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Do You Have Brown Spots on Your Lawn?

brown patch disease

There’s a fungus lurking, waiting to destroy your lawn. This fungus is known by many names. Its most obvious one is “Brown Patch Disease,” which is a descriptive name. It’s also known as “Large Patch” or by its scientific name, “Rhizoctonia Blight.”

The most frequent victim of this fungus is the St. Augustine grass that is common in Florida lawns. Unfortunately, Brown Patch Disease can also affect several varieties of warm-season turfgrass.

Unlike other bugs and diseases that thrive in the hot, wet summer months, Brown Patch Disease is more likely to impact your lawn when temperatures drop below 70 degrees. It also needs wet grass to survive, so days without high humidity or rain can interrupt its lifecycle.

Nitrogen-heavy lawns with lots of thatch seem to be at a higher risk of contracting Brown Patch Disease. Avoid using too much nitrogen in your lawn fertilizer. Also, be sure to mow the healthy areas of your lawn first and thoroughly clean the grass clippings after trimming infected areas. This fungus can be spread from one area to another by traveling on the mower blades.

Identifying Brown Patch Disease

The first signals are small circles of yellow grass. Later on, you’ll notice redder, browner, and completely dead areas of grass. Some people notice that there is a green center surrounded by a circle of brown grass.

As the fungus attacks the grass, the base where the stem meets the blade will look wilted. It may give off a nasty odor or show signs of a soft, dark rot. Try pulling up the grass out of the soil. If it comes out too easily, it’s a sign that it’s been severely weakened.

Gray Leaf Spot on Grass

Gray Leaf Spot disease is caused by a fungus and requires special fungicides for treatment. You’re most likely to notice Gray Leaf Spot disease during the wettest months of the year. The rain and high humidity create the perfect environment for this fungus to flourish.

Gray Leaf Spot is a perfect name for this disease because it describes exactly what you should look for. If affected, you’ll notice your blades of grass will have a discoloration of a gray circle, often surrounded by a dark green ring. Usually, the spot is circular or oval. As the fungus spreads through the grass, the entire blade changes color as the spots merge together.

The best way to avoid Gray Leaf Spot disease is to water your lawn at the appropriate time of day. Set your sprinkler system for the early morning, so the grass will dry quickly. Evening waterings often leave the grass wet for too long and invite the fungus to take root.

Most lawns affected by the fungus are those with primarily St. Augustine grass. It’s the most prone to this type of infection. The youngest grass is the most likely to be afflicted. Well-established lawns have more protection from damage.

As with all other lawn problems, it’s essential to water and fertilize in the appropriate amounts to avoid issues with bugs or fungus. If you do have Gray Leaf Spot disease, you’ll need to consult a professional. Fungicides, which are the only way to treat this problem, are difficult to apply properly. Some types are not appropriate for residential use.

If you are infected, it may take a long time for your yard to recover, because during cold weather, your grass naturally isn’t growing as quickly. To stop the fungus in its tracks, you’ll need a fungicide. As mentioned in the previous tip, this job is for professionals only. Fungicide can be dangerous and difficult to apply properly.