Latin Name: Euphorbia esula
Physical Description: It is a long lived perennial herb from a heavy rhizome. It has an extensive root system that can extend 4.5m laterally and up to 9m deep. Plants can grow up to 1m tall and the stems contain a milky latex. The waxy leaves are attached directly to the stem and arranged alternately up the stem. The leaves have smooth edges and are bluish-green in color, turning yellowish or reddish-orange in late summer. The green flowers are small and comprised of 2 heart-shaped leaf like bracts. The flowers lack sepals and petals.
Habitat: It tolerates both dry and wet climates but appears best adapted to semi-arid areas. It is often found on roadsides, grasslands, open fields and disturbed areas.
Impacts: It can displace native vegetation, and threaten wildlife habitat, biodiversity and available forage for wildlife and livestock. It is toxic to humans and the milky latex can cause skin irritation upon contact. It is also toxic to cattle and horses and may result in excessive salivation, vomiting, colic and diarrhea if consumed; however they typically avoid eating the plant unless they are starving.
Reproduction: It reproduces primarily by re-sprouting from its extensive, persistent, creeping root system, but also by seed. A single stem may produce up to 250 seeds. When temperatures are hot enough, seed capsules explode, launching individual seeds up to 5 metres. Seeds o are capable of remaining viable in the soil for up to 7 years.
Mechanical: Hand pulling before seed production may be effective on small patches. Hand pulling must be repeated every 2-3 wees for several years. Use gloves while handling the plant to avoid skin irritations. Mowing is not effective in reducing infestations however may reduce seed production if mowed every 2 to 4 weeks. Cultivation has shown to be effective however may be labor intensive and long-term. Two cultivations in fall to a depth of at least 4 inches for 2 to 3 years will help reduce infestations. Cultivation every 2 weeks during the growing season and every 3 weeks during the late summer and fall for 2 or more years will reduce top grow and eventually stress the root system. Equipment must be cleaned after cultivation to avoid transporting root fragments.
Chemical: Several herbicides with the following active ingredients can control Leafy Spurge: 2,4-D, Aminocyclopyrachlor + Clhorsulfuron, Dicamba, Picloram, Glyphosate, Imazapic, and Imazapyr. For available products, contact your local agri-supply store. Prior to any herbicide application, read and follow the label instructions.
Biological: Aphthona nigriscutis is a root feeding flea beetle that helps weaken plants L by attacking and draining the root reserve of a plant. There are several other Apthona (flea beetle) species available.
Invasive Species Council of BC’s Leafy Spurge Factsheet
Provincial Biological Control Agents and Host Plants-Online Resource