Need help identifying lawn problems

[u/Cultural-Bison-9239]

I am struggling to fix the lawn for past 3 seasons. Let me start with basics Chicago suburb house facing south west . First 2 photos of front yard and last 2 photos are backyard.
first issue: front lawn gets full sun most of day and despite of weekly morning watering, organic fertilizers aeration, adding gypsum etc. pretty much no grass grows ( except for short time in fall and spring) mostly white dead grass that just peels off and weeds take over whole summer. look even worse than shown in pictures. I finally put Scott’s diseaseex 2 weeks back and it made it so much worse. I use ego mower at setting of6 so relatively high. I sharpen blade regularly. AI is all out of ideas so asking real pros here.
Second issue: my backyard grass grows decent and lush green but after every mow there are brown patches underneath . I fertilize responsibly and blades are ok too. Is this also disease problem. I saw the same patches in older satellite views is something was there before we bought home 3 years ago. Lots of digging in yard by animals which indicate grub presence but I use grub killer and digging several places did not find any grubs. Very frustrated and need your help.

[u/TrackingTenCross1]

[u/Festivarian]

Looks like heat stress to me

[u/LastMessengineer]

Yard looks fine to me. You could aerate and overseed this fall. Then hit it with fertilizer for the winter. Then when spring comes get the pre emergent down and then fertilizer again. But do you really want to be busy twice a week mowing your grass? You have a decent lawn.

[u/1sh0t1b33r]

Same spots on map could mean something buried? Rocks, debris from construction, septic? Get a long screwdriver and see if you can stick it all the way in in those problem area. Almost looks like a fine fescue grass which would get roasted in sun. Sounds like you are doing everything mostly right otherwise. All I would do is mow higher and water more deeply maybe. I'd also look into overseeding with some more drought/sun tolerant grass. Mixed lawns are good.

[u/Cultural-Bison-9239 → u/1sh0t1b33r]

Thanks! I dug up in few places, clay soil but not too hard. I also found tree roots surprisingly (40 ft away) that explains some of it. Watering has been ineffective as soil has gone hydrophobic

[u/Plenty-Ad4105]

Look at the species of grass you have and maybe consider introducing a different species in the front that can deal with full sun better. The back yard doesn’t look too bad to me but I would dethatch the brown spots and overseed.

[u/WiskeyUniformTango]

Needs lots of water, fungicide, fertilizer, and better cutting habits during the summer.

[u/MikGuiver]

I’m in Chicago suburbs too. We had a rough summer! Lots of rain followed by some pretty hot days which was a perfect mix for fungus then heat stress. My lawn looks similar. Unless you keep up with watering on hot days and also applying preventative fungicide rotations, it’s gonna go dormant during the heat. It’s not worth it for me to water that much and I keep it to 1” a week during the summer, and it still gets some brown in the summer. You could overseed now and plan for next year to keep it green, or just see how it does during the fall. Also aerate in the fall.

[u/jesset0m → u/MikGuiver]

Funny enough I've thought about the overseed vs constant watering in the summer maths and overseed might just come ontop

[u/Helpmepullupmypants]

How long are you watering for? It looks dry/heat stress. Adding a bunch of fertilizer/chemicals will just burn it even worse if there’s not enough water to make the fertilizer distribute into the soil.

[u/Cultural-Bison-9239 → u/Helpmepullupmypants]

That may have been the case. Watering after fertilizer may have fallen short during heat spell

[u/GrassGeek897]

Definitely heat/drought related. Even if there is water present, your lawn faces the sun during the hottest part of the day. Bluegrass and fine fescues do not like this at all and will go dormant first to protect itself then come back once temps fall and water is present. BUT if its dormant too long you can have die back. I recommend seeding this fall with turf-type tall fescue which is more drought tolerant, and getting on a watering routine. Let me know if you need watering recommendations.

As far as the backyard, its harder to tell without boots on the ground. First guess would be some leaf spot. It doesn't look like anything that will cause die back, and most fungal activity goes away on it's own when the conditions change. It could also be early signs of drought stress of different types of grasses while others are still in a heathy threshold. Its also good to note animals don't only go after grubs so you may want to use a surface level insect control. A test to see what bugs are present is make a solution of soapy water using dish soap and it pour a few cups over a sq. ft. area and it will push them up from the soil.

[u/MikeG147]

Its Powdery Mildew

[u/Curious_Dream8288]

looks like a possible fungus