Those brown areas in your lawn could be caused by a lawn disease (fungus), lawn insects, or hot dry weather. So how do you figure out if a lawn disease is the problem?
Experts look for brown, black, white or reddish spots on the individual grass blades or circular brown patches of grass where the fungus has spread from the center. Sometimes lawn fungus problems show up in the same area each year.
There are a range of lawn diseases that show up with warm, humid weather. These fungus problems are especially active when your night temperatures and humidity do not drop very much from the levels you are experiencing during daytime hours. You can help your situation by not watering your lawn in the evening as this helps to hold humidity at high levels next to your grass plants for an extended period of time. Experts will always suggest that if you have to water, it is best to irrigate in the morning. Lawns located where air movement is restricted by a fence or hedge generally experience more lawn disease problems as compared to more open areas.
You can help strengthen your grass by not under or over-feeding and by mowing at a taller height. You can also help strengthen your lawn with the newer grass varieties. Many of the grass seed varieties that are available in the top-of-the line seed blends today, like the Scotts Turf Builder Grass Seed line, have improved resistance to lawn fungus disease built right in compared to the older grass varieties.
Use the photos and descriptions below tell if you have some of the more common lawn disease problems in your lawn.
If you need to protect your grass from lawn fungus, Scotts Lawn Fungus Control is a good “systemic” cure, which means the active ingredient is absorbed into your grass plants to protect them from the inside. (Other “contact” controls are not as effective because they must stay on the grass blade leaf surface which means you need to spray frequently as you mow).
Brown Patch on Tall Fescue – Circular patches of dead grass are a symptom of several lawn fungus problems such as Brown Patch and Summer Patch show up during periods of warm temperatures and high humidity. Click photo to enlarge
Dollar Spot on Kentucky Bluegrass – Individual grass blades have white blotches edged in reddish brown the shape of an hour glass. Other lawn diseases that show spots on grass blades are Rust and Helminthosporium Leaf Spot. Click photo to enlarge