Flowers are pink to lavender and are produced in the axils of leaves and stems. Prostrate knotweed is a low-growing summer annual that is well adapted to compacted, highly trafficked areas such as along sidewalks, in athletic fields, and in golf course cart paths. Each leaf is elliptical, tapering to a rounded tip. Stems grow prostrate but do not root at nodes. One distinct feature of knotweed is the papery sheath at the base of each leaf.
Flowers are very small and white, and grow in the leaf axils.
When broken or cut, the stems exude a white, milky substance. Flowers of spotted spurge are very small and pink or white. This species is common in newly established turf and frequently occurs in mature turf that has been thinned by insect attack. Stems are thick, sprawling, and red. Leaves are thick and fleshy, light green and wedge-shaped.