Tread softly

Cnidoscolus stimulosus
Family: Euphorbiaceae

Natural History
White flowers and deeply-lobed leaves of tread softly
Photo credit: SFRC, University of Florida

Tread softly, also called bullnettle, spurge nettle, or finger-rot, is one southeastern native to beware of. The tiny stinging hairs that cover the plant can cause a reddish rash and painful, stinging sensation if they are touched. While the effects are not serious, the pain may persist for up to an hour. This is a member of the family Euphorbiaceae, or spurge, which is known for its toxic substances. Some Euphorbes have toxic sap, latex, or seed oils, while others, like this one, have venomous hairs. The tubers of the plant are edible but the upper portions should be avoided.

Bob-white quail and several species of songbirds consume the seeds of tread softly. Wildlife are the primary dispersers of the seeds, however, the plants re-grow prolifically from the fleshy, persistent tap root.

Tread softly is found in coastal plains from Virginia to southern Florida and west into Oklahoma, Texas, and Louisiana.

This plant is occasionally called "stinging nettle," but that common name is usually reserved for Urtica dioica and other plants of the genus Urtica in the family Urticaceae.


Identifying Characteristics

Habitat: Tread softly grows in dry, sandy soils, such as old fields, roadsides, disturbed sites, pine forests and dry, wooded areas.
Size/Form: Tread softly is an erect, weedy perennial that grows to 3' tall and is covered with tiny, stinging hairs. The stem is stout and branches into a V-shape, with numerous branches.
Stem: The stems of the plant are stout and sheathed in spiny, toxic hairs.
Leaves: The leaves are simple, alternately arranged, and palmately-lobed with 3 to 5, deep, toothed lobes. Their shape is similar to that of a maple leaf. Whitish veins are evident on the dark green leaf surfaces, while the undersides and margins are covered with venomous, stinging hairs.
Fruit: The fruit is a spiny, spherical, or cylindrical capsule with three chambers that open to release dark brown seeds. The pod-like capsules are covered with stinging hairs.



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