When to test. Not all hay necessarily needs to be tested annually. “Producers who can fairly accurately estimate the quality of hay based on previous testing or many years of monitoring cow condition won’t necessarily need to test hay, as long as it is compared to hay harvested at about the same maturity from the same field or pasture,” Larson said.

Buying hay? Typically much less is known about purchased hay compared to raised hay. Off-farm hay should almost always be tested prior to purchasing.

What to test for. Nutritionist Phillip Lancaster said it is beneficial to evaluate hay that is newly acquired. “When testing, there are two main things to look at on the report: the amount of protein and some estimate of digestibility,” Lancaster said. “Total digestible nutrients [or TDN] will help us know how much energy is in the hay, and that is the nutrient that cattle need in the greatest quantity.”

Sample correctly. Veterinarian Brad White added that it is important to get a correct sample of the hay when testing. “You don’t have to test every bale, but you do need to get a representative sample from the cuttings. For guidelines on how to properly collect the sample, reach out to the local county Extension office,” White said.