EXPLANATION OF SOIL ANALYSIS

1. pH – The pH expresses the acidity or alkalinity of the soil. A satisfactory range for most crops is 6.0 to 7.5. A pH above 8.0 indicates a probable sodium problem.
   
2. ECe – The soil salinity is expressed as the electrical conductivity of a water saturation extract (ECe). The ECe is useful to evaluate changes in soil salinity and the suitability of a soil for crop growth as follows:

ECe	Crop Responses
<2	Little or no salinity problems
2-4	Restricts growth of more sensitive crops
4-8	Restricts growth of many crops
8-16	Only tolerant crops yield satisfactorily
>16	Few tolerant crops yield satisfactorily

3. B – Boron is essential in small amounts for crop growth, but it is toxic at higher levels. General guidelines for crop growth are as follows:

PPM	Crop Responses
< 1.0	Satisfactory for most crop growth
1.0-4.0	Satisfactory for moderate to tolerant crops
> 4.0	Acceptable only for most tolerant crops

4. Ca and Mg – Calcium and magnesium levels are primarily affected by soil type, drainage, and cultural practices. Concentrations of both ions increase with increasing soil pH. Calcium deficiencies are rare when soil pH is adequate. Magnesium deficiencies commonly occur in sandy, low organic soils.
   
5. Na – Sodium is usually considered in relation to Ca and Mg (see SAR) for its affect on soil condition. Relatively high levels of Na generally cause problems with soil water infiltration and plant growth.
   
6. SAR – The sodium adsorption ratio is a measure of the amount of sodium on the soil exchange complex relative to calcium and magnesium. It may be used to evaluate soil conditions as follows:

SAR	Expected Result
< 9	Generally no water infiltration problems
9-13	Increasing water infiltration problems
> 13	Water infiltration problems in all soils

7. Gyp – The amount of gypsum (tons per acre) required to help correct a soil water infiltration problem due to excess sodium. This value is estimated and reported when the soil SAR value exceeds 9.0.
   
8. NO3-N – Soil nitrated expressed as nitrate nitrogen (NO3-N). Multiply this value by 4 to get pounds per acre of available nitrogen. Consult an agronomist for interpretation of this value pertaining to crop N requirements.
   
9. PO4-P – Available soil phosphorus. Consult an agronomist for interpretation of this value pertaining to crop P requirements.
   
10. K – Available soil potassium. Generally values in excess of 120 to 150 ppm are adequate for most crops. Consult an agronomist for interpretation of this value pertaining to crop K requirements.
    
11. Zn – Available soil zinc. Generally values in excess of 0.5 to 4 ppm are adequate for most crops. Consult an agronomist for interpretation of this value pertaining to crop Zn requirements.
    
12. Cu – Copper levels between 1.2 and 1.8 ppm are usually sufficient for crop growth. Factors contributing to copper deficiency include: soil pH above 7.0, high organic matter, and soils receiving high rates of nitrogen, phosphorus, or zinc. Soil applications are usually effective for several years. Foliar applications are also effective.
    
13. Mn – Optimum test levels of manganese typically range between 14 and 22 ppm. Manganese quickly becomes insoluble when added to soil. Applications should be banded or consist of foliar treatments.