Leah, eventually it does recover. Lisa is/was a special case of someone who will do anything and everything to cure any minor flaw in her garden. She used to post these pictures that anyone would be extremely proud of and point out some detail not to her liking. Well, two of her pictures are in this thread. Anyway, you do not need to do core aeration. The lawn gurus on other forums have come up with a better way to do whatever you thought core aeration would cure. If you would start a new topic on Houzz and tell us what your lawn issues are, we can take off from there. Posting to Lisa's topic will not get you the attention you deserve. Be sure to tell us where you live when you post, as Lisa did with her initial post.

That is epic & I wish I had thought of it! Next year...

Heed the wisdom. It is sort of ironic that Scott's wants to sell you more product but they put that warning on one of them. Seed should be put down in the fall. You missed your chance last year. I realize they sell seed now, but now is a bad time to put it down. Tomorrow is worse and it gets worse and worse until fall. Now is a great time to prevent crabgrass, though. There is a lot more to the conflict between spring seeding and weed control, but the best thing you can do at this point is take good care of what you have. That alone should minimize the weeds. 2) No. You don't need to dethatch. Dead grass below the live grass is normal. There is also the possibility that you have Kentucky bluegrass which is still dormant. So it might look dead but it will come back. Let's all cross our fingers for that. That would mean you don't need more seed, because KBG spreads to fill thin spots without reseeding. Fescue and rye grass do not do that. 3a) Watering: Deep and infrequent is the mantra for watering. This is for all turf grass all over the place. Deep means 1 inch all at one time. Put some cat food or tuna cans around the yard, and time how long it takes your sprinkler(s) to fill all the cans. Memorize that time. That will be the time you water from now on. My hose, sprinkler and water pressure takes 8 full hours to fill the cans. Your time will likely be less. I like gentle watering. As for watering frequency, that depends on the daytime air temperature. With temps in the 90s, deep water once per week. With temps in the 80s, deep water once every 2 weeks. With temps in the 70s, deep water once every 3 weeks. With temps below 70, deep water once a month. Note that you have to keep up with quickly changing temps in the spring and fall. This deep and infrequent schedule works in Phoenix and in Vermont, so it should work for you. The reason for deep and infrequent is to grow deeper, more drought resistant roots and to allow the soil to dry completely at the surface for several days before watering again. If it rains, reset your calendar to account for the rainfall. 3b) Mulch mow at your mower's highest setting. 3c) Fertilize on Memorial Day, Labor Day, and Thanksgivingish. Once a year I would use an organic fertilizer in addition to, or instead of, the first two applications. I went completely organic after trying it once, so you might have the same experience. 3d) Spot spray weeds in mid April. Use something like Weed-b-Gon or Weed-b-Gon Chickweed, Clover, and Oxalis Killer. Don't use a granulated herbicide as it is a waste of herbicide and a soil contaminant. 3e) Don't use an insecticide unless you have insect damage on your lawn. Just because your neighbors use a preventive insecticide every June, don't fall for that. 3f) Get ready to reseed if you need to in August. Then do the reseeding in September (in NJ). That gives the grass time to come in and for you to evaluate whether you need more seed. 3g) The last fertilizer application of the year is a winterizer. It should be a high N, fast release product. Wait until the grass has stopped growing but before it goes totally dormant. The idea is to push nutrients to the roots without stimulating new growth, so the grass has to have stopped growing for the year. Then next spring your lawn should be one of the first to awaken. 3h) If you have hard soil when it is moist spray with shampoo at a rate of 3 ounces per 1,000 square feet. Any clear shampoo will work. Follow that with 1/2 to 1 inch of water to get it down into the soil. After 3 weeks you should see the soil getting softer after it rains or when you water. 3i) Don't get tempted to topdress with soil or sand. That will change your drainage in ways you don't want. 3j) Proper watering (3a, above) is the single most important thing on this list. If you don't get that right you will run in circles with this product or that and with aeration and dethatching when you don't need it.

Pay a teenager (or bully able bodies offspring if you have any) to simply poke a border fork, at 6inch intervals, straight downwards into the sward, then top dress with fine sand (brushing into the holes)..This will maintain enough aeration for most purposes and is a standard method for smaller urban lawns. You can also buy a hand scarifier, which will remove thin cores of turf (but harder than using a fork) and has an even worse tendency to compact the soil rather than lifting out neat cores. Mechanical aerators will remove soil and also moss and other surface gak, and are really for heavily trafficked areas and groundskeeping...but personally, I love powerful plant machinery and would hire one if I could defray the costs somewhat.