Estimating Winter Hay Needs

Cooper and Ferris in a snowstorm

Question: We recently purchased a farm and will be housing our two quarter horses over the winter. They are trail horses who are not ridden during the winter. Because I’ve always boarded my horses, I’m not sure how to estimate how much hay I will need for the winter. Can you provide some guidelines?

Response: An adult horse at maintenance will consume between 2 – 2.5% of their bodyweight in feed (hay and grain) each day. For example, a 1,000 pound horse fed a 100% hay diet would consume 25 pounds of hay each day.

  • From October 15 to May 15 (when there is no pasture in MN), the horse would consume about 5,350 pounds of hay or 2.7 tons.
  • This would equal 107 fifty pound small square‐bales or six 900 pound round‐bales during this time.
  • For two horses, this amount would be doubled; 214 small squarebales or 12 round‐bales.
  • It is critical to know the weight of the hay bales; not all bales weigh the same.

If the same horse was receiving 5 pounds of grain each day, their hay needs would be reduced to 20 pounds each day.

  • From October 15 to May 15 the horse would consume about 4,280 pounds of hay or 2.1 tons.
  • This would equal 86 fifty pound small square‐bales or five 900 pound round‐bales during this time.
  • For two horses, this amount would be doubled; 172 small‐square bales or 10 round‐bales.

These estimates assume good quality hay is fed in a feeder to reduced hay waste. When feeding small squares‐bales, hay waste when a feeder was not used (hay fed on the ground) was approximately 13% compared to only 1 to 5% when a feeder was used. When feeding large round‐bales, not using a feeder resulted in 57% hay waste compared
to 5 to 33% hay waste when a feeder was used. Its always best to purchase some extra hay since horses may require additional hay during the cold winter months (depending on their access to shelter).

Author: Krishona Martinson, PhD, Univ. of Minnesota. Reprinted with permission of the author. For other topics from the Univ. of Minnesota Equine Extension, visit their website.

8 Replies to “Estimating Winter Hay Needs”

  1. I heard that you should not feed rye grass to horses because it is higher in sugar than any other grasses, also fescue should not be fed to brood mares or any sex of horse just not a good choice of grass hays, what is your opinion

    1. Hi Mary,

      Thank you for your questions about rye grass and fescue for horses.

      Perennial rye grass may be infected with an endophyte that produces an alkaloid, lolitrem B, that causes rye grass staggers. Endophyte free ryegrass is quite suitable for horses and is quite palatable and nutritious. The sugar content will vary with the maturity of the hay. The less mature the hay, the higher the sugar content. Early vegetative might be 5-6% sugar and early bloom drops to 3-5% sugar. If you are feeding horses that have metabolic issues, I would recommend having the forage tested.

      Tall fescue that is endophyte infected should not be fed to broodmares, particularly in the last 1/3-1/2 of gestation as it produces an alkaloid, ergovaline, that can cause a number of reproductive issues with prolonged gestation, thickened placentas and failure to produce milk being common. It is the endophyte that produces the toxin, not the grass itself. It can also slow down growth in young horses. Endophyte free tall fescue is available and can be used w/o restriction. Unfortunately, the endophyte infested fescue seems to be a bit more hardy than the endophyte free fescue and may come back in a pasture that was treated and reseeded with endophyte free fescue. Testing is available to determine the status of the forage, which is recommended if you are uncertain of the type of fescue, particularly with broodmares or young horses.

      Best wishes,

    1. Hi Margie – Great question. The 1.5% is the recommendation for forage. 2 – 2.5% is the total feed – so can be all hay, or a combination of hay & grain, depending on the specific caloric needs of each horse.

      Hope that helps clarify! Thank you ~ Gina T.

  2. Feeding hay in the winter months can be just a tricking as feeding hay in the summer months with founder prone horses. Weeds, or high fescue seeds in broan grasses can be high in surgar starches, it is best to try to get your hay from the same hay provider. Unfortanely many can not do this as they buy hay as they need, This makes it a little tricker and one has to really fine tooth each bale to make sure no strange weeds or to much seeds or flowers and clovers are in a bale. It will only take a small portion of this to just give a horse a stomache ache and possible colic, it is best to go with less is best in this case if you have to feed this kind of hay.

    1. Hi,
      Thanks for your question! Can you share a few more details on what conditions are like for your region in the winter, how they compare to your spring and summer months and feeding resources during those times?


      1. I live in North Mississippi, I start feeding hay about the last week of October through the end of March. I am just going to deduct the month of April and May from the previous calculation.

Leave a Reply

Your email address will not be published. Required fields are marked *