Algae on Bare Soil in Shady Lawn Areas

Thinning bermudagrass under increasing shade left bare, poorly drained soil where a black crust formed—algae. When dry it resembles a plastic sheet.

The fix is grading to improve drainage and amending with soil conditioner so desirable plants can outcompete algae. See also "Moss and Algae Control" for additional strategies.

portulaca is salt-tolerant