Yellow Rattle

(Rhinanthus minor)

Yellow Rattle (Rhinanthus minor L.)

Identification: Flowers yellow with a tubular corolla. Upper 2 petals lobes fused into a convex, hood-like structure. Lower 3 petal lobes fused into a lower 3-lobed banner. Upper hood sometimes tinged with violet and lower banner spotted. Calyx forming a flat bladder-like envelope around the base of the flower, swelling when in fruit (the rattle). Flowers found in upper leaf axils. Stems smooth. Leaves ovate, with a heavily toothed outer margin, sessile to the stem. Plant 8 to 20 inches in height.

Distribution: Across Canada from Newfoundland to Alaska. Enters the eastern United States from New England to New York, and Wisconsin. Found in the west along the Rocky Mountains to New Mexico and on the Pacific Coast to Oregon. Also lives in northern Europe and Asia.

Habitat:Yellow Rattle is found in fields and thickets.

Flowering period: June to September.

Similar Species: The yellow flowers, the swollen calyx, and the ovate, heavily toothed leaves are distinctive.