Cypress spurge

Euphorbia cyparissias

Images of this species:

Common look-alikes:

Identification

Appearance

Euphorbia cyparissias grows up to 12 in. (30.5 cm) tall. This herbaceous, perennial plant invades open disturbed areas throughout the United States. All parts of the plant exude a white, milky sap when broken.

Foliage

The leaves are small, up to 1 in. (2.5 cm) long. The leaves are numerous, alternate or whorled, bright green, and linear in shape.

Flowers

Yellow-green, inconspicuous flowers are in a cyme at the top of the plant. Flowers mature to red.

Fruit

The fruit is three-lobed and contains 1-3 egg shaped smooth gray seeds that measure 0.06-0.08 in. (1.5-2 mm). Euphorbia cyparissias produces large clonal colonies through an extensive underground root system, that allows this plant to reproduce with lateral root buds.

Biology

This is considered a watch list species.

Origin

Native to Eurasia

Habitat

Abandoned Field, Agricultural Field, Edge, Open Disturbed Area, Pasture, Railroad Right-of-Way, Roadside, Utility Right-of-Way, Vacant Lot, Yard or Garden. Euphorbia cyparissias is most often found in old fields and natural grasslands.

Life cycle

Plants overwinter as seed or root and crown tissue. Over-wintering buds develop on the indeterminate roots. 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.

Ecological Threat

Euphorbia cyparissias can invade open disturbed areas such as fields, pastures, agricultural land, roadsides, and yards. It is toxic to livestock so infestations reduce the forage value of pastures and contaminates hayfields. The white, milky sap can be irritating to skin and should be avoided. It can form huge infestations displacing native vegetation. This plant is native to Europe and western Asia. It was first introduced into the United States in the mid-1800s as an ornamental.

Management Options

Mechanical Control

  • Cypress spurge may be controlled by frequent and repeated hand-pulling or mowing, and cypress spurge does not tolerate prolonged cultivation.

  • Fertile cypress spurge types were controlled by monthly hand-pulling for a year

Chemical Control

  • Control of cypress spurge with herbicides has shown variable success, which may be related to the cypress spurge type, application method, and/or timing of posttreatment evaluation.
  • Cypress spurge's waxy cuticle layer, a surfactant is required for absorption, and that a combination of herbicides may effectively control cypress spurge.
  • Be careful not to damage or kill nearby native plants when conducting management work. And when using herbicides, always follow the instructions on the label.

Citations

Photo Credit

5447543, 5447548, 5447560, 5447547, 5447605, 5447635, 5447414, 5447569, Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

5207004, Todd Pfeiffer, Klamath County Weed Control, Bugwood.org

Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

 

Information Credit 

Go Botany, Euphorbia cyparissias

Invasive Plant Atlas of New England

U.S. Forest Service 

Colorado Weed Management Association