Senecio viscosus
Sticky Groundsel
Senecio vulgaris
Groundsel
Serratula tinctoria
Saw-wort
Silaum silaus
Pepper-saxifrage
Silene gallica
Small-flowered Catchfly
Silene noctiflora
Night-flowering Catchfly
Silene viscaria
Sticky Catchfly
Silene vulgaris
Bladder Campion
Sinapis alba
White Mustard
Sinapis arvensis
Charlock
Sisymbrium officinale
Hedge Mustard
Sisyrinchium bermudiana
Blue-eyed-grass
Smyrnium olusatrum
Alexanders
Solanum aethiopicum
Ethiopian Eggplant
Solanum chenopodioides
Tall Nightshade
Solanum dulcamara
Bittersweet
Solanum erianthum
Velvet Nightshade
Solanum nigrum
Black Nightshade
Solanum nitidibaccatum
Green Nightshade
Solidago virgaurea
Goldenrod
Sonchus arvensis
Perennial Sow-thistle
Sorbus aria
Common Whitebeam
Sorbus aucuparia
Rowan
Sorbus cambrensis
Welsh Whitebeam