Euphorbia maculata L.

Euphorbia maculata plant

Family - Euphorbiaceae

Stems - From a thick taproot, herbaceous, erect to ascending or reclining, branching, sparse pubescent, with milky sap, to +45cm long, +30cm tall, typically becoming red in strong sun. Hairs of stem tomentoulose.

Euphorbia maculata stemStem with milky sap.

Leaves - Opposite, petiolate. Petioles to 2mm long. Blades oblique at the base, rounded at the apex, to +3cm long, 1.3cm broad, glaucous abaxially, deep green adaxially, shallow serrate, pilosuous. Margins often reddish. Most of the primary lateral veins arising from the base of the leaf.

Euphorbia maculata leavesPressed leaves.

Inflorescence - Single axillary cyathia. Pedicels to 4mm long, glabrous.

Euphorbia maculata inflorescence

Flowers - Glands of cyathia with white petaloid appendages. Appendages to .5mm long, .7mm broad. Involucre of cyathia glabrous, 1.5mm long. Pistillate portion of cyathium drooping. Styles 3, 1mm long, green, bifurcate. Ovary glabrous, green, 2mm broad in flower. Capsule 3-sided, 3-locular, glabrous. One seed per locule. Staminate flowers 2-5(11) per cyathium.

Euphorbia maculata flowersFlowers close-up.

Flowering - May - October.

Habitat - Thickets, fallow fields, gravel bars, cultivated fields, pastures, open woods, disturbed sites, waste ground, roadsides, railroads.

Origin - Native to U.S.

Other info. - This weedy species is found throughout Missouri. The plant is very common along roadsides and in disturbed areas. Many of the plants from this genus can be hard to differentiate. E. maculata can be a fairly big plant with fairly large leaves (for a spurge), which helps to identify it in the field.

Photographs taken at the Current River Conservation Area, Reynolds County, MO., 7-28-01, and in Ellington, MO., 7-7-03.