Estimating Winter Hay Needs

As the summer comes to an end, our warm season pastures, such as bermudagrass and bahiagrass, will begin declining in both production and quality.  This is the time of year when horse owners should begin stocking up on hay to feed through the fall and winter months while pastures are dormant.  Although it is a large bill to front, buying all your horse’s hay now is typically cheaper than waiting until November or December to buy hay that has been stored in a barn and when hay supply is getting low.  Some hay producers will often sell at a discounted rate if you buy bales straight out of the field.  I would consider this a benefit for both a producer and customer since labor is reduced (accumulating bales, stacking them on a trailer, and unloading into a hay barn or shed is labor intensive) and customers can usually get a dollar to two discount per square bale.  

There are several things to consider when stocking up on hay for winter feeding.  First, how much hay does your horse consume per day, specifically when there is little standing forage available in the pasture?  Horses vary on how much they eat but a good rule of thumb is 2 percent of their body weight per day. Multiplying 2 percent by your horse’s weight will give you their daily intake. For example, a 1000-pound horse will consume about 20 pounds of hay per day.  Again, this may fluctuate but 2 percent is a good starting point.  

Next, multiply daily intake, 20 pounds in this example, by the average number of days you feed until pasture green-up.  Let’s say your pastures are dormant from November to April.  That’s roughly 150 days multiplied by 20 pounds.  In this scenario, total forage consumption for the winter is around 3,000 pounds per horse. Research has shown that around 5 percent of hay purchased will not make it to your horse's mouth so let's take that loss into account. You will lose around 150 pounds of the 3,000 pounds which brings our total to 3,150 pounds to compensate. 

Now, how many bales does that translate into? Both large round bales and small square bales vary in their density which affects their weight. Finding a hay producer with consistent bales is very important in estimating how many you will need.  Let’s assume you feed square bales and they average 50 pounds. Take your total hay needed for the winter (3,150 lbs) and divide by average bale weight (50 lbs).  Your horse will need 63 square bales to get through the winter.   

After you calculate how much hay your horse needs, you also need to think about storage space.  Hay should be stored out of the weather.  Bales that get rained on become a great environment for molds to develop which can adversely affect your horse so make sure you have the room to keep them dry.  Nutrition quality also drops as hay is exposed to the elements throughout the winter. Generally, square bales are easier to store in smaller areas such as an empty stall. A 12-foot by 12-foot stall with an 8 -foot roof should hold around 90 square bales, depending on how you stack them.  If you have several horses and need to feed round bales, they can be set on wood pallets and covered with tarps to keep the moisture out. 

If you have the storage capacity, purchasing all your hay before supply runs low in the winter is a good practice to keep feed costs down.  Always remember that all hay is not created equal so consider having your hay tested for nutrient content to ensure your horse’s nutrition requirements are being met.  If you have any questions about horse nutrition or forages please contact your local Extension office.