Forage 2025 | Don’t Overlook the Value of Accurate Hay Testing
While a visual appraisal to gauge hay quality can be informative, extension experts stress that there’s only one way to truly know the quality of hay — getting an accurate test.
“Hay that looks nice may not provide the protein and energy that are needed to meet an animal’s nutrient requirements, and hay that is visually unappealing may have better than expected quality and still meet the needs of certain classes of livestock,” said University of Nebraska-Lincoln Beef Systems Extension Educator Aaron Berger. “When sellers, buyers and producers of hay know the nutritive value, they can more accurately value it and also utilize it to meet the needs of the livestock they are feeding cost-effectively.”
The assumption that all hay from a given field or cutting is the same is another issue commonly disproved with testing.
“Hay quality can vary tremendously from one cutting to the next, from year to year and even within a single field,” Berger said.
Specifically, accurate hay testing enables livestock producers to:
- Develop effective feeding plans
- Identify if additional feed supplements are necessary
- Prevent overfeeding high-quality hay, thus avoiding unnecessary expenses
- Optimize rations for different classes of livestock
- Accurately value hay for buying and selling transactions
South Dakota State University Extension Beef Nutritionist Field Specialist Madison Kovarna she said she has never seen a producer regret having a feed test done.
“There are databases out there with average values for nutritional qualities, but they are exactly that — averages,” she said. “Having your own test results in hand will ensure the ration you have is meeting requirements. The insight you gain allows you to make better decisions in both the nutrition of your livestock and hayfield management. Hay sellers can get rewarded for higher quality hay if they have the numbers for the bales they have for sale. Overall, having a slip of paper from the feed lab enables hay producers to get paid for quality and prevents lower-quality hay from being misrepresented.”
Long-term sustainability for livestock
“Having hay testing completed accurately allows you to be more aware of the feed entering a bunk or feeder on your operation,” Kovarna said. “For instance, as we are entering the spring caving season, cows are going to start requiring more feed and high-quality feeds. Their protein and energy requirements increase following calving due to lactation. This directly impacts the calf at her side as that baby is receiving all its nutrients from her milk.”
Being aware of the feed for different livestock needs helps prevent waste and optimizes nutrition:
- Cow-calf. Again, nutritional needs increase for lactating cows, and inadequate feed quality can lead to poor milk production and calf development.
- Feedlots. With high-energy grains being provided and protein accounted for in dried distillers’ grains, liquid supplements, or other feedstuffs, lower-quality forage can often be sufficient since grain-based rations provide most nutrients. This is a reason why some feedlot diets utilize corn stalks for the forage, it is an excellent ‘scratch factor’ for rumen health and can be fairly inexpensive.
- Weaning calves. High-quality hay will go a long way to support young animals during stressful transitions. Calves need high-quality feed put in front of them as during this period of high stress their feed intakes may be subpar. This means you need to get the same level of nutrients into these animals in a much smaller package.
How to ensure accurate hay sampling and testing
Testing is important, but even more critical, proper sampling is essential for obtaining accurate results. Berger recommends following a systematic approach when collecting hay samples:
- Use a hay probe. A probe takes a core sample that captures material from multiple layers of the bale.
- Take a representative sample. Typically, test 15-20 bales per lot, selecting bales from different areas of the field.
- Probe at the correct location. For round bales, insert the probe into the rounded side. For square bales, probe from the middle of the butt end.
- Avoid spoiled material. Remove any outer moldy or spoiled layers before sampling.
Avoid these sampling mistakes
Kovarna said that the biggest mistakes she sees are in the approach — not taking a representative sample, not probing the bale or not probing in the correct location.
Her tips to avoid inaccuracies:
- When deciding which bales to test, try to find ones that come from throughout the field they are harvested from. This may be easier if the cores are collected prior to transporting bales and or stacking them. If the field is not equally represented the results you get back will not be the most accurate values due to the potential of poorer, or higher, quality areas being tested. This also allows you to potentially market bales from various areas of your fields differently depending on the quality.
- For round and square hay bales, it is vital to use a hay probe and in the correct location to capture a small amount from all layers within a bale. For instance, on a round bale, probing the face of a bale instead of the rounded side will only capture material from one layer and can skew the results.
- It is also possible to collect samples from a windrow in the field. In several locations in a windrow cut six-inch sections, with sharp shears. Be careful to avoid losing plant material like leaves during this process.
“Hay testing is not just the livestock producer’s job,” Kovarna said. “Sellers can be rewarded for a high-quality product that they produce. This can also help understand fertilizing strategies, pest management and other decisions impact and develop a production plan that works best for your land and production needs.”
Regional considerations
Nebraska
“Nebraska producers often grow alfalfa and grass/alfalfa mixes,” Berger said. “For these common hay types, near-infrared reflectance (NIR) analysis is the most cost-effective testing method. However, if testing uncommon forages, wet chemistry analysis provides the most accurate results.”
Keep in mind that weather and soil can influence hay quality.
“Hay can be tested any time of the year, but often, testing occurs in late summer and fall before marketing or feeding,” Berger said. “Weather conditions, humidity, and storage methods all impact hay deterioration.”
Overall, he said that producers do have a variety of approaches for getting hay tested.
“Producers who market high-value hay to dairies are very specific and purposeful about getting hay tested because their customers require it,” Berger said. “For producers selling ‘cow hay’ or lower quality hay as a roughage component in a feedyard ration, they may only test for nitrates and crude protein. Testing annual forages for nitrates and a complete hay test analysis will provide the most information.”
South Dakota
“South Dakota’s diverse landscape supports various forage crops, from alfalfa to crop residues,” Kovarna said. “While South Dakota does not have as many irrigated hay fields we see as we move further West, we still have a climate that works well for producing a variety of hay crops. We can see grass, alfalfa, cover crop, crop residue and a variety of other forage products produced here that can be fed to livestock or used as bedding. Because hay production methods and conditions vary, no two hay lots are exactly the same, generally speaking.”
Because of this, buyers need to be aware and use test results to guide purchasing decisions.
“South Dakota and surrounding states offer many feed testing laboratories, allowing producers to shop around for the best fit,” she said. “Additionally, SDSU Extension Regional Centers offer hay probes for rent and educational resources whether you’ve been sampling your hay for years or if this is your first time sending in samples.”
Drought and excessive moisture can create challenges that affect hay quality as well.
“Drought conditions reduce plant growth, limit nutrient mobility and can cause high nitrate levels,” Kovarna said. “Excess moisture, on the other hand, can lead to mold, fermentation and even spontaneous combustion in improperly stored hay.”
Quality understood
“Producers are realizing many benefits of knowing exactly what is going into their animals,” Kovarna said.
For producers, buyers and sellers, understanding the actual quality of hay can mean the difference between optimal livestock performance and costly inefficiencies. An understanding of quality means you can make informed decisions, improve livestock performance, and enhance economic sustainability.
“Hay testing should not be viewed as an unnecessary expense but as a vital investment in overall farm management,” Berger said. “It’s the only way to truly know what the feed value is.”
