sun spurge

Family

Euphorbiaceae

Scientific Name

Euphorbia helioscopia

Other Common Names:

madwoman's milk

Synonyms (former Scientific Names):

Tithymalus helioscopius

Galarhoeus helioscopius

Leaves

The leaves of the upper stem appear whorled but usually occur in groups of 2 or occasionally 3. Leaves are oppositely arranged along the stem. Leaves are widest at the apex and taper to the base (oblanceolate). Leaf apexes are are very finely toothed or serrated. All leaves generally attach directly to the stem and do not occur on petioles (sessile).

Identifying Characteristics

A winter annual that grows prostrate along the ground with tips and upper stem portions ascending (decumbent growth habit). All parts of the plant emit a milky sap when cut. The distinctive red stems, leaves with finely toothed leaf apexes, and milky sap are all characteristics that help in the identification of sun spurge. From a distance, this plant might be confused with Cypress Spurge (Euphorbia cyparissias), which has very similar flowers. However, the leaves of cypress spurge are much more linear than those of sun spurge and upon closer examination distinguishing between the two species is relatively easy.

Flower Seed Head

Inconspicuous, light green to pale yellow in color. inflorescences (cyathias) occur at the ends of stems and are 4-lobed. Each lobe has a round yellowish gland.

Seed Fruit

A very distinctive 3-parted capsule (3-4 mm long) that contains a single, 2 mm long dark brown seed.

Where Found

Sun spurge is a somewhat rare weed of pastures, hayfields, and winter small grains in Virginia.

Growth Habit

prostrate and nonwoody

Thorns or Spines

not present

Approximate Flower Diameter

Varies:

pencil,

dime

Dominant Flower Color

Varies:

yellow,

green

Flower Symmetry

radial symmetery

Leaf Hairs

no hairs

Leaf Shape

lance

Leaf Arrangement

Varies:

opposite,

whorled

Leaf Margin

serrated

Leaf Structure

simple

Leaf Stalk

none

Stem Hairs

has hairs

Stem Cross Section

round or oval

Milky Sap

present

Root Structure

Varies:

fibrous,

taproot

Life Cycle

winter annual

Ochrea

not present

Plant Type

Herb