Common Lawn Diseases in North Carolina

Now is the time of year, when our lawns begin talking to us. Showing us signs if something is wrong. Basically – the lawn wants and needs your help. Perhaps you have a patch of brown, gray, or yellow and it’s shaped like solid circles or outline rings or, is it more like a series of spots or splotches? Whatever the case, chances are its fungi. Be observant and listen to your lawn.

In our state, most lawn diseases are caused by fungi. However, some problems that resemble disease can have the same symptoms – such as wilt, excess salts, soil compaction, and chemical damage. So, it’s very important to identify the real cause and treat it appropriately.

Signs of Lawn Fungus

Fungi are microscopic organisms but, there are points in their lifecycle when they can be viewed with the naked eye. You might see –

• Mycelium – a cottony or spider-web-like mass of fungal growth that certain fungi produce when the turf is wet or humidity is high.
• Spore Masses – fuzzy or jelly-like growths produced on the diseased tissue by certain fungi, again usually when the turf is wet or humidity is high.
• Pustules on Leaves – small, spherical structures produced on the leaf surfaces, that contain fungal spores.
• Blisters on Leaves – raised areas of leaf tissue that change color and then rupture to release powdery masses of fungal spores.
• Fruiting Bodies – structures of various shapes and sizes that release fungal spores. Usually dark in color and embedded in diseased plant tissue. May be found on all above- and below-ground parts of the turf plant.
• Sclerotia – small, round, or threadlike structures produced on the diseased turf or in the thatch layer by certain fungi.
• Puffballs – A spherical spore-producing structure up to 3″ in diameter produced on the turf surface. Similar to a mushroom, but lacking a stem or stalk.
• Mushrooms – Spore-producing structures with a cap and stem produced on the turf surface by Basidiomycete fungi.

Some of the more common forms of turf disease in the Piedmont Triad include the following (all are caused by fungi) –

Brown Patch

Brown Patch is a turf disease caused by the Rhizoctonia fungus and is common in bentgrass, bluegrass, tall fescue, and other cool-season grasses. The lawn disease develops on moist foliage in hot, humid weather with daytime temps above 85°F and nighttime temps above 60°F—typically between May and September. Other factors that favor brown patch are – lack of air movement, cloudy weather, dew, overwatering, excessive nitrogen, and too little potassium & phosphorus. The most common recognizable symptom would be circular patches ranging from 6 inches to several feet in diameter. At first sign, call for a Rescue Fungicide Treatment. Getting on our Preventative Fungicide Program will control this fungus before it breaks out and does severe damage.

Dollar Spot

Dollar Spot is a turf disease caused by the Sclerotinia homoeocarpa fungus that occurs in all turfgrasses. The disease has the appearance of light tan or white small spots about the size of a dollar coin—on turf mowed at heights greater than 0.5”, the spots may expand in size up to 6” or more. Heavy dew and excessive wetness in the spring and fall contribute to its presence. Short, fuzzy white mycelium is often observed in the morning when dew is present. At first sign, call for a Rescue Fungicide Treatment. Getting on our Preventative Fungicide Program will control this fungus before it breaks out and does severe damage.

Fairy Ring

Fairy Rings are caused by Basidiomycete fungi that live underground seasonally and show up on turf as dark green circles that may be accompanied by mushrooms—this turf disease can affect all types of turfgrass. Growth of these fungi in the soil can indirectly affect, or even kill, the turfgrass above. Decaying organic matter such as old stumps or dead roots are areas where this will form. Over-irrigation and poor drainage encourage this fungus.

Don’t be fooled by folklore—these rings weren’t made by dancing of fairies and they don’t bring good fortune. Control methods are cost-prohibitive. Removal of Organic matter will help symptoms.

Gray Leaf Spot

Gray Leaf Spot is a lawn disease caused by Pyricularia grisea fungus that occurs in ryegrass and tall fescue infecting and killing the leaf blades. Small, gray lesions appear on leaves in warm, humid weather. The lesions widen and become round or oval spots with a tan center and purplish margin.

Pink Snow Mold

Pink Snow Mold is a turf disease caused by Microdochium fungus that occurs in bentgrass, ryegrass, bluegrass, and tall fescue. It develops during periods of snow and exhibits symptoms as the snow melts. It also can infect turfgrass without snow during periods of cool, wet weather. Then, it’s called Microdochium Patch. Both appear as white or light tan circular patches from 2” to 1’ with a pinkish ring or growth present.

Spring Dead Spot

Spring Dead Spot is a lawn disease caused by Ophiosphaerella fungi that occur in bermudagrass and zoysiagrass. Circular patches from 6” to several feet remain dormant as the turf greens up in the spring then eventually dies and collapses to the soil surface. The patches recur in the same place each year, increasing in size each season.

Call The Lawn Care Professionals

This is only a sampling of the fungal diseases that can impact your lawn. As mentioned earlier, it’s very important to identify the real cause of the problem and treat it appropriately. Doing nothing or, choosing the wrong course of action could exasperate the problem. But it's important to also keep in mind that other things can cause brown spots in your lawn.

If you suspect that you have a turfgrass disease or need help diagnosing why your turf is turning brown, please contact our office immediately so we may come and accurately diagnose the problem. Learn more about our lawn disease treatment program.