Sorbus minima
Least Whitebeam
Sorbus torminalis
Wild Service-tree
Sparganium erectum
Branched Bur-reed
Sparganium natans
Least Bur-reed
Spergula arvensis
Corn Spurrey
Spergularia marina
Lesser Sea-spurrey
Spergularia media
Greater Sea-spurrey
Spergularia rubra
Sand Spurrey
Spergularia rupicola
Rock Sea-spurrey
Sphagneticola trilobata
Bay Biscayne Creeping-oxeye
Spiranthes romanzoffiana
Irish Lady's-tresses
Spiranthes spiralis
Autumn Lady's-tresses
Splachnum ampullaceum
Cruet Collar-moss
Stachys arvensis
Field Woundwort
Stachys germanica
Downy Woundwort
Stachys palustris
Marsh Woundwort
Stachytarpheta jamaicensis
Blue Porterweed
Stapelia variegata
Stellaria alsine
Bog Stitchwort
Stellaria aquatica
Water Chickweed
Stellaria graminea
Lesser Stitchwort
Stellaria holostea
Greater Stitchwort
Stellaria neglecta
Greater Chickweed
Sternbergia lutea
Winter Daffodil