Central NE | puff33m - 11/13/2012 10:24 . Why bring sand to the beach, is 150 lbs of DAP as a maintenance application even relevant, or can a functional microbiological system release "insoluble, yet available" P? (I'm not trying to sell you this idea, just share a perspective). In the soils here, my soil test is 50 ppm P or 100 lbs per acre furrow slice. I have tested down to 3 feet, and it is also about 50 ppm to those depths, so using a 3 foot deep root system of crops and covers, do I potentially have 6x the "insoluble, yet available" P as that described by Brady & Weil?
I would call that P soluble, but less available and I don't think it is the P as described by B&W. Assuming you ran the same test on all samples, and the testing process is identifiying only available P.
My opinion: The "insoluble, yet available" P that is reffered to can be much, much higher than 6X (not on your sand) and is only "yet available" with the type of biological activity you described in your notes posted above. In my soil, P levels that test between 17 and 45 on a soil test or even lower at depth, but test 1500ppm when testing it as a manure sample (which assumes 100% organically available)...at both a 8" depth as well as 10'ft. That is a heckofalota P, and indeed why does an eskimo need an ice maker?
Thanks for posting. You still didn't reveal the speaker. Is it a secret?
Edited by Hayinhere 11/13/2012 15:00
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Some thoughts on fungi and nutrients
