The healthiness of living things, at times, can be paramount. We spend a good portion of our lives either trying to remain healthy or fighting to become healthy again. We also worry about the health of those around us; our family, friends, neighbors and even, if applicable, our pets. As trivial as it seems, by comparison, we also want our lawn, flowers, shrubs and trees to remain healthy. This year unfortunately for many, our lawns are suffering from diseases. The symptoms of these diseases have become increasingly obvious over the past 4-5 weeks. This column focuses on identifying turf diseases as well as possible causes and treatments.
Dollar Spot (Clarireedia jacksonii) Dollar Spot is aptly named because the initial symptom is small brown patches in the lawn that are the size of a silver dollar. Dollar Spot can result of too much moisture and not enough fertilizer in the lawn. Reducing excess moisture on the lawn, if possible, through the adjustment of an irrigation system or your downspouts will help to reduce the likelihood of this disease occurring. Regular fertilization also helps your lawn to remain healthy and less likely to be affected by Dollar Spot. Pruning overgrown vegetation also increases the air flow in the lawn area. Azoxystrobin and propiconazole are two ingredients that can be used to affectively treat this disease.
Summer Patch (Magnaporthiopsis poae) This disease creates areas of straw-colored grass in various shapes and sizes. High temperatures and high humidity, both prevalent this summer, promotes its development during late May through late September. Preventative measures involve watering the lawns infrequently but deeply and mowing at a height of between 2 1/5-3”. Core aerating also helps improve the air circulation around the root system of grass and reduced the chance of Summer Patch occurring. If Summer Patch is already present, applying lime to the soil can slow the progression.
Brown Patch (Rhizoctonia solani) This disease causes patches of yellow and brown grass that occur in a circular pattern. The perimeter of the circular area is a bit darker in color. Damp humid conditions coupled with unseasonable warm weather in the spring lead to Brown Patch occurrence. Core aeration in the fall helps to prevent Brown Patch. Azoxystrobin and fluoxastrin are two active ingredients in fungicides that work well against Brown Patch.
Rust (Puccinia) Infected blades of grass have orange spots on them. These orange spores often spread to shoes or clothes. Under fertilizing, too much moisture and excessive shade can cause the rust to develop and spread. The elimination of excessive watering in shaded areas will help prevent rest. If a lawn already has rust applying a high nitrogen fertilizer will often help to eliminate it.
Red Thread (Laetisaria fuciformis) Infected lawns develop red strands of thinning grass. Red thread typically develops early in the spring during periods of high humidity and cool temperatures. Regular fertilization develops a healthy lawn which can be resistant to Red Thread. Although Red Thread doesn’t kill the lawn, prevention is the best treatment.
Snow Mold (Typhula or Monographella) Matted patches of stiff lawn is the tell-tale sign of Snow Molds. Although there are many types, Pink and Gray Snow mold are the most common. This fungus develops, as the name indicates during the winter when there are large amounts of snow sitting on top of the lawn. Too much fertilizer applied in the fall can be a contributing factor. Unfortunately, no fungicides are effective against snow molds. The only way to treat it is to try to prevent it. Raking and removing the leaves in the fall, expose your lawn, when possible, to sunlight through pruning and make sure not to over fertilize especially in the fall.
Powdery Mildew (Blumeria graminis) although more common on shrubs, powdery mildew can also affect grass. Blades become infected with a thick white substance. Shaded lawns tend to be more at risk for this disease. Potassium bicarbonate and lime are both very effective treatments.
Wishing you and your lawn a most healthy summer. “Every blade of grass had its angel that bends over it and whispers “Grow! Grow!” from the Talmud.
Kathleen Carr is the owner of The Growing Scene, Inc.,a landscaping company. She can be reached by calling 815-923-7322 or emailing her at Kathleen@thegrowingscene.com. Have a gardening question? Please contact her. She may address it in an upcoming column.
