About The Livestock Waste Testing Lab (LWTL)
Manure Analysis
We test livestock and other wastes, interpret and make science-based recommendations for properly managing the resource while maintaining soil quality for sustainable Florida agriculture and environment. The LWTL offers analytical tests, interpretations and nutrient recommendations for animal manure and other waste by‐products. The laboratory services and the educational programs are available to all citizens of Florida and are provided as a fee-based service. These services are offered through the Soil, Water, and Ecosystem Sciences Dept. as part of the UF/IFAS Nutrient Management Program led by Dr. Thomas Obreza.
How To Get Started!
Samples can be delivered to the LWTL via packaged mail or dropped off in person on any working day. All samples should be appropriately labeled along with completely filled out forms and any applicable fee. Appropriate forms can be downloaded and printed from the link above. All the requested information on the forms must be provided including the crop codes, county of sample origin, current method of application and previous application history, if any. For poultry litter samples, at least one half‐quart plastic bag volume of sample should be provided. For all liquid, effluent, and slurry samples, only leak‐proof bags or bottles should be used. Samples must be appropriately labeled with grower’s name and sample ID. Samples should be delivered to the address provided on the form.
Manure Analysis Submission Forms
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What Constitutes A Manure Test?
Laboratory analysis will include a test for nitrogen (N), ammonium (NH4‐N), phosphorus (P) and potassium (K) as well as moisture (%), solids (%), ash (%), and pH. Based on test results, nutrient recommendations for N, P, and K are provided for selected crops. Up to three crop types per sample can be selected from a given list.
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How Do I Interpret My Manure Test Report?
Each report includes a nitrogen (N) and a phosphorus (P) based recommendation for land application. These recommendations are determined by the crop chosen and the nutrient values in the sample. Nutrient values in the raw sample are provided on page 2 of the report. Economic value of the manure is based on quarterly fertilizer prices using ammonium nitrate, concentrated superphosphate (0-46-0) and potassium chloride (0-0-60) at current market prices.
The bar graph given on page 1 of each report includes compensation for N loss during application for liquid and solid samples. Percent loss depends on the type of manure and the application method. Solids generally have a 5% expected loss. If manure is not incorporated into the soil within 24 hours, assume a 25% loss of N due to volatilization. Liquid applications have an automatic 25% N volatilization loss before they are stabilized in the soil. For liquid samples, up to a 25% N loss is accounted for if pH is greater than 7.0 and an additional 25% N loss is also assumed when the liquid manure is applied through sprinklers.
Application rates are given for individual crops based on UF/IFAS recommendations assuming "low" P and potassium (K) soil tests. Splitting applications three times is encouraged following UF/IFAS Best Management Practices. A standard soil fertility test should be run two times per year for maximum effectiveness.