58 WILD MEDICINAL PLANTS OF THE UNITED STATES. 



Rattlesnake-master. See Eryngium yucci folium, Lucinaria )<cariosa, L. spicata, and 



L. squarrosa. 

 Rattlesnake-plantain, downy. See Feramium pubescens. 

 Rattlesnake-plantain, lesser. See Peramium repens. 

 Rattlesnake-root. See Nabalus albus and N. serpentarius. 

 Rattlesnake-violet. See Erythronluvi americanum. 



Rattlesnake-weed. See Eryngium yuccifolium, Hieracium vpnomm, and Peramium 



jmhesceiis. 



Redbud. See Cercis canadensis. 



Red root. See Ceanothus americanus. 



Rhamnus cathartica L. Buckthorn family ( Rhamnaceae ) . 



Buckthorn; hart's-thorn; way thorn. 



A shrub 6 to 15 feet high, introduced from Europe; escaped from hedges and 

 growing in dry soil in the New England and Middle States. 



Part used. — Berries (nonofficial). 

 Rhamnus purshiana. See Rhamnus purshiana DC. 

 Rhamnus purshiana DC. Buckthorn family (Rhamnaceae). 



Rhamnus purshiana; cascara sagrada; chittem-bark; sacred-bark; bearberry-tree. 



Small, indigenous tree, 15 to 20 feet in height, found on the sides and bottoms 

 of canyons. Rocky Mountains west to the Pacific Ocean, and extending north 

 into British America. 



Part used. — Bark, collected at least one year before being used (official). 



Rheumatism-root. See Dioscorea villosa and Jeffersonia diphylla. 

 Rheumatism-weed. See Ckimaphila umbellata. 



Rhododendron maximum L. Heath family (Ericaceae). 



Great laurel; rose-bay; deer-laurel; rose-laurel. 

 Tall, native, evergreen shruVj or small tree, found in low woods and along streams 



from Canada to Georgia. 

 Part used. — Leaves (nonofficial). 

 Rhus aromatica Ait. Sumac family (Anacardiaceae). 



Fragrant sumac; sweet-scented sumac. ^ 



. Indigenous shrub, 2. to 6 feet high, growing in woods and rocky situations, 

 C'anada to Florida, especially along the mountains, west to Minnesota and 

 Arkansas. 

 Part used. — Bark of root (nonofficial). 



Rhus glabra. See Rhus glabra L. 



Rhus glabra L. Sumac family (Anacardiaceae). 



Rhus glabra; smooth sumac; scarlet sumac. 

 Indigenous, branching shruV), from 4 to 12 feet high; in dry soil, thickets, and 



waste grounds nearly throughout the United States and Canada. 

 Parts u.ved. — Fruit (official) ; bark and leaves (nonofficial). 

 Rhus radicans L. « Sumac family (Anacardiaceae). 



Rhus toxicodendron (pharmacopo^ial name, 1890); poison-ivy; ]ioison-oak; 



poison-vine. 

 Native, woody vine, clinging to trees and fence rows; Canada to Florida, west 

 to Nebraska and Arkansas. Very poisonous to the touch. 



Part used. — Fresh leaves (official in U. S. P. 1890). 

 Rhus toxicodendron. See Rhus radicans. ■ ' 



a Rhus radicans L. was formerly believed to be a variety of Rhus to.i-icodendron L., ))iit tiie two are 

 now regarrled as distinct speeies, and the leaves from both have been used under the pliarmacoi»eial 

 name (U. S. P. 1890) Kluis toxicodendron. 



