Generally, consistent good lawn maintenance should keep a lawn disease-free.
Here’s what to look for and potential diseases to investigate further.
A home lawn rarely needs fungicide system as a preventative measure or treatment.
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Try fixing conditions first.
Brown patch also involves a variety of warm-season grasses, includingSt.
Powdery Mildew
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Powdery mildewis a fungal disease common to many plants.
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It looks like white dust sprinkled all over the leaf blades.
Powdery mildew on lawns is most common on cool-season grasses, specifically Kentucky bluegrass.
Cool-season grasses like red fescue, ryegrass, Kentucky bluegrass, and bentgrass are most susceptible.
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Gray snow mold looks like gray circular spots on the grass that affect the leaf tissue.
It mainly affects cold-season grasses, such as bentgrass, annual bluegrass, and perennial ryegrass.
It can affect fine fescue and Kentucky bluegrass, but not as frequently.
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It affects cool-season grasses, mainly creeping bentgrass, perennial ryegrass, Kentucky bluegrass, and annual bluegrass.
This pink-hued disease most often occurs on golf courses with snow cover.
It can cause more severe injury than gray snow mold, which only infects the leaf tissue.
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They can be incomplete or complete circles and grow over 30 feet in diameter.
Dollar spot primarily affects creeping bentgrass, annual bluegrass, Kentucky bluegrass, ryegrass, andBermudagrass.
Kentucky bluegrass seems the most prone to this disease, with larger patches that spread quickly.
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The upper parts of the leaves slowly die, turning to hay.
Leaf Spot
Leaf spot is commonly grouped with melting-out diseases since they usually strike together.
It is a different disease than gray leaf spot.
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It can eventually cause the leaf to turn yellow, tan, or brown.
Melting-Out Disease
Leaf spot and melting-out disease go hand in hand.
In melting-out disease, the fungus progresses to the crowns and roots of the leaves.
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It causes brown or black rotting of tissues and severe thinning of turf.
During summer, leaf spot and melting-out disease can affect nearly every cool-season grass species.
Leaf Blight
Ascochyta leaf blight is a minor lawn disease that usually resolves itself within three weeks.
It mainly affects cool-season grasses like Kentucky bluegrass, perennial ryegrass, and tall fescue.
Grass species that resist this disease include creeping bentgrass, perennial ryegrass, and tall fescue.
The spots can eventually spread and outstretch the entire lawn.
This disease makes affected crowns and roots appear brown or black under a microscope.
It resembles irregular yellow or white patches or rings up to 3 feet wide.
It primarily affects Kentucky bluegrass, red fescue, bentgrass, and annual bluegrass.
It is sometimes confused with summer patch, but it usually has smaller, more numerous doughnut-looking patterns.
Fusarium blight also presents similarly but is an infection caused byFusariumspp.
Pythium Blight
Pythium blight is a warm-weather disease of cold-season grasses, mainly perennial ryegrass.
It can also affect creeping bentgrass, annual bluegrass, and rough bluegrass.
It can cause the die-off of large areas of grass seemingly overnight.
Slime Mold
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Slime mold is technically not a fungus or a disease.
It’s a harmless single-celled organism that looks like slimy, oddly-shaped, 4- to 8-inch patches.
Slime mold can affect all grass species.
Tip
Slime mold may be unsightly, but it can be good for your lawn.
It eats plant pathogens and bacteria.
It primarily affects bentgrasses and bluegrasses.
If you have a known lawn fungal issue, bag the clippings and do not compost them.
Ascochtya leaf blight of turf.
Colorado State University Extension.
Turfgrass Diseases: Summer patch (Causal fungus: Magnaporthiopsis poae).
Turfgrass Diseases: Rust Diseases (Causal fungi: Puccinia spp.).
Michigan State University Extension.
Turfgrass Diseases: Slime Molds.
