# Soil sample location question



## Ryan1+2 (Oct 16, 2018)

I have a question about whether two locations should be treated separately or mixed together and tested the same. Basically in the fall I did a complete Reno on my side yard and backyard which are separated by a driveway. I applied the same amount of lime and fertilizer to both and seeded both at the same time. Should I sample each of those locations separately since the driveway divides them or treat them has one sample since I treated them both the same in the fall ? This fall I plan on renovating my front yard (has alot of moss) which I will definitely be sampling and testing separately from the other two. 
Another question is should I be looking for a lab that test for organic matter? I was planning on using Logan labs saturated paste test. Don't see anything mentioned in that test about organic matter.


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## Ridgerunner (May 16, 2017)

Some factors to consider in deciding to separately test:
Is there an obvious difference in the color of the soil? Is the soil in the areas much darker or lighter?
Is there an obvious difference in the texture of the soil? Is one area like beach sand while the other area is like pottery clay?
Is the turf performing much more poorly in one area than in the rest of the lawn and there are no obvious external factors like differences in irrigation, shade, that children or pets use one area as a play ground, etc?
Is the area large enough to treat separately?
Are you interested in acquiring the materials and willing to make the effort for what could be an extended period of time to treat the area separately?
Is the additional cost of individual testing over a couple of years a factor?
Caveat: if a small area of your lawn is different from the rest of the lawn and you do not wish to test separately or treat it separately, do not include the area in the samples to be sent to the lab.

On using Saturated Paste tests:
Saturated Paste tests are described as "snap shots" of the nutrients in soil solution that are expected to be immediately available for plant uptake. Guidelines for determining fertilizer application for long term nutrient availability have not been established for the test. Other "standard" tests have been developed for that purpose that more predictably estimate the nutrients in soil that are not only immediately available to the plant, but are also expected to become available over a whole growing season. Those test have been "calibrated" and guidelines have been developed from which fertilizer additions can be calculated.
As an analogy, consider a welfare check by Family Services. A Saturated Paste test is akin to the welfare investigator dropping in on a home and observing that a balanced lunch is on the table. It's a poor method of predicting if the caretaker will provide healthy meals on a regular basis unless the investigator stops in for every meal and what is the remedy if there is no meal prepared upon inspection? Although, not a guarantee, a more efficient and reliable indicator that regular healthy meals are being served would be to inspect and monitor the pantry and refrigerator weekly. That would be akin to using the "standard" test.

OM measurement can be useful for a number of purposes. A majority of "standard" tests automatically include it in their reports.


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## Ryan1+2 (Oct 16, 2018)

So based on that I think I will just test them separately. I'm going to use University of Delaware which is only 20 minutes away. Basic test are $15.00. They participate in the NAPT program. 
This is the description of their test. 
B2 - Home Lawn and Garden Soil Test with Lead
Now Includes Lead!!! Soil pH, lime requirement, organic matter, Mehlich 3 extractable nutrients (P, K, Ca, Mg, Mn, Zn, Cu, Fe, B, S, and Al), Phosphorus Saturation Ratio, Estimated Total Lead and recommendations.


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## Ryan1+2 (Oct 16, 2018)

Fell behind on getting my soil samples sent out. Does it matter that the samples were taken almost a month ago and have been sitting in a plastic container on my garage? Will these still produce accurate results or should I pull fresh samples?


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## g-man (Jun 15, 2017)

Last year I did the same and send them. My P results were very low. Lower than the previous year. This year P was back in shape, so I am assuming that the long delay affected the P extraction. The science doesn't make sense in my brain, but it is the only logical reason.


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## Ryan1+2 (Oct 16, 2018)

Well I guess I will just pull more to be on the safe side.


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## Ryan1+2 (Oct 16, 2018)

Although I just realized that I just put down my first spoon feeding app of N which was 32-0-4 and the dimension a few weeks ago which is 0-0-7. I'm assuming this will effect new samples.


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## g-man (Jun 15, 2017)

It might affect the K, but the 0-0-7 is only 7% K, so not a lot.


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## TN Hawkeye (May 7, 2018)

g-man said:


> It might affect the K, but the 0-0-7 is only 7% K, so not a lot.


Is there a recommended "wait" period after a fert application to pull samples? I applied bag rate of a 30-0-4 about 2 weeks ago. I didn't even think about needing to pull samples. My lawn is mostly greened up and I have mowed twice. Thanks @g-man for any suggestions.


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## g-man (Jun 15, 2017)

I think 2 months is ideal, but this is just an opinion. Depending on the lb you used for the 30-0-4, the 4% in K might not matter or influence the results too much.


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## TN Hawkeye (May 7, 2018)

g-man said:


> I think 2 months is ideal, but this is just an opinion. Depending on the lb you used for the 30-0-4, the 4% in K might not matter or influence the results too much.


Thank you for the reply G-Man.


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