Aliens!
A few days ago these mysterious dead spots happened in my building's courtyard.
Closeup on one of the rectangular pieces, now that Madeline is inside.
Closeup on the turn, where it appears to split into two sets of 'tracks' or whatever they are.
They look like something rectangular with weedkiller on it was set down in the grass at regular intervals, and the line of marks turns, seems to split into two, and runs along the building. The manager doesn't remember anyone using anything like that in the last two weeks and is just as mystified. I wonder if there's not a pipe running down there that's suddenly leaking, or one of the other tenants (like the old guy down in the end there) did something and didn't tell her, but the manager didn't know of any. She thinks that without a physical explanation, 'aliens!' is as good an explanation as any. XD XD XD
Madeline's opinion - they're perfectly shaped cat beds for sunning in on REALLY BRIGHT days! XD
--Moony