This information
courtesy of the Colorado Natural Areas Program
Family: Euphorbiaceae (Spurge)
Other Names: graveyard spurge
USDA Code: EUCY2
Legal Status: Colorado Noxious
Weed List A (new in Colorado – call your county weed supervisor!)
Identification
Growth form:
Semi-woody perennial forb
Flower:
The tiny, lime green to white flowers are clustered in small, cup-like structures.
Seeds/Fruit: The three-capsuled fruits of cypress spurge explode at maturity, ejecting the seeds.
Leaves: Leaves are stalkless, alternate, narrow, linear to lance-shaped.
Stems:
Mature plants are about 1-1.5 feet tall.
Roots: The root system consists of long indeterminate roots, which spread both in horizontal and vertical planes, and short determinant roots, which spread in a strictly horizontal plane.
Seedling: No information available.
Other: The entire plant exudes white, milky sap that can be irritating to the skin.
Similar Species
Exotics: Can be distinguished from leafy spurge (Euphorbia esula) by its slender stems with numerous, crowded, narrow leaves.
Natives: None known.
Impacts
Agricultural:
Its milky latex is toxic, but it is rarely consumed in quantities sufficient to cause serious injury. Animals should not be pastured where spurges grow. It does not tolerate intensive cultivation and is not a problem in crops.
Ecological:
Cypress spurge is weedy plant that invades disturbed areas. Cypress spurge can reproduce rapidly, and quickly invade an area. Its ability to spread vegetatively is a major factor contributing to its success.
Human: Humans should be careful to avoid contacting the latex with bare skin.
Habitat and Distribution
General requirements:
Cypress spurge commonly occurs in dry to moderately moist meadows, pastures, forest edges, roadsides, rights-of-way, cemeteries, and gardens. Cypress spurge generally does not occur on intensively cultivated soils (Stahevitch et al. 1988).
Distribution:
Not yet widespread in Colorado.
Historical: Native to Europe.
Biology/Ecology
Life cycle:
Plants overwinter as seed or root and crown tissue. Perennating buds develop on the indeterminate roots (Stahevitch et al. 1988). New shoots emerge, and seeds germinate, each spring soon after the snow cover melts. Flowering begins the first or second week of May. Seeds may mature as early as the third week in June. A second flowering often occurs in late summer or early fall.
Mode of reproduction: Cypress spurge reproduces by vegetative propagation or seed.
Seed production:
Cypress spurge generally produces between 30-900 seeds per plant, which exhibit germination rates of 85% (Stahevitch et al. 1988).
Integrated Management
Summary
This species is not yet widespread in Colorado, and should be a priority for immediate eradication if found. Control of cypress spurge can be hard to achieve due to its extensive root system and highly efficient seed dispersal. As with other perennial rhizomatous species, an integrated control strategy should focus on eliminating seed production while depleting the nutrient reserves in the root system. Mechanical and/or chemical control should be combined with land management practices which maintain healthy native plant communities.
CONTROL
CEPEP
Weed Profile
References
Stahevitch, A.E., C.W. Crompton, and W.A. Wojtas. The biology of Canadian weeds. 85. Euphorbia cyparissias L. Canadian Journal of Plant Science 68:175-191.
Whitson, T.D.(ed.), L.C. Burrill, S.A. Dewey, D.W. Cudney, B.E. Nelson, R.D. Lee, R. Parker. 1996. Euphorbia spp. Weeds of the West. Western Society of Weed Science, in cooperation with the Western United States Land Grant Universities Cooperative Extension Services, Newark CA. pg. 312.
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