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  • Integrated Pest Management
  • Protecting Pollinators
  • Invasive Species
  • Reducing Pesticides
  • Mosquito Control Program
  • Natural Lawns and Landscaping

Noxious Weeds - Myrtle Spurge

Noxious Weeds - Myrtle Spurge

Myrtle Spurge (Euphorbia myrsinites), also called "donkey tail" or "creeping spurge," is one of Colorado's "List A" noxious weeds, which requires it to be eradicated and prevented from propagating. A drought-tolerant perennial native to Eurasia, Myrtle Spurge was first introduced to North America as an ornamental. It is considered a noxious weed because it is aggressive and proliferates easily, outcompetes native plants, and has toxic milky sap.

Myrtle Spurge is a " List A" Noxious Weed under the Colorado Noxious Weed Act (35-5.5 CRS) and must be eradicated on all property.

Identifying Myrtle Spurge

Myrtle Spurge is an herbaceous plant with fleshy, waxy, grayish-green leaves that spiral around spreading, prostrate stems. It produces small yellow flowers in the early spring. When mature, it is 4 to 12 inches tall, with stems up to 18 inches long. Myrtle Spurge produces multiple new stems from the center taproot every year. See photos of Myrtle Spurge.

Myrtle Spurge Photo Gallery

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See full photo set in the Photo Gallery

Removing and Controlling Myrtle Spurge

On your property, Myrtle Spurge is easily removed by hand. Caution: Wear gloves, long pants, and a long-sleeved shirt when pulling. The weed exudes a milky sap that can severely irritate skin and eyes and is toxic if ingested.

  • Don't let children play with the weed! Wash skin and clothes after contacting it.
  • Pull myrtle spurge before it produces seed, which is viable for eight years. Pulling is more effective when the ground is moist and soft, such as after a soaking rain.
  • Wear long sleeves, long pants, gloves and eye protection. Spurge contains white sap that can cause severe skin irritation, including blistering (another reason to get rid of it!).
  • Remove at least four inches of the root when pulling myrtle spurge. The weed has a taproot, so the more of this you can pull out, the more effective it will be at preventing re-growth.
  • Bag the spurge and tie or fasten the bag closed.
  • Tell your neighbors and friends to purge their spurge too.
  • Bring your bags of spurge to Boulder Community Day and get free native plants in return.
  • Be committed! Follow-up treatments are important. The weed will likely need to be pulled for a few years before it is completely gone.

* Please do NOT compost noxious weeds in backyard compost piles since it will not reach high enough termpatures to kill weed seeds, which can then spread to your or your neighbors' yards. You can safely dispose of weeds with your other yard waste in curbside compost bins or at the yard waste drop at Western Disposal. They use an industrial composting process that kills weed seeds.

Plant Native Replacements

Plant native species in areas where Myrtle Spurge has been growing. Be sparing with fertilizer, which can give weeds an advantage over native species. Some native replacements are:

  • Colorado Four o'clock (Mirabilis multiflora);
  • Sulphur-flower Buckwheat (Eriogonum umbellatum);
  • Kinnikinnick (Arctostaphylos uva-ursi);
  • Creeping Barberry (Mahonia repens);
  • Four-nerve Daisy (Tetraneuris acaulis); and
  • Tufted Evening Primrose (Oenothera caespitosa).

More Information

To better understand how ornamental plants become weeds and why they are considered a problem, please review the background information provided on the Noxious Weed Ecology page.