Reading Reports
Our soil analysis reports include basic measures, plant nutrients, cations and recommendations based 100% on what is happening in your soil and what your crop or pasture actually needs. Reports are based upon the requirements of the Mikhail System. To make the most of this information, it is important to understand what it is all for.
There are two main soil test packages – ST-1 The Standard Soil Balance analysis & CT-1 The Complete Soil Balance analysis.
Standard soil balance analysis (Code: ST-1)
A 5-page report that includes 25 laboratory tests and 10 calculated results with desirable levels individually determined to suit the specified Land use and characteristics of the soil sample. Two sets of recommendations are provided: one for cation balance corrections to optimise soil structure and other physical attributes. These are based on desirable percentages of the five major cations (Ca, Mg, Na, K & H) as calculated from the Adjusted Cation Exchange Capacity. The recommendations are then given in terms of the most appropriate material (Gypsum, Lime, Dolomite, Magnesite, Magnesium Oxide or Magnesium Sulphate) to provide the amounts of Calcium and/or Magnesium needed. The other set of recommendations is for the plant nutrient requirements relative to the needs of the Land use and what is presently available in the soil.
Important Notes: In determining these requirements and recommendations we do NOT consider the preferences of fertiliser manufacturers, spreading contractors or other ‘external’ factors – ONLY what is going on in the soil and what the Land use requires. Nutrient recommendations cover both major nutrients (N, P, K & S) and Trace elements (Cu, Zn, Fe, Mn, Co, Mo, B) and are provided in terms of kg of the elemental nutrient required per hectare. This means you can take our recommendations to ANY SUPPLIER for conversion into fertiliser applications and make ‘apples-for-apples’ comparisons of their costs and service.
Complete soil balance analysis (Code: CT-1)
A 10 – page report that includes 33 laboratory tests (including Total N & Total P as standard inclusions) and 23 calculated results with desirable levels individually determined to suit the specified Land use and characteristics of the sample. The results are organised in terms of the three Balance components – Structure, Nutrients and Biology to make the report more readable and the information more accessible. Three sets of recommendations are provided: one for Cation Balance corrections to optimise soil structure and other physical attributes. These are based on desirable percentages of the five major cations (Ca, Mg, Na, K & H) as calculated from the Adjusted Cation Exchange Capacity. The recommendations are then given in terms of the most appropriate material (Gypsum, Lime, Dolomite, Magnesite, Magnesium Oxide or Magnesium Sulphate) to provide the amounts of Calcium and/or Magnesium needed. The other set of recommendations is for the plant nutrient requirements relative to the needs of the Land use and what is presently available in the soil. And the third set is for Balanced Soil Biology, using various bioactive materials (eg. Humate, Kelp extract, Fish emulsion, etc) to help manage the relative proportions of five key Indicator Groups of soil microbes – Lactic acid bacteria, Photosynthetic bacteria, Fungi, Yeast and Actinomycetes.
Important Notes: The recommendations are intended to encourage the microbial activity, in order to help accelerate cation balance changes and optimise nutrient availability. See Indicator Groups & Bioactive Materials below.
Understanding your report
Basic Measures
pH, EC, TSS (Colour and texture is an optional extra $22).
The first part of the analysis begins with a section of results which is largely descriptive and includes: a soil colour and texture description (extra cost), measure of pH (soil acidity/alkalinity), Electrical Conductivity and a measure of the soil Total Soluble Salts. These results give an early indication of the soil type and its basic “health” in respect to the level of salts in the soil: in this context salts are referring to all the cations and anions not just sodium. The Electrical Conductivity of the soil gives a measure of the soils capacity to pass an electrical current and is particularly important in relation to the land-use. The higher the Electrical Conductivity is, the higher the potential osmotic pressure in the soil. Osmotic pressure is caused when the concentration of ions in the soil is higher than that in the plants roots. This has serious implications in relation to plant health, as in order to equilibrate the concentration of ions in the roots to that of the soil, nutrients will want to move from the root to the soil when the EC in the soil is higher. The Electrical Conductivity measure of the soil is an important indicator of how well the suggested crop may grow. It is also a good indicator that the cations in the soil are not in balance when the EC is high.
In the report an ideal range for the soil pH, and a maximum desirable level for the soil EC and TSS is given (related to the particular soil sample and land use).
Plant Nutrients
Available Calcium, Magnesium and Sodium
The next set of results are the available Calcium, Magnesium and Sodium found in the soil. These results are expressed in parts per million (ppm). “Available” refers to the amount of calcium in the soil that is available to the plant for uptake. Similarly for Magnesium and Sodium.
Available Nitrogen, Phosphorus, Potassium and Sulphur
These are the major (macro) nutrients needed by crops (generally needed in the tens or hundreds of kilograms per hectare). These figures indicate the available nutrients in the soil, and a desirable level is given based on the land use with respect to the soil cation balance.
The result for nitrogen is “nitrate”. This is usually low due to its high capacity for leaching from the soil profile.
Available Copper, Zinc, Iron, Manganese, Cobalt, Molybdenum and Boron
These are the minor (micro or trace) elements needed by the crop. They often measure in only a few parts per million; nevertheless they are necessary and requirements for these trace elements vary quite considerably.
NPKS & Trace Elements are used to determine fertiliser recommendations, and so must be considered in relation to the intended land use. For example fertiliser requirements will be very different for Citrus, than for Cotton.
Organic Matter and Organic Carbon
Organic Matter is the material in the soil not of mineral origin. It is a very important component of the soil, required not only to contribute nutrients, but as a substrate for microbial activity. Organic Carbon is calculated from the Organic Matter percentage.
Exchangeable Cations
The exchangeable cations in the soil, refers specifically to the Calcium, Magnesium, Sodium, Potassium and Hydrogen attached to the soil colloids. Generally cations vary in their strength of attachment to the charged sites on the soil colloids. According to the Mikhail System based on many decades of research, it has been found, when the ideal ratio of these cations in the soil for crop production is applied, appropriate soil amendments (i.e. Gypsum, Lime, Dolomite or Magnesium Sulphate/Oxide) can be determined.
In a well-balanced soil the cation proportions are:
Exchangeable Hydrogen & CEC
Some laboratories give an estimate of Hydrogen from the pH rather than an actual figure. The Mikhail system is much more advanced. Ted Mikhail’s research found that Hydrogen levels in Australian soils were high to very high, especially in soils with a high organic matter.
Therefore, exchangeable Hydrogen is one of the major elements to calculate the CEC. Without exchangeable Hydrogen, soil CEC is a misleading figure. Consequently, the percentage of exchangeable Calcium, Magnesium, Sodium and Potassium will be higher than what it should be, potentially leading to incorrect recommendations for Dolomite, Lime and Gypsum.
Furthermore, the more organic matter in soil, the higher exchangeable hydrogen will be. Further research in regards to Total Organic Matter and exchangeable Hydrogen confirmed the above.
The conclusion was that a 0.5 me of hydrogen is allowed to remain in the soil for every 1% of organic matter. This has lead to Adjusted hydrogen, which is exchangeable hydrogen minus total organic matter x 0.5. Accordingly, CEC becomes Adjusted CEC which is the sum of exchangeable Calcium + Magnesium + Sodium + Potassium + Adjusted Hydrogen.
The above percentage of exchangeable Calcium, Magnesium, Sodium, and Potassium will be calculated from Adjusted CEC. When these percentages have been determined it is then time to begin looking at and applying the necessary macro and micronutrients required to build the soil to a fully fertile medium.
Ideally in a well balance soil the cation proportions are:
Ca 65-70%, Mg 12-15%, Na 0.5-5%, K 3-5% and H <20% (there is not a precise set of proportions, there is a range of %’s within the soil which will have the physical properties we are seeking).
Recommended Cation Balancing Inputs
If there is any excess of exchangeable Sodium and/or Magnesium, the amount of Gypsum that will supply enough Calcium to displace this excess is calculated. If this is less than the required amount of Calcium, the remainder is provided as Lime.
Where there is an excess of exchangeable Hydrogen, any requirement for Magnesium is filled using Dolomite (based on a Dolomite with 11% Mg and 25% Ca) and the Calcium provided by this material is subtracted from the requirement before the Lime recommendation is calculated.
The Lime recommendation is calculated from the Calcium requirement after the previous two calculations are completed and based on a pure Lime with 40% Calcium. This is the Calcium content of pure Calcium Carbonate and so represents the highest possible quality Lime.
For further information on recommendations please see our Recommendations page.
Microbes
Active indicator organisms (below) with bioactive materials recommendations.
Indicators of Soil Biological Activity
The Biological community in the soil is extremely diverse. To get a proper understanding of its ‘health’ we look at a few so-called ‘indicator’ groups. These have important functions upon which plants and other organisms depend.
SWEP results are for Active Micro-organisms only. This means only those that will immediately grow under ideal conditions (generally about 7-10 % of total biomass). The Active Indicator Organisms are: Photosynthetic Bacteria, Lactic Acid Bacteria, Actinomycetes, Yeasts, Generalised Fungi and Cellulose Utilisers.
1. Photosynthetic Bacteria (like Rhodopseudomonas spp & Bradyrhizobium spp)
– Are important in recycling organic matter, particularly compounds that are difficult to break down – such as pesticide and petrochemical residues. They are also important for synthesis of bioactive compounds that are known to stimulate plant growth. They increase the Nitrogen uptake and Neutralises pesticide residues.
Worm Leachate activates this group.
2. Yeast (such as Saccaromyces spp, Dabaryomyces spp, Torulopis spp & Rhodotrula spp)
– Synthesise plant growth substances from amino acids and sugars that are produced by photosynthetic bacteria. These substances include hormones and enzymes that promote active cell division and root growth.
Fish Emulsions activate this group.
3. Lactic Acid Bacteria (such as Lactobaccillus spp, Leuconostoc spp & Pediococcus spp)
– Produces lactic acid from sugars and carbohydrates. Lactic acid is a strong bio-suppressive compound that helps control harmful micro-organisms. This effect, together with other trace nutrients produced by members of this group, is particularly beneficial to the growth of photosynthetic bacteria and yeasts.
Molasses & Fish Emulsions activate this group.
4. Actinomycetes (such as Actinomyces spp & Streptomyces spp)
– Produce anti biotic compounds that are effective suppressants of pathogenic organisms (anti disease for the plant). They have also been shown to produce plant hormones – especially when treated with Kelp extracts.
Kelp & Worm Leachate activates this group.
5. Active Fungi (Generalised Fungi and Cellulose Utilisers)
(a) Generalised Fungi (such as Aspergillus spp. Penicillium spp, Mucor spp & Rhizopus spp) have many benefits on plant growth – these include the production of enzymes, antibiotics and various growth regulators. They are also important in the conversion of organic matter to humic substances.
(b) Cellulose Utilisers (like Trichoderma spp) require only minerals and cellulose for growth. These fungi breakdown plant remains into organic materials that are beneficial to other microorganisms such as Protozoa. Cellulose utilisers break down cellulose (decomposes the straws of a plant – organic matter in the soil), thus increasing the formation of humus and helping to improve soil structure.
Kelp, Mulching or Green Manuring activates this group.
Bioactive Materials
Kelp Extracts contain high concentrations of plant hormones. These have been shown to significantly increase the biological activity in soils, especially that of Actinomycetes & Cellulose Utilisers.
Molasses provides a readily metabolically carbon and energy source for soil organisms. It is of particular value to Yeasts & Lactic Acid bacteria, however being quickly utilised it will provide only a short-term benefit unless other actions have been taken to improve the soil environment.
Worm Leachate contains a range of growth promotants that are of particular benefit to Photosynthetic Bacteria & Actinomycetes.
Fish Emulsions are a source of readily available organic Nitrogen and can be especially useful when this is needed to improve the carbon- nitrogen ratio in the soil. They’re also beneficial in stimulating growth and activity of many microorganisms especially Yeasts and Bacteria. The net effect is an increase in the potential for nitrogen cycling, and so somewhat reduces the requirement for nitrogen inputs to some crops and pasture, however for this potential to be realised other corrective measures must be applied first. Be aware that some fish emulsion products have added nutrients to render them appropriate for use as conventional fertilisers and that the concentrations of products vary significantly.
Liquefied humate adds carbon to the soil in the form of humic substances. Adjusts the carbon-nitrogen ratio in the soil. It releases bound nutrients into plant available forms and helping to improve soil structure. The direct effects on soil biology are similar to those of kelp extracts.
Mulching or Green Manuring is an effective means of improving organic matter levels and protecting soil structure in cultivated soils. For Pasture, regular light harrowing (after grazing) and adjustments to normal grazing practices will have the same effect.
The breakdown of this mulching is initially conducted by soil Fungi (especially in clay soils).