Ontario Weeds: Cypress
spurge
Table of Contents
- Name
- Other Names
- Family
- General Description
- Stems and Roots
- Flowers and Fruit
- Habitat
- Similar Species
- Caution
- Related Links
Name: Cypress spurge, Euphorbia cyparissias
L.,
Other Names: euphorbe cyprès,
Graveyard spurge, Graveyard weed, Poor man's-hedge, rhubarhe des
pauvres
Family: Spurge Family (Euphorbiaceae)
General Description: Perennial reproducing
by seed and from widely spreading, much-branched underground roots
with numerous pink buds and forming dense stands.
Photos and Pictures
Stems & Roots: Stems erect 10-80cm
(4-32in.) high, usually much-branched above; leaves alternate (1
per node), very numerous, small, narrow, linear or club-shaped;
tip of stem at beginning of inflorescence (flowering branches) with
a whorl of 10 or more shorter leaves.
Flowers & Fruit: Flowers yellowish-green
on a many-branched umbel (usually 10 or more main branches) at the
tip of the main stem and on the upper branches; leaf-like bracts
of the inflorescence short and broad, heart-shaped, tapering towards
the pointed tip, at first light yellowish-green but usually turning
reddish-green towards maturity; flowers very small, unisexual, without
sepals or petals, and crowded together in a complex structure called
a cyathium, like those described for Leafy spurge); one little cyathium
between each pair of bracts throughout the inflorescence; each flower
cluster producing a 3-lobed seedpod containing 1 to 3 egg-shaped,
smooth, grayish seeds 1.5-2mm (1/16-1/12in.) long. The whole plant
contains an acrid sticky white juice. Flowering begins in late spring
or early summer and may continue intermittently until late autumn.
Habitat: Two kinds of Cypress spurge
occur in Ontario, a sterile diploid form which does not produce
viable seed, and a fertile tetraploid form which produces abundant
fertile seed. The sterile form, reproducing only from underground
parts was once commonly cultivated in gardens and cemeteries. It
has persisted in many localities and occasionally spreads vegetatively
to surrounding roadsides and waste places. This form occurs throughout
Ontario. The fertile form which can reproduce by seed as well as
by underground parts has become a rampant and troublesome weed in
Dufferin County and in the Braeside area of eastern Renfrew County,
occupying hundreds of hectares of pasture, abandoned cultivated
land, woodland, and roadsides.
Similar Species: It is distinguished
from most other plants by its milky juice, its spreading perennial
roots with pink buds, its numerous, small slender leaves, and its
yellowish-green inflorescence, from the upright annual spurges (Petty,
Sun and Broad-leaved) by its perennial habit, and from these and
Leafy spurge by its slender stems with numerous, crowded, narrow
leaves, its umbel with usually more than 10 slender branches from
the tip of the main stem, its heart-shaped bracts or leaves in the
inflorescence tapering towards the tip, and by the production of
densely leafy branches after early summer flowering.
Caution: Although sheep can be forced
to eat Cypress spurge and may develop a preference for it, the literature
suggests it may be toxic to cattle and horses. The milky juice can
be irritating on bare skin and cause a potentially serious rash
for some people.
Related Links
... on general Weed
topics
... on weed identification, order OMAFRA
Publication 505: Ontario Weeds
... on weed control, order OMAFRA
Publication 75: Guide To Weed Control
| Back
to the Ontario Weeds Gallery |
