State 1
Savannah

This is the reference or diagnostic community for the site. The description is based on early range site descriptions, clipping data, professional consensus of experienced range specialists, and analysis of field work.

Characteristics and indicators. This ecological state consists of native grasses and forbs with a scattered mosaic overstory of Oak trees. The total canopy coverage of tree species is typically 10-30%. Herbaceous community is dominated by sand bluestem and little bluestem.

Resilience management. This reference ecological state has evolved through periods of drought, fire, and grazing. Changes in the frequency and severity of these disturbances have altered the plant communities on many sites.

Community 1.1
Tallgrass Savannah (Reference Community)

This plant community is the representative plant community for this site. The major plants are tallgrasses with a scattered overstory of trees. Big bluestem, Little bluestem, Indiangrass and switchgrass are the dominant grasses. Secondary grasses include purpletop, sand lovegrass, sand dropseed, and Canada wildrye. Post oak, blackjack oak and various hickory species are the major trees. These trees form an overstory canopy averaging 10 to 30% percent across the landscape. This site supports a large number of forbs and legumes that make up the balance of the plant community in various species amounts. Major legumes include leadplant, Virginia tephrosia, and native lespedezas. More abundant forbs are Maximillian sunflower, hairy sunflower, fringeleaf ruellia, dayflower, and several species of goldenrod. Over the years this plant community was maintained by periodic fires and herbivory. The following plant list and production data will be reviewed and amended as necessary throughout this ecological site project as more data is collected and historical data is validated.

Resilience management. This community can be maintained with proper grazing management and periodic fire at a return interval of less than five years.

Community 1.2
Midgrass Savannah

Within this community phase, the more palatable tallgrasses and forbs have decreased. They have been replaced by species such as tall dropseed, silver bluestem, and sideoats grama. The less palatable annual forbs, such as broomweed and western ragweed have increased also. Total herbacious production may remain the same as the reference community, however, the composition has been altered significantly.

Resilience management. As long as fire or alternative brush management is continued, this community may persist.

Pathway 1.1A
Community 1.1 to 1.2

Tallgrass Savannah (Reference Community)

Midgrass Savannah

Continuously grazing above carrying capacity without adequate rest may push the plant community to 1.2 Midgrass Savannah. This pathway may also lead to a reduction in fuel which could also negatively impact the effectiveness of prescribed fire.

Pathway 1.2
Community 1.2 to 1.1

Midgrass Savannah

Tallgrass Savannah (Reference Community)

With adequate growing season rest from grazing, the plant community may begin to shift back to phase 1.1. The length of grazing deferment is dependent upon severity of previous grazing events and precipitation patterns.

State 2
Woodland

This vegetative state is composed of an overstory of trees and shrubs that will slowly eliminate most herbaceous vegetation from the plant community if left unchecked.

Characteristics and indicators. The major species are post oak and black jack oak elm and hackberry. Litter has increased due to increased leaf production and often exceeds one inch deep. Herbaceous plants are sparse and limited to shade tolerant species.

Resilience management. There is a high potential for encroachment by eastern redcedar in this ecological state if proper management is not applied. The longer the time since fire, the more mesophication occurs. This process can further hinder restoration to the reference state.

Community 2.1
Tree/Shrub Dominant

This plant community is composed of a moderately closed tree canopy with an understory of tallgrasses and midgrasses. The absence of fire has allowed post oak and blackjack oak to increase in abundance. The overstory tree canopy is closing and now ranges from 50 to 70 percent. The shading and competition for moisture from trees has resulted in a decrease in herbaceous understory plants. Little bluestem is now the dominant grass. Other grasses include big bluestem, Indiangrass, switchgrass, purpletop, purple lovegrass, Scribner’s panicum, Texas bluegrass and Canada wildrye. More abundant legumes are lespedezas, tickclovers, prairieclovers, trailing wildbean and American deervetch. Hairy sunflower, Fendler’s aster, wildbuckwheats, fleabanes and goldenrods are the more common forbs. Shrub species such as buckbrush, smooth sumac, greenbrier, dewberry and vines including poison ivy and Carolina snailseed are common in the understory. To restore the site to near historic conditions would require an extended plan of proper grazing and prescribed burning. Some mechanical or chemical brush control may be needed to facilitate the process.

Community 2.2
Closed Canopy Woodland

This plant community is characterized by oak trees closing the overstory canopy to 70 to 85 percent. Understory vegetation production is greatly reduced and composed almost entirely of shade tolerant grasses, forbs, shrubs and vines. Post oak and blackjack oak are the dominant species. Grasses and grasslike plants are sparse and include Scribner’s panicum, Virginia wildrye, sedges, nimblewill muhly, fringeleaf paspalum, little bluestem, broomsedge bluestem and purpletop. Major forbs include goldenrods, pussytoes, fendler’s aster, blackeyed susan, snake cotton and showy partridgepea. Woody plants in the understory include greenbrier, buckbrush, dewberry, beautyberry, eastern redcedar and chittamwood. Eastern redcedar is beginning to seriously invade the open areas of the savannah. Forage production for cattle grazing is very limited. Deer, turkey and small mammals utilize this site for cover and will benefit seasonally from acorn and berry production. To restore this community to near historic conditions requires a management plan including herbicide or mechanical brush control treatments, accompanied by a prescribed burning and prescribed grazing. When heavy stands of eastern redcedar or greenbrier occur in the understory a combination of control treatments is required. When the oaks are controlled with herbicides, cedar and greenbrier are released and flourish unless other control measures are employed. As redcedar reaches a height of six feet or more, control usually requires some form of mechanical means. Cedar, six feet or less in height, can often be controlled with fire. In most situations remnant tallgrasses and midgrasses are present in sufficient numbers to provide recovery following brush control treatment. Grazing deferment immediately following treatment application is essential to assure recovery of the desired plants.

Pathway 2.1A
Community 2.1 to 2.2

Without fire or brush management, the woody species will continue to encroach, resulting in a shift to community phase 2.2.

Pathway 2.2A
Community 2.2 to 2.1

Implementation of prescribed fire or brush management can reduce the woody species canopy and shift the plant community back towards 2.1.

State 3
Converted

This state is the result of a change in land use. Native vegetation has been tilled and crops or introduced perennial vegetation has been planted.

Characteristics and indicators. This state is often planted to weeping lovegrass or bermudagrass.

Resilience management. Sites in this state are often maintained as open pasture through mechanical or chemical brush management. Without these measures, woody species may encroach on the site.

Community 3.1
Cropland/Tame Pasture

The deep sand savannah site can support a variety of introduced grasses and commodity crops. Through land clearing and tillage these sight may be quite productive crop or pasture fields. As with any tillage system, proper precaution should be taken to limit soil erosion.

State 4
Eroded

This state is the result of wind erosion over bare soil. These areas are often referred to as blowouts.

Characteristics and indicators. Most of the "A" horizon of the soil profile has been displaced.

Resilience management. The remaining subsoil is very low in fertility. Some native grasses and forbs will persist in this state, however, production is greatly reduced.

Transition T1A
State 1 to 2

If fire is removed from the ecosystem, woody species may encroach and begin to dominate the ecological processes on the site. These processes include the water and nutrient cycling and energy flow. Once this occurs, the site has transitioned to the woodland state.

Constraints to recovery. The threshold for this transition is estimated to occur as the woody species increase beyond 40% canopy cover. Common woody invaders include Eastern Redcedar, Hackberry, and Elm. The longer the time since fire, the more mesophication occurs. This process can further hinder restoration to the reference state.

Transition T1C
State 1 to 3

These sites were sometimes cleared and cultivated by homesteaders in the early 20th century. Once the site is cultivated, soil properties are altered and it transitions to the converted state. These alterations affect soil hydrology, chemistry and biota.

Constraints to recovery. Some may still be in cultivation. However, many have been replanted to bermudagrass or weeping lovegrass for pasture use. Although many communities are quite resilient to disturbance, mechanical soil disturbance greatly alters soil structure, chemistry and biology. Returning to the pre-cultivation state may not be feasible for a long period of time.

Restoration pathway R2A
State 2 to 1

Implementing a brush management plan that includes mechanical thinning and the use of prescribed fire can restore the woodland state to an open canopy savannah state. This removal of woody canopy can allow for the restoration of the hydrology, energy and nutrient flow of the reference state.

Transition T4A
State 3 to 4

If this ecological site is subjected to soil disturbances such as land clearing, ripping, or plowing that leave large amounts of exposed soil, the site may become very susceptible to water erosion.

Constraints to recovery. Once the "A" horizon has been displace through erosion, this site has transitioned to an Eroded Sate.