– first published in the December 2025 issue of The Equiery
As winter approaches, horse owners face the challenge of ensuring they have enough high-quality hay to keep their horses well-nourished throughout the cold months. Ordering hay can be tricky, especially when assessing its quality and determining how much to purchase for the season. Poor-quality hay can lead to digestive issues and other health concerns, while ordering too much or too little can create logistical headaches. This article will guide you through the key steps in evaluating hay quality—considering factors like maturity, leafiness, odor, and color—and provide tips on how to estimate the right quantity to order, ensuring your horses are properly fed without overstocking or running short.
Hay Quality
There’s more to determining hay quality than just color and smell. You’ll also want to inspect your bales for the plants’ stage of maturity, leafiness, and for any foreign materials.
Maturity, or the plant growth stage at which the hay was cut and harvested, is a key indicator of quality, as it affects nutritional value, particularly in grass hay. Compared to mature plants, younger plants have less fiber and are more digestible. Grass hay should be cut before flowering, so quality hay should have no seedheads present. Alfalfa starts to drop in quality the more blossoms that develop, so you’ll want there to be buds but no (or very few) blossoms in your alfalfa hay. Another marker of nutritional value is the leaf-to-stem ratio. 70% of hay protein, 90% of vitamins, and 60% of total digestible nutrients (TDN)[1] are found in the leaves, so you’ll want more leaves than stems in your hay. For active horses, a high leaf-to-stem ratio is crucial, as it represents a higher energy value.
Odor and color are the more commonly known signs of quality. Good quality hay should smell freshly cut, rather than musty or rotten. Green is the ideal hay color, and shows that the hay has been cured properly, whereas hay damaged by rain or overheating during storage will turn brown or even black. Yellow hay can be deceiving, as it has a couple of causes—either the plants were over-mature when cut, or the hay has been bleached by the sun. Sun-bleached hay will be green on the inside of the bale, and should not be judged as critically as other color factors.
It’s also essential to check for foreign materials and the hay’s overall condition. Foreign materials can be injurious (poisonous plants, wire, nails) or non-injurious (weeds, sticks, grain straw). Hay should also not be dusty or contain must or mold. Look for insect and disease damage as well.
Hay Quantity
To calculate your horse’s hay needs, you’ll need to take into account their body weight, bale type, and feeder. Horses generally consume around 2% of their body weight in hay daily. Hay can also be lost depending on how it’s stored and fed. Storage waste from keeping bales outside can range from 5-35%, while storing hay inside can reduce that value by as much as two-thirds. Waste from feeding methods can vary based on the type of feeder used. Square bales fed in a hayrack can have around 5% waste, while square bales fed on the ground with no feeder can have 13% waste. Round bales fed in a restricted-access feeder can have between 5-11% waste, while using no feeder can waste as much as 57% of the hay.[2]
For an example calculation, we’ll use one 1,000-pound horse fed square bales in a hayrack feeder from December 1-March 31. We’ll assume the bales are stored inside and have 5% storage waste.
- 1 horse at 1000 lbs x 2% body weight = 20 lbs hay per day
- 20 lbs x 121 days = 2,420 lbs hay per horse
- 2,420 lbs x 1.05 (storage waste) x 1.05 (ground waste) = 2,668 lbs hay per horse
- 2,668 lbs hay / 40 lb square bale = 67 bales per horse for 121 days
Being able to assess hay quality and calculate the appropriate amount to order can be a big help in saving money while ensuring your horses receive high-quality nutrition. Contact your local University of Maryland Extension office for more information.
[1] University of Maryland Extension. (n.d.). Evaluating Hay Quality [Fact Sheet]. Wvuextension.wvu.edu/files/d/331ea7a0-1911-4ffa-b3ef-9991969f3f1a/evaluating-hay-quality-univ-md.pdf
[2] Crowl, E. (2021, April 7). Calculating your horse’s winter hay needs. University of Maryland Extension. UmdCalculating Your Horse’s Winter Hay Needs
