Senecio niveoaureus 
Senecio pinnatifolius 
Senecio serpens 
Senecio vernalis 
Shaggy Blazing Star 
Shaggy soldier 
Shepherd's needles 
Showy Goldenrod 
Showy Goldenrod 
Shrubby Everlasting 
Siam Weed 
Siebera nana 
Silver burr ragweed 
Silver Thistle 
Silver thistle 
Silver wormwood 
Silver-leaved yarrow 
silvercrown 
Silverpuffs 
Single-flower Knapweed 
Singlehead pussytoes 
Sky Blue Aster 
Slender Salsify 
Slender Sowthistle