By Aaron Berger
Accurately sampling and testing hay is the only way to get a real understanding of the nutritive value of feed. Using values from previous years or a “book value” can be costly since a producer may incorrectly develop a feeding plan using inaccurate information. When sampling hay, getting a representative sample is a critical first step. Samples must accurately represent the entire lot of hay. Previous Nebraska Extension guidance states that a “lot” of hay should be harvested from the same field consisting of similar types of plants, cutting dates, maturity, variety, weed contamination, type of harvest equipment, curing methods and storage conditions.
Hay samples should be taken using a hay probe or a core sampler. The hay probe should penetrate at least 12-18 inches into the bale and have an internal diameter of at least 3/8-inch. Avoid getting hay probes hot when using a drill to drive the probe into the bale, since friction from high speeds can heat the probe to a point where it damages the hay sample.
To get a representative hay sample from a “lot” of hay, select 15-20 bales in the lot. Once all the samples for a “lot” have been collected, the samples may need to be sub-sampled to get the feed down to a size that can be sent in for analysis. The Nebraska Extension NebGuide G331, “Sampling Feeds for Analyses,” walks through a step-by-step process for this.