The grass is going to grow like crazy in the early spring regardless of whether you fertilize. Professional grass farmers use their spring application of fertilizer to carry the grass from the time after that initial flush of growth into the summer. In other words they apply after the grass growth slows down. Hence the Memorial Day suggestion by tiemco. Seeding in the spring is not helping matters. You are probably going to water much more frequently to get that seed to sprout. If you would get all your 'densifying' done in the fall, you would be in better shape in the spring. Is your lawn all fescue with no Kentucky bluegrass? KBG would not work much in the shade.

Thanks for the feedback. The grass was a mix of fescue, bluegrass and ryegrass. I wish I could upload a picture so you could see it. Is there a way you can on this forum that I'm not seeing? As for a recovery plan...what would that be? Would I need to completely tear out the old grass and start over or could I simply aerate and over-seed. Also specifically when should I do this? I'm thinking late August to mid-September? As for shade, my lawn is partially shaded, we live in an area with large old oak and maple trees. Thanks for your help.

Get some Tenacity and spray that (follow directions carefully) at seed down and 30 days later. At 60 days later you can use a normal pre-emergent. If you can't find Tenacity locally, it can be ordered through Amazon and other places. That will help prevent next year's crop of poa annua (and other winter weeds).

For all y'all with a fear of chemicals, I would encourage you to use ordinary corn meal or cracked corn to fight off existing fungal diseases and to prevent new outbreaks. Corn meal is a biological approach that will cause no problems for you or your soil. If it does not work for you, please report that back here. In the past, and apparently before j4c11 got here, there were reports of corn meal being the thing that cleared up their disease. And yes, there were some who used it and it did not work. Unfortunately there were a lot of people who never used it but were very vocal/wordy about corn meal being a hoax. Since it had worked for me every year for several years, they were essentially calling me out. Also unfortunately I was not taking good notes to see if there were patterns to the good and bad reports. So I will tell you that it works for most diseases in St Augustine in the south. It has worked in Texas and in Florida - that much I remember. Whether it works in the transition zone or north or on fescue or KBG, I'm less certain. The application rate is 20 pounds per 1,000 square feet. After 3 weeks you should see new grass coming in and not getting the lesions. I know 3 weeks is a lifetime in fungus years, so do what you have to do. If it doesn't seem to be working, you can apply again. Maybe you could use a fungicide in part of the yard and corn meal in part of the yard. If you treat with corn meal, treat the entire yard. If you don't you may miss parts where the disease has not manifested itself yet, but for sure you will get dark green spots where the corn meal has had a fertilizer effect. You cannot expect corn meal to work against the disease once you have used a chemical fungicide. The chemical fungicide kills off an important part of the biology that makes corn meal work. One of the problems using fungicides in the south is the temperatures get above 80 degrees in April and don't come back down until November. The fungicides that work have restrictions on temperatures that keep us from using them the entire time when disease is active.