pH is an indication of the relative acidity or alkalinity of the soil. It is based on a logarithmic scale from 0 to 14, with 7 being neutral. Being a logarithmic scale each change of 1.0 unit is a 10x unit change. For example a soil pH of 6.0 is 10 times more acid that a pH of 7.0. A soil pH of 5.0 is 100 times (10x10) as acid as a pH of 7.0. Most plants perform best and a wider range of nutrients are adequately available with a soil pH between 6.0 and 7.0. However, some plants require more acid soils. Few, if any do better with soil pH higher than 7.0. For more information on soil pH click here.

Buffer pH

This is a test that is conducted to determine the amount of lime to apply in order to reach the desired soil pH. It does not represent the intended or target pH for that crop or plant. This test is required due to the effect of the soil CEC. For more information on buffer pH click here.


All are reported with a status assignment (Low, Medium, Good, High, and Very High). The standard agricultural report has the first letter of each status printed with the result, while the other reports use the bar graphs to indicate the status.

Phosphorous (P)

Reported in pounds per acre or parts per million (ppm x 2 = lb./A), depending on the report. These status ranges may be unique for specific crops or plants.

Potassium (K), Magnesium (Mg), Calcium (Ca)

These are the three major cation elements and are reported in the same format. The amount contained in the sample is reported in either pounds per acre or parts per million (ppm), depending on the report format. These status ranges may be unique for specific crops or plants. Additional information is reported as the percent saturation of each element. Percent saturation is best described as the percent of the CEC that is occupied by the element. The desirability of a particular percent saturation for each of these nutrients is sometimes affected by other soil conditions and the plant species to be grown. For more information on calcium and magnesium click on the individual element.

Sulfur (S), Boron (B), Zinc (Zn), Manganese (Mn), Copper (Cu), and Iron (Fe)

Each element is reported in parts per million (ppm). The reported Cu and Mn recommendations are derived by a proprietary formula that calculates the effects other soil factors on the availability of Cu and Mn. For more information on sulfur, boron, zinc, manganese, copper and iron click on the individual element.

P2 Phosphorous

This is the Bray P2 phosphorus test. It is a test developed many years ago to monitor the effects of large applications of rock phosphate fertilizer, which is very slowly soluble. It is sometimes used as an indicator of the "reserve" phosphorus supplying power of the soil. This is a controversial practice and Spectrum Analytic does not use this value in evaluating soils or making recommendations.

Sodium (Na)

Sodium is reported both as parts per million (Na ppm) and percent saturation (Na Sat %). Sodium is not a nutrient, and it is typically a major component of the soluble salts value (see the following section on soluble salts). High levels of Na are detrimental to both plant growth and soil structure, and many of the guidelines are based on the percent saturation of Na.

Soluble Salts (Salts)

Soluble salts are reported as a measurement of electrical conductance of the soil solution called millimhos/centimeter (mmhos/cm). This value increases as the salt content of the soil increases. High levels of soluble salts are generally damaging to plant growth. However, plant tolerance of soluble salts is highly variable between species.

Nitrate-N (NO3-N)

Nitrate-N is the predominant form of N used by most plants. It is also the form most easily lost through adverse environmental and soil conditions. The level of nitrate reported is NOT used in the nitrogen recommendation due to the many variables that can affect ultimate plant availability.


Soil texture refers to the percent sand, silt, and clay contained in the soil. The proportions of these components determine the name assigned to the soil (sandy loam, silty clay, etc.) as shown in the USDA textural triangle. The name of the texture is reported in one column, with the percentages of sand, silt, and clay in the following 3 columns. This information has several applications, but is probably used most frequently to identify drainage characteristics of the soil