All disease can be attributed to a deficiency in your lawn’s ecosystem. The best preventative is proper lawn care. Be certain to monitor your lawn each week in order to diagnose and treat disease in the early stages. Aerate and top-dress with a disease-resistant ryegrass.
Brown patch is a fungus that thrives in humid, shaded areas, heavy thatch and areas with high nitrogen levels. This disease appears in crescent-shaped or round brown patches. Aerate, moderate nitrogen levels, de-thatch and prune shrubs and shade trees. If you have dead patches, re-seed with endophytic rye grass.
Dollar spot is a fungus that thrives on lawns that have too little nitrogen and too much moisture above the soil. These are both products of that build-up and improper watering. This disease appears in spring or fall as circular bleached dead spots. To avoid dollar spot, de-thatch, aerate and test nitrogen levels in fall. Amend with a slow releasing organic product. Water in early morning and roll your lawn to level out uneven areas where rain water pools. Dollar spot thrives on grass that is cut too short and too often. Once you take measures, the problem will subside.
Mildew appears as a gray, white powdery or cobwebby growth. It usually appears on the upper surface of grass blades. This fungus is more severe in wet, shaded areas that have poor air circulation. To correct this problem, prune shade trees, aerate and never water in the evening. Fertilize your lawn and mow your grass high with very sharp blades.
Toadstools often appear in lawns during wet spells in summer. They are an above-ground growth of a fungus that is growing on underground organic matter – for example, a buried root or stump. Toadstools are the result of excessive shade and poor drainage. These can be removed easily by raking. They are harmless and there is no other method of killing them without damaging your lawn. They thrive on calcium deficient and slightly acidic soil. Be sure to test your calcium content and pH balance. Add wood ashes and dolomitic limestone to bring your pH up to 6.5.