Prostrate Knotweed

What it looks like

Forms a low, wiry mat spreading from a single taproot. Leaves are small, dull blue-green, and set alternately along the stems. Unlike spotted spurge, it has no milky sap when broken, and you'll notice a thin papery sheath wrapping around the stem at each leaf joint.

Often mistaken for: Spotted spurge (but spurge has milky sap; knotweed does not)

When it shows up in the Triangle

It gets going very early in spring, ahead of most other summer weeds, which means it's easy to miss if you're only watching for later germinators.

Where you’ll see it

Shows up in home lawns with thin or compacted soil, and commonly along walkways, driveways, and other high-traffic areas.

What you can do

• Core aerate to relieve soil compaction, since this weed is a strong sign of compacted ground
• Improve turf density with proper mowing and fertility so it can compete better
• Avoid heavy foot traffic on the same paths repeatedly
• Hand-pull young plants before they set seed, especially near walkways
• Topdress and overseed thin, worn areas to fill in gaps it likes to colonize