How Much Pasture Does a Horse Need? Grazing Recommendations

Could you tell me how long a horse that gets 2 flakes of hay morning and evening would have to be turned out on good pasture to get the same intake?  Thanks! KP, Pennsylvania 

Dear KP, 

I have a short answer for you and a long answer.  I’ll give you the short one first!  According to the sixth edition of the NRC’s Nutrient Requirements of Horses, one study concluded that horses need to graze for 17 hours daily to meet their nutritional needs.  So unless your horse is going to be on pasture 24/7, it doesn’t sound like he’ll be able to meet his forage needs on pasture alone. 

Now let’s explore the long answer.  How much nutrition a horse gets from grazing depends on many things, including:

  • quality of the pasture
  • size of pasture (acres)
  • stocking density (number of horses/acre)
  • species of plants
  • maturity of plants

Chapter 11: Feeding Behavior and General Considerations for Feeding Management even says gender, age, breed and number of horses in the herd grazing all effect the grazing rate.  All sorts of interesting facts are shared in this chapter, such as “pastured horses move a distance of 2.6 to 3km daily, of which 50-60% occurred during grazing” and “Horses are constant feeders.  When grazing, a horse takes a bite of grass, then moves forward one or two steps, followed by another bite.”  By the way, this is NOT how my horse grazes!

There’s also information in this chapter that you probably already know, for example: 

“Infestations of mosquitoes, ticks, horseflies and other external parasites disrupt feeding activities of horses.”


“Adult horses appear to have an aversion to eating grass that has been contaminated by equine feces. (roughs and lawns, parasites)  Horses have been reported to reject pastures where feces have contacted the grass for longer than 24 hours.”

I love that you’re considering putting your horse on pasture and certainly don’t want to discourage you from doing that.  Imagine all those omega 3 fatty acids and all that Vitamin E he will be getting!  Just keep in mind that he may still need supplemented with a flake or two of hay per day.  And don’t forget that even on pasture he is probably not getting his mineral needs met, so supplement with a multi-vitamin/mineral or ration balancer specifically made for grass.  Oh, and always supply clean fresh water and salt (preferably loose, not a block).  Neither pasture nor hay nor grain has enough sodium chloride to meet a horse’s daily requirements.