Have you ever heard of grass fungus? It sounds gross, but don’t worry; it won’t harm you or your pets unless you eat it, and we doubt you’re planning on eating your turf any time soon. Lawn fungus is a problem for your grass, though. It affects all types of grass, causing discoloration, and damage, and even killing your lawn if left untreated. Fungus on grass can appear as spots, patches, or discoloration that can worsen without treatment.
At Arbor-Nomics, we understand the different types of grass fungi native to the Georgia area, and we know how to treat them effectively. So how do you know if your grass has a fungus problem? We’ll tell you what to look for, and what to do if you see it in your grass.
Common Types of Grass Fungus in Georgia
The most common types of grass fungus in Georgia are:
- Powdery Mildew (Erysiphe graminis)
Powdery mildew looks like white, gray, or yellow tufts of felty fungus on grass blades. Over time, the grass will start to turn yellow, then tan or brown, and patches may start to die off.
This white grass fungus thrives where the sun can’t reach it, in shady, unventilated parts of the lawn, especially when temperatures are between 60°- 72°F. It grows best on ryegrass, Kentucky bluegrass, fine fescue, bentgrass, and Bermuda grass.
- Brown Patch Fungus (Rhizoctonia solani)
Brown patch fungus looks exactly as it sounds. It starts as small brown spots on the leaf blades and eventually spreads and bleeds together, eventually turning the whole leaf and big, irregular patches of your lawn, brown.
Brown patch fungus survives in lower temperatures but doesn’t start to show until temperatures and humidity rise, making it more noticeable in late spring or early summer. Damp and stagnant environments and fast-release nitrogen fertilizers will encourage this fungus to grow faster.
- Dollar Spot (Clarireedia jacksonii)
Dollar spot fungus causes small, silver-dollar-size brown or straw-colored patches in the grass. Individual leaf blades will show light-colored lesions, while the entire lawn may show sunken, thinner patches.
This fungus thrives on many grasses but tends to affect Bermuda grass the most. It spreads easily, growing from the infected plants, and spreading by wind, human or animal traffic, water, or lawn equipment, and thrives in damp, dense environments with thatching and compacted soil.
- Leaf Spot (Cochliobolus, Magnaporthe, or M. Grisea)
Leaf spot causes oval-shaped spots to appear on grass blades. The spots may be black, brown, or tan, with reddish-colored halos, and they range from the size of a pinhead to large blotches.
Leaf spot occurs due to fungus and bacteria, and is spread by pests, poor drainage, lawn debris, compacted soil, and unclean yard tools. It occurs on any grass varietal but stays only on the leaves without destroying the root system, which makes it easier to treat without harming the surrounding lawn.
- Blight (Pythium blight)
Blight takes many forms, including a slimy brown or white grass fungus that is greasy looking when damp, but yellowish when dry. There are over 20 types of fungus that cause blight and all of them cause the grass to eventually turn brown and die in large patches.
Blight most often happens when you mow the lawn, and then overwater it at night, when the weather is warm and humid. These conditions allow the blight to enter the damaged grass blades and grow. It’s also spread by foot traffic and lawnmower blades, making it difficult to control, even if you’re a homeowner dedicated to lawn care. Removing debris and improving sunlight exposure can help control white grass fungus and protect your yard.
What Causes Fungus in Grass
So what causes fungus in grass? The following are conditions that will promote fungus growth in your lawn.
- Humidity
Humid conditions are the top cause of fungus and mildew growth. The EPA states that any humidity above 60% creates the potential for mold and fungus growth. When the air is damp, then these organisms can flourish, unchecked.
This is especially true in warmer temperatures, which is why grass fungus easily becomes an issue in Georgia, where the coastal areas often have daily humidity up to 80%, and even inland cities like Atlanta and Macon have an average of over 68% year-round. The entire state becomes muggy, and the perfect environment for fungal growth, between May and September.
- Poor drainage
Conditions that don’t allow the soil in your yard to dry out will encourage fungus growth. Poor drainage in your yard means stagnant water accumulating after heavy rainfall, or even regular watering, which will allow fungus to thrive, especially in the warmer months of the year.
- Lack of airflow
When air can’t ventilate the soil properly, either because it’s too compact or because there’s dense grass thatching, fungus has damp places to thrive. Although you’ll likely need an antifungal treatment, airflow and sunlight will dry out the soil, reducing fungal growth.
Factors like high humidity, poor drainage, and compact soil are key contributors to what causes fungus in grass.
Lawn Fungus Treatment
Ready to learn how to treat brown patch fungus, dollar spot, blight, and more? There are a few things you can do on your own before calling for professional help. These include:
- Encouraging more sunlight and airflow on the lawn by pruning shady trees, and clearing leaves and debris regularly
- Mowing the lawn (but not too short)
- Being careful not to overwater the lawn
- Fixing any drainage problems your lawn has, so there’s no chance of stagnant water accumulating in the grass
- Learning more about the type of fungus and how to treat it (for example, rinsing powdery mildew off the grass and removing nearby debris could kill it off)
- Making sure to properly clean any yardwork tools to ensure no fungus spores survive to reinfect the area
- Using a fungicide to kill lawn fungus spores
Some of these lawn care techniques are simple enough for the average homeowner to take care of, but if it’s not working, or if selecting and handling fungicides is uncomfortable for you, call Arbor-Nomics for assistance. A lawn-care professional will be able to help by:
- Treating the fungus with expert care, using the right fungicide for the type of grass your lawn is made of
- Aerating your lawn regularly to encourage proper soil airflow and sun penetration
- Reseeding your lawn after the fungus is cleared up
- Advising you on practical lawn-care tips you can do on your own between visits
Call Arbor-Nomics Today for Lawn Treatment and Care
Lawn fungus is an issue many people in Georgia have to deal with at one point or another. While it’s not an emergency, if you try to ignore it, it’ll just get worse. At Arbor-Nomics, we’re experienced professionals in treating all varieties of fungus while keeping your lawn looking its best. Regular lawn care can help prevent fungus on grass and keep your lawn healthy. We’ll assess the problem, and suggest your best options to restore your lawn to a lush vibrant green carpet.
Our services also include weed treatments, fertilization, aeration, overseeding, pest control, ornamental tree and shrub care, and more. Contact us today to request an estimate.