Algae

Slimy, black crust on the surface of thinned, wet areas, with small circular patches of thinning or yellowing turf.

The symptoms of blue/green algae on putting greens include the appearance of small, circular patches of thinning or yellowing turf. These patches can range from the size of a tennis ball to several inches in diameter. The affected areas may also have a slimy, black crust on the surface. These symptoms can be severe and can lead to general thinning or even death of the turfgrass in the affected areas.

The signs of blue/green algae on putting greens include the presence of black mucilage, which helps the algae survive under dry conditions, and a slimy, black crust on the surface of the affected area. Additionally, the algae may be visible as individual cells or filaments called "trichomes" which are arranged in a filamentous form and are photosynthetic organisms without a vascular system.

Algae are photosynthesizing organisms that lack a vascular system. Blue/green algae contain chlorophyll A and phycobilin pigments and the cyanobacteria produce individual cells, typically 1-3 x 1-40 um. These cells are arranged in filaments called "trichomes." Heterocytes algae fix atmospheric nitrogen or akinetes; and cyanobacteria, such as Oscillatoria spp., have "gliding" motility.

The ideal conditions for blue-green algae to thrive include overcast weather, excessive moisture, exposed soil, mechanical stress or thin areas, and high levels of phosphorous.