Abstract
A review of samples from 42 dairies in Idaho showed that nitrogen (N) and phosphorous (P) in wastewater lagoons vary greatly between farms and from year to year. So manure should be tested as close to the date of application as practical. This four-page publication details how to sample and prepare manure for lab analysis. It also suggests how to find someone to analyze manure samples, what a manure analysis report will tell you and what information is most useful. Illustrations show a liquid manure sampling device and also a composite sampler for slurries, lagoon sludge or settled solids.