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MILKWEED FAMILY (Asclepiadacece) 

 BUTTERFLY-WEED (Asdepias tuberosa L.) 



COMMON NAMES: The butterfly- weed is also known by the naim - 

 pleurisy-root, orange-root, Canada-root, orange swallow-wort, yellow 

 milkweed, Indian-posy, silk-weed. 



DESCRIPTION: The butterfly-weed is an erect, stout, perennial herb. 

 The stem is simple or branched near the top, hairy, very leafy, from one 

 to two feet high. The leaves are alternate, oblong, pointed or sometime- 

 rounded at the apex, very short-stalked or without stalks, two to six 

 inches long. The greenish-orange flowers are arranged in terminal umbels, 

 the stalks of which are shorter than the leaves. The seed-pods, or follicles, 

 are very striking and characteristic of all the milkweeds. They are from 

 four to five inches long and one to one and a half inches wide in the middle, 

 tapering at both ends, and covered with fine hairs. The numerous seeds 

 are flat, reddish-brown, with a long tuft of fine silky down. They may be 

 seen in the autumn and early winter escaping from the partially opened 

 pod and being blown some distance by the wind. The handsome orange 

 flowers are in bloom from June to September. 



DISTRIBUTION: Native to Canada, it is found on dry fields and banks, 

 chiefly in the province of Ontario. 



POISONOUS PROPERTIES: The leaves and stem are poisonous. They 

 contain the amorphous, bitter glucoside asclepiadin. Horses and cattle 

 avoid eating the plant, but sheep are sometimes poisoned when driven 

 over dry districts where other herbage is scarce. 



OTHER SPECIES OF MILKWEED IN CANADA. 

 PLATE XXXII. 



The swamp milkweed (A. incarnata L.); the common milkweed (A. 

 syriaca L.), the showy milkweed (A. speciosa Torr.), and the oval-leaved 

 milkweed '(A. ovalifolia Dec.), all natives of Canada and similar in general 

 appearance to the butterfly weed but with opposite leaves, which is the 

 usual arrangement with most of the milkweeds, are said to be more or less 

 poisonous and must be viewed with suspicion until more is known of them. 



