How to Properly Sample Silage
Sampling During Harvesting
Collect three to five handfuls of chopped forage from the middle of a load during unloading, place in a plastic bag, and refrigerate immediately. Follow the same procedure for several loads throughout the day. Combine samples from a single harvested field and mix well. Place the entire sample in a clean plastic bag or other container, and seal tightly. Label each container with your name and address as well as the date, sample number, and forage type. Store the sample in a cool place (do not freeze) until you send it to a laboratory for analysis. Repeat for each field, variety, or hybrid. If filling tower silos or silo tubes, keep a record of where each lot is in the silo or tube. Feeding colored plastic strips through the blower at the end of each lot may help identify the lots later.
Silos with seepage should be resampled upon feeding because loss of soluble compounds due to seepage will increase dry matter, acid detergent fiber and neutral detergent fiber, and decrease crude protein. Similarly, resample silos at feeding that were filled with forage at less than 50% moisture that may have heated excessively, causing increased acid detergent fiber and acid detergent fiber insoluble nitrogen. Recheck dry matter of silages at feed out. Fiber and protein are not likely to change much during storage, except as mentioned above, but moisture can change significantly.
Ensiled material from a tower silo
Do not sample the spoiled material on the top or bottom of the silo; wait until 2 to 3 feet of silage have been removed. Collect a 1 to 2 pound sample from the silo unloader while it is operating. Collect samples from opposite sides of the silo. Combine the samples and mix well. Place the entire sample in a plastic bag and handle as discussed above.
Ensiled mater from a bunker silo
If feeding with a TMR (total mixed ration) mixer – Load silage from bunker into TMR mixer and mix well. Take several grab samples to collect a 1 to 2 pound total sample. Place in a plastic bag and handle as discussed above.
If not feeding with a TMR mixer – Collect a 1 to 2 pound total sample from the different vertical layers of the silo face. Grab several handfuls from freshly exposed forage after the day’s feeding has been removed. Do not sample the spoiled material on top of the silo. Combine handfuls and mix well. Place the entire sample in a clean plastic bag or other container, and seal tightly. Store immediately in a cold place until shipping. Label each container as indicated earlier. Place in a plastic bag and handle as discussed above.