Sedum anglicum
English Stonecrop
Senecio squalidus
Oxford Ragwort
Senecio viscosus
Sticky Groundsel
Senecio vulgaris
Groundsel
Sequoia sempervirens
Coastal Redwood
Sequoiadendron giganteum
Wellingtonia
Serratula tinctoria
Saw-wort
Setaria viridis
Green Bristle-grass
Sherardia arvensis
Field Madder
Sibthorpia europaea
Cornish Moneywort
Silaum silaus
Pepper-saxifrage
Silene dioica
Red Campion
Silene flos-cuculi
Ragged-Robin
Silene gallica
Small-flowered Catchfly
Silene latifolia
White Campion
Silene uniflora
Sea Campion
Smyrnium olusatrum
Alexanders
Solanum dulcamara
Bittersweet
Solanum nigrum
Black Nightshade
Solidago virgaurea
Goldenrod
Sonchus asper
Prickly Sow-thistle
Sorbus aria
Common Whitebeam
Sorbus aucuparia
Rowan
Sorbus minima
Least Whitebeam