Soil Analysis provides an objective measurement of available nutrients in the soil as well as pH, Electrical Conductivity, Phosphorus Buffering Index (PBI)
- Independent Laboratory
- Rapid Turnaround
- Uses PBI - the new national P sorption standard.
- Indication of some Trace Elements
- Practical recommendations by Area Managers
|Nutrient||Symbol||Units Used||Adequate Range Expected||Comments|
|Phosphorus||P||ppm (mg/kg)||15 - 45||Dependent on crop/pasture type and soil type.|
|Potassium||K||ppm (mg/kg)||40-120||Lupins and Canola are less sensitive to K deficiency. Clover and Medic require higher soil levels|
|Sulphur||S||ppm (mg/kg)||5 - 15||Dependent on soil type|
|Nitrate||NO3||ppm (mg/kg)||up to 30||Very mobile in the soil. May be lost to leaching.|
|Ammonium||NH4||ppm (mg/kg)||up to 20||Stable in the soil as it is a cation, but converts to Nitrate readily.|
|Copper||Cu||ppm (mg/kg)||>0.3||Soil tests for Copper are a guide only.|
|Zinc||Zn||ppm (mg/kg)||0.12-0.5||Dependent on soil pH. The more alkaline the soil (higher pH) the higher the soil Zinc level needs to be.|
|Organic Carbon||O.C.||%||1.0 - 3.0||Dependent on soil type and rainfall.|
|Electrical Conductivity||EC(salt)||dS/m||<0.02||Levels <0.2 are generally considered negligible. Levels >0.8 can be said to be accumulating salt, and should be investigated further.|
|pH||(CaCl2)||>5.0||Economic responses to applying lime to increase pH above 5.0 are doubtful. If subsoil pH is low, it may be necessary to increase topsoil pH >5.5 (CaCl2)|
|Aluminium||(CaCl2)||5.0||As pH declines (becomes more acidic) Aluminium levels can increase in some soil types. High Aluminium levels will affect root growth reducing their ability to explore large volumes of soil and therefore their access to nutrients and soil moisture. (Read the article on soil pH here)|
PBI is a function of soil type. Generally as a soil contains more iron, clay and organic matter, the higher the PBI.
Other nutrients can be analyzed on request. Most commonly now farmers are asking for Cation Exchange Capacity (CEC) which involves analyzing for calcium, magnesium and sodium in conjunction with the potassium test to calculate CEC.