Thistle spindle 
Thread-leaf fleabane 
Three-leaved Rattlesnakeroot 
Tolpis succulenta 
Tolpis umbellata 
Tragopogon buphthalmoides 
Tragopogon collinus 
Trailing African Daisy 
Trailing African daisy 
Trailing Daisy 
Trailing Treasureflower 
Tree everlasting 
Triangle-leaf Bursage 
Tripleurospermum auriculatum 
Tripleurospermum oreades 
Tuberous hawk's-beard 
Tuberous Hawkbit 
Tyrol Knapweed 
Upright Prairie Coneflower 
Velvet centaurea 
Velvet plant 
Velvet Turtleback 
Vipers grass 
Volutaria crupinoides