SUMACH FAMILY 



from Nova Scotia to Florida and westward to Minne- 

 sota, Nebraska, and Arkansas. The compound leaves 

 have three leaflets, so that they are very easily distin- 

 guished from those of the Virginia Creeper, PartJicno- 

 cissus qiiinqucfolia, which has five palmate leaflets; and 

 from the Bitter Sweet, which has seven to nine pinnate 

 leaflets. These Poison Ivy leaflets are ovate or rhom- 

 bic, entire or sparingly sinuate, the apex acute or acu- 

 minate; the lateral ones almost sessile; the terminal 

 stalked. The flowers are green and borne in loose 

 axillar}' panicles ; the fi'uit is like that of RJiiis ver?iix. 

 The plant is poisonous to the touch, and should be 

 avoided. All the poisonous species of Rhus ought to 

 be extirpated root and branch, but instead of that they 

 are increasing. This is largely due to the immunity 

 they enjoy because people are afraid to touch them ; 

 but in Avinter probably they could be easily and safely 

 destroyed ; destroyed they certainly should be. 



POISON IVY. NORTHERN POISON OAK 



Rhus microcdrpa. Rhus toxicodendron. 



The two plants now known as Rhus radicans and 

 RJlus microcarpa were formerly considered as a single 

 species and described under the name RJius toxicoden- 

 dron, which name is now given to a third species of 

 southern habitat. The plant popularh^ known as Poison 

 Ivy is the running vine so abundant in fields and by the 

 roadsides throughout the north. The stem often trails 

 upon the ground and sends up erect branchlets six or 

 eight inches high which make a tiny thicket; some- 

 times the entire plant is erect but low. The leaves are 



86 



