Iowa Soil Test Results Help - Year 2

5 years ago

Looking for 2017 advice please. Last fall I followed morpheuspa's fall recommendations. I did not apply the starter fert or milorganite this spring. Two pre-m applications were applied with the second containing nitrogen this spring. Coffee grounds have been dumped around the yard.

The increase in PH is interesting. The sod is almost 2 years old now and does get irrigated. I was able to get this information on the water.

- Water Hardness - Average 7.5 - 8.5 grains per gallon

- Water PH posted by Treatment Plant - 9.44

I did combine the two samples from 2016 per morpheuspa's suggestion. Thanks for any suggestions.

Last year link: http://forums2.gardenweb.com/discussions/4013101/iowa-soil-test-help?n=6

morpheuspa's fall Recommendations:

August 15: (optional but recommended) Apply 4 tablespoons of 20 Mule Team Borax per thousand square feet in Milorganite carrier.

September 1: Apply starter fertilizer at the bag rate.

September 15: (optional but recommended) Apply 3 pounds per thousand square feet of potassium sulfate.

October 1: Apply starter fertilizer at the bag rate.

October 15: (optional but recommended) Apply 3 pounds per thousand square feet of potassium sulfate.

2017 - Report

2016 - Report

Featured Answer

beckyinrichmond

5 years ago

Your phosphorus and potassium levels are fine according to SLAN targets. Your higher pH is probably related to the high pH irrigation water. Your sodium level is a bit higher than last year too. But there's not much you can do about the water supplied to you. The main problems alkaline soils have is that phosphorus tends to get bound up with calcium and then is unavailable to the plant. Using organic phosphorus, as in Milorganite, provides a slow release of nutrients so there is more chance for the grass to get some before it gets bound up. The other problem alkaline soils have is iron is less available. Here too Milorganite helps save the day, as it provides chelated iron which is more available to the grass. So keep using Milorganite. When you use it at bag rate, you get 0.72 lb/k of nitrogen.

KBG likes 3-5 lb/k of nitrogen a year. Most should be applied in the fall. Milorganite needs active microbes, so when the soil is cold (later in the fall, early spring) it's not effective. The very late fall fertilizer application (after grass stops growing, before ground freezes) should be a synthetic fast release nitrogen. Don't apply more than 1 lb/k of nitrogen (or any nutrient) a month. To see how much nitrogen is in a fertilizer, divide the N number into 100. That gives you the rate to apply to get 1 lb/k of nitrogen. If ammonium sulphate is available, you could use that when you want to substitute a synthetic for Milorganite. It is the most acidifying nitrogen fertilizer. Don't expect any great reduction in pH, though. If you leave grass clippings on the lawn, you can reduce fertilizer by about 1/4.

Put some soil in a dish and add some vinegar. If it fizzes, ask for an ammonium acetate test for base cations next time you get a soil test. The Mehlich 3 extractant overcounts calcium in calcareous soil and that's why Morph didn't trust the CEC or calcium numbers.

Sort by:Oldest

Comments (14)

Wors
Original Author
5 years ago
Becky, thank you for the quick response and advice. I will continue with the Milorganite and look up synthetic ammonium sulfate fertilizers.

For the next soil sample I will use your vinegar test and ask for the ammonium acetate if needed.
Related Discussions
Got Soil Test Results...need help.
Q
Comments (2)
Based on backyard Ca and pH, maybe you did mix 2 up since you say you limed front yard and what you posted makes it look like back yard was limed. DO NOT put lime down again. The 6.3 is great and the 7 pushing high. Doing the lime was a mistake. If they aren't backwards, then liming was good because pH 6.3. If you did get the 2 mixed, it makes sense that P is getting locked up and Ca is higher. Me personally, I'd have to retest again now.
...See More
soil test results - need help w/ pH, lime %, and N
Q
Comments (5)
1) Is there any tangible benefit in lowering my pH from 7.2 to the recommended 6.5? I wouldn't bother trying unless you have plants that show signs of iron chlorosis (yellow leaves with green veins). In that case, I'd treat the individual plants using sulfur buried in the soil. 2) Do I need to do anything about my lime %? From what I've read, lime is added to raise the pH, which is going in the wrong direction for my soil. I find it more than a little odd that you'd have a low level of lime. I wonder if you have calcium in other forms. I would not do anything about that unless it's causing problems. As you noted, adding lime will exacerbate the pH situation. 3) It seems like I could bump up both my N and OM by adding a few bags of steer manure. Does anybody have any numbers on %N by weight, or lbs N per cu ft, for composted steer manure? N will always show up on soil tests as low, unless you've just fertilized. N just doesn't stick around long in the soil. Steer manure, particularly the bagged stuff, is more of an amendment than a fertilizer, so you won't be adding much N with that. One caution on using manure in the intermountain west is that it can have relatively high salt levels and salinity can be a problem here due to the low rainfall (same thing that contributes to the high pH). I'd add shredded leaves from any trees (unless you're mulch mowing them), coffee grounds from Starbucks (or other coffee shops, but Starbucks has a corporate policy of making them available for free to gardeners), shredded tree trimming (some tree services will supply them for free), and anything else you can get for free. Note that if you spread 3 cu yds per 1000 sq ft all at once, you'll smother the lawn. If you use tree leaves and/or shredded trees, either spread them on top, or, if you incorporate them into the soil, add a nitrogen source so they'll decompose readily and not make N unavailable to the plants. If you use coffee grounds, don't spread them in layers more than about 1/2 inch thick, because they can crust over and repel water when they dry. Coffee grounds are a source of nitrogen (about 2.5% nitrogen).
...See More
Iowa Soil Test Help
Q
Comments (6)
You can irrigate or not irrigate as it pleases you, although for this year I'd irrigate at least the lawn if possible. Your grass is young. After that, however you play it is up to you! This year, I'm not irrigating (except the gardens, of course). Overall, the test isn't bad. For the most part, I rolled the lawn and outlot together as they're very similar results. Where they differ in an important way, I was careful to note that. In the future, you can combine these tests. ME 20-something: Normally, this would speak to a heavier soil, but in your case the excessive calcium is pushing this answer up. I'm going to call your soil around an ME of 15, or what would usually be a pretty good loam. pH 7.1: A little high, but nothing that'll cause any problems. It will tend to limit iron uptake, so use of Milorganite is a good idea. Other than that, your grasses (and most plants) won't have too much trouble with this, although I'd avoid acid-loving plants in the gardens. Organic Matter 3, 4.5: Fair and Good, respectively, both of which are great given your ME. Certainly mulch mow, mow all your fall leaves, and feed organically if you wish, but you don't need to make any special effort. Sulfur 20, 9: Both are perfectly acceptable answers. The 9 might be a little low, but although sulfur is required, it's not required in huge amounts at any one time. That won't cause deficiency. Phosphorus 58, 81: Very close answers (for all they look different) and both rather low for this particular test. At a pH of 7.1, my target would be about 220. We use standard starter fertilizer to fix this, and just get the cheapest. They're all about the same. Recommendations below. Calcium 82%-ish: Very high, but not a problem. Calcium's not toxic under normal circumstances and lawns can grow in limestone chips. It's setting off your higher pH in part, but there's nothing we can really do about it anyway. Avoid major calcium sources. Magnesium 12%-ish: It looks textbook perfect, but it's actually rather high--it's just somewhat suppressed by the high Ca. Avoid magnesium sources. Potassium 0.8%-ish: It looks very low, but it isn't as low as it looks (the calcium and magnesium are both depressing this answer). Still, it is lower than I would like to see, optimally speaking. While technically optional, I'd do the following. We use potassium sulfate (sulfate of potash) to correct this, which you can sometimes get at garden or landscape stores, or have them order it for you. Or you can get it online. Recommendations below. Minor Elements: Boron is off in the Lawn area, and discussed below. Iron is also mentioned. Iron 100-ish: Absolutely not a problem, but not going to produce good color at your pH. Whenever you wish, apply Milorganite at the bag rate to very slowly raise this. Boron 0.32, 0.74: Optimal on the Outlot portion, low on the lawn. While not the most important element, I'll always work to move your lawn into the most optimal range on everything. Me? I'd fix this. 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. Recommendations: August 15: (optional but recommended) Apply 4 tablespoons of 20 Mule Team Borax per thousand square feet in Milorganite carrier. September 1: Apply starter fertilizer at the bag rate. September 15: (optional but recommended) Apply 3 pounds per thousand square feet of potassium sulfate. October 1: Apply starter fertilizer at the bag rate. October 15: (optional but recommended) Apply 3 pounds per thousand square feet of potassium sulfate. May 30, 2017: Apply starter fertilizer at the bag rate.
...See More
Soil Test Results - Help with soil management plan
Q
Comments (5)
According to my calculations, you are short about 2 lb/k of P2O5 (phosphorus) and 4 lb/k of K2O (potassium). Probably the easiest way to get that 4 lb/k of potassium is to use a balanced NPK fertilizer, like 10-10-10 or 20-20-20. It would also give you 4 lb/k of nitrogen and 4 lb/k of phosphorus. You don't need that much phosphorus but it won't harm anything (except possibly the mycorrhizae). You want to avoid nitrogen in the summer. So if you went with the balanced fertilizer, you would be applying probably 3 applications, one a month for mid August, September, October. The 4th could be next year. Divide the NPK number into 100 to get the application rate (example, for 10-10-10, divide 10 into 100 to get 10 lb/k rate). An alternative is to find SOP, potassium sulfate, 0-0-50. You could apply that once a month, even in the summer, at 2 lb/k for four months. That would take care of the potassium. Two applications of starter fertilizer in the fall would take care of the phosphorus. Since you're planning to overseed, it would make sense to use this plan, as you could do an application of starter fertilizer at seeding and another a month later. Milorganite could substitute for the second application of starter in the fall. Use bag rate for starter or 25 lb/k of Milorganite at 5-4-0 to get 1 lb/k of phosphorus. As for nitrogen, the balanced fertilizer plan would give you 4 lb/k, which is more than you need for the year considering that you have already applied nitrogen this spring. If you use the alternative plan (which I think is better), you would get almost a lb/k with each application of starter fertilizer (1.25 with Milorganite at 25 lb/k) and then you could do a winterizer application of a quick release nitrogen in late fall after the grass has stopped growing but before the ground freezes. That would get you off to a good start next spring, when you could hold off on fertilizer until around Memorial Day. Your organic matter is low. It's good to leave clippings on the lawn when you mow. This fall mulch mow any leaves in your neighborhood that you can gather. If this is new construction, there may not be many trees but do what you can. The compost you're planning will help. Mulch mowing leaves is like making your own compost for the lawn --and you don't have to spread it! Water in your applications. Milorganite does not need to be watered in. Phosphorus tends to get tied with quickly with calcium in alkaline soil. It's there, just not available to the grass. Using organic forms of phosphorus, like Milorganite, enables a slow release of phosphorus. If you test next year and phosphorus is low, it's probably because of the alkaline soil. It's still there, just unavailable. Such is life for alkaline soil.
...See More
beckyinrichmond
5 years ago
I wouldn't go out of my way to find ammonium sulfate. If I were at the store and there was one fertilizer with urea and another with ammonium sulfate and other things being equal (price for example), I'd pick the ammonium sulfate for an alkaline soil. If your soil is limestone based, it will say "Ha, ha, I'll neutralize any acid you throw at me." Decomposition of organic matter is acidic. Rain is acidic (about 5.6). Mulching leaves is good for many reasons, besides the acidifying you would get when the leaves decompose. Your irrigation water seems very alkaline. I wonder if your pH will vary depending on how much you have to irrigate. Many people grow great grass with alkaline soil, so don't worry too much about it.
dchall_san_antonio
5 years ago
I've never heard of water with that high a pH. Seems like you'd see signs of damage or discoloration on everything that gets wet. Does it render fat to make soap?
beckyinrichmond
5 years ago
I did a little reading. There is a difference between water with a high pH and alkaline water. The alkalinity of the water is a measure of its "liming effect" and has to do with what's in it like bicarbonates. Water with high pH isn't a problem but water with a lot of alkalinity can affect the soil. Maybe your water treatment company can tell you. It is measured in mg/l or ppm of CaCO3. Also, on ammonium sulfate, if you use it, be sure to follow instructions on the bag as it can burn the grass if applied improperly.
Wors
Original Author
5 years ago
L.D. McMullen is the treatment plant. The data is in the link below

http://www.dmww.com/water-quality/water-quality-data/
beckyinrichmond
5 years ago
I sent them an email to ask as that data is not on the webpage.
Wors
Original Author
5 years ago
Great, thanks for taking the time to help me understand.
beckyinrichmond
5 years ago
Here's the response: "CaCO3, calcium carbonate, concentration of McMullen Finished water yesterday was 80.12mg/L."

Now what does that mean? I know that mg/l is the same as ppm. But what does that say about how much the water is contributing to your alkaline soil? Maybe post a question on another thread. I know of a chemist on here but he may not be reading this thread. How much CaCO3 equivalent you're getting from the water would depend on how much water you apply. I wonder if there is a way to convert this to gallons. In any event, it is contributing something.
beckyinrichmond
5 years ago
Found something of interest: bicarbonates in irrigation water

One of the slides called Water Quality listed <40 as good, 90-120 as increasing problems, > 125 generally not suitable

So at least yours falls under the limit for "increasing problems." Keep in mind that Morph suspected you may have calcareous soil, meaning it's going to be alkaline no matter what.
danielj_2009
5 years ago
@becky: You can calculate the amount of CaCO3 applied to the lawn from the 80.12 mg/l figure, as you indicated. Multiply that figure by 3.79 to get 303 mg/gal. If you apply 1 inch of water to each 1000 sf, that comes out to 623 gallons. Multiply the two and convert to lb and you get 0.41 lb CaCO3/ksf of lawn. What's a typical % calcium carbonate for lime? Whatever it is divide it into the 0.41. Let's just say your water contributes about a pound of alkalinity as CaCO3 each time you water, so maybe not a big deal.

I think high pH water like yours can be neutralized in couple of days just by letting it sit in a container (not that you could do that). The CO2 in the atmosphere reacts and is enough to drop the pH a lot pretty easily. I imagine it's about a wash, so to speak between your water and rain/dew that will neutralize it.
danielj_2009
5 years ago
In addition to adding all the things becky mentioned in order to reduce pH and/or improve the soil tilth, you could add sawdust. Sounds odd, but it is supposed to be great for soil structure when it breaks down. Morpheus used to recommend this.

You don't want sawdust with anything like glues in it. The best thing is a product like Equine Pine, which is compressed sawdust pellets for horse stables. I got some at Tractor Supply one time for $5 per 50 lb bag. I put down a full 50 lb per ksf with my spreader opened wide up. It will quickly dissolve into the soil and a week later you won't even know it was there. It does take a long time to break down and you don't want to till it in as it will rob nitrogen from your grass. On the surface it will get the nitrogen it needs to break down from the air ... Just a thought. It's something you might add once or twice a year.
Wors thanked danielj_2009
Wors
Original Author
5 years ago
Thank you both for the information.

danielj, a local tractorsupply store sells pine pellets $5.79 for 40Lb bag. I will add the pine pellets to my plan.
beckyinrichmond
5 years ago
Your soil is buffered. A highly buffered soil will resist pH change. In a poorly buffered soil pH will bounce around anytime something is done to change pH. How buffered is yours? A CEC in the 20s would indicate highly buffered. Morph thought it was probably closer to 15, which is still fairly resistant to pH change but it can move. The ammonium acetate test next time will give a more accurate number. Daniel has given some good information on lowering the pH of your water by letting it sit around. Many herbicides break down in an alkaline water and should be mixed with a neutral or acidic water. Next time you need to mix up something, you could let the water sit around in shallow containers for a day or so and that will help lower the water's pH.

Iowa Soil Test Results Help - Year 2

beckyinrichmond

Comments (14)

Wors
Original Author

Related Discussions

beckyinrichmond

dchall_san_antonio

beckyinrichmond

Wors
Original Author

beckyinrichmond

Wors
Original Author

beckyinrichmond

beckyinrichmond

danielj_2009

danielj_2009

Wors
Original Author

beckyinrichmond

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

Iowa Soil Test Results Help - Year 2

Comments (14)

WorsOriginal Author

Related Discussions

WorsOriginal Author

WorsOriginal Author

WorsOriginal Author

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

Wors
Original Author

Wors
Original Author

Wors
Original Author

Wors
Original Author