oolentangiense | Asteraceae |
| slash pine | pitch pine, yellow slash pine | Pinus elliottii | Pinaceae |
| sleepy catchfly | catchfly, sleepy campion, sleepy silene | Silene antirrhina | Caryophyllaceae |
| sleepydick | star of bethlehem, pyrenees star of bethlehem | Ornithogalum umbellatum | Liliaceae |
| slender amaranth | Amaranthus viridis | Amaranthaceae | |
| slender beaksedge | Rhynchospora gracilenta | Cyperaceae | |
| slender blazingstar | sharp blazing star, sharp gayfeather, sharp liatris | Liatris acidota | Asteraceae |
| slender bluestem | slender little bluestem | Schizachyrium tenerum | Poaceae |
| slender false dragonhead | intermediate dragonhead, marsh obedient-plant, obedient-plant, spring obedient plant | Physostegia intermedia | Lamiaceae |
| slender fimbry | Fimbristylis autumnalis | Cyperaceae | |
| slender meadow foxtail | blackgrass, slender foxtail | Alopecurus myosuroides | Poaceae |
| slender mountain-mint | narrowleaf mountainmint, slender mountainmint, slender mountain mint, common horsemint | Pycnanthemum tenuifolium | Lamiaceae |
| slender rosinweed | Silphium radula var. gracile | Asteraceae | |
| slender scratchdaisy | scratch daisy, granite daisy | Croptilon divaricatum | Asteraceae |
| slender threeseed mercury | slender copperleaf | Acalypha gracilens | Euphorbiaceae |
| slender wedgescale | slender wedgegrass | Sphenopholis intermedia | Poaceae |
| slender woodoats | spike uniola, slender chasmanthium | Chasmanthium laxum | Poaceae |
| slender yellow woodsorrel | yellow wood sorrel, gray-green wood sorrel, southern yellow wood-sorrel | Oxalis dillenii | Oxalidaceae |
| slenderfruit nutrush | slender nut-rush | Scleria georgiana | Cyperaceae |
| slenderleaf false foxglove | slender-leaf false foxglove | Agalinis tenuifolia | Scrophulariaceae |
| slenderleaf fleabane | Erigeron tenuis | Asteraceae | |
| slickseed fuzzybean | slick-seed bean, piper | Strophostyles leiosperma | Fabaceae |
| slim spikerush | Eleocharis elongata | Cyperaceae | |
| slimpod rush | slimpod-rush | Juncus diffusissimus | Juncaceae |
| slimspike prairie clover | Dalea phleoides | Fabaceae | |
| slimspike threeawn | Aristida longespica var. geniculata | Poaceae | |
| small ballmoss | ball moss, gallitos | Tillandsia recurvata | Bromeliaceae |
| small beggarticks | swamp beggar-ticks, discoid beggarticks, swamp beggarticks | Bidens discoidea | Asteraceae |
| small butterwort | bog violet, dwarf butterwort | Pinguicula pumila | Lentibulariaceae |
| small green wood orchid | green woodland orchid, small woodland orchid | Gymnadeniopsis clavellata | Orchidaceae |
| small palafoxia | small palafox | Palafoxia callosa | Asteraceae |
| small skullcap | Scutellaria parvula | Lamiaceae | |
| small spreading pogonia | spreading pogonia, rosebud orchid | Cleistesiopsis bifri | Orchidaceae |
| smallflower baby blue eyes | Nemophila aphylla | Hydrophyllaceae | |
| smallflower desert-chicory | texas dandelion, false dandelion | Pyrrhopappus pauciflorus | Asteraceae |
| smallflower fumewort | southern corydalis, golden corydalis, slender fumewort, slender corydalis | Corydalis micrantha | Fumariaceae |
| smallflower groundcherry | Physalis cinerascens | Solanaceae | |
| smallflower pawpaw | small flower pawpaw, small-flower pawpaw, dwarf pawpaw | Asimina parviflora | Annonaceae |
| small-flower thoroughwort | smallflower thoroughwort, smallflower eupatorium | Eupatorium semiserratum | Asteraceae |
| smallfruit beggarticks | coastal plain tickseed sunflower | Bidens mitis | Asteraceae |
| smallfruit primrose-willow | smallfruit primrosewillow | Ludwigia microcarpa | Onagraceae |
| small-fruit spikerush | smallfruit spikerush | Eleocharis microcarpa | Cyperaceae |
| smallhead cat's ear | Hypochaeris microcephala | Asteraceae | |
| smallhead doll's daisy | doll's daisy | Boltonia diffusa | Asteraceae |
| small's blacksnakeroot | Sanicula smallii | Apiaceae | |
| small's noseburn | Tragia smallii | Euphorbiaceae | |
| small-spike false nettle | smallspike false nettle, bog hemp, false nettle, button hemp | Boehmeria cylindrica | Urticaceae |
| smooth beggartick | smooth beggarticks, bur marigold, smooth bidens, smooth bur marigold, larger bur marigold, showy bur marigold | Bidens laevis | Asteraceae |
| smooth brome | awnless brome | Bromus inermis | Poaceae |
| smooth cordgrass | saltmarsh cordgrass, salt cordgrass, atlantic cordgrass | Spartina alterniflora | Poaceae |
| smooth crabgrass | small crabgrass, smooth crab grass | Digitaria ischaemum | Poaceae |
| smooth elephantsfoot | naked elephantsfoot, naked elephantfoot | Elephantopus nudatus | Asteraceae |
| smooth false buttonweed | buttonplant, smooth buttonweed, buttonweed | Spermacoce glabra | Rubiaceae |
| smooth hedgenettle | slender betony, smooth hedge-nette, hedge nettle, thinleaf betony, slenderleaf betony | Stachys tenuifolia | Lamiaceae |
| smooth jewelflower | Streptanthus hyacinthoides | Brassicaceae | |
| smooth oxeye | Heliopsis helianthoides | Asteraceae | |
| smooth phacelia | Phacelia glabra | Hydrophyllaceae | |
| smooth small-leaf ticktrefoil | maryland ticktrefoil, maryland tickclover | Desmodium marilandicum | Fabaceae |
| smooth solomon's seal | great solomon's seal, sealwort | Polygonatum biflorum | Liliaceae |
| smooth sumac | common sumac, scarlet sumac | Rhus glabra | Anacardiaceae |
| snakemouth orchid | Pogonia ophioglossoides var. brachypogon | Orchidaceae | |
| snakemouth orchid | snake-mouth orchid, beard flower, rose pogonia, snake-mouth | Pogonia ophioglossoides | Orchidaceae |
| snow on the mountain | Euphorbia marginata | Euphorbiaceae | |
| snow on the prairie | Euphorbia bicolor | Euphorbiaceae | |
| soft goldenaster | soft golden-aster | Bradburia pilosa | Asteraceae |
| soft greeneyes | Berlandiera pumila | Asteraceae | |
| soft thistle | carolina thistle, spring thistle, tall thistle | Cirsium carolinianum | Asteraceae |
| soft-hair marbleseed | Onosmodium bejariense | Boraginaceae | |
| softseed wild petunia | britton's wild petunia. mexican petunia | Ruellia simplex | Acanthaceae |
| soft-stem bulrush | great bulrush, softstem bulrush, soft-strem club-rush | Schoenoplectus tabernaemontani | Cyperaceae |
| sorrelvine | grape ivy, possum grape, cow-itch vine, arizona grape ivy, marine-ivy, possum-grape, treebine, hierba del buey, | Cissus trifoliata | Vitaceae |
| sourwood | sorrel tree | Oxydendrum arboreum | Ericaceae |
| south american mock vervain | Glandularia pulchella | Verbenaceae | |
| south american skullcap | Scutellaria racemosa | Lamiaceae | |
| south american vervain | pretty verbena, purpletop vervain | Verbena bonariensis | Verbenaceae |
| southern adderstongue | southern adder's-tongue, herbe sans couture, adder's-tongue, adder's-tongue fern | Ophioglossum vulgatum | Ophioglossaceae |
| southern amaranth | southern water-hemp | Amaranthus australis | Amaranthaceae |
| southern annual saltmarsh aster | lawn american-aster, white wood aster, saltmarsh aster | Symphyotrichum subulatum var. ligulatum | Asteraceae |
| southern arrowwood | arrowwood, arrow-wood viburnum | Viburnum dentatum | Caprifoliaceae |
| southern bayberry | evergreen bayberry, swamp bayberry, swamp candleberry, baygall wax myrtle | Morella caroliniensis | Myricaceae |
| southern bayberry | waxmyrtle, wax myrtle, candleberry | Morella cerifera | Myricaceae |
| southern catalpa | cigar tree, indian bean | Catalpa bignonioides | Bignoniaceae |
| southern cattail | Typha domingensis | Typhaceae | |
| southern crab apple | southern crabapple, wild crabapple, crab-apple | Malus angustifolia | Rosaceae |
| southern crabgrass | southern crab grass, fingergrass, henry's crabgrass, kukaepua'a, saulangi, smooth crabgrass, tropical crabgrass | Digitaria ciliaris | Poaceae |
| southern cutgrass | Leersia hexandra | Poaceae | |
| southern dawnflower | white stylisma | Stylisma humistrata | Convolvulaceae |
| southern dewberry | dewberry, zarzamora | Rubus trivialis | Rosaceae |
| southern jointweed | Polygonella americana | Polygonaceae | |
| southern long sedge | Carex lonchocarpa | Cyperaceae | |
| southern magnolia | laurier tulipier, bull-bay, bull bay, evergreen magnolia | Magnolia grandiflora | Magnoliaceae |
| southern red oak | spanish oak | Quercus falcata | Fagaceae |
| southern shield fern | kunth's maiden fern, wood fern, river fern, southern shield fern, normal shield fern | Thelypteris kunthii | Thelypteridaceae |
| southern spicebush | pondberry | Lindera melissifolia | Lauraceae |
| southern sugar maple | hammock maple, florida maple, caddo maple, rock maple | Acer barbatum | Aceraceae |
| southern twayblade | Neottia bifolia | Orchidaceae | |
| southern umbrella-sedge | southern umbrellasedge, umbrella-grass | Fuirena scirpoidea | Cyperaceae |
| southern watergrass | luziola, watergrass | Luziola fluitans | Poaceae |
| southern waternymph | southern naiad, naïade de la guadeloupe, guadalupe waternymph, common waternymph, southern waternymph, common water-nymph | Najas guadalupensis | Najadaceae |
| southern waxy sedge | clustered sedge | Carex glaucescens | Cyperaceae |
| southern woodfern | florida shieldfern | Dryopteris ludoviciana | Dryopteridaceae |
| soxman's milkvetch | Astragalus soxmaniorum | Fabaceae | |
| spanish moss | spanish-moss, heno, pastle | Tillandsia usneoides | Bromeliaceae |
| spanish needles | spanish-needles | Bidens bipinnata | Asteraceae |
| spearmint | bush mint | Mentha spicata | Lamiaceae |
| spiked crested coralroot | crested coral-root | Hexalectris spicata | Orchidaceae |
| spiny aster | spiny chloracantha, devilweed aster, mexican devilweed | Chloracantha spinosa | Asteraceae |
| spiny sowthistle | prickly sowthistle, spiny-leaved sowthistle, prickly sowthistle, spiny-leaf sow-thistle, perennial sowthistle, achicoria dulce | Sonchus asper | Asteraceae |
| spiny-fruit buttercup | spinyfruit buttercup | Ranunculus muricatus | Ranunculaceae |
| splitbeard bluestem | paintbrush bluestem | Andropogon ternarius | Poaceae |
| spoonleaf sundew | Drosera intermedia | Droseraceae | |
| spotted bee-balm | spotted beebalm, horsemint, spotted horsemint, dotted beebalm, horse mint, horse-mint | Monarda punctata | Lamiaceae |
| spotted geranium | wild geranium, cranesbill, wild cranesbill | Geranium maculatum | Geraniaceae |
| spotted ladysthumb | Persicaria maculosa | Polygonaceae | |
| spotted medic | spotted medick, southern burr clover, spotted burrclover, spotted burr-clover | Medicago arabica | Fabaceae |
| spotted sandmat | large spurge, spotted spurge, milk purslane, prostrate spurge | Euphorbia maculata | Euphorbiaceae |
| spotted st. johnswort | spotted st. johns-wort | Hypericum punctatum | Clusiaceae |
| spotted water hemlock | water hemlock, common waterhemlock, poison parsnip, spotted cowbane, spotted parsley, spotted water-hemlock, spotted waterhemlock, beaver poison, beaver-poison | Cicuta maculata | Apiaceae |
| spreading broomsedge | spreading sandmat | Euphorbia humistrata | Euphorbiaceae |
| spreading hedgeparsley | Torilis arvensis | Apiaceae | |
| spreading pygmyleaf | Loeflingia squarrosa | Caryophyllaceae | |
| spring coralroot orchid | spring coralroot, early southern coral-root, wister's coral-root, yellow coral-root, arousing coral-root | Corallorhiza wisteriana | Orchidaceae |
| spring forget-me-not | Myosotis verna | Boraginaceae | |
| spring ladies'-tresses | spring lady's tresses, upland ladiestresses, twisted lady's tresses, spring ladies' tresses | Spiranthes vernalis | Orchidaceae |
| spring pygmycudweed | Evax verna | Asteraceae | |
| spring spider-lily | Hymenocallis liriosme | Liliaceae | |
| spruce pine | bottom white pine, cedar pine, walter pine, walter's pine | Pinus glabra | Pinaceae |
| spurred butterfly pea | butterflypea | Centrosema virginianum | Fabaceae |
| squareflower | Paronychia erecta | Caryophyllaceae | |
| square-stem spike-rush | squarestem spikesedge, squarestem spikerush | Eleocharis quadrangulata | Cyperaceae |
| squarrose sedge | narrowleaf cattail sedge | Carex squarrosa | Cyperaceae |
| st. andrew's cross | Hypericum hypericoides | Clusiaceae | |
| st. augustine grass | st. augustinegrass | Stenotaphrum secundatum | Poaceae |
| st. peterswort | atlantic st. peterswort, atlantic st. peter's-wort | Hypericum crux-andreae | Clusiaceae |
| stalked wild petunia | Ruellia pedunculata | Acanthaceae | |
| stalkless yellowcress | Rorippa sessiliflora | Brassicaceae | |
| standing-cypress | texas plume, red texas star, red gilia | Ipomopsis rubra | Polemoniaceae |
| star tickseed | hairy coreopsis | Coreopsis pubescens | Asteraceae |
| starch grape hyacinth | Muscari neglectum | Liliaceae | |
| starry rosinweed | Silphium asteriscus | Asteraceae | |
| stemless evening primrose | Oenothera triloba | Onagraceae | |
| sticky chickweed | Cerastium glomeratum | Caryophyllaceae | |
| sticky waxweed | Cuphea glutinosa | Lythraceae | |
| stiff bluestar | marsh bluestar | Amsonia rigida | Apocynaceae |
| stiff cowbane | cowbane, water-dropwort | Oxypolis rigidior | Apiaceae |
| stiff dogwood | swamp dogwood, gray dogwood | Cornus foemina | Cornaceae |
| stiff goldenrod | hard-leaf goldenrod, rigid goldenrod | Solidago rigida | Asteraceae |
| stiff greenthread | greenthread | Thelesperma filifolium | Asteraceae |
| stiff marsh bedstraw | dye bedstraw | Galium tinctorium | Rubiaceae |
| stiff tickseed | stiff coreopsis, finger coreopsis | Coreopsis palmata | Asteraceae |
| stiff yellow flax | common yellow flax, | Linum medium | Linaceae |
| stinking camphorweed | stinking fleabane | Pluchea foetida | Asteraceae |
| stokes' aster | Stokesia laevis | Asteraceae | |
| stout rush | Juncus nodatus | Juncaceae | |
| straggler daisy | horseherb, hierba del caballo, lawnflower, carpet daisy | Calyptocarpus vialis | Asteraceae |
| strawcolored flatsedge | strawcolored nutgrass, strawcolor flatsedge, strawcolor nutgrass, strawcolored flatsedge | Cyperus strigosus | Cyperaceae |
| stream bogmoss | Mayaca fluviatilis | Mayacaceae | |
| suckling clover | hop clover, smallhop clover, shamrock, small hop clover, small hop-clover, little hop-clover | Trifolium dubium | Fabaceae |
| sugarberry | sugar hackberry, hackberry, texas sugarberry, palo blanco | Celtis laevigata | Ulmaceae |
| sugarcane | Saccharum officinarum | Poaceae | |
| sugarcane plumegrass | giant plume grass | Saccharum giganteum | Poaceae |
| sulphur cinquefoil | Potentilla recta | Rosaceae | |
| sulphur cosmos | Cosmos sulphureus | Asteraceae | |
| summer grape | pigeon grape | Vitis aestivalis | Vitaceae |
| summer snowflake | snowflake | Leucojum aestivum | Liliaceae |
| sunbright | dwarf flameflower, prairie flameflower | Phemeranthus parviflorus | Portulacaceae |
| swamp azalea | clammy azalea, texas azalea, swamp honeysuckle, cory azalea, hammock sweet azalea, swamp-azalea | Rhododendron viscosum | Ericaceae |
| swamp bay | swampbay, swamp-bay | Persea palustris | Lauraceae |
| swamp chestnut oak | basket oak, cow oak | Quercus michauxii | Fagaceae |
| swamp cottonwood | swamp poplar, black cottonwood, downy poplar | Populus heterophylla | Salicaceae |
| swamp dock | water dock | Rumex verticillatus | Polygonaceae |
| swamp hornpod | small-leaved mitrewort | Mitreola sessilifolia | Loganiaceae |
| swamp leather flower. curly clematis | blue-jasmine, curlflower, curly virgin's bower, marsh clematis | Clematis crispa | Ranunculaceae |
| swamp milkweed | rose milkweed | Asclepias incarnata | Asclepiadaceae |
| swamp milkwort | Polygala leptocaulis | Polygalaceae | |
| swamp sawgrass | Cladium mariscus | Cyperaceae | |
| swamp smartweed | mild water pepper, mild waterpepper, false waterpepper | Persicaria hydropiperoides | Polygonaceae |
| swamp sunflower | swamp sneezeweed, narrowleaf sunflower, narrow-leaved sunflower | Helianthus angustifolius | Asteraceae |
| swamp thistle | swamp-thistle | Cirsium muticum | Asteraceae |
| swamp titi | swamp cyrilla, leatherwood, palo colorado, black titi | Cyrilla racemiflora | Cyrillaceae |
| swamp tupelo | swamp blackgum | Nyssa biflora | Cornaceae |
| swamp verbena | blue verbena, blue vervain, simpler's joy | Verbena hastata | Verbenaceae |
| sweet acacia | huisache, texas huisache, klu bush, aroma, ellington's curse, kandaroma, klu, popinac, mealy wattle | Acacia farnesiana | Fabaceae |
| sweet autumn virginsbower | leatherleaf clemat, yam-leaved clematis | Clematis terniflora | Ranunculaceae |
| sweet basil | Ocimum basilicum | Lamiaceae | |
| sweet coneflower | sweet black-eyed susan | Rudbeckia subtomentosa | Asteraceae |
| sweetbay | sweet bay, laurier doux, swamp-bay | Magnolia virginiana | Magnoliaceae |
| sweet-gum | american sweetgum sweetgum | Liquidambar styraciflua | Hamamelidaceae |
| sweetscent | marsh fleabane, saltmarsh fleabane | Pluchea odorata | Asteraceae |
| sweetscented joe pye weed | purple-node joe-pye weed | Eutrochium purpureum | Asteraceae |
| swollen bladderwort | floating bladderwort, inflated bladderwort | Utricularia inflata | Lentibulariaceae |