Understanding Cool-season Grasses

Cool-season Grasses Selection

Cool-season grasses create the forage/feed foundation of most beef cattle operations and a growing percentage of dairy operations in the U.S. and Canada. The forage that grows in your pastures and hayfields is your cheapest source of feed.

There are many species of cool-seasongrasses, and each has advantages. Under most conditions in the Midwest, Pacific Northwest (under irrigation), northern Plains, upper South (Kentucky, Tennessee, Virginia) and Northeast, the best overall forage grasses are perennial ryegrass (including festulolium), orchardgrass, tall fescue (endophyte free), timothy, and, in some places, meadow brome (when available, not to be confused with smooth brome). Those varieties offer the best combination of forage quality, persistence, yield potential and extreme weather tolerances. The oversimplified advantages of each are:

Annual Ryegrass: Up to the I-80 corridor, annual ryegrass can be an excellent option for  winter pastures or early-season spring haylage harvests. It is very high forage quality can produce great yields.

Orchardgrass: This species offers a great combination of longevity, forage quality, yield, and heat and drought tolerance. It has a great reputation among all livestock and horse markets.

Perennial Ryegrass: Although short-lived, forage perennial ryegrass does have the advantage of containing very high levels of sugar, which results in excellent animal performance.

Tall Fescue: Tall fescue offers the best overall heat and drought tolerance of the cool-season grasses. Endophyte-free varieties lose a little of that heat and drought tolerance, but it’s still good. Endophyte-free products have above average forage quality and can last for many years. Endophyte-infected varieties can be very hardy and still be used for forage, but they are toxic to animals and have to be managed very carefully. It’s rarely recommended.

Timothy: A short-lived perennial, timothy can produce good yields and good forage quality. It has a great reputation in some markets. It is especially suited for well-drained soils and is a favorite in areas with irrigation.

Meadow Brome: A very cold-tolerant, long-lived perennial, meadow brome provides very good forage quality and is probably underused in the forage industry. However, seed production is limited and supplies are often short.

Other grasses have their own niche markets, such as forage Kentucky bluegrass, smooth brome, various wheatgrasses, and others. More information on these species is found on this website.

Cool-season Grasses Management Tips

Increase Seeding Rates for Pastures: Researchers claim that when cows are grazing they take about the same number of bites per day (around 35,000) regardless of how much forage they get with each bite. Therefore, it makes sense that the denser the forage stand, the more forage a cow will get in each bite, and the more forage it then digests, and the more weight it will then add or more milk it will produce. Furthermore, a denser stand produces plants with thinner stems, which increases the quality of the stand. For example, if you were planting a pure stand of tall fescue for pasture, plant 30-35 lbs/acre. If the field was for hay production, then you just need to plant 25 lbs/acre.

pH Matters: A field with a soil pH of 6.5 will usually far out-yield the same field with a pH of 5.5. Always keep in mind that low pH prevents plants from utilizing a huge percentage of the nutrients in the soil. Therefore, a large percentage of fertilizer applications are wasted. If your pH is under 6.0, it can be more beneficial to spend your money on lime that year rather than fertilizer (do both if you can, but if not, choose lime first).

Invest in Fertilizer: Fertilizer more than pays for itself (many times over), especially if your soil pH is adequate for optimum growth.

Mix It Up: Mixed stands add genetic diversity to the field, reducing the effects disease of outbreaks that may only affect one species, and can prolong the season for high-quality grazing/harvests. With mixed stands, each species comes out of dormancy and matures at different times, preventing the entire stand for maturing (going to seed) at the same time.

Add Some Legumes: Mixing legumes in a pasture or hayfield certainly has positive effects. Alfalfa, red or white clover can increase the forage quality of a grass stand and deposit nitrogen in the soil, which assists in better grass production.


Forage Grass Characteristics

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