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Department of Environment and Conservation


The Return of Native Grasses to Tennessee
By
Andrea Brewer Shea

Once, the American West totaled 700 million acres of grassland or prairie.

Today, less than one percent of these extensive grasslands remain in North America. Large grazing animals, such as bison, elk and antelope, were once found in great numbers roaming throughout the grassland region. As the native grasslands have diminished, so have all the species that have depended on them for existence: birds, insects, butterflies, prairie grasses and wildflowers.

Prairies have become covered with corn, wheat, soybeans, grazing cattle, houses and factories.

The bison disappeared from east of the Mississippi by 1800, almost becoming extinct. Early settlers controlled wild fires, allowing the prairies to succeed to forests. The deep, well-drained soils were plowed and European forage grasses were planted for cattle. Lands were overgrazed and erosion began. The forage grasses could not grow back fast enough, more grass was planted and the cycle continued.

Other non-native grasses traveled by way of hay and manure from Europe. The beauty and diversity of the grasslands were not enough to save them from almost total destruction.

After a major climatic warming about 10,000 years ago, grasslands, or prairies, began to extend into Tennessee and became interspersed with oak-hickory forests throughout the west and central regions of the state.

Early settlers arriving in Tennessee and Kentucky found large, open, grass-dominated, treeless areas that they called "barrens." These prairie-like lands resembled the tallgrass prairie regions in the Great Plains and were dominated by native grasses such as Big Bluestem, Little Bluestem, Indian Grass, and Switchgrass.

The term "barrens" has been used by ecologists locally to include scrub forests, thickets, savanna and woodland with grassy understory.

According to Dr. Hal DeSelm, retired botany professor at the University of Tennessee, the barrens in Tennessee are related by their dominant plants to prairies of the west and north, but are unique in that they have strong local and southern plant relationships.

DeSelm has spent his botanical career studying and inventorying barrens. He has found that barrens are associated with glade openings (cedar glades) in cedar stands on shallow soil over limestone in Middle Tennessee, with open sandstone on the Cumberland Plateau, and in deeper soils in the Ridge and Valley.

The barrens, like the tallgrass prairies to the west, were most likely maintained by fires intentionally set by Native Americans, by lightning fires and grazing or trampling by herds of herbivores such as bison, elk and deer. The grasslands were very important to the Native Americans for food grains, grazing, and for hunting.

The usefulness of grasses is thought to have played an important role in man’s evolution and domination of the world. Most civilizations developed in the grassland regions of all the continents. Grasses have provided man with a major food source, shelter and essential material for clothing and housing.

Grasses inhabit the earth in greater abundance than any other group of plants. Adapted to every extreme of climate types, they cover almost one-third of the area of the earth and about one-half of the area of the United States. The domestication of native grasses began at least 10,000 years ago in three independent areas of the world - the Near East, South and Central America and North America. The grains of grasses from these regions, such as wheat, rice, corn, barley, rye, and oats, were found to provide a staple food supply for the human race and are major crop plants today.

Rice, originating in Asia, feeds more people in the world than any other plant product. Wheat, barley, rye and oats originated in the Near East. Corn originated in Mexico and South America and spread into North America during prehistoric times. Maygrass, a wild grass, was cultivated in North America at least 6,000 years ago.

Because of man’s manipulation, most of these grass crops do not exist in the wild. Their origins are buried in antiquity, with little evidence remaining of their ancestors.

The economic importance of grasses is not only as a direct food source for man, but as an indirect consumption of grains through animal products. Cattle, sheep and swine graze in pastures of grasses, their primary food source.

The prairies and barrens that occur in Tennessee today are considered remnants of a very important ecosystem. These grasslands are a high priority for protection by state and federal agencies as designated natural areas. May Prairie in Coffee County, Roan Mountain in Carter County, Couchville Cedar Glades in Davidson County and Vesta Glades and Barrens in Wilson County are a few examples.

Fort Campbell Military Reservation contains one of the largest and intact barren systems in Kentucky and Tennessee.

On Roan Mountain in the Blue Ridge, there is a different type of grassland called "balds," open grass and sedge covered mountaintops adjacent to spruce-fir forests.

There is a current trend to conserve and restore these remnants by converting the non-native Fescue Grass pastures back to the native grass pastures that existed before them.

There are currently about three million acres of Fescue Grass planted in Tennessee. Fescue was introduced from Europe during the late 1800s. Kentucky 31 Fescue has become the predominant grass variety used in the last 50 years. Serious ecological problems are being recognized as a direct result of this introduction. Other plants cannot compete with this short, quick-spreading grass creating a monoculture with no diversity of grasses or other plants. Fescue limits movement and provides little cover for wildlife. It has also proven to be poor quality for livestock grazing.

Since 1989, Tennessee Wildlife Resources Agency (TWRA) has been promoting the restoration of barrens or prairies through the planting of native warm season or bunch grasses such as Big Bluestem, Little Bluestem, Indian Grass, Switchgrass and others. These grasses do most of their growing in the summer, hence the term "warm season," and grow in deep-rooted clumps or "bunches." Fescue and other introduced grasses growing in the spring are called "cool season" grasses and have shallow root systems.

According to Mark Gudlin, TWRA’s small game program coordinator, native grasses are good conservation choices. They are good for soil erosion, soil building and water purification, are drought tolerant and do not require fertilizer. The benefits to wildlife are great. Growing up to eight-feet-high and in bunches, native grasses allow animals and birds to move freely, provide good nesting cover and brood areas, and offer a variety of food sources from seeds and insects. Native wildflowers have room to grow in the spaces also providing food and shelter.

In areas where native grasses have been established, there has been significant increase in game animals, such as deer, quail, turkey and rabbits. Non-game animal diversity increases as well. Prairie dog, fox, and coyote are associated with grasslands. Birds include prairie chicken, hawks, owls, meadowlarks, sparrows, especially the Henslow Sparrow, a declining migratory bird. Grasses and associated sedges and rushes growing in marshes and swamps provide food for migratory birds including ducks and geese.

Private landowners are finding that native grasses invite a great variety of birds and butterflies to nest and feed.

Mark Goins, the caretaker of a farm owned by Dan Evins, CEO for Cracker Barrel Old Country Store, has been turning hundreds of acres of fields of Fescue and Sericea Lespedeza into native grasslands with great success. Goins maintains the grasslands by burning and states that he alternates burning in different sections to prevent destroying the eggs or chrysalides of the butterfly and other beneficial insects. Wildlife need refuge, so different fields are left fallow some years. He is aware of habitat needs for other wildlife that he lures to the property. In addition to flowers, butterflies need puddles with wet sand or mud on which to perch and drink because they cannot drink from open water. He mows a space on the edge of farm ponds to keep them muddy for butterflies.

Native grasses offer a great benefit to livestock. The nutrient value is higher, the cost for fertilizer or pest control is minimal, and the hay production is greater.

TWRA is promoting the return of native grasslands through the Upland Game Bird Habitat Program. They help provide seeds or seedlings and offer a cost share incentive to the private landowner. Many public lands, such as wildlife management areas, are being converted.

At this time, the seed sources for these plantings are coming from the northern and Midwestern states. It is hoped that in the near future, seeds from the native Tennessee barrens will be harvested to maintain pure native stock.

What are Grasses?

Grasses are very basic plants with a root, stem and flower.

They are monocots, having the vascular tissue of the stems in scattered bundles. Grasses have simple linear leaves with sheathing or clasping bases, parallel veins and entire margins. The stems are round and have joints at the nodes. The leaves are clustered at the base with up to 15 joints in the first inch of the stem becoming farther apart as they progress up the stem. The leaves have two main parts, the sheath and the blade. The sheath clasps around the stem and the blade extends outward.

Being wind-pollinated and wind-dispersed, they need no bright colors, fragrances, or nectar to attract insects for pollination. The flowers are small and inconspicuous with the petals and sepals reduced to basic lobes of tissue. The flowering part, situated at the end of the stem, is called the inflorescence. This flower cluster is made up of smaller units called spikelets. Spikelets are made up of florets enclosed by leaf-like structures called the "palea" and the "lemma." The number of florets can be one to 30 or more. The one-seeded fruits are bony or hard and are called grains.

Grass identification is intimidating even to the expert botanist. The basic way to identify grasses is to look for differences in height, shape of leaves, nodes on the stems, hairiness, flower types and appendages on the florets such as bristles.

For a quick reference or identification, determine whether the plants are cool season grasses or warm season grasses.

Cool season grasses complete their cycle before hot weather begins. They are sod-forming, with short branching rhizomes, and include many non-native grasses such as Bluegrass, Fescue, Bromegrass, Timothy, Red Top, Wheat, and Barley. Warm season grasses bloom from June through September and complete their growth cycle in late summer or fall. Examples include native species such as the Bluestem grasses, Grama grasses, Indian Grass, Switchgrass and Love Grasses.

Secondly, distinguish them by growth stature: tall, medium, and short. The prairie grasses, such as Big Bluestem, Indian Grass Switchgrass and Eastern Gamagrass can grow from four to eight-feet-tall. Little Bluestem, Sideoats Grama, Wild Rye, and fescues grow from two-to-four-feet-tall. Shorter grasses, less than 18 inches tall, are usually mat-forming. These grasses, typical of lawns, pastures and golf courses, are Bermudagrass, Bluegrass, and Crabgrass.

Native Tennessee Grass Species

There are a total of 51 native grass groups in Tennessee. The major ones are:

Agrostis, Alopecurus, Andropogon, Aristida, Arundinaria, Bouteloua, Brachyelytrum, Bromus, Chasmanthium, Cinna, Danthonia, Digitaria, Echinochloa, Elymus, Eragrostis, Erianthus, Glyceria, Hordeum, Leersia, Melica, Muhlenbergia, Panicum, Paspalum, Phalaris, Poa, Schizachyrium, Sorghastrum, Sphenopholis, Sporobolus, Stipa, Tridens, Tripsacum, Vulpina, Zizaniopsis.

Some Native Grasses Used For Wildlife And Landscaping

Wild Rye Grasses - Elymus canadensis, E. virginicus. The many members of this group have coarse bristles on the dense flowers that resemble wheat. The leaves appear early in spring but the flowers do not bloom until July - August. The fruits turn a golden color as they ripen and persist through the winter. Bottlebrush Grass, Elymus hystrix, has wide spaces between each flower and the long stiff bristles look just like a bottlebrush.

Wild Oats - Chasmanthium latifolium. The open flowers hang down from long stalks giving the same appearance as Sea Oats, a close relative. Wild Oats is a good choice for landscaping, but it can be aggressive.

Eastern Gamagrass - Tripsacum dactyloides (comes from Greek work finger). This warm season grass is commonly used in prairie restoration. Tripsacum is the only grass other than corn that has separate male and female flowers, and, is considered as a possible ancestor of corn.

Big Bluestem, Turkey Foot - Andropogon gerardii. The plants can grow up to eight-feet-tall with fuzzy flowers radiating from the top of the stem. Amazing colors are displayed throughout the summer and fall, from steel gray-blue in the summer to brown, red and purple in the fall. One of the dominant plants of the tallgrass prairie, Big Bluestem is especially useful as a forage plant.

Little Bluestem - Schizachyrium scoparium. Probably the most abundant native grass, Little Bluestem is present in 90 percent of the states. The plants are smaller than Big Bluestem and the flowers are located up and down the tan, brown and wine-red branches.

Broomsedge - Andropogon virginicus. The flower stalk of Broomsedge is tucked inside the leaves with silvery white hairs surrounding the flower. The plant is very coarse and turns bronze-orange in the winter. It is leafier than other grasses, but is not a good forage grass for livestock.

Sideoats Grama - Bouteloua curtipendula. Sideoats Grama is a warm season grass used in prairie restoration. The flower clusters are arranged mainly on one side of the stem, hence the name "sideoats," and are purplish in late summer.

Hair Grass - Deschampsia flexuosa. A beautiful ornamental, this delicate grass has wiry basal leaves that last throughout winter. The plant is silvery and wispy with the early flowers bronze or purple then turning tan or silver.

Switchgrass - Panicum virgatum. Growing up to seven-feet-tall in big leafy clumps, Switchgrass is a dominant, warm season prairie grass. The pyramid-shaped flowers are born singly on the end of branches and the flower clusters persist throughout the winter providing shelter for animals when it snows.

Indian Grass - Sorghastrum nutans. The small twisted bristles on the flowers are showy on the narrow flower head. Indian Grass can grow up to eight-feet-tall and is a dominant of the tallgrass prairie. The fruit, about six to 10 inches long, appears as copper-colored plumes.

River Cane - Arundinaria gigantea. The only native bamboo in Tennessee, River Cane is somewhat woody, forming extensive stands by spreading rhizomes. It is good cover and food for wildlife. Do not confuse this with the Oriental bamboo, a non-native that is extremely aggressive!

Tips on Planting Native Grasses

Do not dig plants from the wild. Collect and plant grass seeds that are native to Tennessee. Be careful not to collect more that 10 percent of the seeds in an area.

Most seeds are ready about one month after the plant has finished blooming. Dry the seeds in a paper bag and plant them in the fall deep in the soil.

The prairie mixes sold by many nurseries contain alien invasive grasses and other wildflowers and should not be planted in Tennessee. The worst invaders of natural areas include Bachelor’s Buttons, Dames Rocket, Yarrow, Ox-eye Daisy, Shasta Daisy, Crown Vetch, Cosmos, White and Yellow Sweet Clover, Crimson, Red, and White Clovers, California Poppies, annual Phlox, and many more. Please contact a local native plant nursery for a selection of native prairie seed sources.

Native grasslands and "meadows" may appear as weeds to many; be reminded to check ordinances within city limits before converting your manicured lawn into a more desirable and useful landscape. As the prairie plants mature, the undesirable weeds will lessen and beauty will abound.

For information on conversion of pastures to native grasses call Mark Gudlin at TWRA (615) 781-6610.

Call Andrea Shea at (615) 532-0439 for a list of native plant nurseries in Tennessee.

(Andrea Brewer Shea is the Rare Species Protection Coordinator with the Tennessee Department of Conservation.)

Updated September 1, 1999; Send comments to Department of Environment and Conservation.


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