Just my experience I had similar problems in my yard. this year I did a remodel to the bathroom and found that my bathtub was not connected do to house being jacked up years before and Im thinking maybe to much water causing fungus, just a thought.

Half bury a coffee can in a dying spot. fill with water, wait several minutes, and if it's bugs they'll float up.

The pattern looks like cinch bugs.

its right across from the door... maybe a 2 legged wizzer?

that's where I'd peer off of the walkway if I lived there.

I've thought that too, I've got two boys 2 & 4 it's a possibility.

Looks like somebody dumped something on it.that or its too hot for some reason

Fungus, a lot out here in hood county

Could be fungus. Can you get a close up of the blades?

You have to become a Lawn Detective.