State 1
Savannah

This is the Reference state for this ecological site. It represents the historical variability of plant communities on this site under the natural disturbance regime.

Characteristics and indicators. This ecological state consists of native grasses and forbs with an overstory of oak trees. The average canopy coverage of tree species ranges from 15-30%.

Resilience management. This state requires periodic fire every 2-5 years to maintain the relationship between woody and herbaceous species.

Community 1.1
Tallgrass Savannah(Reference Community)

The general aspect of the vegetation is an oak savannah. The major plants are tallgrasses and midgrasses with a scattered overstory of trees. Big bluestem, little bluestem, Indiangrass and switchgrass are the dominant grasses and comprise 50 to 60 percent of the vegetation by weight. Secondary grasses include purpletop, sand lovegrass, purple lovegrass, sand dropseed Canada wildrye and Virginia wildrye. Post oak, blackjack oak and hickory are the major trees. Common species of shrubs are smooth sumac, skunkbush, and leadplant. Combined woody species form an overstory of about 20 to 40 percent. The site supports a large number of forbs and legumes. Major legumes include Illinois bundleflower, sessile tickclover, Illinois tickclover, catclaw sensitivebrier, Virginia tephrosia, slender lespedeza, Stuves’ lespedeza and roundhead lespedeza. More abundant forbs are Maximilian sunflower, hairy sunflower, pale echinacea, fringeleaf ruellia, heathaster and several species of goldenrod. Over the years this plant community has been maintained by periodic fires and moderate grazing.

Resilience management. This community relies on periodic fire every 2-5 years in order to maintain the structure and composition of species. Abusive grazing practices can both alter herbaceous species composition and reduce fuel loads needed for effective use of fire. Without fire, woody species can dominate the site reducing hydrological function and energy flow on the site.

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 They have been replaced by species such as tall dropseed, silver bluestem, and sideoats grama.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 herbaceous production may remain the same as the reference community, however, the composition has been altered significantly. In this community, midgrass species are roughly equal to tallgrass species in composition by weight.

Resilience management. The communities of the reference state are quite resilient. However, without periodic fire, this community may be at risk of transitioning to a woody state. Abusive grazing practices may also contribute to this risk by reducing fuel loads need to produce an effective fire.

Pathway 1.1A
Community 1.1 to 1.2

Tallgrass Savannah(Reference Community)

Midgrass Savannah

Abusive grazing practices which exceed carrying capacity without adequate rest/recovery will result in a quick reduction of tall grass species and palatable forbs. Without some type of rest for these plants, constant defoliation will reduce the vigor creating an opportunity for less palatable plants to out-compete them for resources.

Context dependence.While drought can exacerbate this pathway, it is often grazing that is the main driver.

Pathway 1.2A
Community 1.2 to 1.1

Midgrass Savannah

Tallgrass Savannah(Reference Community)

Through a properly implemented prescribed grazing system that includes a balanced stocking rate and some degree of growing season rest, this community phase may be reverted to the reference plant community. The length of deferment and time required for this restoration is dependent upon length of abusive grazing, precipitation and management system used.

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. Woody species that were historically suppressed by fire have increased. These include hackberry, elms and greenbriar.

Resilience management. There is a high potential for encroachment by eastern redcedar in this ecological state if proper management is not applied.

Community 2.1
Tree/Shrub Dominant

This plant community is a moderately closed oak savannah with an understory of mid and tallgrasses. The absence of fire has allowed woody species to increase in abundance. The overstory tree canopy ranges from 40 to 60 percent. The competition from the increased canopy has led to a decrease in herbaceous understory plants. Little bluestem is the dominant grass in the understory. Other grasses include big bluestem, Indiangrass, switchgrass, purpletop, purple lovegrass, Scribners’ panicum, Virginia wildrye and Canada wildrye. More abundant legumes are slender lespedeza. Illinois tickclover, catclaw sensitivebrier, trailing wildbean and showy partridgepea. Hairy sunflower, heathaster, western ragweed, fleabane and goldenrods are the more common forbs. Woody species that were historically suppressed by fire have increased, including hackberry and elm species. Low growing woody species such as buckbrush, flameleaf sumac, blackberry and greenbriar have increased and are common on the site.

Community 2.2
Closed Canopy Woodland

This plant community is characterized by oak trees and other trees forming an overstory canopy of 65 to 85 percent. Understory vegetation is sparse and composed primarily of shade tolerant grasses, forbs and low growing woody species. Grasses and grasslike plants include Scribners panicum, Virginia wildrye, sedges, arrowfeather threeawn, fringeleaf paspalum, little bluestem, broomsedge bluestem and purpletop. Major forbs include goldenrods, pussytoes, heathaster, blue aster, sageworts, tickclovers, lespedezas and showy partridgepea. Woody plants in the understory include blackberry, buckbrush, eastern redcedar, redbud and seedlings and immature plants of blackjack, post oak, elm and hackberry.

Pathway 2.1A
Community 2.1 to 2.2

Tree/Shrub Dominant

Closed Canopy Woodland

In the absence of fire or brush managment, the trees and shrubs in this plant community will continue to out-compete the herbaceous vegetation for sunlight and resources. With time, it will become a closed canopy woodland community.

Pathway 2.2A
Community 2.2 to 2.1

Closed Canopy Woodland

Tree/Shrub Dominant

Through a program of brush management and prescribed fire, the closed canopy plant community can be reverted to the tree/shrub dominant community. This pathway can be accomplished by opening the canopy and allowing more sunlight to reach the soil surface. Special consideration should be taken if eastern redcedar is present in high amounts in the understory as they will be very competitive once the canopy is opened.

State 3
Grassland

In this state, the shallow savannah has been transitioned to an open grassland dominated by tallgrasses and forbs.

Characteristics and indicators. This state has very low canopy of trees due to chemical and/or mechanical brush management.

Resilience management. Without proper management, this state may return to a savannah state within a short time. It is important to note that maintaining this state will require significant inputs and the transition may take many years. A large number of acres of Sandy Loam Savannah sites have had an attempt at clearing woody species through chemical herbicide use. Mid-century use of 2,4,5-T and other similar chemicals led to large areas of timber kill. However, many of these areas resprouted into thicker and denser "scrub oak" mottes. More recently, tebuthiuron pellets have been used in attempts to open up more grazable acres for cattle production. Some have had success, however, many times the canopy release leads to secondary invasions by eastern redcedar, sericea lespedeza, and broomsedge bluestem. Careful planning and consideration should be used before attempting chemical application in the cross timbers.

Community 3.1
Tallgrass Dominant

This community is dominated by tallgrass species such as little bluestem, big bluestem, switchgrass, and indiangrass. Some perenial forbs may persist, depending on the herbicide used on the oak trees. Grazing management plays a key role in the maintenance of this plant community. If tebuthiuron pellets are used to control woody species, it is important to remember that there is a period of years following treatment that it is inadvisable to burn. Therefore special caution should be taken when stocking pastures to ensure that the tallgrass community remains dominant. Other invaders such as sericia lespedeza and eastern redcedar also thrive once released from the oak canopy.

Community 3.2
Midgrass Dominant

This community is dominated by less palatable midgrass species. Abusive grazing has resulted in the decline of palatable tallgrasses and forbs. Little bluestem will persist, along with dropseed species, silver bluestem, native lovegrasses, sideoats grama, and broomsedge bluestem(in eastern portions of MLRA). Annual forbs increase in abundance. Total site production may be similar to community 3.1 but composition has changed significantly.

Pathway 3.1A
Community 3.1 to 3.2

Tallgrass Dominant

Midgrass Dominant

Abusive grazing practices exceeding carrying capacity without adequate rest/recovery can push this tallgrass dominated plant community towards a community that is dominated by less palatable midgrass species.

Pathway 3.2A
Community 3.2 to 3.1

Midgrass Dominant

Tallgrass Dominant

Through a properly implemented prescribed grazing system that includes some degree of growing season rest, this community phase may be reverted to the reference plant community. The length of deferment and time required for this restoration is dependent upon precipitation and management system used.

State 4
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.

Resilience management. This state is not likely to return to reference conditions due to the alteration of soil structure, chemistry and hydrology. However, if abandoned, the site may become invaded by woody species and transition to something similar to the woodland state.

Community 4.1
Cropland/Tame Pasture

With brush management, tillage, seeding and/or sprigging, this site can support a variety of native and non-native plant communities. Good grazing management and, occasionally, reseeding may be needed to re-establish and maintain desired plant communities. Once tillage has occured, physical and biological soil properties have been significantly altered. The return of this state to the reference state may not be achievable. However, range seeding, prescribed fire and proper grazing management can restore a plant community similar the the reference state.

State 5
Eroded

This state is the result of water erosion over bare soil.

Characteristics and indicators. Most of the "A" horizon of the soil profile has been displaced. The remaining subsoil is very low in fertility. Some native grasses and forbs will persist in this state, however, production is greatly reduced.

Resilience management. Site specific evaluations are required on eroded soils in order to determine what restoration options are feasible.

Transition T1A
State 1 to 2

In the absence of fire or brush management, this savannah state will transition to a woodland state of tree/shrub dominance.

Constraints to recovery.Overall woody infestation level and time since fire will determine level of restoration needed.

Transition T1B
State 1 to 3

Through intensive chemical brush management, the savannah state may be transitioned to a grassland state dominated by tallgrasses or midgrasses with very few trees and shrubs. It is important to note that maintaining this state will require significant inputs.

Context dependence.A large number of acres of Sandy Loam Savannah sites have had an attempt at clearing woody species through chemical herbicide use. Mid-century use of 2,4,5-T and other similar chemicals led to large areas of timber kill. However, many of these areas resprouted into thicker and denser "scrub oak" mottes. More recently, tebuthiuron pellets have been used in attempts to open up more grazable acres for cattle production. Some have had success, however, many times the canopy release leads to secondary invasions by eastern redcedar, sericea lespedeza, and broomsedge bluestem. Careful planning and consideration should be used before attempting chemical application in the cross timbers.

Transition T1C
State 1 to 4

Through land clearing tillage and seeding the sandy savannah site may be converted to cropland or tame pasture

Context dependence.Once tillage has occurred, physical and biological soil properties have been significantly altered. The return of this state to the reference state may not be achievable.

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. Fire alone can help restore the site, however, this may take many years to accomplish.

Context dependence.Overall woody encroachment level and time since fire have an impact on restoration efforts.

Transition T2A
State 2 to 3

Through intensive chemical brush management, the woodland state may be transitioned to a grassland state dominated by tallgrasses or midgrasses with very few trees and shrubs. It is important to note that maintaining this state will require significant inputs. A large number of acres of Sandy Loam Savannah sites have had an attempt at clearing woody species through chemical herbicide use. Mid-century use of 2,4,5-T and other similar chemicals led to large areas of timber kill. However, many of these areas resprouted into thicker and denser "scrub oak" mottes. More recently, tebuthiuron pellets have been used in attempts to open up more grazable acres for cattle production. Some have had success, however, many times the canopy release leads to secondary invasions by eastern redcedar, sericea lespedeza, and broomsedge bluestem. Careful planning and consideration should be used before attempting chemical application in the cross timbers.

Transition T2B
State 2 to 4

Through land clearing tillage and seeding the sandy savannah site may be converted to cropland or tame pasture land use.

Constraints to recovery.Once tillage has occurred, physical and biological soil properties have been significantly altered. The return of this state to the reference state may not be achievable.

Restoration pathway R3A
State 3 to 1

This state may be restored to the savannah state with the exclusion of chemical brush management.

Context dependence.A prescribed fire program must be implemented to control resprouting woody species and maintain an open savannah canopy. Otherwise, the site could transition to the woody dominated state. This restoration may take many years.

Transition T3A
State 3 to 2

In the absence of fire or brush management, this grassland state will transition to a woodland state of tree/shrub dominance.

Transition T3B
State 3 to 4

Through tillage and seeding the grassland state may be converted to cropland or tame pasture land use.

Constraints to recovery.Once tillage has occurred, physical and biological soil properties have been significantly altered. The return of this state to the reference state may not be achievable.

Restoration pathway R4A
State 4 to 1

The potential for this converted state to revert to another state varies greatly from site to site. It is dependent upon multiple factors including length of time in production, soil integrity, planned restoration methods, and precipitation patterns. The return of soil properties to reference condition may not be achievable, post cultivation. Introduced pasture species are also very difficult to eradicate once established. Consult with local conservationists to develop a site specific restoration plan.

Transition T4A
State 4 to 5

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