76 WILD MEDICINAL PLANTS OF THE UNITED STATES. 



Wood-Korrel, white. See OxiiUi^ aretoxeUa. 

 Wood-violet. See Viola pedata. 

 Worm-grass. See Spif/elia marilandica. 

 Wormseed. See Chenopodium anthelmirdicum. 

 Wormseed, American. See Chenopodium ambrosioides. 

 Wormwood. See Artemisia absinthium. 

 Wormwood, Roman. See Ambrosia artemisiaefolia. 



Xanthium spinosum L. Ragweed family ( Ambrosiaceae). 



Spiny clotbur; spiny burseed; thorny clotweed; thorny burweed. 



An annual weed, 1 to 3 feet high, naturalized from Europe or Asia; in waste 

 ground, Ontario to Florida, westward to Missouri and Texas. 



Part used. — -Leaves (nonofficial). 



Xanthorrliiza apiifolia L'Her. Crowfoot family (Ranunculaceae). 



Shrub yellowroot; southern yellowroot. 



Low, shrubby, indigenous perennial, 1 to 2 feet high, growing in woods and 

 along river Ijanks, southwestern New York to Florida, chiefly in the moun- 

 tains. 



Parts used. — Rhizome and roots (nonofficial). 

 Xanthoxylum. See Fagara rlara-herculis and Xantlioxylum americanum. 



Xanthoxylum americanum Mill. Rue family (Rutaceae). 



Sy)i<myra. — Xa utliox yluui fraxineum Willd. 



Xanthoxylum; northern prickly ash; toothache-tree. 



Indigenous shrub or small tree, maximum height about 25 feet; common in 

 woods and thickets and along river banks from Virginia, Missouri, and 

 Nebraska northward to Canada. 



Parts used. — Bark of this or of Fagara dava-herculis official under the name 

 "Xanthoxylum." Berries (nonofficial). 



Xanthoxylum dava-herculis L. Same as Fagara dava-liercidis. 



Xanthoxylum fraocineum Willd. Same as Xanthoxylum americanum. 



Yam, wild. See Dioseorea villosa. 



Yarrow. See Achiltea millefolium. 



Yellowroot. See Coptis trifolia, Hydrastis canadensis, and Jeffersonia di]»hy/la. 



Yellowroot, shrub. See Xanthorrhiza apiifolia. 



Yellowroot, southern. See Xanthorrhiza apiifolia. 



Yellowthorn. See Fagara dava-herculis. 



Ycllowwood. See Fagara dava-herculis. 



Yerba buena. See Micromeria chamissonis. 



Yerba reuma. See Frunkenia grandifolia. 



Yerba santa. See Eriodictyoii calif ornicum . 



Youthwort. See Drosera rotundifolia and Heradcutn lanatum. 



o 



