The best hay for most sheep is a good-quality grass hay, with alfalfa or a grass-legume mix reserved for ewes and lambs that need extra protein and energy. There’s no single “best” hay for every sheep at every stage. A dry ewe maintaining her weight has very different nutritional needs than a ewe nursing twins, and the wrong choice can cause real health problems in rams and wethers. Matching hay type to your animals’ current stage is the key decision.
Grass Hay: The Everyday Foundation
For adult sheep at maintenance, including dry ewes, rams outside of breeding season, and wethers, grass hay is the safest and most practical choice. It supplies around 10% crude protein and enough digestible energy to keep a mature sheep in good condition without the excess calcium that comes with legume hays. Timothy, orchardgrass, and smooth bromegrass are the three most common options, and each has trade-offs worth knowing.
Timothy is the most palatable grass hay for sheep. They consistently prefer it over other grasses, and it’s easy to find in most regions. The downside is that timothy fields produce less tonnage and tend to thin out after three to five years, which can make it slightly more expensive.
Orchardgrass establishes quickly, recovers fast after cutting, and produces more forage in late summer and early fall than any other cool-season grass. The catch is maturity: when orchardgrass gets overly mature at harvest, sheep will pick around it and waste a significant portion. If you’re buying orchardgrass hay, look for fine stems and a soft feel rather than thick, coarse stalks.
Smooth bromegrass makes excellent hay because two-thirds of its growth comes in May and June, perfectly timed for a single hay cutting. It’s less ideal as a sole pasture grass because regrowth is slow, but as dried hay it’s a solid, reliable option.
When Sheep Need More Than Grass Hay
Protein and energy demands spike at two points in a ewe’s year: late gestation and early lactation. A ewe carrying twins or triplets in her final four weeks of pregnancy needs roughly 35% more crude protein and noticeably more energy than a maintenance diet provides. During the first six to eight weeks of nursing twins, those demands stay just as high. Grass hay alone can’t meet these needs without significant grain supplementation.
This is where alfalfa and mixed hays earn their place. Alfalfa hay averages about 17% crude protein, clover hay around 15%, and a 50/50 grass-legume mix sits near 13%. For ewes in late gestation or peak lactation, alfalfa or a grass-alfalfa mix provides the protein boost they need, often reducing the amount of grain you have to add.
For lambs being introduced to solid feed, alfalfa is the standard recommendation. The classic creep-feeding combination is cracked corn paired with fine-stemmed, leafy third-cutting alfalfa. Alfalfa can make up 20 to 40 percent of a creep-feed mixture, and its high protein supports the rapid growth lambs need in their first two to five months.
Why Alfalfa Can Be a Problem for Rams and Wethers
Alfalfa is high in calcium relative to phosphorus, and that imbalance creates a real risk for male sheep. When the calcium-to-phosphorus ratio in the diet skews too high, it promotes the formation of urinary stones, a painful and sometimes fatal condition called urinary calculi. Research has confirmed that diets with elevated calcium-to-phosphorus ratios and high alkalinity significantly increase stone formation in sheep.
Rams and wethers are the most vulnerable because their narrow urinary tract makes even small stones dangerous. If you’re keeping wethers as pets or fiber animals, or maintaining rams outside of breeding season, grass hay is the safer long-term choice. When alfalfa is the only hay available, balancing it with a phosphorus supplement can help, but it’s easier to avoid the problem by sticking with grass hay for these animals.
Clover Hay and Fertility Concerns
Certain clovers, particularly subterranean clover, contain plant compounds called phytoestrogens that mimic estrogen in the body. In the rumen, one of these compounds is converted into a metabolite called equol, which binds to estrogen receptors and can disrupt the entire reproductive tract. The condition, historically called “clover disease,” causes changes to the cervix, irregular estrous cycles, increased rates of stillborn lambs, and uterine prolapse after birth.
Short-term exposure tends to cause temporary fertility problems that resolve once the clover is removed. Long-term exposure is more concerning because it increases the number of estrogen receptors in the ewe’s tissues, making the effects cumulative. Prolonged grazing on estrogenic clover can lead to permanent infertility. While severe clover disease has become rare, subtler fertility issues still show up in flocks grazing estrogenic clover varieties. If you’re feeding clover hay to breeding ewes, keep it as a smaller portion of the diet rather than the sole forage source.
Cereal and Fescue Hay: Know the Risks
Oat and barley hay can be useful, affordable options, but they carry a specific danger: nitrate accumulation. Cereal crops that were stressed by drought concentrate nitrates in their stems and lower stalks, and those levels remain constant once the hay is baled. Nitrate poisoning is one of the more common toxicity emergencies in livestock, and drought-stressed oat and barley hay cause the majority of cases in regions where these crops are fed. Any cereal hay should be tested for nitrate levels before feeding. If levels come back elevated, the hay can still be used by blending it thoroughly with low-nitrate feeds in a mixed ration, but you can’t rely on sheep to self-select between high and low-nitrate hay offered separately.
Tall fescue hay is another one to approach carefully. Most older fescue stands harbor a fungal endophyte that produces compounds toxic to livestock. Sheep tolerate fescue better than cattle do, but they’re still susceptible to reduced feed intake, poor weight gain, weak wool production, heat stress, reproductive problems, and a circulation condition called “fescue foot” that can cause lameness. If tall fescue is your primary hay, look for varieties bred to be endophyte-free, or limit fescue to a portion of the total diet.
How to Judge Hay Quality
The species of hay matters less than the quality of the specific bales you’re feeding. A poorly made alfalfa hay can be worse than a well-made grass hay. The two things that most affect quality are maturity at cutting and storage conditions.
Hay cut at an earlier growth stage has more protein, more digestible energy, and less fiber than hay cut late. You can feel the difference: early-cut hay is soft and leafy, while late-cut hay is stemmy and coarse. If you want to put a number on it, a forage lab will report values for acid detergent fiber (ADF) and neutral detergent fiber (NDF). Lower numbers mean more digestible, more nutritious hay. As a reference point, high-quality alfalfa cut at the bud stage typically comes in around 28% ADF and 38% NDF. For sheep, you don’t need dairy-cow-grade forage, but aiming for ADF below 35% and NDF below 50% will ensure your hay is doing real nutritional work.
A forage test costs very little and tells you exactly what you’re working with. It’s especially worth doing when you’re buying hay from a new source, switching hay types, or feeding ewes in late pregnancy when nutrition is critical.
Mold, Moisture, and Safe Storage
Hay baled at moisture levels above 14 to 15 percent is at risk for mold growth. Moldy hay isn’t just unpalatable. It can harbor organisms that cause listeriosis, a serious and often fatal brain infection in sheep. Listeriosis from contaminated silage and moldy hay is one of the more common infectious causes of death in small ruminants.
When evaluating hay, break open a bale from the center and check for dustiness, a musty smell, or visible white or gray mold. Reject any hay with these signs, especially for pregnant ewes, which are particularly susceptible to listeriosis. Store hay off the ground, under cover, with good airflow between bale rows to prevent moisture from creeping in after purchase.
Matching Hay to Your Flock
- Dry ewes, rams, and wethers: Good-quality grass hay (timothy, orchardgrass, or bromegrass) meets their needs and avoids the calcium excess that causes urinary stones in males.
- Ewes in late pregnancy or early lactation: Alfalfa or a grass-alfalfa mix provides the higher protein and energy their bodies demand, reducing reliance on grain.
- Growing lambs: Leafy, fine-stemmed alfalfa hay paired with a grain source supports rapid growth during the first several months.
- Breeding ewes year-round: Limit clover-heavy hay, especially from estrogenic varieties, to protect long-term fertility.
- Any sheep: Test cereal hays for nitrates, avoid moldy hay entirely, and prioritize early-cut, leafy bales over coarse, stemmy ones regardless of species.