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Common Patch and Ring Lawn Diseases

Summer patch, necrotic ring spot, and brown patch: these grass diseases take no prisoners. Lawn diseases are always in the wings, just waiting for a weak moment to attack your grass. Any time can be a prime time for fungal lawn disease to move in, if your turf is stressed from lack of water, high temperatures, too much moisture or the wrong kind of care. Learn more about how lawn disease develops and tips to prevent it, but first you have to know what to look for. Here are three lawn diseases that you'll notice by their usual circular or ring shapes.

Summer Patch

This fungus usually moves in about mid-summer, when your grass is suffering from heat, drought, and high humidity. Summer patch lawn disease begins with small, scattered light green patches that turn grass reddish-brown, and then light tan. These crescent-shaped patches can come up quickly and completely destroy a lawn. Although the symptoms appear in June or July, the disease actually begins by rotting the roots of your grass in early May.

Necrotic Ring Spot

Necrotic Ring Spot is another serious lawn disease that can destroy a lawn very suddenly. Its patches or rings of dead grass are brought on by dry, followed by wet, weather. Lawns 2 to 8 years old are favorite victims. The disease is most active in spring and fall, but it also shows up in summer during times of water stress. If your lawn has Necrotic Ring Spot, you'll first notice scattered light yellow patches, usually 2 to 6” wide. The disease leaves a ring of dead turf that becomes brown or straw color with a healthy-looking green area in the center. This has prompted the nickname frog-eye disease.

Brown Patch

Brown patch lawn disease usually strikes in the heat of summer, during humid, wet weather, when temperatures stay high even through the night. Brown Patch lawn disease creates irregular, circular areas up to several feet wide. The diseased patches turn purplish-green and then fade to brown. Patches look sunken as the leaves of the grass die and mat down. The edges of these large spots often have a darker, water-soaked appearance.

 Lawn Diseases are Easier to Prevent than to Cure

Here are a few ways we can work together to keep the Ring Gang of lawn diseases out of your lawn:

  • Spring Green’s lawn fertilization program controls unhealthy bursts of turf growth that can attract disease.
  • Regular core aeration helps nutrients and water reach roots and breaks up thatch, which is one place diseases like to breed.
  • Deep, infrequent watering in the early morning, keeps moisture from remaining on the grass surface too long, which attracts disease.
  • Mowing frequently, at a high height and with a sharp mower blade, further helps to keep disease out.
  • Overseeding with disease-resistant grasses is another option you can consider.

If you suspect your lawn has any type of lawn disease, contact your neighborhood Spring Green about treatment services immediately. Quick action can make a big difference to save your lawn. 

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Dollar Spot

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Prevention of Disease

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Brown Patch and Large Patch Lawn Disease