Myrtle spurge

Identification & Biology
Alias' : Donkey-tail, creeping spurge, wolf’s milk
Latin Name : Euphorbia myrsinites
Category : Terrestrial Plants
Description :
  • Evergreen perennial that grows 10-15 cm tall
  • Forms a low, spreading mound on the ground
  • Fleshy, blue-green alternate leaves that spiral around the stem
  • Flowers are inconspicuous, surrounded by yellow-green flower-like bracts
  • Leaves, stems, and roots all contain a milky white sap

 

Myrtle spurge is a succulent perennial that belongs to the spurge family (Euphorbiaceae). It is a popular ornamental plant for rock gardens, but when it escapes cultivation, it is a highly aggressive invasive species. Myrtle spurge blooms in April to May; after that the plant develops seed pods. When the seed pods dry, they release the seeds in bursts, sending them as far as five meters away! Seeds can remain viable in the soil for up to eight years. Although myrtle spurge primarily reproduces by seed, root fragments can also produce new plants. A distinctive characteristic of Myrtle spurge is its milky white sap that is toxic to both humans and animals.

Myrtle spurge can sometimes be confused with other members of the Spurge family, such as leafy spurge (Euphorbia esula) and cypress spurge (Euphorbia cyparissias). However, myrtle spurge can be distinguished by its succulent, blue-green alternate leaves that spiral around low-spreading stems.

Look Alikes
Habitat

Native to the Mediterranean, myrtle spurge prefers full sun and dry, well drained soils. It is drought tolerant and does well in poor, rocky soil. For this reason, it is commonly found in rock gardens, but it can escape and invade open areas such as fields, rangelands, gardens, disturbed areas, roadsides and waste places.

Impact & Risks
  • Myrtle spurge grows very quickly and aggressively.
  • It outcompetes native plants and reduces forage for wildlife.
  • It releases chemicals from its roots which stop other plants from growing near it.
  • All parts of the plant contain a white, milky sap that can cause irritation, blotching, blisters, and swelling in sensitive individuals.
Prevention & Mitigation

The most effective way to ensure that your lands do not become infested with myrtle spurge is by prevention. Here are some recommendations to prevent invasion: 

  • Maintain your crops and natural lands in a healthy, vigorous condition to ensure a competitive plant community. 
  • Do not purchase, trade, or grow myrtle spurge; suitable replacement species in the Okanagan include lance-leaved stonecrop, perennial bunchgrasses, and parsnip-flowered buckwheat.
  • Regularly patrol your property for myrtle spurge plants and immediately control or remove infestations before seed set.
  • Cooperate with adjacent landowners and encourage them to control myrtle spurge.
  • Immediately re-vegetate disturbed, bare soils with a suitable seed mixture that provides dense, early colonization to prevent weed invasion.
  • Ensure soil, gravel and fill are not contaminated. Do not move contaminated soils to a new area.
  • Remove plant parts and seeds from personal gear and clothing, also check and clean any equipment or vehicles before leaving an infested site.
Treatment & Disposal
  • Gloves and long sleeves should be worn at all times when dealing with myrtle spurge. Eyes should never be rubbed until after hands are thoroughly washed.
  • Hand pulling and digging can be effective for small patches if done prior to seed production. Remove as much of the root system as possible.
  • Bag or tarp any plants, plant parts and seeds and dispose of in your household garbage or at the local landfill.
  • Mowing can be effective in preventing seed production if timed properly.
  • Annual monitoring and re-treatment must be done to ensure complete removal.
  • Chemical control is also an option. Before applying herbicides, read the label for full use and precautionary instructions.  
  • For further information on the selection and application of chemicals to protect your crop, contact AgriService BC at 1-888-221-7141 or email AgriServiceBC@gov.bc.ca
  • Burning and composting is not recommended.
  • There are currently no biocontrol agents (natural insect enemies) for myrtle spurge in BC.
Okanagan Distribution

Priority Level Definitions

Watch For - Poses a significant threat (very high risk) and does NOT presently occur in the region OR is relatively new to the region and is very limited in extent.
High - High risk/impact; limited population with significant potential to spread in the region.
Medium - Medium risk/impact; limited distribution – broader population distribution with potential to spread further in a region.
Low - Low risk/impact; may be widespread or not, may be of concern in specific situations with certain high values – e.g. specific agriculture crops. Some species may be treated primarily with biological control agents.