Forage is the foundation of a horse’s diet. It includes any plant-based feed that is high in fiber, whether grazed fresh from a pasture or preserved as hay, haylage, or silage. Horses evolved as grazing animals, and their entire digestive system is built around processing large volumes of fibrous plant material. Most horses need forage equal to 1.0 to 2.0 percent of their body weight per day, meaning a 1,000-pound horse should eat roughly 10 to 20 pounds of forage daily.
Why Forage Matters for Horses
The horse’s digestive tract is designed to extract energy from plant fiber through a process called hindgut fermentation. When a horse chews forage, it produces saliva that helps buffer stomach acid. The fibrous material then moves through the stomach and small intestine before reaching the cecum and large colon, where billions of microbes break it down. This fermentation produces fatty acids that the horse absorbs and uses as a direct energy source. It also generates B vitamins, biotin, and essential amino acids as byproducts.
Forage does more than provide calories. The physical act of chewing keeps a horse occupied for hours, which aligns with its natural behavior of grazing 14 to 18 hours a day. The fiber and saliva produced during chewing help maintain a healthy stomach pH. Without enough forage, horses face a higher risk of gastric ulcers, and prolonged fasting periods can trigger repetitive stress behaviors like cribbing or weaving. Fiber in the hindgut also acts as a fluid reservoir, holding water in the intestinal contents and releasing it as the fiber is fermented, which supports hydration.
Pasture Grasses
Fresh pasture is the most natural form of forage. The grasses that work best depend on your climate. In temperate regions, cool-season grasses dominate: Kentucky bluegrass, perennial ryegrass, tall fescue, orchardgrass, timothy, and smooth bromegrass are all common choices. Kentucky bluegrass is one of the most abundant species in horse pastures because it keeps its growing points underground, making it resilient to grazing pressure. Tall fescue handles both trampling and dry conditions well, while orchardgrass establishes quickly and tolerates frequent grazing better than timothy or smooth bromegrass.
Legumes are often mixed into pastures to boost protein and improve soil nitrogen. White clover is the most popular legume for horse pastures because it tolerates frequent grazing. Red clover is sometimes used but many horse owners avoid it because it can cause excessive drooling from a compound called slaframine. Alfalfa grows well in drier areas and is significantly higher in protein and calcium than grass species. A common pasture seed mix in the northeastern United States contains Kentucky bluegrass, endophyte-free tall fescue, and white clover.
Hay: The Most Common Preserved Forage
Hay is forage that has been cut, dried, and baled for storage. It is the staple forage for horses that don’t have access to adequate pasture, particularly in winter months or in areas with limited grazing land. The most widely fed types include timothy hay, orchardgrass hay, and alfalfa hay. Grass hays like timothy and orchardgrass typically contain 10 to 16 percent crude protein, while legume hays like alfalfa range from 16 to 22 percent. Younger, leafier cuttings are more digestible and energy-dense. As forage plants mature, their stems accumulate more cellulose, hemicellulose, and lignin, reducing both digestibility and nutritional value.
Quality matters enormously. When evaluating hay, look for a high leaf-to-stem ratio, fine stems, and large intact leaves. Good hay has a green color, indicating it was cured under favorable conditions, and smells like fresh-cut grass. Hay that looks brown, smells musty or like tobacco, or shows visible mold was likely baled too wet and should be avoided. Ideal baling moisture is between about 15 and 20 percent. Below 15 percent, leaves shatter and fall off during handling. Above 20 percent, the bale can develop mold or even heat enough to pose a fire risk.
Haylage and Other Preserved Options
Haylage is forage that is cut earlier than traditional hay and baled at higher moisture content, then wrapped in plastic to ferment. Compared to hay, haylage tends to be lower in sugar and water-soluble carbohydrates but higher in crude protein and fat. Its energy and fiber content are similar to hay on a dry matter basis. Haylage can be a good option for horses with respiratory issues because it produces far less dust than dry hay, though it must be fed quickly once a bale is opened to prevent spoilage.
Forage Alternatives
Sometimes hay is unavailable, too expensive, or a horse simply can’t chew it well enough due to dental problems. Several alternatives can fill the gap, provided they contain at least 18 percent crude fiber to qualify as a roughage source.
- Hay cubes: Compressed blocks of chopped timothy, alfalfa, or a blend of both. They offer consistent fiber and protein content and can be soaked in water for horses with poor teeth. Hay cubes work well as a supplement or substitute, though they don’t provide a fully balanced diet on their own.
- Beet pulp: A byproduct of the sugar beet industry, available as shreds or pellets. It is highly digestible, very low in starch and sugar (under 10 percent), and promotes healthy hindgut bacteria. Shredded beet pulp may provide fiber long enough to partially mimic the chewing benefits of hay, making it especially useful for senior horses.
- Complete feeds: Pelleted or extruded feeds formulated to replace both hay and grain in a single product. These are designed for horses that cannot eat long-stem forage at all, often due to severe dental disease or age-related chewing difficulties.
Forage and Metabolic Health
Not all forage is safe for every horse. Pasture grasses can accumulate high levels of non-structural carbohydrates, including simple sugars, starch, and fructan. In some conditions, these can reach over 40 percent of the grass’s dry matter. For horses with insulin resistance, equine metabolic syndrome, or a history of laminitis, this is a serious concern. High sugar intake from forage can trigger or worsen laminitis, a painful and potentially debilitating inflammation of the tissue connecting the hoof wall to the bone inside the foot.
Horses at risk typically benefit from having their forage tested for sugar and starch content. Soaking hay in water for 30 to 60 minutes before feeding can leach out some of the soluble sugars. Limiting pasture access during times when sugar levels peak, generally on cool sunny afternoons or during periods of frost followed by sunshine, is another common management strategy. Hay samples with lower non-structural carbohydrate levels, confirmed through lab analysis, give owners the most reliable information for building a safe feeding plan.
How to Feed Forage Effectively
Because horses are designed to eat small amounts almost continuously, the way you provide forage matters nearly as much as the type you choose. Feeding two large meals a day leaves long gaps with an empty stomach, which increases the risk of ulcers and behavioral problems. Slow feeders, which use a net or grate to restrict how quickly a horse can pull out hay, extend feeding time significantly. Horses have to take smaller bites and work longer to consume the same amount, which mimics natural grazing patterns. This not only reduces boredom but also helps stabilize blood sugar and insulin levels by moderating the rate of intake.
Splitting your horse’s daily hay ration into three or more feedings, or using a slow feeder for free-choice access, keeps forage moving through the digestive system more steadily. For horses on pasture, rotational grazing helps maintain grass quality and prevents overgrazing of preferred species. Allowing pastures to rest and regrow keeps root systems healthy and ensures the forage your horse eats remains nutritious throughout the grazing season.