We have had ton's of rain here in Kansas,but I have lived in this house since 1989 and I have never seen these brownish,yellowish,grey colored spots in my yard! I have tall Fescue and was in really good shape till now ,,Any idea's out there ?
It seems like a soil-inhabiting fungi of the Basidiomycetes group, like the ones responsible of "fairy-rings", but I may be wrong. Anyway, it is not recommended nor effective to change soil pH or apply fungicides; your best bet may be a soil fumigant but use exteme care or hire a professional applicator. Hope this helps
Have you looked for grubs--I had a terrible infestation of grubs and my grass was literally eaten away. I used nematodes and now I have thick grass where I had none!!