The process of making hay transforms freshly cut grasses or legumes into a preserved forage source for livestock, which is especially important for feeding animals during seasons when fresh pasture is unavailable. Baling is the mechanical act of compressing this dried forage into a manageable form for transport and long-term storage, maximizing storage density, minimizing spoilage, and simplifying the handling and distribution of the feed. This entire sequence is highly dependent on favorable, dry weather conditions to ensure the quality and safety of the final product.
Preparing the Forage for Baling
The first step involves cutting the forage, typically using a mower or a mower-conditioner. Mower-conditioners are often preferred because they crush or crimp the stems, breaking the waxy outer layer and accelerating the drying process. This conditioning is especially important for thick-stemmed legumes like alfalfa, allowing the stems to dry at a rate closer to that of the leaves.
After cutting, the plants begin the curing process in the field, where they lose moisture through natural evaporation. To promote uniform drying and prevent mold development, the cut material is often spread and fluffed using a machine called a tedder. This action exposes the lower layers to the sun and air, significantly speeding up the moisture loss.
Once the hay is mostly dry, it is gathered into continuous rows called windrows using a rake. The windrows are sized to match the intake width of the baler, ensuring a consistent feed rate for the next stage. This raking also serves as a final opportunity for the hay to cure slightly more before baling begins.
The most precise step in preparation is achieving the correct moisture content before the baler enters the field. If the hay is too wet, it risks developing mold, losing nutritional value, and potentially igniting due to microbial activity and heating during storage. Conversely, if the hay is too dry, the leaves become brittle and shatter during baling, leading to significant nutrient loss since the leaves contain the majority of the protein.
The ideal moisture content for baling is typically between 15% and 20%, but this range varies depending on the type and size of the bale. Small square bales can tolerate a slightly higher moisture level, up to around 20%, while large round or large square bales should be baled at or below 18% moisture for safe storage. Farmers use an electronic moisture probe inserted deep into the windrow to obtain an accurate reading and determine the perfect time to begin baling.
Operating the Baler and Forming the Bale
Baling equipment is classified into two main types: square balers and round balers. Square balers produce rectangular bales and operate continuously, using a plunger mechanism to compress the hay before a knotter system ties the bale with twine or wire. Round balers roll the hay into cylindrical bales; the hay is rolled inside a chamber until the desired density is reached, at which point it is wrapped with twine or net wrap to maintain its shape. Unlike square balers, the operator must stop momentarily to wrap and eject the bale, making the process less continuous.
To ensure consistent bale density, which affects storage stability and forage quality, the operator must drive the tractor in a serpentine or weaving pattern. This technique ensures the baler’s pickup head constantly feeds material from the edges of the windrow into the center of the compression chamber. Maintaining a consistent ground speed that matches the flow of hay is also important, preventing the baler from clogging or producing poorly formed bales.
The choice between baler types depends on the operation’s scale and handling capabilities. Square bales are lighter and easier to handle manually, making them popular for small operations. Large round bales are heavier, often exceeding 1,000 pounds, and are more efficient for large-scale production, requiring mechanized equipment for handling.
Handling and Storing Finished Hay
Once the bale is fully formed, tied, and ejected from the baler, it must be safely removed from the field. Small square bales are often collected manually or with bale accumulators, while large round or square bales require specialized equipment like tractor-mounted spears or grapples for transport. Quick removal is necessary to avoid re-wetting from dew or rain and to prepare the field for the next cutting.
The primary concern in storing hay is preventing moisture absorption and excessive heating. Storing hay indoors, such as in a barn or shed, offers the best protection against weather, preserving the nutritional value and preventing spoilage. If stored outside, bales should be placed on a well-drained surface, like gravel or pallets, to prevent wicking moisture from the ground.
Hay that is baled with higher than recommended moisture content is at risk of spontaneous combustion. This risk arises from microbial respiration within the bale, which generates heat as bacteria consume plant sugars. If this internal temperature rises above 130 degrees Fahrenheit, chemical reactions begin, producing flammable gases that can eventually ignite the hay.
Proper stacking and ventilation are also necessary to manage any residual heat. Stacks should allow for some airflow, and the hay should be monitored for internal temperature for up to six weeks after baling, which is the period when heating is most likely to occur. Detecting a distinct musty or caramel odor is a sign of internal heating, requiring immediate temperature monitoring to prevent a fire.