You're probably going to get some conflicting opinions about this issue, but many of us feel tilling the soil is too disruptive to the organisms already living in the soil, and doesn't provide much benefit. But the key question now is: What is the condition of the existing lawn? Does it need to be killed off and replanted? Or can it be salvaged?

If it can be salvaged, that's a lot less work than killing it and reseeding.

Also, what does the soil look like under the old concrete pad?

I planned on tilling to loosen up the dirt. I'm in the desert so it's pretty hard, I can get down 2-4 inches with a shovel. I've been worried about root penetration and the like. Under the pad is the same, with a bit of remaining aggregate from the demolition.

I have not watered the grass in over a year but it is pretty hardy and greens right up after a rain. My plans for replanting the whole thing are for uniformity in the lawn, and not have some patch in the middle different from everything else.

Hope that helps. As you can probably tell, I'm new to all of this so I know nothing but have a lot of ideas which make sense in my mind. Whether or not they make sense in reality is the big question.

The area under the pad would almost certainly need to be tilled, with the addition of compost and fertilizers before seeding. Depending on the size of the area, a soil analysis might really help, too.

I'd make sure to get up as much of the loose stone as possible.

But the other areas, if they're currently able to support healthy turf, probably don't need to be tilled. You could just kill the grass with glyophosphate, scalp the lawn, fertilize, then overseed.

I'm still a bit confused about the condition of the living grass there now though. Is it a uniform turf? If so, do you know what type of grass it is? It'd be hard to believe the soil is overcompacted if the turf is uniform and healthy.

Since you're in the desert, you may need to be concerned about the effect the concrete had on the pH of the soil. Desert soils tend to be alkaline to start, and concrete can make that even worse.

I could post a picture, though I'm not too sure how much it would help. Is there a way to post a picture?

It's a little bit of hassle to post pictures here but once you learn how, it's not that bad. First your pictures have to be located on the Internet somewhere. Most people use something like photobucket or picasa to host their personal images. If your picture is already at a hosted site on the internet, right click on the image at that site, select "Copy image location," and come back here. Then use the following coding

[img src="paste your site between these quotes"]

Except you have to replace the left and right brackets with the symbols. Check to see that the quotes are there and that the image location starts with "http://"; and ends with, ".jpg>"

Now regarding tilling the soil: the biggest problem with tilling garden beds is a little different from the biggest problem with tilling to prep for a lawn. If you have pure sand it might not be as big a problem but it might. When you till you cannot possibly get the same amount and depth of "fluff" all across the yard. When the soil eventually settles (over the next three years) it will settle unevenly leaving you with a very uneven surface to walk on. The proper way to prepare soil, if you have to, is to work only at the surface.

The best professional landscapers use a real tractor (not a Bobcat) with a box blade on the back. That blade will scrape the surface off leaving a perfect bed for seed or sod. They will build the contour of the surface so that water will drain away from all the buildings and into the street or gutter. If you have a large area to do, hiring a professional is a good idea. A good one with the right equipment will be done in an hour. If he shows up with a bobcat he'll take a full week and then probably mess up the drainage.

If you have a small area, then do it yourself. You'll have to guess as to whether you need more topsoil/sand. I would try to not bring more in because once it's in, it's in. Then level it by dragging a piece of chain link fence around with some weights on it. Drag and drag and drag and drag in all directions until you are perfectly happy with it. Then sod or seed followed by rolling the sod or seed down. The rolling will ensure good contact between either the sod or seed and the soil.

What kind of grass are you going for? And where are you in the desert? That will make a difference.

Okay, let's give this a try. Hopefully you'll all be able to see the mess that is my backyard.

As far as questions, I was unaware that concrete would affect the alkaline characteristics of the soil. Is there something I can add to counter this?

I am located in Ridgecrest, CA, about 100 miles south of Death Valley. I am looking for a grass that my kids can play on but that doesn't require a lot of water. I'm leaning toward Bermuda grass.

{{gwi:121335}}

Sulfur can lower pH. It works best if it is worked in, but it helps a little if it is spread on the surface. As David pointed out, if you till, you run the risk of the lawn settling very unevenly, so I'd be wary of tilling.

Adding organic matter can also help, although that's a long process. If it's available where you are, greensand (glauconite) helps make the nutrients available (maybe without changing the pH). You could also spray water soluble iron on the lawn when the highs are below 80F.

I don't know that much about warm season grasses, but I think the two grasses that are most likely to meet your needs are bermuda and buffalo.

Of, those, I think Bermuda is the better option. Buffalo grass is a native grass and is well adapted to low water, but it doesn't hold up as well to traffic and doesn't repair as quickly as bermuda. If you decide to go with buffalo grass, you will probably want sod or plugs and make sire you get an all female variety. If you get seeded buffalo grass, it will produce seeds and the seeds are in sort of a burr and would not be comfortable for walking/playing, etc.

I'm going to make things a little messier here.

I didn't want to bombard everyone with a verbose post in the beginning, but I can't avoid this either. I would like to water the lawn with a subsurface drip irrigation system. Doing this will require several trenches 18" apart. Part of my rationale for tilling comes from the idea that all of this trenching tears up the yard anyway.

So...does this change things?

Lordy, what a project!! I assume you're keeping the trees, too. With the trees you're going to have trouble tilling near them anyway. Roots will complicate things. Thanks for the Ridgecrest info. A high desert situation is a little different from the low desert. You have to deal with freezing temps much more than the folks in Palm Springs.

I'm going to suggest something you might not want to hear but at least it will be on the table. I would use the existing soil to fill as much of the holes as possible. Then water heavily to settle that soil. The soil will no long be level so find some soil to fill again and water again. Walk on it and do whatever you can to get it settled down. Then reevaluate where you are. I'll guess that you will have an uneven contour from the house to the wall. Now is the time to fix that by bringing in more soil or removing soil. Level it with soil and a drag, water and relevel with more soil. When you have it as perfect as you can get it, then plant your bermuda seed.

If you have grass plants in the yard that are not bermuda, you might want to get rid of them before seeding. They will become weeds in bermuda.

Regarding bermuda, do you realize that to look its best it needs to be mowed every week (no less) at a height of 1 inch or lower? And if you want it to become very dense and dark green it needs to be fertilized. Monthly fert is what many of the serious bermuda aficionados use. Keeping it dense is important if you want minimal weeds. In your case you might tolerate weeds just to have a nice place for the kids to play. If you want it to look really good, bermuda requires as much water and more maintenance than other grasses. If you don't need it to look great, then you can relax on the water and maintenance.

Regarding watering: if you bury drippers or soakers every 18 inches you will never be able to dig in the grass again. Those hoses will become lost to time. If a leak should develop, it will be a nightmare to find and fix. Instead I would suggest using a black plastic soaker hose to achieve the same result. Roll it up on a hose reel to make it easy to deploy and reel in. Get enough to lay it out at 18 inches apart to cover the area you want to cover. I use black plastic soakers to soften my soil rather than aerating with a plug aerator. I turn the water on at the faucet at a dripping rate of 1 cup per minute (or less). Then I leave the water running through 150 feet of soaker hose for a week, day and night. I like the way that works. After a week I've only used about 800 gallons of water and it all stayed right where I put it.

You've made it sound like I've got a lot of work in front of me. That's okay; I'm sure you've got more experience than I in these matters. Your suggestion...would that be after the trenching?

My rationale for the subsurface drip system is that in the summer it gets HOT - 110+ hot. I don't want to lose any to evaporation. I've also read that applying water directly to the roots rather than to the grass itself promotes better growth. Bottom line, I want to give my kids a nice yard but don't want to blow open my water bill to do it. I hadn't thought about digging in my yard afterward, such as aeration. The drippers would be 6" below surface; could I aerate at a lesser depth?

As far as Bermuda grass...like I said earlier, I heard that it was a good drought-tolerant grass and that most people in this area plant it. From what I do have on my property, I can see that it would need frequent mowings to keep it under control.

Maybe I'm wrong in my thinking. Feel free to offer any correction. That's why I'm here, to get advice from the masters! Thanks so much for all the advice so far!

In addition to heat you have wind, altitude, and very low humidity, on the order of 5%. Although your soil looks clayey I'm thinking it is mostly sand with some clay in it. If it gets wet, can you squeeze it in your hand hand have it stick together? If I'm right then you can add sandy to the issues you have.

A drip system seems like it would be ideal to solve those problems. I can see pros and cons to putting the system in before or after doing the grass. The way I would handle that is I would put the grass in first. Get it established and growing well, and then come in with a Ditch Witch type trencher to dig the drip system. When you back fill the trenches, use all the soil even though it makes a mound along the trenches. Eventually all that soil will settle back into the trenches. I had two different plumbers digging in my yard at the same time. One backfilled with all the soil, which made it mound up, and the other scattered the "excess" soil around to make a flat looking repair. Now years later the mounded trenches have melted back to ground level and the formerly flat repair needs more soil to build it back up.

Bermuda is "drought tolerant" because it does not die if you don't water it. It turns brown and goes dormant. Once it gets water again it turns green and bounces back.

Plug aerators rarely go deeper than 3 inches with their 4-inch pluggers. With a drip system I doubt you'll need to aerate. I have a technique I use to soften my soil with a black soaker hose. It uses 800 gallons per week as opposed to my sprinkler that uses 800 gallons per hour. It might take some fiddling around to get the timing right, but I don't see you ever needing to aerate.

Let me ask then - what exactly is the purpose of aerating? I'm starting to think I have no idea.

I like the idea of doing the drip system later. Means I can get the grass in sooner, without having to buy all the line and everything. I think I'll go that route.

If I do go this way...till where the pad was, leave the rest alone?

I believe my soil to be clay-ish; on the picture I posted, there is a brown metal post on the far side. See that? My wife tried digging it out, she dug a hole maybe 1' deep and filled it with water. It took ALL DAY to drain. I've understood poor drainage to indicate clay-like soil. Correct me if I'm wrong.

The purpose of aerating is to help reduce compaction and introduce air into the soil. It is also supposed to help loosen the soil so that water can penetrate better. I've got clay soil also, and have aerated once in about 12 years. I've had better better results just by increasing the amount of organic matter in the soil. I mulch mow and fertilize almost exclusively with used coffee grounds from Starbucks.

Sounds like clay to me. I'm more familiar with Apple Valley and Edwards than Ridgemont. They have more sand, but you might have topsoil brought in from somewhere.

I would not till it. For now I would fill it in to level it and then put mulch on top. Bermuda seed won't sprout until the soil temp is in the 70s anyway, so you'll have to wait until June for that. In June pull the mulch off and seed.

The purpose of aerating? As far as I'm concerned it is to help the lawn services people make their boat payments over the winter. Nevertheless there are people I highly respect who swear by it. They have impressive before-and-after pictures to prove the results. The idea is to soften the soil because it has become "compacted." They remove cores from the soil and put them on the surface. Then with irrigation the holes fill with water and the plugs on top of the soil melt back into the surface. Eventually the soil surrounding the holes melts back to refill the empty hole. However there are too many reports here in the forums of people writing in to say, "I need to aerate my lawn again. I aerated last spring but it's compacted again." I would argue that the soil was never compacted. It might be hard but that's different. A dry sponge gets hard but it does not get compacted. The same thing can happen in your soil.

I take a biological view of compaction. If the soil surface has become hard, even when it is wet, that is probably because the population of beneficial fungi is too low. Healthy soil fungi push the soil particles apart when they get wet and allow them to squeeze back together. That squeezing is felt as softness when you walk on it. First you have to have a lot of those beneficial soil fungi. If you give the soil the right moisture conditions, such as nearly continual moisture but not so much as to cut off the air, then you will find the fungal population regrowing. Think of bread: you let it sit out and soon a green spot of mold forms. If you leave it alone, within a day or two the entire bag is filled with hairy green fungus. The same thing can happen in your soil if you create the moisture conditions. Your dripper would be perfect to do that over the entire yard. Turn the water on e-x-t-r-e-m-e-l-y slow and leave it for a couple of weeks. The soil will soften due to the moisture but after you turn off the water, something different happens. As the soil surface dries out it becomes hard again, like a sponge does. Then when you wet it, it becomes very soft, also like a sponge does. This is because the fungi in the soil are reabsorbing the moisture and swelling up. My yard gets so soft it feels almost uncomfortably soft, like I might turn an ankle. It is dune sand soft but held together with the grass and roots.

That's my take on aeration. I've never seen anyone bold enough to agree with me out loud, but I have seen reports of people using my method and getting the same softness results I...

dchall, you mention being familiar with Apple Valley and Edwards. Military experience? Just curious.

As far as the exposed dirt under the pad...don't till it, but just place mulch on it? And will this do enough that grass seeds planted afterwards will "take"? Not saying I disagree, just never thought of that before.

You also suggest planting grass in June, suggesting that soil temperatures will be high enough then. I don't know how soil temperature relates to temperature in general, but we push near 70 in the day right now and it gets near freezing at night. June seems to me like it would be way too hot, we're near 100 by that point. But like I said, I'm not sure how soil temperature is affected.

Thanks for the takes on aeration (bpgreen and dchall). So much more to this all than putting a seed into the ground and putting water on it.

do your neighbors have subsurface drip irrigation systems? Apparently, with SDI, if you do rototill in amendments, make sure to re-compact the soil nice and firm afterwards. If the soil is too loose and well draining, the SDI system might not work very well. Check out this link, about a third of the way down the page:

http://www.jstryker.com/goofing/houselandscape/index.htm

quote: "subsurface system on the lawn has been a disappointment. My lawn has had numerous dry spots that developed shortly after the sod was installed, and I have been unable to eliminate them by adjusting the water run times... I had used a similar product on commercial systems several years ago with success, so the problem is specific to my situation. It appears the problem is due to a combination of porous soil and insufficient soil compaction. The idea of the subsurface drip is that the water comes out of the emitters (holes) on the tubes and then it moves through the soil, by capillary action, up and sideways to wet the entire area. However the soil in my yard is very porous and was dug up to remove roots, so it was very loose. As previously noted we rototilled the soil to remix it and put a lot of organic amendments into it. After we aerated the soil we then compacted it to industry standards using a water-filled roller. We then installed the sod and compacted it again using the weighted roller. Unfortunately, while this is the normal procedure for installation of a new lawn, this apparently was not sufficient on our very porous soil to create enough contact between the soil particles to allow the water to move by capillary action....

....the water is going straight down in the soil and only wetting the area directly below the tubes. I believe this is because the soil needs to be compacted a lot more firmly when using the subsurface system than occurs when using the standard weighted roller compaction method I used.... The lesson learned is that the subsurface drip system does not work well in porous, well-draining soils, and if it is to be used in a well drained soil it is important to over-compact the soil....

....If your soil is less porous, then the subsurface drip system can work well. I have used it successfully on lawns in several locations, but in all those cases the soil was compacted using heavy tractor mounted compaction equipment."

does your neighbors bermuda stay green year round or does it go dormant in winter?

there was a thread about soil temperatures here:

http://forums2.gardenweb.com/forums/load/lawns/msg081518585642.html?7

Warm Season Grasses
120F Shoot growth ceases.
110F Root growth ceases.
80-90F Optimum shoot growth.
75-85F Optimum root growth.
74F Optimum time to overseed bermudagrass with ryegrass in the fall. Time to plant grasses in the spring.
64F Expected spring root decline is triggered and roots turn brown and die within 1 or 2 days.
50F Root growth begins to slow below this temperature.
50F Chilling injury resulting in discoloration is possible.
50F Initiation of dormancy occurs resulting in discoloration.
25F Low temperature kill possible.

I won't belabor this, but since no one else is mentioning it, I'll say again that if I were you, I would do nothing else before getting a soil analysis. And you should never put sulphur down unless you've documented that the soil is indeed too alkaline.

The condition of the soil beneath the old concrete is anyone's guess, and I'd guess the remainder of the yard hasn't been getting what it needs for quite a while.

My approach would be:

1. Soil analysis, ideally one from under the old concrete pad, and one from the remainder of the yard.

2. Start killing the current vegetation from the areas where you want to have lawn, because it might take a while.

3. Irrigation system

4. Soil amendments, based upon soil analysis, and till into the top 3 inches of the area under the old concrete pad

5. Seed

But it's a free country. Best of luck.

angus37 asked,
dchall, you mention being familiar with Apple Valley and Edwards. Military experience? Just curious.

Yes and no. Back when the space program was building and breaking the sound barrier was a new thing, Apple Valley land seemed like a good investment (we lived in Riverside). This was long before Roy Rogers moved there. Unfortunately the space program abandoned Edwards, so it wasn't until after Rogers moved in that the land value really started to go up. But yes, my father and I were in the air force. Neither of us was stationed at Edwards but we visited there many times. I've never been to Palmdale or Ridgecrest except to drive through on the way north.

I'm going to bump this thread because I've been hard at work in other yard projects but am coming back to the lawn issue.

I have removed the junipers and their stumps. While doing this I found a power line and removed this. I have also finished removing the sprinkler pipe in the yard. As a result, my yard is covered with holes and trenches from all of these removals.

I'm not trying to be stubborn about this, but at this point, with the yard in such disarray, could someone please tell me why I should NOT rototill the whole thing? I feel like I've already torn half of it up, might as well finish.

If I rototill, my plan is to go over it all to smooth it out, either with a rake or a roller (I think someone mentioned a section of chain-link fence too, good idea). But I am worried about tree roots, both from the junipers and the mulberry trees on the other side of the yard. Roots and rototillers don't exactly get along; any suggestions on how to get rid of the bigger roots?

The real tool to use is a tractor with a box blade on the back. The box blade has ripper tines that can pull roots, wires, and sprinkler systems up quickly. You might have to pull down some (wooden) fence to get a tractor in, but it's done all the time. If you can't get a tractor in, then go for it with the rototiller.

If you are going to till (and I can tell you are), till in every compass point direction you can find. The goal is to get it tilled evenly to an even fluffiness and depth. That is impossible to achieve but by going over and over it you can approximate the effect. The problem is that tillers will encounter big roots and other hard things. When they do they will ride up over and not till to the same depth everywhere. So you will have very fluffy soil for 12 inches deep in some areas but only for 6 inches in others. When the soil finally settles in 3 years, what used to be 12 inches of fluff will now be 6 inches lower when packed. The stuff that was 6 inches deep will only be 3 inches lower. I think you see where I'm going with this. At the end of three years you will be very disappointed with your back yard. That can be fixed but just know to expect it now so you are somewhat less disappointed in 2012.

I would till and add some new screened soil to the are where the concrete was. I learned the hard way after taking a 20x20 concrete pad out a few years ago and by late July the entire area was brown and needed waterd LONG to come back. The soil was very compacted after years of concrete on top.

If I were to do it again today, I would till it deep, add a few yards of good, clean soil, add organic material and starter fertilizer and a good seed, watering regular.

I usually find very little to disagree with Dchall on, but, the experience I had with rototilling a yard was different than what he anticipates.

It was a front yard that had clay soil. As David suggests, a utility tractor with a rear tine powered tilling unit was used.

It was done well and deep. My recollection is 10 to 12 inches.

It will be soft when you seed, sprig or whatever. The key is to stay off of it as much as possible until it settles and firms some. When it is wet it will still be soft for probably the first year. But, mine firmed up and after three years was as level as any other yard.

There are many good ways to skin a cat when it comes to yards, but with all the excavations you've already done, and with the condition of what little grass you have left not being too good, I'd just rototill the whole thing and get it all loose, even and level and start the next batch of grass from that. Also, it is a great time to til in all the compost/organic matter you can afford.

rcnaylor,
That's good information, Richard. I would suggest the key to your success was that the tiller was tractor powered. That means the wheels were planted firmly on something while the roto blades spun independently. Most people rototill with a self powered device that rocks and rolls around the yard giving the operator quite a workout. The problem comes when it sinks into the soil it is tilling leading the tines to dig in deeper in front than where the tiller is sitting. The impossibility of holding one of those things to a fixed depth is what leads to the problem.

I wouldn't argue with that at all, David. And, having used one of that kind last summer with a son-in-law, you are very right that depth is very erratic with those kind. Our problem was moisture. Where it was a little moist it would til deeply. Where it was dry, it was hard to get it nearly as deep.

I made multiple passes and then levelled it up some more by hand. But, evenness on that one certainly wasn't anything to write home about by the end of the year.

Like most yard jobs, there is always something for us lawn whackos to worry about. ;)