| Sidalcea malviflora |
Sidalcea; Greek Mallow |
| Silene dioica |
Red Campion |
| Silene latifolia |
Sea Campion; White Campion |
| Silene uniflora |
Bladder Campion |
| Silene vulgaris |
Bladder Campion |
| Silybum marianum |
St. Mary's Thistle; Milk Thistle |
| Sinapis alba |
White Mustard |
| Sisymbrium officinale |
Hedgemustard; Hedge Mustard |
| Sisyrinchium californicum |
Californian Yellow-Maiden; Yellow-Eyed Grass |
| Solanum tuberosum |
Potato |
| Sonchus asper |
Prickly Sow-Thistle; Spiny Sow-Thistle |
| Sonchus asper asper |
Spiny Sow-Thistle; Prickly Sow-Thistle |
| Sonchus oleraceus |
Smooth Saw-Thistle; Smooth Sow-Thistle |
| Sorbus aucuparia |
Rowan |
| Spergula arvensis |
Corn Spurrey |
| Stellaria alsine |
Bog Chickweed; Bog Stitchwort |
| Stellaria media |
Common Chickweed; Chickweed |
| Stipa neaei |
|
| Suillus luteus |
|
| Suillus punctatipes |
|
| Sus scrofa |
Pig; Wild Boar; Pig |
| Sylvilagus |
Cottontails; North American Cotton-Tail Rabbit |
| Tanacetum parthenium |
Aureum; Feverfew; Gold Feverfew |
| Tanacetum vulgare |
Tansy |
| Taraxacum officinale |
Common Dandelion; Dandelion |
| Taurocerastes patagonicus |
|
| Thinopyrum junceum |
Sand Couch |
| Torreyostellaria jamesiana |
Lesser Stitchwort |
| Trametes versicolor |
|
| Tremella mesenterica |
|
