Moss in a lawn indicates a basic fault in that lawn. Moss never invades a dense, vigorously growing turf. It merely occupies space where grass is not growing. The presence of moss is usually associated with low fertility, poor drainage, low soil pH, improper watering, too much shade, soil compaction or a combination of these factors. Lack of fertility and poor drainage are the most common causes of moss invasion.
A regular balanced fertilizer program will go a long way toward preventing moss.
Established moss may be removed by hand raking or rototilling. After the moss has been removed, be sure to correct the basic cause and follow with routine good management practices that will produce a dense, vigorous turf.
Algae may be found growing in moist areas under trees where it is often mistaken for moss. It is a fresh water plant which can be eliminated by the same methods described for moss.
Algae will return if the causal factor, usually poor drainage, too much shade, or low fertility is not corrected.
Mushrooms, puffballs or toadstools may become a nuisance in lawns at certain times of the year.They usually occur during wet periods. The fleshy fungi usually grow on decomposing organic matter in the soil. Often the organic matter may be a buried stump, root, or board. These fungi are good wood rotters. They may also be breaking down organic matter which is mixed with the soil.
Generally raking or breaking up with the lawn mower is a satisfactory but repetitive remedy.
There is a specific fungus growth of toadstools known as a Fairy Ring. Grass just inside or outside the circular band where the fungus grows often is stimulated to rapid growth with a dark green color. Fairy Ring circles may vary in size from one or two feet to 50 feet or more in diameter. Sometimes there will be many mushrooms or toadstools appearing in the area of dead grass. There is no chemical remedy.
If mushrooms or toadstools are a severe annoyance removal and replacement of soil to eliminate the organic source may be necessary. In some cases, like dense shade, site alteration may not be possible and consideration should be given to tolerant ground covers as an alternative to grass.