sun spurge
Family
EuphorbiaceaeScientific Name
Euphorbia helioscopiaOther Common Names:
madwoman's milk
Synonyms (former Scientific Names):
Galarhoeus helioscopius
Tithymalus 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