The number of alfalfa bales harvested from an acre is highly variable. Alfalfa yield is measured by weight (tons per acre), not by the number of packages created. To determine the actual bale count, one must first establish the total weight of hay produced per acre. This total weight is then converted based on the specific bale type, size, and density used during baling.
Understanding Alfalfa Yield in Tons Per Acre
The standard measurement for alfalfa production is tons per acre (TPA), which represents the total dry biomass harvested annually from the field. Alfalfa yield ranges widely, depending primarily on management intensity and the growing environment. In dryland operations, where the crop relies solely on natural rainfall, annual yields commonly fall between 2 and 3 tons per acre. Yields fluctuate significantly based on precipitation patterns.
Fields under intensive management with irrigation, however, demonstrate substantially higher and more stable yields. Irrigated production often yields between 6 and 8 tons per acre. Some high-yield regions and specialized systems report annual harvests exceeding 10 tons per acre.
Converting Hay Weight into Bale Counts
The physical number of bales derived from a ton of hay is entirely dependent on the type of baling equipment used, which dictates the bale’s size and density. Common alfalfa bale types include small square, large square, and large round bales, each having a distinct average weight.
Small square bales, often favored for manual handling and horse owners, typically weigh between 50 and 75 pounds. In contrast, large square bales can weigh from 800 to 1,500 pounds, requiring specialized machinery for transport. Large round bales generally range from 1,000 to 1,500 pounds.
The density of the hay inside the package, influenced by the baler’s settings and moisture content, also affects the final weight. Alfalfa hay tends to be denser than grass hay, contributing to a slightly heavier bale for the same volume.
To calculate the number of bales per acre, a farmer must divide the total annual yield in pounds by the average weight of a single bale. For example, a 6-ton per acre yield converts to 12,000 pounds of hay. If this hay is packaged into small square bales averaging 60 pounds each, the acre would yield 200 bales (12,000 lbs ÷ 60 lbs/bale). Using the same 12,000 pounds of hay in a large round bale averaging 1,200 pounds, the yield drops to only 10 bales per acre (12,000 lbs ÷ 1,200 lbs/bale).
Environmental and Management Factors Influencing Yield
The total annual tonnage harvested is determined by a combination of environmental conditions and specific farming practices. Water management is a significant factor, as alfalfa requires 20 to 46 inches of water per season for peak production. Irrigated systems can produce two to three times the yield of dryland farming because they eliminate water stress.
Soil health and fertility are also important, as alfalfa requires a near-neutral soil pH, ideally between 6.5 and 7.0, for optimal growth. Deficiencies in macronutrients like potassium and phosphorus can substantially reduce biomass produced. Farmers apply fertilizer based on soil testing to replace the nutrients removed with each ton of hay.
The length of the growing season and the cutting frequency directly impact the final yield. Warmer climates allow for more cuts, increasing the total annual tonnage. Aggressive cutting schedules, while yielding higher quality hay, can sometimes result in a lower total seasonal yield. Furthermore, wheel traffic from multiple harvests can damage alfalfa crowns, leading to reduced stand persistence and lower yields in subsequent years.