Moss

What it looks like

A dense, velvety or feathery green carpet, sometimes yellow-green, that sits right on the soil surface with no real roots. It fills in where grass has thinned out and holds up well under foot. Moss does not crowd out healthy grass; it grows where grass already can't.

Often mistaken for: Algae (a dark, slimy crust on bare wet soil), or a thin lawn with no moss yet

When it shows up in the Triangle

Most noticeable from late fall through early spring in the Triangle, when it is cool and wet and the grass is barely growing. Summer heat can dry it out and turn it brown, but it comes right back with fall rain unless the conditions change.

Where you’ll see it

Shaded spots under trees, the north side of houses, compacted paths and play areas, low wet spots, and acidic, low-fertility soil, which describes a lot of Piedmont red clay.

What you can do

• Take a soil test (free through NC State most of the year) and lime only if it calls for it; low pH alone rarely explains moss
• Open up the shade: limb up or thin trees so the area gets at least 4 to 6 hours of sun
• Core aerate compacted areas and fix drainage in low spots that stay wet
• Mow tall fescue at 3 to 4 inches and feed it on a fall schedule so it can compete
• Rake out the moss and overseed in September or October; if nothing else changes it will come back
• In deep shade, consider a shade groundcover or mulch instead of fighting for grass