Wide-leaved bellflower 
Wig Knapweed 
Willowleaf Lettuce 
Winged Everlasting Daisy 
Wingstem 
Wolf's Bane 
Woodbridge poison 
Woodland Black-eyed Susan 
Woodland lettuce 
Woodland Madia 
Woodland ragwort 
Woodland Sunflower 
Woolly burdock 
Woolly Everlasting 
Woolly hawkweed 
Woolly pussytoes 
Woolly Thistle 
Wormwood 
Wrinkleleaf goldenrod 
Xeranthemum annuum 
Xeranthemum cylindraceum 
Yacón 
Yam daisy 
Yellow Coneflower