That doesn't look like clay to me. Have you ever done the jar test?

I would rather work on increasing the organic content of the soil and let the worms aerate naturally. I don't think core aeration helps all that much in the long run, unless you've got a bad thatch problem, which you don't.

If you do core aerate, I would just leave the cores on top. If you fill with topsoil, there's no guarantee that the topsoil is going to be any different than what you've got now (topsoil is the soil at the top, so what you've got there is topsoil).

There's virtually no organic content in the soil. I've done the jar test as well as lab tests. Both confirm the same thing.

My photos show what used to be large clumps of soil that were flattened or sliced up with a shovel. Whether it meets the technical definition of "clay" I don't know, but I can tell you this. Several years ago we were trenching for a retaining wall in the backyard. A clump the size of a grapefruit was accidentally kicked from higher ground and it hit me square in the back. The clump never broke apart. I had a bruise there for weeks.

What did the jar test tell you about the breakdown in terms of sand, silt and clay?

If there's no organic content, that sounds like a good reason to try to increase it. When I bought my house, my soil had almost no organic content. I mulch mowed, mulched the autumn leaves into the lawn (and sometimes neighbors' leaves) and used coffee grounds from Starbucks as fertilizer.

At first, I had almost no worms and I could only water for about 15 minutes before it would puddle. Now I've got a lawn full of worms and I'm not sure how long I can water, but I thin I start watering at midnight and finish around 5 (with 4 stations, so around 1 hr 15 minutes per station average). No runoff.

What kind of grass do you have?

And where do you live? Zone 10 doesn't tell us enough. Can you give a zip code?

I have no idea what the jar test revealed in terms of soil breakdown. Don't remember. The lab tests revealed high nutrients across the board EXCEPT nitrogen. And of course the organic content was virtually non-existent.

While I appreciate your enthusiasm for organic methods such as mulch and worms, I must confess the financial savings cannot be understated. Our local corrupt politicians have failed to adequately fund water main replacement. They counted on high water usage to pay for repairs. After the recession hit in 2008, water consumption fell 35% so now they can't afford it. We're already paying $200/month in the summer months for water, and that's for 1 hour of lawn watering per week.

Their latest scam is a 10% water rate increase each year over the next 10 years. It's getting to the point where I'm seriously considering ripping out the grass altogether and replacing it with rock and drought-tolerant groundcovers.

I guess getting your location is even more important now. I want to make a mental note to not look for a job there.

To do the jar test you fill a jar half full with soil. Then fill it all the way with water and a few drops of soap. Shake it up until all the soil goes into suspension and let it sit. If you search the forums and Internet for "jar test" you can find how to interpret the results. Even sand can be made to clump like clay with the right additives. Concrete, for example, only has a little cement in it.

I think your garden guy is trying to sell you products. Adding more topsoil will only raise the level of your lawn. That can be as big a problem as anything. Had you caught me a year ago, I was leading the anti-topdressing bandwagon. I seem to be over that but I am still reasonably against top dressing unless you have low spots to fill. If you were going to aerate, instead of topsoil, scatter compost or finely shredded mulch into the holes. The compost/mulch is organic matter. As the rest of the soil melts back to fill the holes, the organic matter will be there to greet it.

Another method that really works to soften soil is to spray it with shampoo. Use the cheapest generic baby shampoo because it has the least additives. Fill you hose end sprayer with the shampoo and adjust the dial so that you just see it coming out foamy. Spray that right before you irrigate or while it is raining. Do that twice a month for a month or two and you will have greatly improved the ability of water to penetrate the soil. That will allow roots to grow deeper and your beneficial fungal population to increase. Your soil should be soft (not mushy) right after you water and then get hard after 5 days or so. This is a good thing. My soil is so soft after watering it feels uneasy to walk on, but it is not soggy at all. Just soft.

By far the best way to reduce your summer watering is to replace water loving grasses with prairie type grasses. Look on this forum for the recent discussion about grasses in the high desert. There is a list of grasses in that thread that bpgreen has in his lawn. He lives in Utah with very little precip. In Atlanta you might be able to go without irrigation just on your rainfall. The one kicker is you have to have full sun for most prairie grasses. And when I say prairie grass, they are the same grasses you find in the prairie but when you mow them like turf, they look pretty darned good.

Please tell us where you live. If you're serious about the drought tolerant grass/ground cover approach, I may be able to help a lot, but it really depends on where you live.

I'm not sure I understand this part:
"While I appreciate your enthusiasm for organic methods such as mulch and worms, I must confess the financial savings cannot be understated. Our local corrupt politicians have failed to adequately fund water main replacement. They counted on high water usage to pay for repairs. After the recession hit in 2008, water consumption fell 35% so now they can't afford it. We're already paying $200/month in the summer months for water, and that's for 1 hour of lawn watering per week. "

A big part of the reason I took the approach I did was that we had an option of getting unmetereed water for irrigation in our neighborhood. When they were telling how much it would save, I couldn't believe the numbers they were using, but I wasn't watering as much as my neighbors did. I didn't get it, but since so many others did, the water usage dropped and they jacked the rates. So I worked on my lawn until the water could penetrate deeply and started growing grasses that use less water and have deep roots. I now pay less for my metered water than my neighbors do for their unmetered water.

My bad, location is Orange County in Southern California. Zip code 92821. The sod is supposed to be "Marathon Hybrid Fescue".

A different type of grass would be a welcomed change. Do you know of anything that is both drought-tolerant and needs mowing only twice a month? That alone would cut our mowing costs to the gardeners in half. We have about 2000 square feet of sod.

The guy at Armstrong nursery warned me about the topsoil problem.

He said to collect the cores in buckets or a wheelbarrow and then slice them up really good with a shovel. With the 5-gallon buckets measure how much soil was removed.

Take that amount (say 20 gallons) and multiply it by .75 or .85 and that's how much topsoil to rake into the yard.

What do you think...is this any more acceptable?

Orange County is a bit hotter than where I am, so I don't think the options that worked for me would be a good choice for you.

If so, and you don't mind a grass that has fine blades and should be mowed at about 4 inches, you might want to go with Buffalo Grass. UC Verde is well adapted to your area.

It might not get as thick as some grasses, but once it gets established, it only needs about an inch of water a month, 1/2 lb of nitrogen a year (although that's optional), and mowing maybe every other week to once a month (if you don't mind a lawn at about 6 inches, skip mowing altogether).

It probably wouldn't go dormant in OC at all, but if it did, it would snap back. It also fills in blank spots via stolons (above ground runners).

Somebody in Phoenix grew UC Verde and created a blog about it.

I also found and this thread and this thread where it's discussed as an option for your area.

I think somebody in one of those threads even said that once they got it established, they never had to water again and somebody (maybe the same person) said they never mow theirs.

I had something else prepared and then I realized it was disjointed. It seems like you have one major issue that is leading you all around for a solution. The problem is your water costs. Is that a fair statement? Then the solution is how to limit your watering and still have a presentable lawn. This was the situation bpgreen faced. Unless he posts a picture, you'll have to trust me that his lawn is more than presentable.

Far and away the best thing you can do and still have a lawn is to plant the native grasses that bpgreen will suggest. As far as I know most of those grasses will easily survive in Brea as long as they are not under a tree canopy. In your area, with the late night and early morning fog, you may never ever need to water the lawn. I would suggest you could seed these grasses into your current lawn, water to get them up and growing, and then stop watering completely to let Nature take Her course. The time to do the seeding would be in late August or when the summer night temps start to fall from their highs.

Until then you have to live through this growing season. Here's what you can do to limit your watering needs.

Compost
Compost is an organic material made from decayed food and animal manure. Excellent compost smells very fresh. You could hold a heaping double handful up to your nose and not be repulsed by it at all. Even year-old horse manure smells fresh as a daisy. Compost is a rich organic material that has the rare ability to hold moisture. Morning dew is captured by compost and used to manage soil moisture. This ability was discovered by a Soviet soil scientist a long time ago and suppressed during The Cold War. His papers are on the Internet if you can read Russian, but I digress. The app rate for compost is no more than 1 cubic yard per 1,000 square feet of lawn. Sweep it down into the turf with a push broom or rake. The broom is less back breaking. Compost is the most expensive thing you can apply to your lawn, so use it carefully. In my area it costs $40 per cubic yard plus delivery charges. Where do you get compost in Brea? Probably not at Armstrongs. Really good compost does not come in bags. Check this map for suggestions. Municipal compost is not usually the best (by a long shot). Excellent compost has certain features. It smells wonderful, it is room temp (not hot), and it is made of unrecognizable pieces of organic material. If it has twigs and sticks in it, pass and get something better.

Water properly
It seems you have the hang of this. Deep and infrequent is the mantra. Once a week, all at once. Do not let runoff to occur. If you get runoff, then stop immediately and let the water soak in. Then resume watering after 15-30 minutes.

Mow high
Tall grass uses less water than short grass. There are several reasons but the most obvious is the tall grass shades the soil and lowers the soil temp. Lower soil temp means less transpiration/evaporation.

Fertilize
Your grass is thin. If you fertilize it the grass will become more dense. Dense grass provides more shade as discussed above.

If you are still worried about your soil being hard and low water penetration, forget about aerating and top soiling. That is far too much hassle. And I say that not as an Armstrong sales guy, but as a person interested in soil and a forum participant for about 10 years. It might have other benefits but alone, it will not give you much improvement in hardness. I know and respect many people who swear by it, but they have unlimited water. Spray your lawn with soap and see how you like that. I guarantee that if it does not work for you, I will personally be sympathetic to your plight ;-) But I really think it will work. The guy I learned it from, and the guy who seconded the suggestion, are very (VERY) serious lawn nuts in the Northeast. They use a much more complicated recipe but it amounts to home made shampoo made in a 5-gallon bucket. Based on their suggestion I tried it and immediately dropped a method I developed several years ago. Soap is better. Jerry Baker was right about soap.

If you are interested in a low cost/low hassle organic program for your lawn, flip over to the organic gardening forum and look at the FAQ. Near the bottom of the list is the Organic Lawn Care FAQ. That FAQ has been downloaded tens of thousands of times and has convinced a LOT of people to give the organic approach a try. You won't read about it in any book or even magazine. It is based on science from the 1990s and early 2000s. Plus it is so simple that about all you could write about it would be a pamphlet. The biggest problem with it, especially in California, is finding fertilizer materials. Generally you get the stuff at a feed store. Inside a metro area like yours, my first choice would be alfalfa pellets. For some reason you can always find rabbit food in a 50-pound bag. Your first thought would be, "Where would I find a feed store in Brea, CA?" Here is a map to your local feed stores. We've run the costs in this forum many times. It comes out very much the same as a synthetic chemical program.

By the way your soil looks just like our soil in Riverside when I was growing up. Wish I knew then what I know now.

Great posts from both of you.

Yes, it's a fair statement to say that watering costs are the primary factor here. That, along with $35/week to have the lawn mowed. With the way things are going, paying $2000/year for maintenance of the current lawn is not far off. The mere thought of that is sickening, especially with current unemployment and retirement not far off. Something has to give.

We rarely have morning dew or fog during the summer. I'm sure you remember the "June Gloom" marine layer that often shows up May thru July. The last few years it hasn't had much of a presence though.

I get compost from a landscape supply yard in Anaheim. They have lots of soils, rock, mulch, compost, etc. They filled up the back of my truck for $45. The compost is ground up and finer than potting soil. No large chunks. I was really impressed.

Previously I asked whether aeration or power raking would be appropriate. Then I inquired about using a sod cutter to lower the grass level.

I really need to do something, even if it's just for 2011 to prevent the dead spots from coming back. What should I do? I can rent any of these machines from my local Home Depot for $60 to $68 per day.

The photo below doesn't do the hillside justice. Because of the sod being too high, water quickly runs off down the driveway. I'm rarely awake at 5:00am to stop it.

{{gwi:83922}}

I'll also try the soap.

Based on David's post, I looked up some climate info about your zip code.

I then did some research on some options.

Your summers are actually cooler than mine, but your winters are warmer.

You could probably use either a warm season lawn or a cool season lawn. According to what I could find, most of the grasses I'd suggest aren't native to your area, but I think they'd do well.

If you want to go with a warm season lawn, you could use Buffalo Grass (use plugs or sod). You could add some blue grama to that (I'd seed it). They do well together. Grama is more of a bunch grass, but it does spread a little via tillering (especially if mowed) and some people let it go to seed to spread (although that would be a little tall for a lawn setting in my opinion).

If you went with cool season grasses, you could use a mixture of streambank wheatgrass, western wheatgrass and sheep fescue. If you don't care if it's native and just want low water, crested wheatgrass is also a good choice (it comes from siberia, but is well adapted to western US).

Uta seed has a mix that is already put together that they call their Cabin Mix. If you want to make your own mix, you could pick the seeds from their price list.

There are other options too, but that's where I've gone the last few times for cool season grass seed.

It's too late to sow cool season grasses and too early for the warm season grasses. I'd wait until your highs are in the upper 70s for a while before doing warm season grass. For cool season grass, I'd probably seed once the heat breaks and the fall rains come (looks like most of your precipitation comes from October through April, just like ours).

If you go with the cool season grasses, you'll probably need to water 3-4 times a year. But only water if the lawn gets stressed. If you go with warm season grasses, you might not need to water at all. But they're really only an option if you have full sun. If you've got a lot of trees, retaining walls, etc, go with the cool season lawn.

Whichever route you take, kill the existing lawn first. Despite the huge difference in requirements, you'll end up with patches of fescue if you don't kill it first.