(Euphorbia marginata), succulent plant of the spurge family (Euphorbiaceae), native to the central plains of the United States. The plants, which grow to a height of 60 cm (2 feet), have long, oval, light green foliage, with white-margined leaves near the top, where several white whorls of bracts (leaflike structures) are clustered. The plant has long been a favourite as a garden annual and in flower arrangements, but some people are allergic to its white latex sap.