Rager, Like several MistaScott, I thought you were using "concrete" as a metaphor for really hard soil. Which seems appropriate for some sandy clay soils, like mine. How did you resolve your issue? Did you core aerate and topdress with a sand peat mixture? if so, did the lawn come back lush and green? In some locations, my Saint Augustine is perpetually yellow and thin. i suspect there is not enough permeability to facilitate deep rooting. If I run the sprinkler too long the water goes into the street. So, I run the sprinkler more frequently, and the stressed lawn develops fungal problems. These patches oscillate between severe dryness and mold issues, because the clay soil is impermeable to water, and fails to retain moisture. That area of the lawn is like a hydroponics operation. I have attempted the baby shampoo approach, using an Ortho Spreader, a cup of beer, some milk and J&J Baby Shampoo (Laurel Sulfate). I figured I could feed bacteria, combat the fungal issues, and break down the clay in one fell swoop. Let's see if the shampoo hype is more than just hype. Ultimately, I have littel faith. I suspect i will need to import viable soil to amend these patches of hardened clay. I will need to core these spots and topdress with a soil to prevent the clay from rendering the cores impermeable. The holes will trap water and fertilizer becoming the Normandy beach of my grass invasion. Any advice on what soil mixture to use on compacted Houston clay? And no . . . I'm not really invading Normandy.

piedmontnc summed things up rather nicely but I'll just chime in with this: When testing something, isn't it counter-intuitive to introduce additional ingredients? : Actually, the majority of lab work is done by adding other ingredients. As we've been discussing, a deflocculating agent is added for the textural analysis. In regards to the chemistry portion, the lab has to knock stuff off of the surface of soil particles so that they can be measured by machines, which is done by adding a lot of different stuff, depending on your needs. Sometimes it's an acid, sometimes it's a chelating agent, sometimes is bicarbonate, sometimes it's a cocktail of reagents,etc. Many times, something is detected and measured through a titration in which you keep adding a chemical to a solution until you get the expected reaction and the amount of the chemical that you used tells you how much of the thing you are looking for is in the solution. Lab work is all about adding stuff to what you're testing. Arsenic - strikes me as ubiquitous from the get-go. Yes, it is. How much is too much? That's the sixty-four thousand dollar question and the answer depends on a number of factors. Are you concerned with human exposure to the soil? Plant toxicity? Toxicity to you due to uptake of arsenic by the plants? Ground water contamination? All of the above? Because they will all have different thresholds. Then the answers depend on a whole slew of things including, but not limited to, depth to the water table, soil texture, organic percent, soil pH, the form that the arsenic is in, what you're growing and on and on. Again, I don't think that every time someone uses ironite an angel cries or anything. I just think that there is an, as yet to be determined, potential for crossing one of those thresholds. When there are other options available, I tend to take the cautious route. That's just how I roll. kimmsr and since the professor of soil science I long ago got this simple test from stated that nothing exceopt the soil and water needed to be added to get a good result I've met some brilliant soil science professors, some that pretty much know what they're talking about and some that I have an urge to call after every good rain just to make sure they didn't drown while looking up to see what was falling on them. Don't be too star struck by the title "professor". I see no reason to add anything to flocculate or hold in suppension I know ya don't, buddy. I know ya don't.

The county yard waste facility does not separate leaves from branches. I *could* get the leaves from them. But it would be at least 50% coarse wood chips, which are worse than useless since they both use nitrogen as they decay AND hold even larger air spaces in the soil than the unadulterated sand. They don't even call the stuff compost. They call it mulch and mulching paths is all its good for. The pine straw that I have in great abundance is far superior as a mulch for trees and landscape plantings and even in parts of the garden. But its just as useless as a soil amendment since resinous, 8-12-inch pine needles don't decompose any faster than coarse wood chips. When I lived in Massachusetts I had leaves in overwhelming abundance and they worked splendidly in the sandy soil (technically unsorted glacial till), I had there. This sand here is far different geologically being closer to washed-quartz play-sand than to the richer glacial till, ecologically with few deciduous trees, and climatologically with months on end of hot, humid weather burns organic material out of the soil with tremendous speed -- after 3 months I can barely detect any difference between the sections of garden where DH tilled in an inch of compost (all we had), and the fresh areas. Which is why I was inquiring about adding clay via cat litter because what worked in other places I've lived is either unavailable or less effective here. :-)

Dear dor476 - Maybe erect a "silent" fence for the dobies, and start researching plants for groundcover and erosion control, such as: Where there is Sun: Groundcovers: Cerastium tomentosum (Snow-in-Summer) Vinca Artemesia (Dusty Miller) short grasses like Festuca (Blue Fescue) shorter ground-hugging Sedums, ground Phlox, and Ajuga Veronica repens Lamium sp. (in shade) Alyssum saxatile ("Basket of Gold") Low Âgrowing Botanical Tulips: Tardiva, etc. Larger plants for anchoring the eye and the are: Panicum (grasses) Solidago (Goldenrod) Rudbeckia (Black-eyed Susan) Yucca Hemerocallis (in a "ribbon") Small trees, shrubs, and evergreens such as: Ilex glabra ÂnigraÂ(Inkberry) Bayberry Rugosa Roses Juniper (Juniperus noris ÂLime GlowÂ) Crambe maritima (Sea Kale) Pinus thunbergiana (Japanese Black Pine) Pinus nigra (Austrian Black Pine) Sumac, Rhus ÂLow Gro Hydrangea arborescens. This Hydrangea has a suckering habit (good for erosion control), and 5-6" flower panicles, but itÂs hard to find in the trade. Plants that are tolerant of drought: Salvia officinalis ÂRachelÂs Gold & ÂPagona Dianthus ÂBrilliant Star Zebrinus ÂLittle Zebra Potentilla ÂPimento Rosa ÂKnockout Sedum ÂAutumn Spire Knautia ÂMorris Midget Hope this helps, as all or most of these will live in your zone. Best, PP