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 mans 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 mans 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, TWRAs 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 Bachelors 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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