I really need to sit down over the winter and look at the research behind the banding of "deficient", "excessive" etc. because at the moment raw data isn't going to mean anything to me. I do wonder why it is that the lower results are given in mg/kg whereas the top results are given as %s. Obviously mg/kg figures have the problem of the differing atomic weights of the different elements. That said, to me that tissue result is extremely plausible and fits the jigsaw very well and it's not as if the lab knows the story behind the sample and so can fiddle the results in some way.
I can see how different lab's extraction methods will give different readings and I can also see how it is debatable where to set the line between good, bad and so on but I don't see why %s are any less raw (if the figure gives the % of ions of that element in solution as is my guess) than ppm or mg. Can you explain.
Yes the raw data is essential in that the labs give their opinion not based upon researched data. And science fact. In so much as that be it a lab which has potential commercial gain or an apparent " Independence" The fundamental underlying facts seem to have buried in a rush to adopt the present norms. Which IMO is wrong in so much as we as growers need to work with nature not fight her. Hence my well known view that hand held N leave sensors work as a predictive tool.
It is a bit like the long standing debate here and elsewhere regarding Albrecht based soil sampling and " Standard norms" both analysis are valid but different in their results. It depends upon extraction methods used. The conclusions of both could and will be contested in regard to more calcium or sulphur etc. My personal choice is to revert to raw data from a tissue analysis.Which cleaarly indicates what the crop we trying to grow is actually getting from the enviroment in which it grows.
As in my earlier post the two graphs show nutrient uptake/need. From independent researchers combined peer reviewed studies.
Please do hope you continue to look at things. Regards