Developing a nutrient management plan depends on testing manure for nutrient content. Your manure test results are only as good as your sample. This page outlines recommended ways to sample solid manure from open feedlots.
Sample During Loading
The recommended sampling for solid manure is to sample while loading the spreader. Sampling the manure pack in a barn directly has been shown to result in very variable results and is not recommended. Take at least 5 samples during the process of loading several spreader loads and save them in a bucket. When all of the samples are collected, thoroughly mix the samples and take a subsample from this to fill the lab manure test container.
Sample Manure During Spreading
Spread a tarp or sheet of plastic in the field and spread manure over this with the manure spreader. Do this in several locations and with several loads of manure. Collect the manure from the tarp or plastic sheet in a bucket. Mix the manure collected from different locations and spreaders, and take a subsample from this to fill the lab manure test container. This procedure is usually only practical for more solid manures.
Sampling Daily Haul Manure
Place a 5 gallon bucket under the barn cleaner 4 or 5 times while loading the spreader. When all of the samples are collected, thoroughly mix the samples and take a subsample from this to fill the lab manure test container. Repeat this several times throughout the year to determine variability over time.
Sampling Manure in a Poultry House
Collect 8-10 samples from throughout the house to the depth of the litter to be removed. Samples near feeders and waterers can be very different. Collect samples from these areas proportional to the space they occupy in the house. When all of the samples are collected, thoroughly mix the samples and take a subsample from this to fill the lab manure test container. A sample taken while loading the spreader or during spreading is likely to be a more representative sample.
Sampling Stockpiled Litter
Take 10 samples from different locations around the pile at least 18 inches below the surface. When all of the samples are collected, thoroughly mix the samples and take a subsample from this to fill the lab manure test container. Large diameter auger bit and portable drill or soil sampler can be used to access manure deep within pile.
Sampling stockpiled manure. Picture Source: Manure Testing for Nutrient Content
Sampling Manure from an Open Lot
These videos were produced by the Iowa Learning Farms project.
Sampling Stockpiled and Composted Manure
Related Web Pages
Overview of Manure Testing
- Step 1. Manure Sampling
- Solid Manure Sampling Procedures (you are here)
- Liquid Manure Sampling Procedures
- Step 2. Manure Test Results
- Step 3. Total and Available Nutrients
- Step 4. Manure Test Record Keeping
Page Authors: Douglas Beegle, Penn State University and John Peters, University of Wisconsin