Sorry for the delay here, we're in the middle of a rather severe blizzard. Hopefully this won't get cut off by a power outage during writing, but I'll save it off to a text file regularly just in case!

Overall: Not a bad first read in either case, and although there's some minor indication of differences in the yellow grass area, they're not extreme in any sense. Soil differences don't account for the yellow. Some of the soil numbers, however, aren't helping you here.

Exchange Capacity 9.3, 7.9: Probably sampling differences. In either case, this is most likely a sand/silt mix, around fifty-fifty. It's a nice soil overall, not too light to hold resources, not so heavy that it's hard to change.

pH 7.3, 7.1: Within sampling and test normal bands of error. Both are slighty alkaline, but neither are a barrier to a fantastic lawn. I grew a great lawn at 7.2 when I overshot.

OM 5.0, 3.9: Pretty much in the Good range. Not that I'd object to more OM, I never do, but it's not an emergency. Certainly mulch mow all your fall leaves, mulch mow your lawn, and maybe consider feeding organically if you want to.

Sulfur 11, 14: Normal for a higher pH soil, and not a problem.

Phosphorus 36, 62: This isn't helping color or quality, but shouldn't be an extreme hit on color. On quality? Absolutely this is costing you and going to cost you quality rather badly. Target here is 220 or so. Recommendations below. I use starter fertilizer, the cheapest you can find, to raise this.

Calcim 80-ish percent: High, but not outrageous, and certainly not going to cause you any problems. This is fortunate as you won't be able to get rid of this. Avoid any significant calcium source like lime or gypsum.

Magnesium 14.5%, 10.6%: In perfect range on both--that minor shortage on the green lawn isn't really much of a shortage, and not worth doing anything about at this time.

Potassium 2.3%, 2.9%: Technically OK, but the numbers are a little low. K adds to weather tolerance, which influences color a bit during winter and the hottest part of summer. We use potassium sulfate to enhance this, which you can usually have garden stores or landscape stores order for you. It's rarely available off the shelf. Recommendations below.

Minor elements: Boron is very low, which can produce color issues in some cases. I also discuss manganese and iron below.

Boron 0.23/<0.2: Deficient. We use Milorganite as a carrier and 20 Mule Team Borax as the boron source. You can purchase 20 Mules at the grocery store in the laundry section. In a wheelbarrow or the like, dump the Milo. Spraying very, very lightly with water (I use a spray bottle like the kind people use to damp their clothes when they iron) will help the boron stick. Add the recommended amount of 20 Mule Team Borax and stir, spraying occasionally to get the stuff to stick to the Milo. Then apply over the recommended area. So if going for bag rate Milorganite (1 bag per 2,500 square feet), you'd add 10 tablespoons of 20 Mule Team Borax.

Iron/Manganese: Your iron numbers are technically OK, but manganese is very high. Fe and Mn are antagonists, which means the manganese fights the iron. Since iron is used to produce chlorophyll, which produces the green color of the lawn, this is a potential problem. Whenever you like, apply Milorganite at bag rate to slowly raise the iron levels. Color tends to improve when iron significantly exceeds manganese.

Recommendations:

April 1, 2016: Apply 2 pounds per thousand sq ft of potassium sulfate. Apply 4 tablespoons (not a misprint and don't get this wrong) of 20 Mule Team Borax per thousand square feet.

April 25 or so, 2016: If you can get triple superphosphate, I might use that at 2 pounds per thousand square feet to avoid feeding nitrogen to the lawn (it doesn't want it yet). However, if not, the problem is severe enough that I'll recommend starter fertilizer at bag rate instead. You need P far more than you need to avoid N.

Memorial Day 2016: Apply starter fertilizer at bag rate.

Labor Day: Apply starter fertilizer at bag rate.

September 15: Apply 2 pounds per thousand sq ft of potassium sulfate.

October 1: Apply starter fertilizer at bag rate.

I'm not sure whether the soil is that thin under all the yellow areas in the lawn, but it's something I'd like to find out when the snow melts. The yellowing actually didn't seem to start until the fall, maybe around October. It was pretty gradual at first though - strips of lighter green that eventually become mostly yellow. If you look at the photos in my previous post, you'll see that the rear part of the neighbor's yard is all yellow.

I'm glad to hear that you've been able to achieve a green lawn with alkaline soil. Do you do anything special, like sulfur treatments or other alternatives?

Morpheus - Thanks so much for taking the time to analyze our soil test results and give recommends...and in a blizzard no less!

I'll review your comments with my husband and get back to you with any questions. In the meantime, are you thinking that the high manganese might be causing the yellowing by preventing the grass from taking in iron?

It absolutely doesn't help. I also had this exact issue (and with almost exactly those numbers!) You've seen the modern shots, the lawn is deep, dark green--but I've sent the iron through the roof over the years. Initially, the grass color was unimpressive.

You can't get rid of the Mn, which isn't a problem. It's not toxic at these levels and your lawn will do fine. So we raise the iron instead--which isn't toxic until levels that are absolutely impossible to achieve or maintain. Grasses do fine in soils with 50,000 PPM iron as long as the pH is normal or higher.

Alkaline soils (yours isn't, 7.2 average is effectively neutral) are really difficult to change; soil-applied sulfur is ineffective. It can be done by using acidifying fertilizers, like ferrous sulfate (for iron only), ammonium sulfate, and the like. Even urea-based sources will slowly acidify a soil.

That works if you don't have limestone bits in the soil. At your pH, I doubt you do in any significant number.

But it's also unnecessary. Lawns do quite well up to 7.5 easily, and with some work right up to 8.0. You just balance the soil resources to account for decreased availability of some elements and increased availability of others. I already did that with your phosphorus levels, targeting them higher than I would on my own lawn (currently pH 6.3).

Morpheus -- a question or two if I may... Are the iron numbers reported by Logan reported as available iron (at the given pH) or total iron (I'm assuming total)? Do you target iron levels assuming the lawn is going to get into the proper pH level due to other changes you recommend? I'm assuming it is pointless to raise iron for lawns above 7.5 pH, as you say, because it wouldn't be available anyway.

Central and South Texas was once a sea bed and is now about 1,000 feet deep with ancient seashells. Over the years rains have dissolved them into relatively pure limestone with a pH around 8.0. It is not hard at all to grow grass in this soil. Keeping it dark green sometimes is a challenge. Notably the lawns become yellow after several days of a steady rain. The soil surface can become slightly more acidic by plant and microbial activity, but when it rains that acidity seems to be flushed away. When that happens the iron binds to the calcium causing the grass to yellow. Over the winter the soil recovers and the grass is green again in the spring. Adding sulfur is a lost cause, especially for us in Texas, because we would have to dissolve all the limestone with sulfuric acid before we could make a permanent change. It will be interesting to see if your yellow grass looks greener as spring takes effect (early April).

Regarding boron: read carefully what morph said about it. Boron is one of those micronutrients every creature needs but at a certain level it suddenly becomes toxic. This is definitely not morph's first time recommending the addition of boron, so he knows how to make it work with the least amount of hassle.

Regarding Milorganite: on the other hand, I don't think there is a limit to how much of this product you can apply. Morph did try a few years ago to overdose and cause a problem, but short of smothering the grass with it, it seems to do nothing but make things better. Long before you smother the lawn you will by chased away by the, uh, aroma, when it becomes wet.

Regarding iron/manganese: Metal ions in the soil, including sodium, calcium, magnesium, and potassium, are a balancing act. If you are blessed with an overabundance of one, often the only way to make things normal is to raise the values of the rest of the ions.

Regarding timing: don't get jumpy this spring. You'll see lots of advertising for fertilizers and seed in the coming weeks. Fertilizing early leads to resource depletion by late April. If you can wait until May to fertilize, the grass will have gone through the initial spring flush of new growth in a natural cycle without abnormal depletion. Then by adding nitrogen after that the grass will be prepared for summer.

Regarding organic fertilizer: Whether you use organic fertilizer (like Milorganite, soybean meal, alfalfa pellets, corn meal, or cottonseed meal) or chemical fertilizer (like Scott's, Vigoro, or other brands) is up to you. Most of the lawn nuts on the forums lean heavily toward 95% plus organic. The exceptions are the very serious bermuda lawn nuts who tend to be 100% chemical. If you decide to go with a chemical program, please consider at least once a year, adding some organic fertilizer. Many if not most of the lawn nuts have found themselves in a situation where adding a normal dose of chemical fertilizer did nothing. Adding more did help temporarily, but then it didn't. What was happening was the beneficial soil microbes necessary to process plant waste and chemicals were becoming weak and depleted. Once you apply an organic fertilizer the soil microbes come back to life and you can go all the way back to normal fertilizing. If you maintain a full organic program, you should never see this see-saw effect. If you'd like to talk more about organic lawn care, it's not that hard, certainly not expensive, and gives excellent greening.

>>Morpheus -- a question or two if I may... Are the iron numbers reported by Logan reported as available iron (at the given pH) or total iron (I'm assuming total)?

The total, which in Logan's case seems to include available, immobile, and some of the completely locked stuff. Any of the three, in any combination, could theoretically be reported by a given test (although available plus locked is a trick I'd like to see!)

>>Do you target iron levels assuming the lawn is going to get into the proper pH level due to other changes you recommend?

Not necessarily! In this case, I'm assuming the pH is fairly stable and won't be going much under 6.8 in any time period where I'm going to be concerned about it--and more likely to stay in the 7.0 range.

I didn't quote a target number because I'm not sure in this case...but I strongly doubt that a good, stable point will be under 250. How far it goes above that depends on the grass' genetics, and user preferences. Mine's around 300 and I'm just barely happy with that.

>>I'm assuming it is pointless to raise iron for lawns above 7.5 pH, as you say, because it wouldn't be available anyway.

Some is always available, but amounts drop quickly with rising pH. I'd be more likely to raise it and hope for the best, noting that the grass gets a shot at the iron as it goes by (at minimum). At pH that high on a grass that requires iron and isn't as tolerant of that pH, I'd probably recommend spraying iron instead when necessary.

You've fixated on the pH for some reason and I think the problem is simpler than that. You just installed the sod in August, the grass got ripped out of the ground from where it used to grow, got rolled up, transported to a totally new location with totally different soil. Got put on a different fertilizer program than what it was used to. Hopefully it rooted deep enough before it got hit with the cold. I think the grass is doing what every plant undergoing stressful conditions would do, which is yellow. A few months of spring time and it will whip into shape. Then you can start fine-tuning with soil test.

Thanks everyone for your comments!

@morpheus - We really appreciate your expertise. A few more questions when you have time:

* You said you targeted our phosphorus level higher than your own lawn. Is this due to the pH difference or something else? Is phosphorus bound in the soil at higher pH's, and is our pH (7.1 - 7.3) high enough to cause that?

* What kind of quality issues can we expect from the low phosphorus level until it's corrected?

* It sounds like the Milorganite is great stuff, but I'm very sensitive to odors, so I don't think it's a good fit for our lawn. If we used ferrous sulfate instead (being careful to sweep it off the concrete), what rate and frequency would you recommend? I assume we don't need to worry about lowering the soil pH too much with the ferrous sulfate since the starting pH is above 7.0.

@dchall - Thanks for sharing your experience - it's very helpful. At least for now, we're planning to stick with a chemical program, but I can see the advantage of applying at least one organic treatment per year. As I mentioned above, I'm super sensitive to odors, so I'm leaning away from Milorganite. Is there one organic treatment that you feel would be most beneficial when applied annually - one that doesn't give off a strong odor?

@j4c11 - Thanks for your thoughts. I originally "fixated" on the pH because the local extension agent thought that might be triggering iron chlorosis/yellowing. All the local experts I've consulted are surprised that our soil is slightly alkaline since apparently most people have acidic soil in this area and apply lime on a regular basis. There are other new homes in this neighborhood where the sod was installed around the same time, but they don't have the patchy yellowing that we do, so we assumed there was an issue beyond what you'd expect with a newly sodded lawn. Regardless of what the issue is, I'm sure the lawn will improve as it matures.

Thanks again!!

Spotty higher pH can happen if you got the soil off of one particular section of the pile...that happened to contain the old B horizon with some limestone in it! In my case, I got the old subsoil on my lot, so it just kind of stank all around.

* You said you targeted our phosphorus level higher than your own lawn. Is this due to the pH difference or something else? Is phosphorus bound in the soil at higher pH's, and is our pH (7.1 - 7.3) high enough to cause that?

pH. If you look at the availability of P by pH, it drops as pH rises above seven. You're not that far over, the binding isn't extreme, so I just boosted the numbers a little bit. Your standard is around 220, most people with slightly acidic pH would be around 200. In your case, I wouldn't blink at anything between 200 and 300.

I never use my own soil as a standard, per se, for anybody else's. Mine have given in to some experimental stuff, plus I've over-enhanced the gardens to match the (extreme) density and (extraordinarily high) performance I demand they support. My current P levels in the garden push 1,000.

* What kind of quality issues can we expect from the low phosphorus level until it's corrected?

Thin, weak, sparse growth that gets sick and dies easily, discolors easily, grows poorly, and generally doesn't look at all good. Installed sod would tend to thin out and die back over the course of a year or so if it isn't corrected, resulting in a lot of thin patches and blank areas.

N, P, and K are the big three and absolutely have to be there in the correct proportions (N we take care of on an as-needed basis).

* It sounds like the Milorganite is great stuff, but I'm very sensitive to odors, so I don't think it's a good fit for our lawn. If we used ferrous sulfate instead (being careful to sweep it off the concrete), what rate and frequency would you recommend? I assume we don't need to worry about lowering the soil pH too much with the ferrous sulfate since the starting pH is above 7.0.

I'd be comfortable with ferrous sulfate (monohydrate or pentahydrate, it doesn't matter) at 3 pounds per thousand square feet in April, early October, and perhaps early November if the weather's holding. Keep an eye on the pH in this case, though, as iron sulfate is about an eighth as acidifying as pure elemental sulfur and does NOT require digging in to work!

Never use iron during hotter months or when the soil's going to freeze solid for winter within two or three weeks of use.

Any of the organic products are good to use if you start small and work your way up. For example if you start with 5 pounds per 1,000 square feet that will feed the microbes so they can repopulate the soil. A normal application might be 20 pounds per 1,000, but if the beneficial microbes aren't there in sufficient population to decompose it, then the smelly microbes will come in to hurry the job along. It's the decomposition of protein in the organic materials that gives off an ammonia smell if it happens too fast. It is the smell of milk starting to turn sour. At least it's not the odor of manure or rotting fish!! Once you use something at 5 pounds per 1,000, then you should be able to go up to double or triple that amount after 3 weeks. The 3 week period is what it takes to bring up the microbial population, not the time it takes before the danger of adding more fertilizer is gone. Organics don't work the same as chemical fertilizers, so there is never any danger to the grass if you use too much or use it too often. The worst consequence is the aroma of milk.

angela -- you might consider going to Home Depot and smelling a bag of milorganite. I think people here are exaggerating the odor, including any "decay" odors. If you put it down at the recommended rate, 1 bag per 2500 sf, I'd be very surprised if you could ever tell it was there. It'd be a shame to avoid such a great product for fear of a slight "perfumy" odor. Don't worry, your yard won't smell like a landfill! :o)

One thing dchall said, just not to be confused by: You can't hurt your lawn with too much milorganite, but if you dump a handful on the lawn or out the spreader by accident, it will burn the lawn in that spot if you don't spread it out.

That, too. It can get a mite swampy if the weather turns wet and stays there...but even that disappears in a week, and it tens to happen only when applied at pretty high rates.

I use soybean meal, and can't smell it decay. There's a slight (pleasant) nutty odor when putting it down, though.

I would skip the organic dogma (if you can call cooked sewer sludge bacteria organic - where does that ever occur naturally?) and fertilize normally. Mulch mow your grass, mulch mow your leaves into your lawn in the fall, and you're all set. Do another soil test next year and if you're low on organic matter, then add some, if not, keep doing what you're doing.

I'll try to not get too deep into the organic doo-doo, so to speak, in reply to j4. The sewer sludge he's referring to is Milorganite. It's made by partially processing Milwaukee's raw sewage into something called class 2 sewage. It's wet and very smelly after anerobic bacteria work on it. The Milorganite people then dry that sludge in a kiln, break it into pieces, and bag it. I would compare it more to jerky than something cooked like turkey. The Milorganite product used to happen in nature all the time before sewage was processed or where it wasn't dumped into a river. If the sewage dried up before it could be processed microbially, then a natural form of Milorganite formed.

This is not to convince you what to fertilize with, I'm just explaining what Milorganite is. It's dried product made from partially decomposed sewage. Milorganite is not the only organic fertilizer, but it is one in a class of sewage products like Hou-actinite, Dillo Dirt, Alamo Gro, and several other sewage based organic fertilizers. My preference is to use ground grains for my fertilizer.

I really appreciate the additional information about the application of ferrous sulfate, plus the detailed explanation about the potential issues from low phosphorus. I noticed that a neighbor around the corner with an established lawn (about 2 years old) had some bare patches in his back yard, and I assumed it was from the dogs. Now I wonder if it might be the low phosphorus in the soil!

The information on Milorganite and other organics is great too. I'm sure the smell of Milorganite isn't THAT bad, but my sensitive nose tends to pick up on odors that no one else notices! I'm sure we'll do some experimenting over time to see what works best for our lawn.

You've all been so helpful - thanks so much for taking the time to answer my questions!