Overview
Spotted spurge is a low-growing plant native to eastern North America that is considered a weed in gardens, cultivated agricultural areas, and disturbed sites. It will grow in almost any open area, including waste ground, roadsides, pastures, open woods, in sidewalk cracks and in thin lawns. It often grows in poor, compacted soil and generally in full sun. This summer annual in the spurge family (Euphorbiaceae) can overgrow and smother desirable plants. Other common names include spotted euphorbia, spotted sandmat, milk-purslane, and prostrate spurge. The taxonomy of this group of plants is rather confusing, partly because many of the species are similar in appearance. Authorities consider them to be in the genus Euphorbia, though some assign them to the genus Chamaesyce. Other scientific names listed for this plant include Chamaesyce maculata and E. supina .
Identification
Spotted spurge forms a rangy to dense mat of foliage radiating from a central taproot up to two feet long. Plants are prostrate to ascending and under ideal conditions a single plant can grow up to 3 feet across. Seeds germinate best in warm soil when temperatures are above 75 °F, although it will sprout at cooler temperatures when moisture is available. The seeds need light to germinate, so seeds more than half an inch deep in the soil are unlikely to germinate. These low-growing plants tend to develop slowly and often are not noticed until late summer. Plants are killed by frost.
The ovate, slightly hairy, dark green leaves grow in opposite pairs along pink to maroon, hairy stems. The leaves usually have a red spot in the middle of the upper leaf surface but this marking is not always present (<5% of plants may lack it). The stems branch out from a central point and do not root at the nodes. They secrete a milky sap (characteristic of the euphorbia family) when broken. The sap is a skin irritant to susceptible people and is highly toxic to sheep.
The tiny, relatively inconspicuous flowers are grouped in cyathia in the leaf axils where the leaves join the stems. Each flower lacks petals, having only stamens or pistils.
Several male and one female flower are aggregated into each cup-like cyathium with white to pink petaloid appendages. The flowers are followed by small fruits. The tripartite seed capsule contains one seed in each of the three locules. Each minute brown seed (1mm long or less) is distinctly hairy with longitudinal ridges or wrinkles. The seeds are hydrophilic, sticking to surfaces (like animal fur, clothing, footwear, etc.) when they get wet , which helps disseminate the seeds). Spotted spurge produces seeds quickly and prolifically. Plants can begin producing flowers and seeds in just over a month after germination under ideal condition. Thousands of seeds are produced by each plant, which can germinate immediately, the following spring, or remain dormant in the soil for years.
Management Strategies
The best methods for controlling spurge in gardens are to prevent germination by mulching and to remove plants as soon as they are noticed. Organic mulches, such as shredded bark, compost, or straw at least 2 inches thick will eliminate the light needed for spotted spurge seed germination. If plants do sprout, hand pull or hoe them out, preferably before they produce seed. Loosen the soil beneath the foliar mat to remove the root, as the plant can regrow from the crown if the stems are just broken off. Wear gloves when hand pulling to prevent getting sap on the skin, as the sap can be a skin irritant for sensitive individuals; also, the sticky sap is relatively hard to wash off. Avoid purchasing ornamentals that have spotted spurge growing in the containers, to avoid introducing seed into your garden.
Pre-emergent herbicides can be used in areas where spotted spurge has been an ongoing problem and mulching is not feasible. Do not use pre-emergents in vegetable gardens unless the product is labeled for use on food crops. Pre-emergents are only effective before seeds germinate, so apply them before soil temperatures exceed 60 °F. Non-selective herbicides, such as glyphosate, can be used on larger plants, taking care to avoid contact with desirable plants. If only the foliage is killed, plants may grow back from the roots. Always read, understand, and follow herbicide product label directions and precautions.
Spotted spurge is only a problem in thin lawns, so the best way to prevent it from becoming a lawn weed is to maintain a thick, healthy turf through sound cultural practices including proper mowing, fertilization, and irrigation. Core aerating will help alleviate soil compaction issues. Small infestations in lawns can be removed by hand, but for more widespread infestations, selective broadleaf herbicides may be more practical.
Author: Susan Mahr, University of Wisconsin—Madison
Reviewers: Bruce Spangenberg, Horticulture Outreach Specialist, Allen Pyle, Horticulture Outreach Specialist, UW—Madison Extension
Revised: July 2026
