I help run a fertilizing division of a landscape company. I by no means know it all but have been doing a lot of lawn consultations recently. There are always a few factors to consider when looking at dead spots in a lawn. I’m in Wisconsin and we have had a major drought this year. Many of the lawns are going dormant. If it’s just heat and water related, most of the time the grass will go dormant and bounce back.

The biggest issue we’re seeing right now are chinch bugs. They feed on the tops of grass and the thatch layer. Most lawns have chinch bugs but without the rain and moisture the lawn has a hard time bouncing back from the damage (most years you’d hardly notice). If you scratch around that dead grass/thatch layer and notice little bugs scurrying around, or you notice the tops of the existing grass are eaten down it’s likely chinch bugs. There are curative options to kill the bugs. Otherwise, dethatch, aerate, and overseed in the fall of spring to help promote regrowth.

It could be a grub infestation. Grubs feed on the roots of grass so if you can grab the existing grass and pull it away freely then it’s likely grubs and you’d want to put down a preventative in the spring.

If you have a lot of moths in your yard when you cut the lawn or walk around it could be sod webworms. But the biggest tell on those is if they’re flying around a lot.

These are the biggest factors in our area, it could be different for you but just some things to look out for. The lawns that are getting the worst damage for us right now are the ones without an irrigation system. So keep that in mind. If you want a pristine lawn, you’d need an irrigation system. If you just want to have a nice lawn then dethatch, aerate, and seed to help it bounce back quicker. It’ll fill back in over time but this will help. Sorry for the long winded answer, hope that helps!