# Pre overseed soil report



## SIUCpilot (Aug 5, 2021)

Hello,

I am approximately 2 weeks out from core aeration, dethatch, overseeding and topdressing with compost. Lawn is 8.5M TTTF in zone 5b with clay soil. Here is my soil report…..



and my saturated paste report…….



Thoughts?


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## Virginiagal (Apr 24, 2017)

No one has responded. I think this is one for @Ridgerunner, if he's available.

A remarkable CEC (good thing), high PH with low calcium (strange), very high magnesium (why is the magnesium so high?), organic matter is unusually high.

I have no knowledge about saturated paste tests so can't comment on that. From the soil test, it looks like you need some phosphorus (aim for 228 lb/ac as a target). Definitely do not add any kind of lime. The soil test is calculating a deficit in calcium and phosphorus but Logan is trying to get nutrients to fit into their "optimal" ratios, which is unnecessary. You can instead compare to SLAN values. When reporting 6 inches of soil, which you did, ppm is half of lb/ac. I'm linking to a thread on interpreting Logan tests:
https://thelawnforum.com/viewtopic.php?t=60


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## SIUCpilot (Aug 5, 2021)

MAGNESIUM - I had applied magnesium sulfate prior in the year in an attempt to bring up a low magnesium level from last year. I either overapplied, or it hasnt worked its way down through the soil profile enough yet and, is reading high

PH - when I bought the house a few years ago the previous owner had applied lime due to what he claimed was "low PH". I am guessing he overapplied and took the ph too high?

ORGANIC MATTER - there have been a couple of topdresses of compost and peat following core aeration. Additionally, I apply LARGE amounts of milorganite liberally and often, in addition to spreading biochar and spraying humics


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## Ridgerunner (May 16, 2017)

I'm afraid I'm not going to be able to contribute much.
There just isn't much useful data in the report. Logan used M3 to extract nutrients and the more pH is above 7, the more skewed and unreliable the reported results are. It would be a crap shoot to make recommendations based on the data.
There is also some reported data that wouldn't be expected. For example, even though M3 can inflate Ca and Mg results, you wouldn't expect Ca availability to be deficient in a high pH soil. However the saturated paste test (which measures what is available at the time the sample was taken) shows Ca at 17 ppm. The desired range is 40-60 ppm. Excess bicarbonate could tie up calcium, but although your bicarb levels are elevated (above the ideal of <50 ppm) they are below 100 where bicarb is normally expected to only start having some detrimental affects. Also when bicarb ties up Ca, it will usually free up P, but the saturated paste levels for P are less than .03 (ideally it should be 1-3 ppm). Consequently, I don't have a guess what is going on with Ca. 
Saturated paste test results are only a snapshot for the time the sample was taken and aren't necessarily conclusive of the overall ability of the soil to supply nutrients; however, in this case, with the exception of Mg and Fe, your nutrient levels are all very low. One would almost expect this soil to be barren (I'm guessing that's not the case-how does your lawn look?), but even though M3 skews some results, based on the soil report results, I still wouldn't expect nutrients to be at the reported saturated paste levels. 
Whether due to sampling error (due to all of the amending over the last couple of years) or lab error, my gut feeling is these results are not useful for making adjustments. I would suggest you apply nothing but N and 1-2 pounds of P2O5 during the remainder of this year. Retest using an ammonium acetate extract for the major nutrients and the Olsen test for P next Spring before you add anything to the soil and go from there.


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## Ridgerunner (May 16, 2017)

I do have one outside guess. It is possible that the P from the LARGE amounts of Milo applied could be tying up solution nutrients to produce a low saturated paste level contrary to what would be expected from the soil test levels. So maybe don't add any more P for the rest of the season-just N.


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## SIUCpilot (Aug 5, 2021)

Sampling error is doubtful, as I took 15 cores from various areas and sent in 2 cups of the mix. Logan keeps samples for four weeks, so I will email and have them add those tests. Thanks!

Dave


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