Solidago canadensis
Canadian Goldenrod
Solidago gigantea
Early Goldenrod
Solidago virgaurea
Goldenrod
Sonchus arvensis
Perennial Sow-thistle
Sonchus asper
Prickly Sow-thistle
Sonchus oleraceus
Smooth Sow-thistle
Sonneratia caseolaris
Mangrove Apple
Sorbus aria
Common Whitebeam
Sorbus aucuparia
Rowan
Sorbus cambrensis
Welsh Whitebeam
Sorbus leptophylla
Thin-leaved Whitebeam
Sorbus leyana
Ley's Whitebeam
Sorbus minima
Least Whitebeam
Sorbus porrigentiformis
Grey-leaved Whitebeam
Sorbus rupicola
Rock Whitebeam
Sorbus stenophylla
Llanthony Whitebeam
Sorbus torminalis
Wild Service-tree
Sorbus x motleyi
Sparmannia sp.
African Hemp
Spathodea campanulata
African Tulip Tree
Spergula arvensis
Corn Spurrey
Spergularia marina
Lesser Sea-spurrey
Spergularia media
Greater Sea-spurrey
Spergularia rubra
Sand Spurrey
Spergularia rupicola
Rock Sea-spurrey
Spermacoce exilis
False Buttonweed
Spermacoce hispida
Shaggy Buttonweed
Spermacoce remota
Sphagneticola trilobata
Bay Biscayne Creeping-oxeye
Spigelia anthelmia
West Indian Pinkroot
Spiraea canescens
Himalayan Spiraea
Spiraea x rosalba
Intermediate Bridewort
Stachys alpina
Limestone Woundwort
Stachys arvensis
Field Woundwort
Stachys byzantina
Lamb's-ear
Stachys germanica
Downy Woundwort
Stachys palustris
Marsh Woundwort
Stachys sylvatica
Hedge Woundwort
Stachytarpheta jamaicensis
Blue Porterweed
Stapelia variegata
Staphylea pinnata
Bladdernut
Stellaria alsine
Bog Stitchwort
Stellaria aquatica
Water Chickweed
Stellaria graminea
Lesser Stitchwort
Stellaria holostea
Greater Stitchwort
Stellaria media
Common Chickweed
Stellaria neglecta
Greater Chickweed
Stellaria palustris
Marsh Stitchwort
Streptocarpus saxorum
False African Violet
Strobilanthes alternata
Red-ivy
Strobilanthes reptans
Waffle Plant
Stylosanthes guianensis
Stylo
Suaeda maritima
Annual Sea-blite
Succisa pratensis
Devil's-bit Scabious
Swietenia macrophylla
Mahogany
Swietenia macrphylla
Honduran Mahogany
Symphoricarpos albus
Snowberry
Symphyotrichum lanceolatum
Narrow-leaved Michaelmas-daisy
Symphytum asperum
Rough Comfrey
Symphytum officinale
Common Comfrey
Symphytum orientale
White Comfrey
Symphytum tuberosum
Tuberous Comfrey
Symphytum x hidcotense
Hidcote Comfrey
Symphytum x uplandicum
Russian Comfrey
Synedrella nodiflora
Nodeweed
Syzygium samarangense
Wax Apple
Tabernaemontana alternifolia
East Indian Rosebay
Tabernaemontana divaricata
Carnation of India
Tacinga inamoena
Quipá
Tagetes lucida
Mexican Tarragon