Northern Prairie Wildlife Research Center
Northeast Wetland Flora
Field Office Guide to Plant Species
Euphorbia humistrata Engelm.
- Family: Spurge (Euphorbiaceae)
- Flowering: July-October
- Field Marks: This small spurge has hairy stems, ovaries, and capsules, smooth seeds, and
the main stem leaves less than twice as long as wide, and the branch leaves narrower.
- Habitat: Moist soil, along rivers.
- Habit: Annual herb with a taproot.
- Stems: Lying flat or ascending, branched, hairy, spreading up to 3 feet across.
- Leaves: Opposite, simple, ovate-oblong to elliptic-oblong, rounded at the tip, asymmetrical at the nearly sessile base, finely toothed to toothless, hairy or smooth, up to 3/4 inch long.
- Flowers: Clustered in the axils of the leaves, consisting of 4 glands and either stamens or pistils.
- Sepals: Male flower: 0 sepals; female flower: 3-6 minute, united sepals.
- Petals: 0.
- Stamens: 1.
- Pistils: Ovary superior, hairy.
- Fruits: Capsules nearly spherical, hairy, 3-angled, up to 1/10 inch in diameter; seeds oblongoid, 4-angled, smooth.
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