soils 3

Title: soils 3
Mike:  Below are my estimates.  The value should be that number of higher if
I gave one number.  Research shows that the balance of cations are not
important for crop growth.  Most of the plant nutrients are actively
absorbed meaning the level of one does not influence the uptake or another.

%OM= 2.5%     N= 5 ppm at end of season weakbray P= 35 ppm Stored P= N/A
K=300 ppm Mg= 50 ppm           Ca=          Na= less than 5% of saturation
>
> So4-s= 10 ppm Zn= 1.0 ppm Mn= 2.0 ppm fe= 5.0 ppm  Cu= .3 ppm B=.5
> %k= N/A          %Mg= less than 50 %
>
> %Ca N/A      CEC= Depends on texture and OM concentration  PH= 5.8-7.3
nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn

I will give you values that I think would be ideal for good plant nutrition.
These are for the top 6 inches unless otherwise stated.

%OM= >3.0         N= 20 ppm/2foot       weakbray P= 30            Stored P=
K=250
Mg= 400          Ca= 1500         Na= 5

So4-s= 6/2foot         Zn= 1.00           Mn=2.0          fe=10          Cu=
5         B=1.0
%k=7           %Mg= 20


%Ca 50      CEC= 25        PH=6.5

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
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You have asked a loaded question.  There are many factors that go into designing a "dream soil"  for example a soil ideal for corn or soybeans is not ideal for blueberries or grapes.  I am going to assume you are looking for a non acid favoring crop like most of our production soils in the Midwest.  You may have volcanic soils in your region of the country vs. our deep loess soils of Illinois.  Therefore, since you are sending me the question I am going to give you an answer for the soils found in the Midwest.  In Illinois where we are located we are looking for the following levels.  The info is in ppm as you requested.
%OM - not a big factor for high yielding crops.  Generally the greater the OM the more Nitrogen that is released for Nitrogen loving crops such as corn, alfalfa, wheat and so on.
N - again this nutrient is important to many crops and depending on what you will be growing and also what was grown in the field previously will determine the rate.  Corn for example in Illinois calls for 1.2 lbs of N per bushel of corn expected (yield goal).
Weak Bray P - a soil test greater than 23ppm
K - a soil test greater than 150ppm
Mg - % base saturation greater than 10%
Ca - % base saturation greater than 65%
Na - Not a problem in the Midwest because of our high rainfall.
Zn - greater than 5 ppm (0.1 N HCl extraction)
Mn - greater than 20 ppm     "
Fe - greater than 15 ppm     "
Cu - greater than 0.9 ppm     "
B - greater than 1 ppm (Hot water soluble)
Sulfur - greater than 10 ppm ( ca(H2PO4)) extraction
K% - % base saturation between 2.5% - 5%
Your Mg, Ca percentages are listed above. We don't use the ppm numbers in Illinois, only the % Base Saturation.
CEC ranges from 0 to just under 30 CEC in Illinois
pH Ideal is 6.0 - 7.0  Our soils tend to be acid in Illinois so we add ground Limestone to bring the pH up to 6.5 ideally.
If you run your soil test and assure that everything measured is equal to or above the guidelines you will be risk free of nutrient deficiency for Midwestern crops.  
For your information we are finding that most of our yield limiting factors in the Midwest are non nutrients but instead the soil profiles physical characteristics.  For example compaction, lacking field drainage tile, over tillage and so on.
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