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Little River, TX | Bill & Bill are mostly in agreement.
As to soil labs, I presently use Midwest Labs for two reasons. They will run the chemistry that is appropriate to my soil types. They are good in responding to my questions and odd opinions. They have a few opinions of their own that I must work with.
Like many Labs they are suspicious of a CEC value much above 15 meq/100g. Considering the soils in their primary customer base this is understandable. When building a computed CEC, their reported Calcium results in roughly a 65% Ca saturation, and a CEC in the low meq/100g range. From the beginning I have used their measured CEC values which are roughly double their computed CEC values.
A high CEC soil has it's advantages, but it also has it's disadvantages. The major disadvantage is our corps will have vi sable potash deficiency, as well as tissue analysis potash deficiency at a soil test level usually considered very high. To find enough K in my corps I must fertilize to what might be considered excessive, K ppm, levels. Seldom is this a problem, except for our TAMU extension types. The local USDA people appear to have no problem with the concept.
I try to let Midwest Labs know I am not in a lather for results from my soil and tissue analysis. I pull these samples at the appropriate time for tissue sampling of the second cutting of alfalfa. I sample a field the last year it is in alfalfa. I apply all the fertilizer I expect the next stand of alfalfa will require, prior to planting. I then have soil and tissue analyses the first and second years back in alfalfa.
For farming ground where the fertilizer is applied in bands I would think tissue analysis is the only reliable method to determine if any element limiting production.
My one bitch with every Lab I have used is their failure to recognize an out of ordinary value. With just one or two samples to work with I would not expect them to recognize a 150 ppm K value is not usual in a soil that normally test 450 ppm K. What grabs me is when they do not recognize this situation when they have 18 samples in front of them and still fail to notice one or two odd results, they soon learn to expect a message. | |
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Soil Testing Labs
