Sheep's Burr 
shinyleaf spiraea 
Shortleaf Fig 
Shrubby Cinquefoil 
Siberian Crabapple 
Silverweed cinquefoil 
Sitka mountain-ash 
Slender cinquefoil 
Slippery Elm 
Snowy Mespilus 
Sorbaria 
Sorbus domestica 
Sorbus glabrescens 
Sorbus umbellata 
Southern Dewberry 
Spade Leaf Fig 
Spiny Burnet 
Spiraea crenata 
Spring cinquefoil 
Steeplebush 
Sticky cinquefoil 
Stinging nettle 
Stone Bramble 
Strawberryleaf Cinquefoil