Brown patch fungus is caused byRhizoctonia solani.
The fungus often appears in mid to late summer in hot and humid weather.
Rhizoctoniacan affect any cool-seasonlawn grassbut is especially harmful to ryegrass andtall fescue.
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Kentucky bluegrass and fine fescues can occasionally be affected, but the damage is usually minimal.
Brown patch fungus can affect warm-season grasses, including St. Augustine grass and zoysiagrass.
Its also easy to spread fungus via foot traffic andgrass clippings, so immediate treatment is important.
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Begin brown patch control in the spring with aeration and dethatching.
Apply fungicide when the fungal patches appear (usually mid to late summer).
Reseed with different grass species by over-seeding over several fall seasons.
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For quicker results, eliminate the old turf grasses in spring and reseed them immediately.
TheRhizoctoniafungus may be present in the soil for some time before it manifests as brown patch disease.
Periods of rainy weather when the air is saturated with moisture may also prompt the disease to emerge.
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Warning
Fungicide powders and sprays are typically less toxic to pets and humans than herbicides and pesticides.
Still, some are known to irritate the eyes or throat.
More severe health problems are possible for individuals who repeatedly use fungicides or have high exposure.
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you could stop work when the efforts show results.
Always give a shot to control brown patch fungus by adjusting cultural practices before reaching for chemical fungicides.
They will be the most visible in the morning.
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This reduces the humidity that favors the fungus.
The best way to do this is to aerate and dethatch the lawn annually.
Aeration is usually done with a power rental tool or a hired professional lawn service.
Avoid feeding your lawn during hot and humid weather, and reduce the fertilizer used.
Watering is probably unnecessary if you are getting 1 inch of rainfall per week.
If dew is collecting on your lawn each morning, your lawn probably does not need to be irrigated.
Spray the first treatment immediately after the symptoms, especially if hot and humid weather is expected.
As with any chemical program, spot-treat diseased areas first rather than apply chemicals broadly over the entire lawn.
A variety of grasses are available with moderate resistance to theRhizoctoniafungus.
If a brown patch is an annual occurrence, consider top-seeding your lawn with resistant grasses.
Check with your local university extension service for recommendations for resistant grass species.
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Tip
The best way to prevent brown patch fungus is to keep your grass healthy.
Remove the dead layer, treat the cause of the brown patch, and reseed if necessary.
Grass can recover from brown patches, but it can take some time.
Reapply this spray every three days.
Do not add a lot of baking soda since it can raise the soil’s alkalinity.
Another solution is to spray neem oil on the spot, repeating as necessary until it disappears.
Brown Patch, Yellow Patch, and other Rhizoctonia Leaf and Sheath Spot Diseases of Turfgrass.
University of Massachusetts Amherst Extension.
Potential health effects of pesticides.
Pennsylvania State University Extension.
