What's better?: Pasture vs. hay field grasses
Question: We purchased 10 acres and plan for part of it to be pasture, while the rest we want as a hay field. Can we use the same grasses for both purposes?
Answer: Unfortunately, it is not ideal to use the same grasses for both purposes. Pasture forage species need to withstand the stress of frequent grazing, regrow quickly, and have good ground cover; therefore, a “sod-forming” grass is necessary as a component of any pasture mixture. In many cases, this sod-forming grass is Kentucky bluegrass. UMN research has shown that a mixture of Kentucky bluegrass, perennial ryegrass, endophyte-free tall fescue, and timothy resulted in a nutrient dense, high yielding, persistence, and preferred pasture for horses.
Kentucky bluegrass is a lower growing, sod-forming grass and therefore tends not to yield as much as other grasses. Because of this, Kentucky bluegrass is not recommended as a grass for a hay field. Hay fields are not under grazing pressure and therefore do not need a sod forming grass. Instead, grasses that grow more upright are ideal for hay fields. There are many potential mixtures for grass hay fields, but one common mixture in the upper Midwest includes orchardgrass (8 to 10 pounds per acre) and smooth bromegrass (10 pounds per acre). Orchardgrass and smooth bromegrass are taller grasses that tend to yield well with multiple cuttings each year. The forage nutritive value of these grasses are also similar to other cool-season grasses when harvested at a similar maturity.
One point of consideration is the minimum suggested hay field size of 5 acres. This is due to a combination of the investment in equipment needed to harvest hay, yield potential of grasses, the time required to harvest hay, and the practicality of needing larger spaces for ease of equipment use.