Reference for Soil Analysis

 Based on 6” depth samples.  Percentages and values will vary based on Sample depth, pH, compaction, and stress factors.
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REFERENCE                       DEFINITION/RESULTS

pH                                           pH measures the acidity and/or alkalinity of the soil. It's important to understand that pH should not be the focus of any management program, it only represents the "percentage of hydrogen" that is found in the soil colloid. The pH balance of basic cations are found in the base saturation and is easily managed by managing Ca, Mg, K, Na and other cations

Organic Matter Percentage  Organic matter encompasses the roots and thatch, both of which are forms of (OM%)                                   carbon that and are not easily digested by soil microbes. Organic matter is very                                                 important as a foundation for the development of humus; however it does not                                                 represent pure humus in soil.

Total Exchange Capacity     The holding capacity of the soil. The TEC represents the soils ability to

(TEC)                                     maintain nutrients on colloidal sites.  Colloidal sites are plate-like structures that are made up of mainly clay and organic matter. There are other elements that can increase TEC, such as sands, where clay and organic matter are low. However, in heavy soils, the TEC will be greater.

ANIONS

Sulfur (S)                               Sulfur should be maintained at levels between 50 and 100 pounds per acre seeing how it plays a major role in mobilizing excessive nutrient levels out of the soil. Sulfur is important for the uptake of nitrogen and development of amino acids, enzymes and protein systems. (Sulfur levels are calculation in parts per million (ppm), when multiplied by 2 equals pounds per acre)

Phosphorus (P₂O₅)                Phosphorus levels should be maintained around 250 pounds per acre except in heavy soils where levels can be higher. Phosphorus is an essential building block for the development of sugar, healthy roots and for transporting other nutrients into the plants.

MAJOR ELEMENTS

Calcium (Ca)                         Calcium percentage should be maintained at a base saturation of 68% in heavy soils and at 60% in sandy soils. (Calcium is noted in pounds per acre and the base saturation percentage shows the balance of calcium with other cations.) Calcium when not balanced will severely affect soil compaction by restricting air and water flow through the soil, limiting microbial activity. Depending on how much Ca is needed; a combination of high calcium lime (low Mg) and dolomitic lime (high Mg) may be needed to avoid driving off too much Mg.

Magnesium (Mg)                   Magnesium percentages should be maintained at a base saturation of 12% in heavy soils and close to 20% in sandy soils. Mg is shown in pounds per acre and has a close relationship with Ca.  Often times high Mg drives up the pH balance. Magnesium is essential for photosynthesis and the development of amino acids and enzymes systems.

Potassium (K)                        Potassium is important for reducing plant stress and root development. Potassium percentage should be maintained at a base saturation of 5%. When the pH level is above 6.5, potassium availability is limited and without the use of organic sources becomes very difficult to build up levels of K.

Sodium (Na)                           Sodium percentages should be maintained at a base saturation of 3% or 40-50 pounds per acre. Soils with high levels of Na will restrict activity of beneficial bacteria and could result in a sodium-induced wilt

Base Saturation                     The base saturation percentage always adds up to 100% representing a

Percentage (BSP)                  balance in the soil, 68% Ca, 12% Mg, 5% K, 2% Na, 3% other base trace                                                 nutrients and 10% H) This is where soil management begins and if the                                                 percentages stay within their "ideal" values, pH will always be between 6.0 - 6.5.

MINOR ELEMENTS

Boron (B)                                           Boron is a very soluble nutrient and is the "gate keeper" for calcium uptake. Boron should be maintained at 1.2 ppm and is needed in most soils on a small basis. Boron can be very toxic but is needed to with the uptake of nitrogen as well as many other plant/soil functions.

Iron (Fe)                                             An ideal iron level in soil is 100-150 ppm (higher levels are tolerable for most soils). There is a crucial Fe:Mn relationship in soil which should always be at least 1.5:1

Manganese (Mn)                               Manganese levels should be maintained at 25-40 ppm minimum to 120 ppm maximum. Mn mobilizes Fe in the soil and can be used as a good Fe replacement. Mn plays an important role is the metabolism of plant and soil microorganisms. When there is a lack of Mn this can create plant stress, encouraging diseases.

Copper (Cu)                                      Copper levels should be maintained at 5 ppm minimum to 10-15 ppm max. Copper is a major player is disease suppression and is a major ingredient in many fungicides.

Zinc (Zn)                                            Zinc level should be maintained at a minimum of 6 ppm to a max of 10-20 ppm. Zinc plays a major role in disease suppression in soil.