All Grass Types Are Divided
Into Two Catagories

There are thousand of grass species in the world, but all species can be divided into two grass types: Warm season grasses and Cool season grasses. Except for a few species, most grasses within these two grass types will come in only two colors: green and tan. Green when it is growing and tan or straw colored when dormant. Depending on where you live, you may have observed in early spring that many lawns have areas of green grass mixed together with areas of stray colored, dormant grass. The dormant grass will generally emerge from dormancy and green up in late April or May, but you may have wondered why they don't green up at the same time.

The growth habits of the two grass types are different. The group's names indicate the different temperature ranges that the grasses thrive best in. Cool season grass types start growing in early spring and will thrive in temperatures from 65 to 75 degrees. Warm season grass types emerge from dormancy in late spring and thrive in temperatures from 80 to 95 degrees. It is built into the plant's genetic structure to begin growth at specific soil temperatures.

All warm season grasses lose chlorophyll in the fall and turn from green to tan. Cool season grass types will often remain a shade of green through the winter.

A view of two grass types

The image below was taken in mid-winter. It is a field that receives no care during the year except for mowing. It shows a mixture of straw colored, warm season grass as well as green, cool season grass scattered throughout. The birds, like those shown, are responsible for depositing seeds of many different grasses and weeds.

List of common cool season grasses

The following is not an exhaustive list, but contains some commonly used cool season lawn grasses. More detailed descriptions and uses of these grasses can be found in the Cool Season Grass section of this site.

• The fescues- There are two groups of fescue grass: fine fescues and coarse fescues. Originally, tall fescue (coarse fescue) was developed for field use as a forage crop, but many fine bladed varieties have been developed for turf use. Be sure to look for bags with "Turf Type" fescue printed on it. The fine fescues originated in Europe and are primarily marketed as "shade grass" in the U.S.
• Bluegrass- The two basic types are common bluegrass and improved bluegrass varieties. The common or "public" variety is best used on sites that receive only occasional fertilization because of disease problems. Improved varieties of bluegrass are the better choice if the site is receiving regular fertilizer treatments.
• Ryegrass- Perennial and annual types. Annual ryegrass has a one year life cycle and will need to be reseeded each year. Both types are often used for overseeding dormant warm season grasses in fall. It is also used in seed mixtures because of fast germination and quick establishment. Some varieties of perennial ryegrass form quality turf.
• Bentgrass- Creeping bentgrass is most often used on putting greens because it tolerates low mowing necessary for a putting surface. It is considered a high maintenance turfgrass and rarely used by homeowners.
• Brome, Timothy, and Orchard Grass are field grasses that are sometimes found in home lawns, but generally will not produce a quality turf. They are often used in roadside seed mixtures.

Common warm season grasses

Warm season grasses are the choice of many in warmer climates. Many grasses within this group spread by "runners" and can easily fill in injured areas. For detailed information about each of these grasses, look in the Warm Season Grass section. Examples of common warm season grasses include:

• Bermudagrass- It has common and improved varieties and is the most commonly used warm season grass. It grows wild in many lawns and can be invasive if it is not wanted. It can also become a thick, quality turf when properly maintained. The uses of the improved varieties range from golf greens and fairways, to home lawns. One of the disavantages to bermudagrass is that it has very poor shade tolerance.
• Zoysiagrass- This grass has its origins in the Orient. It makes a thick turf and can be started from plugs, seed or sod. Seed is expensive and slow to establish. It has become a popular grass in the transitions zone.
• St. Augustinegrass- Commonly used in the south from Florida and along the Gulf Coast states as far as Texas. It doesn't have the cold tolerance of Bermudagrass so it is restricted to the south. It is almost always established by sod or plugs.
• Centipedegrass- It is not as widely used as the other warm season grasses, but is on the increase. Range is from Florida along the Gulf coastal regions as far as Texas.
• Kikuyugrass-It is used as turfgrass, but only in the tropics and is considered a weed in the U.S. It is one of the fastest spreading grasses and can be extremely invasive. It will cover over shrubs, fences, light poles and will displace other grasses. It is not recommend.
• Buffalograss- Blue-green in appearance. It is native to the arid prairie regions of the U.S. For that reason, it is often used in arid areas because of its lower water requirements. Improved varieties can make excellent turf grass.