14 AMERICAN MEDICINAL LEAVES AND HERBS. 
EVENING PRIMROSE. 
Oenothera biennis L. 
Synonyms.—Onagra biennis (L.) Scop.; Oenothera muricata L. 
Other common names.—Common evening primrose, wild evening primrose, field 
evening primrose, tree primrose, fever plant, night willow-herb, king’s cure-ail,: 
large rampion, scurvish, scabish. | 
Habitat and range.—This is a widely distributed herb, its range extending from 
Labrador south to Florida and west to the Rocky Mountains. 1t usually frequents 
fields and waste places, oc- 
curring in dry soil. 
Description.—The even- 
ing primrose is a coarse an- 
nual or biennial weed, 
which has the peculiarity 
that its flowers do not open 
until evening, remaining 
open all night and closing 
the next morning, but not 
expandingagain. Itisgen- 
erally stout and erect in 
growth, from 1 foot to about 
5 feet in height, simple or 
branched, usually hairy 
and leafy. The leaves are 
1 to 6inchesin length, lance 
shaped and sharp pointed 
at the top, with wavy 
toothed margins narrowing 
toward the base. With the 
exception of some of the 
leaves near the base, most 
of them are stemless. The 
spikes of fragrant sulphur- 
yellow flowers are produced 
from about June to October 
and, as already stated and 
as indicated by the name 
‘‘evening” primrose, they 
are open late in the evening 
andduringthenight. They 
are borne at the end of the 
Fic, 6.—Evening primrose (Oenothera biennis), leaves, flowers, and stem and are interspersed 
capsules. with leafy bracts. Each 
flower has four spreading 
petals and measures about 1 to 2 inches across. The seed capsules are oblong and 
hairy, about an inch in length, and narrowed at the top. (Fig.6.) This plant belongs 
to the evening primrose family (Onagracez). 
, Collection, prices, and uses.—The entire plant is used. It is collected about flower- - 
ing time, bringing about 5 cents a pound. The herb has a somewhat astringent and 
mucilaginous taste, but no odor. It has been used for coughs and asthmatic troubles, 
and an ointment made therefrom has been employed as an application in skin 
affections. 
219 1A misleading name. 
