Safflower
Sage, Common
Sage, Lyreleaf
Sage, Pineapple
Sagebrush, White
Sagewort, Cudweed
Sagewort, Gray
Sagewort, Sweet
Sago Pondweed
Salad, European Corn
Salad, Northern Corn
Sallow Sedge
Salt, Pepper and
Sandbar Willow
Sandmat, Prostrate
Sandmat, Spotted
Sandmat, Spreading
Sandvine
Sandwort, Thyme-Leaved
Sassafras
Saucer Magnolia
Savannah False Pimpernel
Sawtooth Oak
Sawtooth Sunflower
Saxifrage, Early
Saxifrage, Virginia
Scarlet Beebalm
Scarlet Oak
Scarlet Pimpernel
Scotch Pine
Scouring Rush
Scouringrush Horsetail
Scrub Pine
Scurfpea, Lanceleaf
Sedge, Bicknell's
Sedge, Bristly
Sedge, Broad Looseflower
Sedge, Brown Fox
Sedge, Bur-Reed
Sedge, Carey's
Sedge, Common Wood
Sedge, Common Woodland
Sedge, Crested
Sedge, Fibrousroot
Sedge, Frank's
Sedge, Fringed
Sedge, Golden
Sedge, Gray's
Sedge, Hairy Wood
Sedge, Hairy-Leaved
Sedge, James'
Sedge, Lake
Sedge, Limestone Meadow
Sedge, Lurid
Sedge, Nodding
Sedge, Oval-Headed
Sedge, Palm
Sedge, Pennsylvania
Sedge, Plantainleaf
Sedge, Pointed Broom
Sedge, Prairie
Sedge, Prickly
Sedge, Reflexed
Sedge, Rosy
Sedge, Sallow
Sedge, Seersucker
Sedge, Short's
Sedge, Soft Fox
Sedge, Squarrose
Sedge, Swan's
Sedge, Tussock
Sedge, White Bear
Sedge, Wood Gray
Seedbox, Bushy
Seedbox, Marsh
Seersucker Sedge
Self-Heal
Selfheal, Common
Senna, Northern Wild
Senna, Southern Wild
Sensitive Fern
Serviceberry, Common
Serviceberry, Downy
Sessile Blazing Star
Sessile Trillium
Shadbush, Apple
Shagbark Hickory
Sharp-lobed Hepatica
Sharpwing Monkeyflower
Shasta Daisy
Shellbark Hickory
Shepherd's Purse
Shingle Oak
Shining Bedstraw
Shining Sumac
Shooting Star
Short Ragweed
Short's Aster
Short's Sedge
Shorthusk, Bearded
Showy Goldenrod
Showy Tick Trefoil
Shrubby St. John's Wort
Shumard Red Oak
Siberian Elm
Siberian Iris
Siberian Squill
Sicilian Honey Garlic
Sida, Prickly
Sideoats Grama
Siebold Viburnum
Silky Dogwood
Silky Wild Rye
Silver Bells
Silver Maple
Silvergrass, Chinese
Silvery Glade Fern
Skullcap, Downy
Skullcap, Forest
Skullcap, Heartleaf
Skullcap, Mad-Dog
Skunk Cabbage
Slender Mountainmint
Slender Muhly
Slender Pondweed
Slim Amaranth
Slimflower Muhly
Slipper, Yellow Lady's
Slippery Elm
Small Carpetgrass
Small White Aster
Small White Morning Glory
Small-Flowered Agrimony
Small-Flowered Crowfoot
Small-Flowered Leafcup
Smartweed
Smartweed, Dotted
Smartweed, Long-Bristled
Smartweed, Pale
Smartweed, Swamp
Smartweed, Water
Smooth Beardtongue
Smooth Blue Aster
Smooth Brome
Smooth Crabgrass
Smooth Forked Nailwort
Smooth Ground Cherry
Smooth Hedgenettle
Smooth Hydrangea
Smooth Milkweed
Smooth Rock Cress
Smooth Solomon's Seal
Smooth Sumac
Smooth Wild Petunia
Smooth Yellow Violet
Smoother Sweet Cicely
Snakeroot, Beaked
Snakeroot, Black
Snakeroot, Canadian Black
Snakeroot, Clustered Black
Snakeroot, Large-Fruited Black
Snakeroot, Virginia
Snakeroot, White
Snapdragon
Snapdragon, Dwarf
Sneezeweed, Common
Snow Trillium
Snowberry, Red
Snowdrop, Common
Snowdrop, Giant
Snowflake, Spring
Snowflake, Summer
Soapwort
Soft Fox Sedge
Soft Maple
Soft Rush
Soft-Stemmed Bulrush
Softstem Bulrush
Soldier, Gallant
Sorghum
Sorrel, Violet Wood
Sorrel, Yellow Wood
Sour Gum
Southern Adder's-Tongue
Southern Agrimony
Southern Blackhaw
Southern Fragile Fern
Southern Water Plantain
Southern Wild Senna
Sowthistle, Field
Sowthistle, Perennial
Sowthistle, Prickly
Sowthistle, Spiny
Spanish Bluebell
Spanish Needles
Spearmint
Speedwell, Common
Speedwell, Corn
Speedwell, Germander
Speedwell, Ivy-Leaved
Speedwell, Persian
Speedwell, Pink Ivy-Leaved
Speedwell, Purslane
Speedwell, Thyme-Leaved
Spicebush
Spider Flower
Spiderwort, Ohio
Spiderwort, Virginia
Spiderwort, Zigzag
Spikemoss, Meadow
Spikenard, American
Spikerush, Creeping
Spikerush, Ovate
Spikesedge, Pasture
Spindle, European
Spinulose Wood Fern
Spiny Sowthistle
Spiraea, Japanese
Spirea, Bridalwreath
Spirea, Van Houtte
Spleenwort, Ebony
Spotted Beebalm
Spotted Horse Mint
Spotted Jewelweed
Spotted Joe-Pye Weed
Spotted Knapweed
Spotted Sandmat
Spotted Spurge
Spotted St. John's Wort
Spotted Water Hemlock
Spreading Sandmat
Spring Avens
Spring Beauty
Spring Coralroot
Spring Cress
Spring Crocus
Spring Forget-Me-Not
Spring Snowflake
Spring Sternbergia
Springbeauty, Virginia
Spruce, Norway
Spruce, White
Spurge, Allegheny Mountain
Spurge, Chameleon
Spurge, Cypress
Spurge, David's
Spurge, Nodding
Spurge, Prostrate
Spurge, Spotted
Spurge, Toothed
Square, Carpenter's
Square-Pod Water-Primrose
Squarrose Sedge
Squawroot
Squill
Squill, Siberian
Squill, Striped
Squirrel Corn
Ssmooth Amaranth
St. Anthony's Turnip
Stag's Garlic
Staghorn Sumac
Star Chickweed
Star Magnolia
Star Sedge, Eastern
Star, Shooting
Star-of-Bethlehem
Stargrass, Yellow
Starry Campion
Starry Magnolia
Starwort, Terrestrial
Steeplebush
Sternbergia, Spring
Stickseed
Stickseed, Virginia
Sticktight
Stiff Goldenrod
Stiff Tickseed
Stiltgrass, Japanese
Stinging Nettle
Stonecrop, Ditch
Stonecrop, Gold Moss
Stonecrop, Stringy
Stonecrop, Wild
Straw Sedge, Greater
Strawberry, Indian
Strawberry, Mock
Strawcolored Fatsedge
Strawstem Beggar-Ticks
Stringy Stonecrop
Striped Cream Violet
Striped Squill
Sugar Maple
Sullivant's Milkweed
Sulphur Cinquefoil
Sumac, Fragrant
Sumac, Shining
Sumac, Smooth
Sumac, Staghorn
Sumac, Winged
Summer Grape
Summer Phlox
Summer Snowflake
Summer Wine
Summer Wine Ninebark
Summersweet clethra
Sundrops, Yellow
Sunflower, Ashy
Sunflower, Common
Sunflower, False
Sunflower, Forest
Sunflower, Giant
Sunflower, Long-Bracted Tickseed
Sunflower, Mexican
Sunflower, Ozark Tickseed
Sunflower, Sawtooth
Sunflower, Tall
Sunflower, Ten-Petal
Sunflower, Thin-Leaved
Sunflower, Tickseed
Sunflower, Woodland
Sunset, Outback
Surprise Lily
Susan, Black-Eyed
Susan, Brown-Eyed
Susan, Sweet Black-Eyed
Swamp Buttercup
Swamp Dodder
Swamp Milkweed
Swamp Rose Mallow
Swamp Smartweed
Swamp Verbena
Swamp White Oak
Swan's Sedge
Sweet Alyssum
Sweet Autumn Clematis
Sweet Autumn Virginsbower
Sweet Black-Eyed Susan
Sweet Goldenrod
Sweet Joe-Pye Weed
Sweet Mock Orange
Sweet Pepperbush
Sweet Pignut Hickory
Sweet Sagewort
Sweet Vernal Grass
Sweet-Scented Bedstraw
Sweet-Scented Water-Lily
Sweet-William
Sweet-amber
Sweetbay
Sweetbay Magnolia
Sweetflag
Sweetgum
Sweetleaf
Sweetpepperbush, Coastal
Sweetshrub, Eastern
Sweetspire, Virginia
Switchgrass
Swordfern, Fishtail
Sycamore
Sycamore, American
Synandra