The amount of pasture needed to sustain livestock depends upon where you live and the amount of forage available. As you can imagine, a pasture in the Midwest is not going to look the same as a pasture in the arid Southwest.
In general, no matter the livestock species, each animal is going to eat roughly 2½ to 3 percent of its body weight in food every day. A 1,000-pound cow or horse will need 30 pounds each day for a maintenance diet—the amount would be higher for a breeding animal or performance horse. This 1,000 pound example is a definable number called an “animal unit.” So two 500-pound cows or 200 5-pound chickens equals one animal unit. You could also say each 100 pounds of live weight is equivalent to 1/10 animal unit. You can use this as a general rule when deciding on the number of animals that are sustainable on your farm. A rule of thumb for productive pastures is 2 acres per animal unit. This provides you with a starting point.
Each animal will have diet preferences, so you’ll get different grazing patterns. Horses and cattle prefer lush growth, whereas goats are browsers. Manage the pasture with some sort of rotational grazing plan, letting some parts of the acres rest for at least 14 days after grazing. If you fail to rest the pasture or you’ve overstocked it with too many animals, there will be too much demand on the forage, the animals will consume it quickly and not allow it to regrow, and you’ll end up with a dirt lot.
Even if you’re doing all the right things, you may still have to augment with hay, especially in your non-growing season.
—Susannah Hinds, USDA National Resources Conservation Service grazing land specialist in Crawfordsville, Ind.
This article originally appeared in the March/April 2011 issue of Hobby Farms.
About the Authors: Sharon Biggs Waller is an award-winning writer and author of Advanced English Riding (BowTie Press, 2007). She lives on a 10-acre hobby farm in northwest Indiana with her husband, Mark, 75 chickens, two Lamancha goats, two horses, and an assortment of cats and dogs. Dr. Lyle G. McNeal is a livestock specialist in the Department of Animal, Dairy and Veterinary Sciences at Utah State University.