How to Identify 5 Common Lawn Diseases
Lawn diseases can be difficult to identify because they often look similar to other problems, such as poor nutrition or insect damage. However, there are some common symptoms that can help you narrow down the possibilities. If your lawn has brown patches that seem to spread, it could be due to a disease called brown patch.
If circular patches of grass turn yellow or brown and then die, this is likely caused by dollar spot. Red thread produces reddish-brown lesions on the leaves of grass, while snow mold appears as white or grayish-green patches on the ground after snowfall. Finally, rust usually shows up as orange or red spots on the blades of grass.
By knowing what to look for, you can more easily identify which disease is affecting your lawn and take steps to treat it accordingly.
- Look for brown patches in your lawn that are spreading
- Check for areas of your lawn where the grass is thinning out or dying
- Look for any unusual growth patterns, such as long runners or excessive tillering
- Examine the blades of grass for signs of disease, such as rust-colored spots or lesions
- Have a soil test done to check for nutrient deficiencies or imbalances that could be causing problems with your lawn
How to Treat Lawn Disease
Lawn diseases can be frustrating to deal with, but there are some things you can do to help your lawn recover. First, it’s important to identify the type of disease affecting your lawn. Common diseases include brown patch, powdery mildew, and red thread.
Each disease is caused by different fungi and has different symptoms.
Once you’ve identified the disease, you can take steps to treat it. For example, brown patch is best treated with a fungicide that contains the active ingredient chlorothalonil.
Powdery mildew can be treated with horticultural oil or sulfur-based fungicides. Red thread is best controlled with nitrogen-rich fertilizer and regular mowing.
If you’re not sure what type of disease is affecting your lawn, contact a local extension office or certified nursery professional for help.

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How Do I Identify a Grass Disease?
If you’re concerned that your grass may be sick, there are a few things you can look for to identify the problem. First, take note of any changes in color or texture. Yellowing, browning, or wilting leaves could be signs of disease.
You should also look out for any unusual growth patterns, like patches of grass that are taller or shorter than the rest.
Of course, it’s important to remember that not all changes in appearance are indicative of disease. Sometimes, environmental factors like drought or heat stress can cause your grass to change color.
So, if you’re unsure whether what you’re seeing is normal or not, it’s always best to consult with a lawn care professional. They’ll be able to diagnose the problem and recommend the best course of action.
What are Common Lawn Diseases?
There are a few common lawn diseases that can affect your grass, and they include brown patch, dollar spot, and rust. Each of these diseases has different symptoms, so it’s important to be able to identify them in order to properly treat your lawn.
Brown patch is a fungal disease that affects warm-season grasses.
It typically appears as circular patches of brown grass that are 2-8 inches in diameter. The affected areas may also be covered in a thin layer of white fungus. Brown patch is most active during periods of high humidity and temperatures between 80-90 degrees Fahrenheit.
Treatment for this disease includes removing infected leaves, applying fungicide, and increasing air circulation around the affected area.
Dollar spot is another fungal disease that primarily affects cool-season grasses. It appears as small (1-2 inch), round patches of brown or tan grass with yellowish margins.
Dollar spot is most active during periods of high humidity and temperatures between 60-80 degrees Fahrenheit. Treatment includes removing infected leaves, applying fungicide, and increasing air circulation around the affected area.
Rust is a fungal disease that can affect both cool-season and warm- season grasses.
It appears as small (1-2 mm), orange or reddish pustules on the blades of grass. Rust is most active during periods of high humidity and temperatures between 60-80 degrees Fahrenheit.
What Does Turf Disease Look Like?
If you notice patches of brown or yellow grass in your lawn, it could be a sign of turf disease. Other symptoms may include thinning grass, bare spots, and discolored leaves. If you think your lawn has a turf disease, it’s important to have it diagnosed by a professional so that you can get the proper treatment.
How Do I Identify And Treat Lawn Fungus?
Lawn fungus can be difficult to identify and treat. There are many different types of lawn fungus, and each type has its own unique set of symptoms. Some common symptoms of lawn fungus include discoloration, patches of dead grass, and mushrooms growing in the lawn.
To identify the type of lawn fungus you have, it is important to take a sample of the affected grass to your local nursery or cooperative extension office. They will be able to examine the sample under a microscope and tell you which type of fungi is present. Once you know the type of fungi, you can select the appropriate treatment.
Some common treatments for lawn fungi include fungicides, cultural practices, and biological controls. Fungicides are chemicals that kill fungi. They are available in both liquid and granular form, and they can be applied either with a sprayer or spreader.
Cultural practices such as Proper mowing height (3 inches), watering deeply but infrequently (1-2 inches per week), aerating compacted soils, and dethatching can help prevent fungal growth. Biological controls use living organisms to control Lawn Fungus populations. Commonly used biological controls include Trichoderma species (fungus) and Bacillus subtilis (bacteria).
Identifying Common Diseases in Your Lawn
Conclusion
If your lawn is looking a little worse for wear, it may be suffering from one of these five common diseases. Here’s how to identify them and what you can do to treat them.
Powdery mildew is one of the most common lawn diseases.
It looks like a white or gray powder on the leaves of your grass and can spread quickly if not treated. To get rid of powdery mildew, use a fungicide specifically designed for this disease.
Another common lawn disease is brown patch.
Brown patch appears as large, brown patches in your grass and is caused by a fungus that thrives in warm, wet weather. The best way to treat brown patch is to water your lawn less frequently and mow at a higher setting. If the problem persists, you may need to use a fungicide.
Rust is another fungal disease that affects lawns. It appears as red, orange, or brown spots on the leaves of your grass and can spread quickly if not treated properly. To get rid of rust, use a fungicide designed specifically for this disease.
You may also need to increase the amount of nitrogen in your soil to prevent future outbreaks.
Leaf spot is another common lawn disease that causes small spots on the leaves of your grass. These spots can eventually turn yellow or brown and may cause the leaves to fall off prematurely.
To treat leaf spot, use a fungicide designed specifically for this disease. You should also rake up any fallen leaves to prevent the fungus from spreading further.