Leafy spurge Euphorbia esula L.
Family: Euphorbiaceae (Spurge family)
Life cycle: Perennial reproducing by seed and rhizomes.
Native status: Introduced from Europe/Asia.
Habitat: Pasture, roadsides, prairies; more prevalent in western Iowa
General description: Erect, branching plant reaching heights of 3 ft. Stems and leaves emit white sap when cut. Leaves are alternately arranged, linear to lanceolate, up to 4 in long with smooth margins. Flowers arranged in an umbel and are surrounded by showy, yellow-green bracts.
Key ID traits: Milky sap, linear leaves.
Similar species: Cypress spurge has a similar growth habit, but is much smaller and leaves are 1 to 1.5 in long and much narrower than those of leafy spurge.
Miscellaneous: Leafy spurge has been one of the largest problems in rangeland of the northern plains. It is moving into Iowa from the west, and seems to be spread primarily via highway construction. There has been success with biological control in western states following introducing of several insects from leafy spurge’s native region.