Hay is a feed product often confused with a specific plant, like wheat or grass. It is not a single plant species but a processed agricultural product.
Hay: A Prepared Feed, Not a Plant Species
Hay is dried forage, primarily utilized as animal feed. Its production involves cutting herbaceous plants, then carefully drying and storing them. This drying preserves nutritional content and prevents spoilage from microbial growth due to high moisture. For example, hay baled with moisture levels between 17% and 22% can heat significantly, leading to spoilage. Properly cured hay, with 20% or less moisture, can be stored for months.
Grasses as Primary Components of Hay
Many types of grasses form the foundation of most hay production. Common examples include timothy, orchardgrass, fescue, and ryegrass. These grasses are well-suited for hay due to their growth habits and nutritional value when harvested at the appropriate stage.
Timothy hay typically contains 7% to 12% crude protein, favored for its low protein, high fiber, and moderate calorie content, making it easily digestible for animals like horses and cattle. Orchardgrass offers higher protein (10-12%) and calorie content than timothy, with a balanced calcium to phosphorus ratio.
Tall fescue is another widely used grass, known for its deep root system and adaptability to various soil types, providing good year-round production. It typically contains 8-14% crude protein and moderate energy.
Perennial ryegrass is valued for its fast growth and high yield, making it a flexible option for hay production, particularly in temperate climates. Harvesting grasses at the correct maturity stage is important; cutting too late can decrease protein content and increase fiber and lignin, reducing digestibility and nutritional value.
Wheat and Other Plants in Hay Production
While wheat is botanically a type of grass, it is primarily cultivated for its grain. However, immature wheat plants can be harvested to produce wheat hay. This is typically done when the plant is in the boot to early head-emergence growth stage to maximize nutrient content, particularly for livestock requiring higher nutrient density. If harvested later, such as at the milk stage, yield may increase, but the hay’s quality will be lower, and the presence of stiff awns in mature wheat can cause oral irritation in cattle. Wheat hay can offer protein levels ranging from 13.5% to 13.7% on a dry matter basis when cut early.
Wheat hay is less common than hay derived from dedicated forage grasses or legumes, and its nutritional profile differs. Beyond grasses and wheat, other plant types are also used for hay, most notably legumes like alfalfa and clover. Alfalfa hay, for example, is known for its higher protein content, typically ranging from 15% to 21%, and elevated calcium levels compared to grass hay. Legumes are often mixed with grasses to create a balanced feed, providing a comprehensive nutritional spectrum for livestock.