Lawn Fungus Symptoms and Appearance
Maintaining a healthy and well-tended lawn is the best way to prevent fungal infections from damaging the appearance of your grass. If your lawn doesn't get adequate water and fertilizer or if you mow it incorrectly, infection can begin and spread throughout the grass. Knowing the symptoms and appearance of a lawn infected with fungi will help you take immediate steps to remedy the situation and maintain the health and attractiveness of your grass.
A healthy lawn can withstand the presence of fungi without being vulnerable to damage. For a fungal disease to occur, your lawn is lacking an important component of good health. Grass is more susceptible to fungal infections if it doesn't receive adequate water regularly. A lawn that is not fertilized regularly also faces an increased risk of a fungal infection. In addition, extreme temperatures can increase the risk of fungi damage to your lawn.
When a fungal infection is present, you will notice the blades of grass suffering damage. Brown or purple stripes often appear on the individual blades of grass when your lawn is infected with a fungus called Bipolaris sorokiniana. Blades of grass that look like they have a layer of dust or white chalk on them is a symptom of powdery mildew caused by the fungus Erysiphe graminis. And Ustilago striiformis, or stripe smut, causes the blades of grass to turn black and split.
Other types of fungi can cause distinctive patterns of damage throughout your lawn. Magnaporthe poae causes summer patch, which leaves circles of yellow throughout your lawn. The fungus Rhizoctonia cerealis causes yellow patch, which leaves smaller circles of yellow. Fairy ring, caused by numerous different fungi, leaves a dark green section of grass surrounded by a ring of brown or dying grass. Microdochium patch, caused by the Microdochium nivale fungus, leaves pink circular patches in your lawn. Spring dead spot, Rhizoctonia large patch and Pythium blight also cause circular patches of brown or yellow grass.
Treatment and Prevention
Fungicides are often an effective way to treat a fungal disease and restore the health and appearance of your lawn. Changing your care techniques to support the growing requirements of grass might also help your lawn recover while reducing your risk of future fungi problems. Water your grass regularly, but don't water it too much because waterlogged grass invites fungi. Very dry grass also makes your lawn more susceptible. A nitrogen-based fertilizer applied annually supplies your grass with the nutrients it needs to thrive, which reduces the risk of fungal infections. When you mow, don't remove more than one-third of the length of the blades of grass at a time. This will help maintain healthy blades and reduce the risk of fungal infections.
Sara Ipatenco has taught writing, health and nutrition. She started writing in 2007 and has been published in Teaching Tolerance magazine. Ipatenco holds a bachelor's degree and a master's degree in education, both from the University of Denver.