The Evening Primrose is commonly found in dry, open fields, and along roadways everywhere east of the Rocky Mountains, from June to October. The large, bright yellow flowers open in the evening, and after exhaling their fragrance for the benefit of the night-flying moths, they close the following day, and, after hanging withered for a day or two longer, drop away. Long before the potato was universally cultivated the fleshy root of this plant was used as a table vegetable. Years ago a strong decoction of this plant was highly esteemed for skin affections, and more recently a drug extracted therefrom has been commended in cases of asthma and in whooping-cough. Primrose ointment has been used for relieving itching and skin eruptions among infants. The rather stout, leafy, branching or simply hairy stalk rises from one to nine feet. The strongly ribbed, lance-shaped, alternating leaf tapers toward either end, and has an obscurely toothed margin. The lower ones are short-stemmed, and the upper ones are seated upon the stalk. Both leaf and stalk are often stained with purple. The flower has four flaring, heart-shaped petals, and eight long, golden-tipped, and spreading stamens. The four long, pale yellow sepals curve backward around the exceedingly long green calyx tube. The large green seed case is grooved and sticky. The flower buds are closely gathered in a terminal arrangement, and open only one or two at a time. As the flowering season nears the end, the blossoms seem to remain open much longer during the day, and this is attributed to the failing light of the autumn sun.
EVENING PRIMROSE. Oenothera biennis.