Wild Flowers East of the Rockies 275 

 MILKWEED FAMILY (Asclepiadaceae). 



A family of stout-stemmed plants having milky 

 juices and ,usually, large opposite or whorled leaves. 

 They all have umbels of small flowers that are very 

 peculiar in construction and highly specialized for 

 cross-fertilization . by particular classes of insects. 

 Each blossom has five tiny structures shaped like 

 wish-bones, with pollen masses on each end. They 

 are so placed that the visiting bee or butterfly is pret- 

 ty sure of getting one or more of its legs caught in the 

 sharp angle at the apex and must, in order to get free, 

 tear the tiny arrangement from its support. He then 

 flies to the next plant with this dangling from his 

 legs. It is an unique method of forcing insects to 

 work for it, but one that never fails as far as the 

 plant is concerned, but sometimes proves a fatal trap 

 for insects lacking the strength to tear away the tiny 

 pollen saddle bags. We often find the corpses of 

 several such insects hanging from the flower cluster, 

 with their legs hopelessly entangled. 



BUTTERFLY-WEED; PLEURISY-ROOT; OR- 

 ANGE MILK-WEED (Asclepias tuberosa) is the most 

 brilliantly colored species of the genus. Even those 

 accustomed to the sight of this plant cannot sup- 

 press the feeling of admiration that stirs them as 

 they suddenly behold the vivid, orange flashes greet- 

 ing them as they cross waste or dry fields. 



The stem of butterfly-weed is usually erect, from 

 1 to 3 feet high; it is rather rough and has but little 

 of the milky juices so common to the other species. 

 The leaves are pointed-oblong, very short-stemmed or 

 seated oppositely. The beautiful orange flowers grow 

 in flat-topped clusters or umbels, at the summit of 

 the plant. It is found from Mass, to Minn, and south- 

 wards, most abundant in the Southern States. Its 

 roots are used medicinally. 



