I have spreading bald spots in my yard (Western PA.) It started as 2 spots that I noticed and thought might have been caused by my two small dogs in the early spring. However, the spots are expanding and trails can be found linking them – there’s now about 7 spots between 5 and 10 inches in diameter. The links between them aren’t obvious until you run your finger between them, the trails are 1-2 inches wide and between 6 and 12 inches long. There are a number of holes from some pest with small mounds at some of them. I have found small yellow-red ants and earwigs in and around the spots. Digging up the spots I have found small (tiny) white (aphids?) bugs and very thin (hairlike) white worms. I’m not sure if the ants are nesting or not but they do nest a short distance away under foot long landscaping rocks. I know most of the spots are not from my dogs, but they could have caused a fungal infection? Are the pests (ants, earwigs, worms) doing damage and should I just replant?
My yard gets little sun, a few hours a day… and because of the local surroundings it is perpetually damp. I have yet to mow the grass and have dry clippings – but the problem has only begun this year.
I do have at least one mole which I have seen, but she tends to go in my neighbor’s garden from what I can tell. There are no molehills in my yard and the trails are trails of bald spots which some grass still covers from either side. The holes are 1/4″ and 1/16″ wide and I’m positive there are insects and worms but I’m not sure whether they are doing the damage or just noticeable because of the damage. I have dug up some of the area and unless the mole tunnels are more than a shovel length down that isn’t the problem – but I will look into it.
I am now fairly certain the problem is an unidentified aphid farming ant colony. I think they are yellow meadow ants (Lasius flavus) because I recently overturned a rock and found them more concerned with moving aphids underground than anything else. Pulling up a thick grass stalk revealed 1/2″ think aphid ring around the base just below dirt level.