Section 2: Native and Introduced Grasses
Introduction
Native grasses have had thousands of years to adapt to various
Texas climates and soils and they offer a definite advantage in
highway right of way environments. Texas is a diverse state with
varying climates and vegetative regions, so there is a definite
need for selected introduced species of grasses to be included in
our seed mixes to ensure quick vegetation coverage and to prevent
erosion on the rights of way. Native grasses will prevail eventually,
covering and stabilizing the right of way. Benefits of native grasses
include:
- excellent erosion control when established and maintained properly
- long lived (up to 100 years)
- excellent wildlife habitat (food and cover)
- highly resistant to invasions of noxious weeds
- low maintenance costs
- well adapted to Texas soils and climates
- resistant to agricultural chemical runoffs
- aesthetically pleasing
- part of our natural heritage.
Establishment and Growth
Native grasses are usually slow to establish and plantings
may appear to have failed after the first growing season. Although
the inspector may see weed-infested areas with only spindly and
scattered individual grass plants, the stand is probably well on
its way to becoming established. There are several reasons for this
slow establishment:
- Native grasses commonly have more extensive root development than above-ground growth during the first year.
- Many native grasses do not begin growing until late spring or early summer, making their first year growing season short.
- A stand of native grasses generally requires about three years to reach maturity. Once native grasses become established, however, very few weeds can compete with them for essential nutrients and water in the soil. At maturity, native grasses may have a fibrous root system extending to a depth of five feet or more.
Maintenance
To reduce competition from weeds after planting, mow sites
planted with native and introduced grasses in late fall at a height
not less than seven inches.
On slopes where mowing is not appropriate, herbicides may
be used to control competing weeds.
Erosion Control and Soil Stabilization
With their deep, fibrous root systems, established stands
of native grasses provide excellent long term erosion control and
soil stabilization. Because the root systems of native grasses extend deeper,
they can obtain access to essential soil moisture that shallower
rooted introduced grasses cannot. This allows native grasses to
grow on poorer soils and resist drought.
Wildlife Habitat
Many of the game birds, songbirds, deer, rabbits and other small mammals that play an important role in the natural heritage of Texas depend on established stands of native grasses for nesting cover, den cover and food. Properly maintained highway rights of way covered with native grasses provide highly productive wildlife habitats. Research indicates that unmowed roadsides with native plant cover support two to three times the number of bird nests as those that are mowed annually.
Many species of birds and mammals depend on roadsides during at least a part of their life cycle. The following table shows some of the species that will benefit from rights of way planting with native grasses intermixed with wildflowers.
Birds | Birds | Mammals | Mammals |
|---|---|---|---|
Ring-necked Pheasant | Dickcissel | Deer | Harvest Mouse |
Bobwhite Quail | Mourning Dove | Coyote | Cotton Rat |
Scaled Quail | Lark Bunting | Cottontail Rabbit | Ground Squirrel |
Meadowlark | Horned Lark | Blacktailed Jackrabbit | Least Shrew |
Scissor-tailed Flycatcher | Several species of sparrow | Whitefooted Deer Mouse | Gopher |