Question
Our backyard is made up of many large, old trees, I'd describe as mostly shade.  My husband attempted to start a lawn last summer, putting down topsoil, leveling it off, fertilizing, etc.  It appeared to be doing well in the spring, but now has patches of clumpy dead grass, and numerous mushrooms, some in a circular pattern.  He tried to aerate recently. He waters the lawn a few times a week for about an hour.  We also have a dog, but he scoops up after her every day.  I do realize the dog's urine could be burning the lawn. I think it is being overwatered.  he would like to know if he should put down a shadier lawn seed, he originally used shade a mix. We live on Long Island, the North Shore  Thank you

Answer
Grass is Solar Powered.  'Mostly Shade' explains at least part of your problem.  You hint at several others as well.  Poor guy - all the diligent work and still no Lawn.

I suppose you know that those circular mushrooms are Fairy Rings.  Fungi decomposing wood down under, and their 'flowering' Mushrooms above.  Watering 'a few times a week for about an hour' is definitely over the top and contributes to the Mushroom bloom.

That's not a bad thing.  Hidden Fungi in your soil are using all that moisture to speed up their rotting of the wood.  There may have been a tree down there at one time.  Could have been years ago, and it's still decomposing.

Topsoil is a very temporary fix, as you have learned -- so long as Fungi are down there dissolving wood, you will have Mushrooms.  You can rake them away if you dislike them or if you are concerned about, say, the dog or children eating them.  Note however that if you apply any Fungicide -- organic or otherwise -- you destroy the Fungi and halt, completely, their work, which is rotting of the dead wood.  Fungi are the ONLY organisms that can decompose the Lignin in wood.  There is not a Bacterium on the planet that can do that work.  Fungi make the Enzymes, and Fungi have to do it -- unless you are ready to hire someone to dig up your backyard (for a cesspool for instance) and yank the old tree stump(s) out of there.

Your dog may be doing some damage.  But Fido's calling card frolics cannot be blamed for the failure of an entire Lawn.

Let's break this down like Scotts does into Steps.

STEP 1.  SUNLIGHT SHORTAGE.  'Mostly shade' is a big part of your Grass problem.  MOST Cool Season Grass just CAN'T grow in 'mostly shade'.  You need just the right Grass for this problem.  You need state-of-the-art Grass that is highly efficient when it comes to Solar Power.

Most people go over to the garden center and read the labels, then they pick a 'shade' mix of Grass, go home, plant it and wait.

Now, there's no government regulation on that term.  Anything can be called a 'shade' mix.  Anything can be called 'topsoil'.  These are very generic terms that can be almost anything.  Most people don't realize this, and they are so unfamiliar with Lawn care that it never occurs to them that they are being had.

But not all Grass is created equal.  Thanks to all kinds of expensive r&d across the country on Grass, there is some pretty fancy, talented Grass out there.  You just have to find it.

There is a new Bluegrass hybrid I think you should know about.  It's called 'Supernova'.

Seedland describes this as 'Supranova Supina' Bluegrass as 'the most shade tolerant, wear resistant, cool season turfgrass on the market in the US and Canada.'  Ordinary Kentucky Bluegrass is a fussy, demanding Grass that MUST get TONS of Sun to grow and look its best.  Supernova is much more compromising.  It needs moisture, it needs cool temps, but for you it is just what the doctor ordered.

Supernova is not sold everywhere.  Since it is very new, it is hard to find, and there is limited availability.  I recommend that you stay away from a 'mix' that boasts it is part Supernova -- get it solo instead, not 'mixed'.  I don't know who on Long Island sells it today, but if it's not at a store near you, order it from Seedland.com:

http://www.seedland.com/mm5/merchant.mvc?Screen=CTGY&Category_Code=BG-SUPINA

Watch out for stickershock - the price of this seed is insane.  Think of it as Botox for Lawns.  

Bluegrass as a genus loves a diet high in Nitrogen.  So a bag of all-American White Clover mixed in with your Supernova seed will incorporate Nitrogen au natural -- less work for you, long term Nitrogen treats for your Supernova.

This is the cost of your Shady Situation, unfortunately.  If you can't bear to spend as much on Grass Seed as a new Prada bag, there's another choice, albeit less glamorous, less fancy, but it's green.  Cornell University's Lawn Care website (http://www.gardening.cornell.edu/lawn/lawncare/index.html) addresses your situation in its 'Coping With Shade' page:  'Lawn grasses need at least 4 hours of direct sun a day.  If they receive much traffic or wear and tear, they need a minimum of 6 hours.'

Let's read that again: 'Lawn grasses need AT LEAST 4 HOURS of direct sun a day.'  More for kids and pets.

To address this, you can (a) thin out your tree canopy, and (b) plant Fine Fescue under those trees.  You can read all about it in the Cornell Coop Extension's Fine Fescue fact sheet (http://www.ccenassau.org/hort/fact_sheets/c109_fine_fescues_dec01.pdf).

At last year's tests,  the top Fine Fescue grown at the Rutgers University Grass Testing lab in New Brunswick , N.J., was a variety entered as 'Pick CRF 1-03'.  And the Oregon grass farm that bred Pick CRF 1-03, Pickseed West, has named it 'Garnet'.   If you want to get your Green-up quicker, you can mix in 20% of an improved perennial ryegrass -- like Pickseed's 'Fiesta 4', which is recommended for Long Island; it will get the green going while the much slower Fescue or your Supernova rev up their engines.  

STEP 2.  YOU'RE STUMPED.  If there is a serious tree stump under your soil where those Mushrooms are, it will be hard to grow Grass there, because large numbers of Fungi will make it inhospitable to most vegetation.

Watch that area when you're done with this project.  Monitor the color, the health, the lushness of the Lawn.  If it fades to black again, it's time to look for another plan.  Consider plunking a Birdbath right in the middle, surrounded with Pachysandra and/or Hosta.  Consider a BBQ.  A pool.  Something, anything, but not Grass.

Me, I vote for the Birdbath.  It is less permanent than some of the other choices and does not block air from reaching down under.   Fungi need Oxygen.  These are aerobic organisms.  Besides, with all those trees, those Birds will enjoy a water feature nearby.

STEP 3.  SOIL SECRETS.  What's in YOUR soil?  Long Island Compacted Clay?  At best that's an educated guess.  You don't REALLY know what's down there.  What's the pH?  salt content?  Phosphorous and Nitrogen and Potassium?  What's your soil's Cation Exchange Capacity?  You need to know these answers.  Unless you know these things, they're a big secret.  But you can unlock those secrets.  With a soil test.

All that aerating -- an educated guess.  Wanna bet you didn't need to do that?

Get your soil tested.  Not one of those do-it-yourself kits at Home Depot and Lowes.  A REAL Soil Test by a scientist.  Late winter/Early spring is the best time to  identify soil chemistry problems.  

The Rolls-Royce of soil testing is done  by an elite international organization which happens to base one of its two U.S. labs in Port Jefferson, Long Island.  Fill out the proper forms, follow  their directions and submit as instructed to the Port Jefferson Soilfood Web Laboratory:

Soil Foodweb New York, Inc.
555 Hallock Ave. - Suite 7
Port Jefferson Station, NY 11776
Phone: 631-474-8848
[email protected]

For an abbreviated, cheap but legitimate test that won't break the bank, go to Cornell University's soil scientists, who will test your Grass for a VERY modest fee:

http://www.css.cornell.edu/soiltest/Soiltest.html

Get the whole works.  Every decision you make will be determined by what's in that soil test.  I personally love the ultra-expensive Soil Foodweb's services, but I am crazy and I love to hear about the species of flora and fauna in the soil.  

Just for one minute, let me explain why I love to know these things.

That flora/fauna information is like knowing who's on first, if the bases are loaded, the B.A. of the guy up at bat.  Do we have the right kind of Bacteria?  Is there enough?  What kinds of Nematodes are in my soil?  How many are there?  Bacterial Feeders? Fungal Feeders? Predators? Do I have any Tylenchida (plant parasites)?  Any Aphelenchus?  Ditylenchus (Stem and Bulb nematodes)?  Aphelenchoides (cause blasting in many herbaceous perennials and attack clover, orchids and chrysanthemums)?  I NEED to know these things.  You are the coach of your soil.  You can manage your microbes to win the World Series.

But that's another story for another day.

Aerating is a great idea -- but only if you incorporate organic matter into your soil and correct it for deficiencies.  Your soil is most likely IM-perfect.  What's it missing?  What's it got?  What do you NOT need to put in?  A soil test will give you ALL those secret answers.  Simply aerating to break up the Clay is NOT helpful, because you scare away the Earthworms and shake up the soil foodweb.  Those two things -- the Earthworms and the Soil foodweb -- are important allies for processing Organic Matter.  You want to be their friend.  Not their worst nightmare.  If someone came along and bulldozed your house, would you greet them on the way out?  Neither would the Earthworms.  Or the Microbes.

You do not have a complicated problem here.  None of this is unusual.  Especially in Long Island.  We're two months from Seed-Sowing Season here.  Get your soil tested.  Put away the hose.  Call the treepeople.  Keep mowing -- you do nnot want a single weed to set seed this season!  My guess is that some Pelletized Lime could be put down right now -- it's not something you want to add when you fertilize, and it will make your soil more microbe-friendly.  Plus it takes time to work.  Do your sampling, and keep a record of what you apply.

Any questions, let me know.  Nice meeting you.  Please keep me posted.  And would you please do me a favor and rate me at the end of this answer?  I am hoping to be listed on the 'Top Allexperts' at the end of the year, and I need a lot of NOMINATIONs for that.  I would appreciate it.  Thanks.