Spotted spurge is the low, flat weed that spreads in sidewalk cracks, garden beds, and thin lawns all over the United States—look for a dark red spot in the middle of each tiny leaf. It's a native North American annual, and broken stems ooze a milky sap that can irritate skin and eyes. It's also called spotted sandmat.
Appearance
- Growth form
- A fast-growing summer annual that lies flat and can form a dense mat up to about 3 ft (90 cm) across. Stems are reddish and hairy, and the taproot can reach more than 2 ft (60 cm) deep.
- Leaves
- Leaves are opposite, oval, and small—usually under ½ inch (about 1 cm) long—with finely toothed edges. Most plants have a dark red or purplish spot in the middle of the leaf.
- Flowers
- Tiny flowers sit in the leaf joints in summer. What looks like one flower is actually a small cup holding several very reduced flowers, edged with four white to pink petal-like flaps.
- Fruit
- The fruit is a tiny three-sided capsule, about 1/16 inch (1.3 mm) long, covered in short hairs.
Look-alikes
| Growth | Leaf spot | Hairs | |
|---|---|---|---|
| Spotted spurge | Flat mat | Usually a dark red spot | Hairy stems; fruit hairy all over |
| Ground spurge | Flat mat | None | Fruit hairy mainly on edges |
| Creeping spurge | Flat mat, roots at joints | None | Hairless |
| Nodding spurge | Upright, to 3 ft | — | Fruit hairless |
Where it lives
- Typical habitats
- Sidewalk cracks
- Garden beds
- Lawns
- Roadsides
- Farm fields
- Range
- Native to North America and considered native throughout the lower 48 states. It's the most common spurge in California. It has also spread to South America, Europe, Asia (including Japan and Korea), Africa, Australia, and New Zealand.
- Preferred conditions
- Grows best in full sun and handles disturbed, coarse, or poor soil. It's often one of the first plants to move into bare ground.
Growing it
- Care
- In gardens, pull plants before they set seed—they often snap at the stem and regrow, so get the root. Mowing doesn't help because it grows so low. A mulch of bark, compost, or straw at least 2 inches (5 cm) deep helps keep seedlings from coming up.
- Propagation
- Spreads only by seed. One plant can make several thousand seeds, and it can start making seed just 5 weeks after sprouting. Seeds sprout best in warm soil, 75–85°F (24–29°C), and need light, so seeds buried deeper than ½ inch rarely come up.
- Toxicity
- The milky sap can irritate skin and eyes, and sun exposure can make the irritation worse. Wear gloves when pulling it. It's poisonous to livestock; sheep grazing where it dominated have died after eating it.
Name and classification
- About the name
- You may see it listed as Chamaesyce maculata, from a time when the sandmats were treated as their own genus. The name "prostrate spurge" is sometimes used for it too, but that name also belongs to Euphorbia prostrata.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
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