Sample Information
This section contains sample information provided by the client, including sample identifier, description of intended use, waste code, grower comments, and land application method. The waste code provided by the client determines which tests will be applied to each sample. The application method determines the units that are reported (lb/ton or lb/1000 gal) in the Estimate of Available nutrients and also determines the nitrogen availability estimate for non-composted animal manure samples. Application methods for liquid samples are irrigation (IR) and soil injected (IN) and for solid samples are broadcast (BR) and soil incorporated (SI).
Nitrogen
This section reports the total concentration of nitrogen (N or TKN) in ppm (mg/kg or mg/L, respectively). Nitrogen is reported on an as-received (wet-weight) basis for all liquids and for all manure-based solids. Solid Industrial by-products (e.g. paper fibers, ash, non-composted crop residues, etc.) are reported on a dry-weight basis.
Inorganic nitrate-nitrogen (NO3-N) and ammonia-nitrogen (NH4-N) are not part of the standard analysis and are only analyzed by request at sample submission. Results are reported in parts per million (ppm) which is equivalent to mg/kg for solids or mg/L for liquids.
Other Plant Nutrients
Concentrations of phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), and boron (B) are reported in parts per million (ppm), which is equivalent to mg/kg for solids and mg/L for liquids. All solids are reported on a dry-weight basis. All liquids are reported on an as-received (wet-weight) basis.
Estimate of Nutrients Available for First Year
The nitrogen availability estimate depends on the manure type and application method that you specify on the submission form and accounts for the fact that only 40-60% of the manure nitrogen becomes available within one year of application. The nitrogen availability calculation for specific manure types was established by the North Carolina Interagency Nutrient Management Committee.
All other elements and nitrogen from non-manure waste sources are reported as 100% available in the first year of application. Concentrations are reported on an as-received (wet weight) basis for all elements in lb/ton for solids or lb/1000 gal for liquids.
Carbon
Carbon (C) is measured on solid organic materials primarily to determine the carbon to nitrogen ratio (C:N). Carbon to nitrogen ratio is an important parameter in composting, both for feedstocks and finished product.
Sodium, Chloride, and Aluminum
Sodium (Na) and chloride (Cl) are elements that may be important for plant nutrition but are more often detrimental to plant health in excessive levels. Aluminum (Al) is not a plant nutrient and may create toxicity when soil or substrate pH is excessively low.
Other Parameters
EC (Electrical Conductivity) is reported in units of mS/cm. It measures the total quantity of dissolved salts (ions) in solution. It may be used as a general evaluation of the total nutrient concentrations available to plants. However, it also includes elements such as sodium (Na) and chloride (Cl), which increase EC without providing nutritional value. In addition, excessively high EC will burn plant roots regardless of the whether the ions are required for plant nutrition.
SS (Soluble Salts) is the same as EC, but is expressed in units of 10-5 S/cm.
pH is the level of acidity or basicity as measured by the amount of hydrogen ions (H+ ) in solution. It ranges from 0 (acidic) to 14 (basic) on a logarithmic scale; 7 indicates neutrality. It can reduce the availability of micronutrients (Fe, Mn, Zn, Cu, B) when pH is high (>6.5) and the availability of macronutrients (N, P, K, Ca, Mg, S) when pH is low (<5.0).
Bulk density (BD) is a measure of how heavy the organic material is, relative to its volume, and it reported in lb/yd3. It is an optional test that is sometimes used to measure compost quality.
CCE% (Calcium Carbonate Equivalent) represents the acid-neutralizing capacity of a material expressed as weight percentage of calcium carbonate. For waste materials with liming potential (e.g., lime-stabilized biosolids, ash, poultry layer litter), the application rate may be limited by a high CCE%. Waste with a high CCE% should only be applied at rates needed to increase soil pH to the desired target. Overapplication can lead to high soil pH, which may limit micronutrient availability.
ALE (Agricultural Lime Equivalent) indicates the amount of the sample material that provides a liming effect equivalent to one ton of agricultural grade limestone. For example, an ALE of 2 indicates that 2 tons of the sample material would have the same liming effect as one ton of limestone.
DM% (Dry Matter) is the percent of the as-received sample that is dry solids and is inversely related to percent moisture. It is used in semi-solid and solid samples to convert the dry-weight nutrient measurement concentrations (mg/kg) back to wet-weight concentrations of the original sample, which are reported in the estimate of nutrients available for first year (lb/ton).
Conversion Factors
lb/ton × 4.17 = lb/1000 gal.
lb/1000 gal. × 0.24 = lb/ton
Fertilizer grade (%) = mg/kg or mg/L ÷ 10,000
This page was last modified on 05/28/2024