By Warren Rusche
Proper sampling of forage is essential if we want to obtain an accurate indication of the nutrient composition, dry matter content, or value of any feedstuff. Correct sampling and analysis is even more important under conditions that might increase feedstuff variability, such as challenging growing conditions. Sampling procedures vary depending upon the type of forage and whether or not sampling occurs pre-harvest or after the forage has been stored.
Forage in a Windrow Prior to Baling
With a sharp shears, cut 6-inch sections from several locations in the windrow. If the forage is dry, take extreme care to avoid losing leaves. Cut the sections into pieces about 1 inch long and mix samples in a clean container.
Forage Prior to Silage Harvest
If forage in the windrow or standing corn or sorghum is to be harvested with a forage chopper, several rounds can be chopped from a representative part of the field. Collect small samples from various locations in the forage wagon, and mix thoroughly in a clean container. As an alternative method, a representative sample of standing forage can also be cut off, run through a chipper, and then a sub-sample of the chopped material used for moisture testing.
Use a hay probe to collect samples. For large round bales the probe should be inserted from the rounded side into the center of the bale. Square bales should be probed from the middle of the butt end.
Silage
For bagged silage, collect about 2 gallons of silage by taking handfuls at random from about 10 locations and mix them in a clean container. With bunkers or piles, the best method is to remove silage from multiple locations in the face using a loader or silage facing tool, and then subsampling from the removed material. Grabbing samples by hand from the exposed face greatly increases the risk of being trapped in an avalanche, particularly as the sizes of bunkers or piles increase.
When Should Forage Be Sampled?