Synonyms: Euphorbia esula
Common Names: Spurge
Description: This species is listed as a prohibited noxious weed by the Michigan Department of Agriculture; deep taproot, up to 4.5 m (15 ft) deep; tough, woody extensive root system may extend up to 10 m (33 ft); large root reserves allow plant to recover from most disturbances.
Habit: Herbaceous perennial ranging in height from 15-92 cm (6-36 in); root system can extend up to 6 m (~20 ft).
Leaves: Simple, alternate, long, narrow, bluish green in color, usually pointed and drooping with smooth margins, exude white milky sap when crushed.
Stems: Upright stems that branch towards the top of the plant; dry stems may persist into the winter and following summer; stems also release white, milky sap when broken.
Flowers: Small, yellowish-green in color, fused petals form a cuplike structure; blooms mid-June through late-July.
Fruit and seeds: Smooth, oblong, gray-brown seeds in explosive capsules; one plant can produce up to 200 seeds; high germination rate; viable up to 8 years with adequate moisture.
Habitat: Roadsides, prairies, savannas, gravel pits, open areas.
Reproduction: By seed. Also spreads rapidly though its persistent root system from crown and root buds that over-winter under the soil surface.
Similar species: Flowering spurge (
Euphorbia corollata) has white flowers and erect leaves; non-native Cypress spurge(
Euphorbia cyparissias) has stem leaf blades less than 2.5 mm wide.
Monitoring and rapid response: Monitor open sites and woodland edges, early detection is critical. Leafs out early in spring; bright yellow-green bracts appear in late May or early June. Seedlings develop buds within 7-10 days of emergence. Long shoots spread laterally; pulling, digging, burning and tilling may cause them to increase. Foliar herbicide treatment provides effective control of small occurrences. Surveillance and control efforts needed for 5-10 years.
Credits: The
Michigan Natural Features Inventory (MNFI) has partnered with MISIN to provide the information in this fact sheet. Species images and/or information were used with permission from "
A Field Identification Guide to Invasive Plants in Michigan's Natural Communities" and "
A Field Guide to Invasive Plants of Aquatic and Wetland Habitats for Michigan.