234 WEED FLORA OF IOWA 



Cow Parsnip (Heracleum lanatum Michx.). 



Description. — A stout, hairy, pubescent perennial 4-8 ft. high.; 

 leaflets broad and large, irregularly cut-toothed; flowers white, in 

 broad umbels. 



Fig. 134. 



Cow Parsnip (.Heracleum lanatum) . Common in woodland pastures. 

 (Photographed by Charlotte M. King.) 



Distribution. — From the Atlantic coast, Newfoundland, through 

 the northern states and Allegheny mountains to California. Com- 

 mon in the Rocky mountains. 



APOCYNACEAE, DOGBANE FAMILY. 



In the tropics several species are important rubber producing 

 plants. They are commonly called milk-weeds in Iowa. 



