10 Lawn Diseases Damaging Your Yard | Killingsworth
  1. 10 Lawn Diseases That Could Be Damaging Your Yard

FEBRUARY 01 2022 /

10 Lawn Diseases That Could Be Damaging Your Yard

Have You Noticed Any of These Lawn Diseases In Your Yard?

Without specific professional care, your lawn may fall victim to disease. While some lawn diseases are more common than others, and depend on your grass type, your yard remains vulnerable to a multitude of diseases.  Below, we cover the 10 lawn diseases that may be threatening your lawn. But we don’t stop there! You won’t only learn what these diseases are, but also how to treat (and prevent) them, allowing you to restore health to your lawn.  With our expert help, you’ll rest assured that your lawn is safe from damaging diseases. Let’s get started!

10 Lawn Diseases To Be Aware Of

1) Brown Patch

Brown patches typically affect lawns during the summer. These patches often resemble dry or dead grass, and may appear to be a darker color on the outer ring.  This fungal disease can be found in all cool-season turfgrasses throughout the United States. It usually appears on lawns in areas of high humidity, or lawns that experience prolonged wetness. However, it is most common in Tall Fescue, Perennial Ryegrass, Kentucky Bluegrass, Bentgrass and St. Augustinegrass. 

2) Leaf Spot and Melting-Out

These lawn diseases are caused by a group of fungi. While these are two different diseases, they have similar characteristics and symptoms. The main difference is that leaf spot is active in hot, humid climates, and melting-out occurs in cool, wet environments. Leaf spot causes dark brown spots to appear on grass blades, and is usually contained to a smaller area of your lawn. Melting-out, however, can affect a large area of your yard, causing thinning out or death of the grass. 

3) Dollar Spot

If you’re noticing small, silver dollar-sized spots of straw-colored grass in your lawn, chances are it’s dollar spot. Dollar spot is a fungal disease that affects leaf tissue, but does not reach the roots and crowns of turfgrass. This lawn disease is most active in warm temperatures with high humidity, and affects both warm- and cool-season grasses. The worst part? How you care for your lawn may be what’s causing dollar spot. Mowing too closely, lack of fertilizer and persistently wet grass may be the root of the problem (no pun intended). However, this is usually an easy fix! Adjusting your mowing height, fertilizing your lawn throughout the year and keeping excess moisture off of your grass may help prevent dollar spot from affecting your yard. But if that doesn’t work, your best bet is always to contact your local lawn care professional

4) Microdochium Patch

Also known as Pink Snow Mold, this white-pink lawn disease is typically found on Bentgrass, Bermudagrass and Kentucky Bluegrass.  Pink Snow Mold is common on lawns in cool, wet environments, especially if snow is present. However, snow is not necessary to cause infection (see #7). Factors such as cold, fog, and light rain are the most opportune environments for this disease to spread. The good news, though, is that Pink Snow Mold only affects the grass blades, not the crown or root. 

5) Fairy Ring

Contrary to old folk tales, fairy rings are not the result of fairies dancing on your lawn. This lawn disease is actually caused by more than 40 types of fungi, and can affect all species of turf grass in the United States. Fairy rings typically cause damage between early spring and early winter. At first, you may spot an area of dark, lush grass. Before too long, you’ll likely notice a ring of mushrooms appear. If left untreated, this unsightly ring can cause serious damage to your lawn. The fungus produced by this disease prevents water and nutrients from reaching the grass roots, eventually causing the roots to dry out and die. 

6) Necrotic Ring Spot

You may know Necrotic Ring Spot by another name, Fusarium Blight. No matter what you call it, this soil-borne fungal lawn disease can cause some issues for your yard.  The cause of Necrotic Ring Spot? Overwatering. Lawns that receive entirely too much water are likely to fall victim to this lawn disease. Lawns with Necrotic Ring Spot will usually have sunken straw-colored or gray patches of grass, approximately four to 16 inches in diameter. 

7) Fusarium Patch

This disease is the same as Microdochium Patch (see #4), but it is referred to Fusarium Patch when it occurs in the absence of snow. It thrives in wet conditions with temperatures below 60 degrees Fahrenheit. This type of lawn disease is especially threatening to golf courses, not only for its unattractive appearance, but also for causing putting difficulties.  Fun Fact: Golfers are likely to notice many of the lawn diseases on this list. Since most of these diseases affect turfgrasses, golf courses and putting greens are vulnerable to disease. So the next time you’re lining up a putt and notice what seems to be a dead patch of grass complicating your shot, chances are it’s one of the diseases on this list!

8) Powdery Mildew

This fungal disease can affect more than just your lawn—it can spread to your plants as well. Powdery Mildew thrives in warm, dry climates, unlike the other diseases we have listed. However, it requires relatively high humidity to spread.  Powdery Mildew is spread by the air through spores, allowing it to spread throughout your lawn and garden. If your lawn or plants look like they have been dusted with flour, it’s likely Powdery Mildew. When left untreated, this fungus can threaten the health of your lawn and plants, and even kill plants if the infection is severe enough. 

9) Gray Snow Mold

Like it’s displayed in the name, this is a true snow disease. It requires at least eight weeks worth of snow coverage in order to develop in lawns. This typical disease can kill large areas of grass at once, resulting in extremely slow recovery.  Lucky for us in the Carolinas, we aren’t likely to experience Gray Snow Mold. Our friends in the Northern parts of the country may not be as lucky, though. 

10) Pythium Blight

This specific lawn disease thrives in hot, humid weather and spreads rapidly, killing leaves, crowns and plants. It especially affects Creeping Bentgrass, Annual Bluegrass, Rough Bluegrass and Perennial Ryegrass. Pythium Blight looks different depending on what grass type you have. In cool-season grasses, Pythium Blight first appears as small, sunken, circular patches of grass. In warm-season grasses, it starts out as small black or purple spots that can expand into larger areas over time. With favorable conditions, this disease can cause widespread damage and detrimentally harm your lawn. 

How To Protect Your Lawn From Disease

So what can you do to protect your lawn and prevent future lawn diseases from spreading? Seek out professional lawn disease prevention.  Here at Killingsworth, we developed lawn disease prevention into our Premium Lawn Care Package. We understand the threat these lawn diseases pose to your yard, and want to do our part in protecting your lawn.  When you take part in our Premium Lawn Care Package, your yard will receive lawn disease prevention all throughout the summer. The heat of summer is what many of these diseases rely on to spread, which is why we strategically treat and prevent against these diseases in May, June, July and August.  DIY and over-the-counter treatments aren’t enough to treat your lawn against disease. Schedule a service with your friends at Killingsworth to help protect your yard all throughout the year from harmful lawn diseases! 


Content was originally published on June 4, 2015. Content was refreshed on August 5, 2019.