And, When? How did you water it? How did you mow it? Did you fertilize? Did you till in compost? Did you use any herbicide, fungicides, or insecticides? Did you roll the new sod down with a roller? Generally it is hard to hurt soil unless it was overdosed heavily with chemicals or tilled with woody stuff. Even then it can be recovered.

Watering = trying to stick to once a week with deep watering. But it's been raining a lot over the last few weeks up here in MA so not that much irrigation. But sometimes I water twice a week when it gets hot as the lawn is relatively new. I dont think its a water issue. Mulch mow = yes. So I did cut it more than 50% twice in a row (with 3 weeks gap in between each time). I just havent had the time and its been raining a lot so I couldnt mow. So it's possible the clippings are causing heat/lack of sun damage. But this dead grass underneath started a while back already, so its possible the mulching isnt helping, but I dont think its the root cause. Fertilizer = yes, once this year in April. Scotts with crabgrass preventer. Shade = in the mornings from home, but from around midday it gets full sun until 7-8pm. Sun isnt an issue here. If anything, the lawn gets hit by heat in the height of summer, being exposed for so long. Not sure what species this grass is (I think Kentucky Blue), but it doesnt do well in heat. But again, sun isnt an issue here. Other = I did put down compost in April. The grass was pretty covered, but emerged as a rich green. It looked fantastic. I'm not sure if it may be doing something to the lawn now though, a few months later? Any other thoughts? I really would like to fix this. I'm worried about all my hard work going down the toilet. Every day I see more of these spots. Thanks.

The mantra for watering is deep and infrequent. Deep means 1 inch all at one time. Infrequent means monthly in the cool months working your way toward once every 7 days as the days heat up. This is not a rule of thumb but guidance - if the temps are above 90 degrees F, then you should be watering more toward once per week. Between 80 and 90 should be about every 2 weeks. Lower than 80 and it's more like every 3-4 weeks. There are other factors including sunlight, humidity, cloud cover, shade from buildings and trees, soil type, soil depth, grass type, grass height, etc. Rather than trying to keep mental track of all that, it is best if you watch the grass for signs that it is drying out. As soon as any part of the yard looks dry, it is time to water the entire yard. If it has been fewer than 7 days in the summer, then water longer. No plan is ever perfect. There are some fungal diseases which cause the grass to dry out and look like it has not been watered enough. If you are certain the soil is moist, but the grass looks dry, then you likely have a fungal disease. Yes, there are fungicides. I use an organic approach so I don't know what the chemical fungicides are. I believe Immunox has been mentioned. Before you get one, read the entire label looking especially for the part about what the maximum temperature should be and rainfall. Summer is not a great time to treat for fungus because of the high temps.

I don't need to restate anything I've already said in the seven years since this topic was started. What year is this? 2016? Okay I've used cornmeal on my lawn every year for the past 14 years and it's worked for me. Your mileage may vary. It does not seem to work against red thread, rust, or whatever the fungus is caused by 2 weeks of saturation rainfall. But it does work against the disease caused by blocking off the air to certain grasses. Here's the entirety of kimmsr's link text. I had previously reported that cornmeal was being tested for use as a fungicide, siting a study by researchers at Texas A&M Research Station in Stephenville, TX that was highlighted by Howard Garrett, the Dirt Doctor. I tried it around a couple of tomato plants, but the results were very disappointing. The cornmeal first caked and later turned moldy - not an auspicious experiment. I was then notified by someone at Cooperative Extension in Washington State that the initial testing was for a specific problem under specific conditions, not for a general purpose fungicide. Even then, the cornmeal did not show any promise. It would have been nice if something as available and safe as cornmeal turned out to be effective to, but that is not the case. Cornmeal is not an effective fungicide. -Marie IannottiGardening Expert The Stephenville experiment was done in the 1990s. The specific problem and specific conditions were a variety of assorted fungal diseases on peanut plants. The suggestion was made that by using ordinary corn meal against a variety of diseases (which are common in all gardens), that a farmer would get the same effect as crop rotation. What that means is by using the corn meal a farmer would not have to rotate his crops every year, and he could plant peanuts year after year. That is a huge bonus for a peanut farmer. The paragraph on corn meal was buried in a very long list of possible attacks against disease in peanuts. Doing an experiment once is not considered to be scientifically relevant. Why it was not continued or picked up by other researches is beyond comprehension...unless someone with deeper pockets did not want the research done. TAMU was well known as deeply anti-organic in the 1990s and 2000s. From what I've seen the 2010s are only marginally better than previous decades. As Betty said in her original post corn meal worked for her. It worked for me, too, 14 times. I believe it was working for Ms Iannotti, too, but she did not recognize it as working. She said the corn meal turned moldy. That mold she was seeing, assuming it was the blue-green trichoderma, is exactly the fungus that works against her diseased plants. By not knowing what she was doing, she missed an opportunity to learn something.