Midwest Garden Guys

MIKE: Scott, I’m noticing a few lawn issues already, and the one I’ve seen the most of this year is browning out, but not the usual grub patterns.
SCOTT: Is the damage possibly similar to the Fall Army Worm invasion we had a couple years back? Massive sections gone?
MIKE: You got it, Scott. What a coincidence … setting me up like a volleyball player! I received some photos from a friend in Northwest Ohio. Their photos looked like a totally devastated lawn. This friend told me that their lawn looked absolutely gorgeous after their final mowing last fall. I asked if it would be alright to come check things out.
SCOTT: So, what did you find?
MIKE: Upon pulling into this friend’s driveway, I noticed identical lawn damage to the lawns I saw throughout the neighborhood. Then, while exploring their property, carving out multiple four-inch squares in both shady and sunny areas, I discovered that the sunny areas had a buildup of thatch, while the shade cores had none.
SCOTT: The definition of thatch in lawns is, “A buildup of organic matter that exists between the soil and grass.” Mostly dead grass cuttings.
MIKE: Exactly… now mind you, there was a dense root system in each of the sections I cut up. At the same time, the top growth had been sheared off. This eliminated any discussion about grub activity as grubs eat the roots of the lawn, not the blades on top. 
My friend did tell me that while mowing in mid-August, September, and first of October they noticed hundreds of tiny creamy moths flying around at soil level. My immediate reaction was Wow! That helped eliminate any Chinch bug activity.
SCOTT: And Chinch bugs are…?
MIKE: Chinch bugs are tiny, usually black and white, lawn damaging insects that suck the chlorophyll from grass plants, while at the same time injecting a toxin in the grass blades, killing the grasses. 
In this case, the squares I cut up showed signs of being cropped at ground level. Hmmm…? Hundreds of moths, dense root system and dead grass blades cut at ground level. This sounds like the Fall Army Worm we had blown into the midwest by a hurricane a couple of years ago. However, the likelihood of having the Fall Army Worm problem we had before is slim. These insects are much more noticeable in the southern regions of the USA. So, the only other two cutting insects in the midwest are either Cut Worm or Sod Webworm.
With the clues of a heavy thatch layer, dense root base and grass blades cut at ground level, I concluded that tearing out all the dead grass and re-seeding was inevitable no matter which worm caused the brown out.
So, yes Scott, the damage we are noticing in sunny, sandy lawns is almost identical to the Fall Army Worm but caused by either the Sod Webworm or Cut Worm.
Your Midwest Garden Podcast guys, Mike O’Rourke and Scott Sandstrom, will be sharing gardening advice and information with readers throughout the growing season. O’Rourke, retired from Black Diamond Garden Center and known as the Garden Guy for many years, discusses landscape issues with Sandstrom in a casual conversation designed to educate listeners and readers, on a wide variety of topics.