ASCLEPIADACEAE (MILKWEED FAMILY) 315 
BUTTERFLY WEED 
Asclépias tuberdsa, L. 
Other English names: Orange Milkweed, Orange root, White Root, 
Pleurisy Root, Wind Root, Swallow-wort. 
Native. Perennial. Propagates by seeds. 
Time of bloom: June to August. 
Seed-time: August to October. 
Range: Ontario to Minnesota, southward to Florida, Texas, and 
Arizona. 
Habitat: Dry fields and pastures. 
The most showy of the Milkweeds. 
Where abundant, the plant 
may be made to pay for the cost of its suppression by the sale of 
its white, tuberous roots, which are 
valuable medicinally and bring six 
to ten cents a pound in the drug 
market; they should be collected in 
autumn, when well stored with sus- 
tenance for the winter. 
Stems several from the clustered 
tubers, one to two feet high, erect, 
branched at the top, round, and 
very hairy; they lack the milky 
juice so characteristic of the family. 
Leaves alternate, oblong to lance- 
shaped, acute or sometimes obtuse 
at apex, entire, hairy on both sides, 
sessile or with very short petioles. 
Flowers in large flat-topped umbels 
terminating stem and branches, bril- 
liant orange in color; butterflies of 
many kinds are nearly always hover- 
ing about them; the five lower seg- 
ments of the corolla are reflexed 
a 
Fig. 220. — Butterfly Weed 
(Asclepias tuberosa). X 4. 
and the crown above it has five small, spreading hoods, each 
of which has within it a slender, incurving horn. Stamens five, 
inserted on the base of the corolla, the filaments forming a tube 
which incloses the pistil, the anthers adherent to the stigma; 
ovaries two, with very short styles connected at the summit by 
