Hay is forage—grasses, legumes, or other herbaceous plants—that has been cut and dried for later use as animal feed or bedding. Haymaking preserves the nutritional value of a fresh field crop by rapidly reducing its moisture content. This preservation provides livestock with a consistent source of energy and protein when fresh pasture is unavailable, such as during winter or drought. Successful hay production requires a coordinated sequence of steps to minimize nutrient loss and prevent spoilage.
Selecting the Right Time to Harvest
The most significant factor determining hay quality is the crop’s maturity stage at cutting. As forage plants mature, digestible energy and protein decrease while less digestible fiber increases. For peak nutritional value, legumes like alfalfa should be harvested between the late bud and early bloom stage. Grasses, such as timothy or orchard grass, should be cut when they are in the boot stage, just before the seed head fully emerges.
Haymaking also depends on securing a suitable weather window. The goal is to dry the crop from about 80% moisture down to 15–20% for safe baling. Producers must confirm a minimum of three to five consecutive days of sunny, dry weather with low humidity and a consistent breeze. Rain on cut hay leaches out soluble carbohydrates and proteins, significantly reducing the feed value.
Necessary Machinery and Setup
Transforming a standing crop into a dense, storable bale requires several specialized pieces of equipment. The process begins with a mower-conditioner, which cuts the forage and simultaneously crimps or crushes the stems. This conditioning step breaks the waxy outer layer of the stem, allowing it to dry at a rate closer to the thinner leaves.
A tedder may be used, particularly in humid environments, to lightly spread and fluff the material across the field. The tedder’s action increases the hay’s exposure to the sun and air, promoting faster and more uniform drying. This tool must be used carefully to avoid shattering the fragile leaves of legumes.
The hay rake gathers the dried forage from the wide swath into a narrow, continuous windrow. The windrow is shaped and sized to feed directly into the baler, ensuring the final bale has a uniform density. Finally, the baler compresses the hay and securely ties it for handling and storage.
Mowing, Conditioning, and Curing
The initial mowing height affects both the crop’s drying time and its ability to regrow quickly. For alfalfa, the recommended stubble height is typically 2 inches, while cool-season grasses require a higher cut of 3 to 4 inches to protect carbohydrate reserves. Cutting the forage in the mid to late morning, after the dew has evaporated, maximizes the initial drying rate.
The conditioning process helps the entire plant dry uniformly by overcoming the difference in drying rates between thin leaves and thick stems. This mechanical action reduces the time the hay must remain in the field, which minimizes the risk of weather damage and nutrient loss.
The curing, or drying, phase is the longest and most weather-dependent part of haymaking, requiring the hay to lose over 60% of its moisture content. Monitoring the moisture level daily is essential. The tedder may be used to turn and aerate the windrows when the moisture content is still high, ideally above 40%. Turning the hay at this moister stage minimizes leaf shatter, preserving the most nutrient-rich part of the plant.
Final Steps: Baling and Storage
Baling must be timed precisely to capture the hay at the ideal moisture content, typically between 15% and 20% for safe storage. Baling below 15% moisture causes excessive leaf loss, especially with legumes. Baling above 20% increases the risk of mold growth and heat generation from microbial activity. If moisture exceeds 25%, this heat can lead to spoilage and spontaneous combustion.
The baler’s settings for density are critical for long-term preservation. A tight, dense bale, generally exceeding 10 pounds per cubic foot, sheds water better and limits oxygen penetration, which fuels microbial activity. For round bales stored outside, using net wrap or plastic film offers superior protection against weathering and moisture absorption compared to traditional twine.
Proper storage is the final step in protecting the harvested feed. Hay should be stored in a well-drained location, ideally inside a barn or shed to prevent rain exposure. If outside storage is necessary, bales must be elevated off the bare ground using pallets or crushed rock to prevent wicking of soil moisture. Storing bales with space between rows and maximizing air circulation further minimizes the risk of spoilage.