Does water seem to puddle up right in that spot? When you've tried everything, then it's time to look into a soil test. The best soil test for any money is the cheap one at Logan Labs in Ohio. The least expensive of all the comprehensive soil tests is the cheap one at Logan Labs. They test everything. You can pay a lot more and get a worse test. When you get the LL test back, I can help you find a place where there are volunteers (like me) who will read the test, tell you what it means, tell you what you need to fix it, where to get the stuff, how much to apply, when to apply, and more if there is more. They just don't do that on this forum.

Mushrooms that grow on the woody roots of trees are an indication that there is an extensive amount of interior decay within that tree. There is nothing you can do about that. Removing the mushrooms is sort of like dead heading a perennial plant: the flower is gone but the plant is very much alive and thriving. So is the fungal organism inside your tree...mushrooms are simply the reproductive body. It is likely that this tree has had this rot for many years. I'm also worried about the sawdust, would could mean the presence of borers. Actually, each and every single symptom you've described indicates problems with your tree, I'm sorry to say. You already seem to understand that it is growing in what can be accurately termed 'a hostile environment'. Given the location, which you can't do anything about, and the probable maturity of this tree, I don't think I could give you much hope. However, a hand-on inspection might result in a completly different story! Why not get the yellow pages out and talk to an ISA CERTIFIED ARBORIST (ask to have proof of the certification). Please know that no responsible and educated arborist will recommend treating the tree rot (mushrooms), or filling the holes, or climbing the trees with spikes in order to prune the dead wood. (If the tree is in very bad condition, they won't be able to climb it at all!) Good luck...maybe someone else has a more positive outlook than I do, lol! I know that you are attached to your tree.

The lawn care nut is interesting, but as I remember he spends more money than I think you need. We don't mind what you do and really don't mind if you ignore the suggestions you get here. If you do ignore them, you might get a follow up explanation about why ignoring it might cause problems. Other than that we can't really come through the screen and choke you into submission. Of what you have done in the past, not watering was the worst thing with mowing too low coming in as a close second. Proper watering, in your case, will take your lawn up several notches. Combine that with proper mowing height and it should become very impressive. Fertilizer is nice to use, but watering and mowing are going to give you the most bang for your buck. Notice that I'm not urging you to aerate, topdress, overseed, dethatch, or anything that costs money. You were already mowing, so all we're adding is proper watering and possibly some organic fertilizer. newtolawncare covered proper mowing. Almost all grasses look and perform best when mulch mowed at the highest setting. The exceptions are bermuda, creeping bentgrass, and centipede; so you're in the mow high category. Do take a look at the lawn nut to see what it looks like when mowed high. Proper watering is different from what almost everyone wants to do. Everyone seems to want to water 1/7-inch every day to get an inch of water per week. That's exactly the wrong approach. First of all 1 inch per week is only in the hottest heat of summer. Secondly frequent watering develops shallow roots which cannot survive more than a few days with a broken sprinkler system. The top growth shows it by looking deadish much of the time. I'll show you pictures below. So proper watering means deep and infrequent. Deep means 1 inch all at one time. Put out some cat food or tuna cans and time how long it takes your sprinklers to fill the cans. That will be your watering time from now on. I use a hose and oscillator sprinkler to get the most even coverage. If you get high winds, the oscillator won't work without some adjustments. As for frequency, that is temperature dependent. When the temps are in the 90s, deep water once a 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 the 70s, water once per month. By allowing the soil to dry out completely between watering the weed seeds will have trouble germinating and taking root. The tall grass helps by casting a shadow on the soil making it harder for weeds to sprout. Here is a picture of morpheuspa's lawn in eastern PA. He deep waters and his neighbors do not. Fertilizer. Generally we fertilize once in the LATE spring, once in early fall, and again in late fall. Late spring is Memorial Day to be safe. You'll see lots of people fertilizing early. What that does is burn out the grass's nutrients too fast which requires them to fertilize again in late spring again, anyway. Just wait it out and you'll see your lawn grows just as fast as you need it to. One thing that will help next spring is your late fall application of fertilizer. I like to use organic fertilizer because it works, doesn't cost that much more on small lawns, and is insensitive to using too much. I have a picture showing it works for you, too. The organic approach I like is to use animal feed from your local feed store. You can certainly buy name brand organic fertilizer but it costs about 6x more than animal feed. In order from highest N (really protein) to lowest we have corn gluten meal, soybean meal, cottonseed meal, alfalfa pellets (rabbit chow and my fertilizer of choice), ordinary corn meal, and used coffee grounds. Corn meal and coffee grounds work, but not like CGM and soybean meal. I look at cost and availability. The application rate for the high protein materials is 15 pounds per 1,000 square feet. When you get to the lower protein materials you need at least 20 pounds per 1,000. If you make a mistake consider this: you can go up to 60 pounds per 1,000 before you have problems with the grass (you'll be burying it under fertilizer). That's what I mean about no hassle. It's really hard to make a mistake with organics. Having said that, chemical fertilizers certainly work, too. Be certain you are not mixing herbicides with fertilizer as in a weed n feed product. If you need to fertilize, use a fertilizer. If you need to kill weeds, spot spray the weeds with a targeted liquid herbicide. Follow the bag instructions closely unless you have a soil test which tells you to boost your chemistry. Here's a picture of mrmumbles lawn where he was testing alfalfa pellets.This picture shows the improved color, grass density (this is zoysia) and growth. The picture was taken in mid June, 2010, about a month after he applied the alfalfa pellets. Organics take a full 3 weeks to see the improvement, but as you can see, there will be an improvement. A couple more things I like about organics are that my garage no longer smells like chemicals and I don't have to worry about when it's safe for my kids and pets to play on it. It's food so it's pretty safe. On the down side, critters like the organics. I keep the rodents out by putting it into a Rubbermaid bin with a top. Still there are invisible insects that are already in the bag when you get it. They eat some, but then they become fertilizer themselves when I apply. If you store it over the winter, the bottom of the bin will be rather icky with insect ick. If I did not apply it all in the fall, then in the spring I stir it up and toss it on the lawn. Your last app of fertilizer in November (more specifically it should go on after the grass stops growing but before it goes dormant) should be a high N (fast release) and low to zero P and K fertilizer. Something happens in the winter soil where this dose packs the grass plants with the nutrients needed to come out of dormancy in the spring. This is why your grass will look much nicer next spring as opposed to this spring. I don't think you need top dressing unless you have low spots that collect heavy rainwater. I don't think you need to core aerate because there are better ways to address hard soil. Yours is likely very hard, but maybe not. You're sure to have more questions. Feel free to ask.

Move those babies inside.