State 1
Reference

The Reference State is dominated by warm-season perennial grasses, a composite of predominantly native species of tallgrasses and midgrasses, interspersed with numerous perennial forbs. A small component of shrubs and cool-season grasses also occur. This state has three plant community phases that are dynamic in nature and are dependent on fire frequency and grazing impacts.

Characteristics and indicators. An introduction and/or increase of woody plants can occur in the Reference State and initiates the transition to the Woody Invaded State. The lengthening of fire return interval, lack of fire intensity, and lack of competition from the warm-season perennial grasses, the greater the chance of woody species to establish and increase. Within the Reference State, the woody vegetation will generally be less than 15 percent canopy cover per acre. An introduction of seed from introduced, invasive or noxious plants can occur in the Reference State and is the starting point for transition to the Pastureland State. If introduced, invasive, or noxious plants are present, they should not exceed those percentages shown in the plant communities identified in the Pastureland State. Tillage has not been a disturbance in the Reference State.

Resilience management. The Reference State is maintained through fire, grazing, and management. Fire will have a return interval of one to three years that includes the timing and intensity to negatively impact undesirable species. Grazing will include a forage-animal balance and adaptive decision-making to ensure the dominant plants within the reference plant community can maintain vigor. Management will include strategies to prevent non-native seed introduction (woody or herbaceous) and scouting with targeted control methods if initial establishment occurs.

Community 1.1
Reference

Figure 9. Reference Plant Community Gravelly Upland

The interpretive plant community for the Gravelly Upland ecological site is the Reference Plant Community and represents the original plant community that existed prior to European settlement. Characterized as open grassland essentially free of trees and large shrubs, it is dominated by tall and mid warm-season grasses including big bluestem, little bluestem, sideoats grama, switchgrass, and Indiangrass. Combined, these grasses will account for 80 percent of vegetation produced annually. Other prevalent grasses are Florida paspalum, purple lovegrass, Canada wildrye, Scribner’s rosette grass, sedges, and Virginia wildrye. The site supports a wide variety of warm-season forb species which are interspersed throughout the grass sward. The forb components make up 10% of the total annual production and include Maximilian sunflower, willowleaf sunflower, wholeleaf rosinweed, compassplant, Nuttall’s sensitive-briar, and prairie bundleflower. Shrubs make up 5% and include leadplant, New Jersey tea, fragrant sumac, and prickly pear.

Resilience management. This is a stable plant community when grazing and fire are adequately managed. A prescribed grazing program that incorporates periods of grazing rest and recovery of key forage species during the growing season benefits the tallgrasses as well as the more palatable forb species. Excessive grazing and livestock trailing can quickly impact soil stability and lead to sheet and gully erosion. Because this site often occurs on summits, shoulders, and other high elevations on the landscape, it is preferred by grazing animals during the hot days of late summer. Cattle and other livestock commonly graze into the prevailing southerly winds and find loafing areas in this site to gain relief from heat and insects. Concentrated livestock use, such as winter-feeding areas, can cause compaction of the wet, clay soils and stress the dominant tallgrasses.

Community 1.2
Midgrass

This community is characterized by a mixture of tallgrasses and midgrasses. Compared to the Reference Plant Community, there has been a reduction in the more palatable tallgrasses and forbs with an increase in midgrasses and other forbs. Tallgrasses such as big bluestem, Indiangrass, and switchgrass still remain, but the proportion of midgrasses such composite dropseed, little bluestem, purpletop tridens, marsh bristlegrass, beaked panicum, broomsedge bluestem, and sideoats grama has increased to 40 to 50 percent of the total annual production. Palatable forbs such as Maximilian sunflower, compassplant, wholeleaf rosinweed, Nuttall’s sensitive-briar, and prairie bundleflower have decreased and largely been replaced by white heath aster, white sagebrush, Cuman ragweed, and Canada goldenrod. Forbs produce 8 to 10 percent of the total annual production. In some locations shrubs such as smooth sumac, roughleaf dogwood, blackberry, and coralberry may be found. A variety of invasive trees species such as Osage-orange, post oak, common hackberry, elm, honeylocust, and eastern red cedar may also be present. Shrubs and trees comprise of 5 to 10 percent of total production.

Resilience management. The Midgrass plant community persists with the use of a forage-animal imbalance as a grazing strategy and a longer fire return interval, approximately 5 to 7 years. The forage-animal imbalance results in excessive grazing (plants experiencing intensive and frequent leaf removal) on preferred species such as big bluestem, Indiangrass, and palatable legumes. Lack of fire allows residual build-up of old growth on less palatable species and a potential increase in woody species that further amplifies animal selection of desirable plants.

Pathway 1.1A
Community 1.1 to 1.2

The mechanisms that transition the Reference Plant Community to a Midgrass Plant Community include repetitive, excessive leaf removal of the key tallgrass forage species in conjunction with longer fire return intervals than historically occurred in the Reference Plant Community. The repetitive, excessive leaf removal is driven by a forage-animal imbalance (no rest or recovery). Drought conditions with below average rainfall during the first half of the growing season will amplify the annual imbalance due to overall reduced forage production and extended (>3 years) drought will accelerate the rate of transition. Having longer fire return intervals and a forage-animal imbalance lasting for periods greater than 10 years will shift functional and structural plant group dominance towards a midgrass plant community. Initial increases in forbs, as tallgrasses are reduced in vigor, could trigger a desire by land managers to utilize herbicides to reduce forb presence. Broadcast application of broadleaf herbicides will remove legumes and forbs and result in a grass dominated community but not improve tallgrass species vigor.

Context dependence. Plant community composition shifts from Tallgrass to Midgrass dominant.

Pathway 1.2A
Community 1.2 to 1.1

The restoration from a Midgrass Plant Community to a Reference Plant Community requires a shift in management (10-15 years) that includes a forage-animal balance allowing sufficient leaf material to remain on the key tallgrass forage species (big bluestem, switchgrass, Indiangrass, and little bluestem) and palatable legumes within the Reference Plant Community. Adaptive decision-making is required to allow adequate rest and recovery for the key plants and meet a forage-animal balance, especially when drought conditions are encountered. If woody species are present, prescription fires every 6-8 years will be necessary for their removal and/or maintenance. Targeted spot treatment of non-native plants (herbaceous and woody) is needed if present.

Context dependence. Short-term (less than 5 years) adjustment in management can improve tallgrass vigor, but functional and structural group dominance change is likely to require 7 to 10 years depending on growing season moisture during that time-frame.

State 2
Woody Invaded

The Woody Invaded State is dominated by a shrub and/or tree plant community. The increase and spread of shrubs and trees resulted from an absence of fire and will be accelerated by seed introduction and/or spread. Woody plants can increase up to 34% from a lack of fire according to a study from 1937 to 1969, in contrast to a 1% increase on burned areas (Bragg and Hulbert, 1976). Periodic burning will hinder the establishment of most woody species and favor forbs and grasses. However, not all unburned areas have a woody plant invasion. Birds, small mammals, and livestock are instrumental in the distribution and spread of seed for most tree and shrub species common to this site. The speed of encroachment varies considerably and can occur on both grazed and non-grazed sites.

Characteristics and indicators. Hydrologic function in the Woody Invaded State is affected by the amount of shrub and/or tree cover compared to the Reference State. Canopy interception loss can vary from 25.4% to 36.7% (Thurow and Hester, 1997). A small rainfall event is usually retained in the foliage and does not reach the litter layer at the base of the tree. Only when canopy storage is reached and exceeded does precipitation fall to the soil surface. Interception losses associated with the accumulation of leaves, twigs, and branches at the bases of trees are considerably higher than losses associated with the canopy. The decomposed material retains approximately 40% of the water that is not retained in the canopy (Thurow and Hester, 1997). Soil properties affected include biological activity, infiltration rates, and soil fertility. The Woody Invaded State has not had tillage as a disturbance and could have plants identified in the Pastureland State present on the site.

Resilience management. The Woody Invaded State is sustained by lack of fire and lack of woody plant control methods such as mechanical, chemical, or biological. Livestock that utilize browse will have greater livestock production potential in this state than those preferring plants in the Reference State. The lack of sunlight, due to shading by the shrubs and/or trees, will favor cool-season grasses that can reduce fire intensity if fire timing is during their active growth period and would help sustain the Woody Invaded State.

Community 2.1
Shrub and/or Tree

The Shrub and/or Tree Plant Community is dominated by trees and shrubs and may account for 40 to 60 percent total vegetation. Primary trees include post oak and eastern red cedar. Trees such as osage orange and honeylocust are common invaders that become established in some areas. Abundant shrubs are coralberry, roughleaf dogwood, blackberry, and smooth sumac. Coralberry is generally the most abundant shrub and often forms low, dense thickets throughout the site. The spread of shrubs and trees results from the absence of fire because periodic burning tends to hinder the establishment of most these woody species and favors grasses and forbs. It should be noted, however, that not all unburned areas have a woody plant problem and that the rate of encroachment varies considerably depending on seed availability in surrounding areas. Longtime overgrazing can also lead to encroachment. In these situations, the associated grasses will usually consist of composite dropseed, purple lovegrass, Kentucky bluegrass, fescue, and Scribner’s rosette grass. Shrubs and trees will also invade areas where both grazing and fire have been excluded for many years because the heavy accumulation of plant mulch and litter retards herbage growth and provides a favorable habitat for seed germination and establishment of many shrub species. The associated grasses in this situation may include big bluestem, little bluestem, Indiangrass, switchgrass, sedges, and Canada wildrye. Grass production is significantly reduced by competition from forbs and woody species. Grass yields vary from 30 to 40 percent of the total vegetative production while forbs often produce 10 to 50 percent of the total. Major forbs include white sagebrush, Cuman ragweed, Baldwin ironweed, and common yarrow.

Resilience management. The Shrub and/or Tree Community is sustained by lack of fire and lack of woody plant control methods such as mechanical, chemical, or biological. A prescribed burning program accompanied by prescribed grazing will gradually return the plant community to one dominated by desirable grasses and Forbs. Special planning will be necessary to assure that sufficient amounts of fine fuel are available to carry fires with enough intensity to control woody species. Use of labeled herbicides as a brush management tool will usually be necessary to reduce populations of fire-resistant species like Osage orange and honeylocust and accelerate the recovery of desired vegetative cover.

State 3
Prior-Tilled

The Prior-Tilled State consists of abandoned cropland where the original plant community was destroyed through inversion by tillage but revegetation has occurred. Two plant communities are identified in the Prior-Tilled State and are identified by revegetation factors. The communities are identified as being naturally revegetated through succession (Go-back) or planted/seeded to species similar in composition to the reference plant community (Reseed). Plant species composition in the Prior-Tilled State is difficult to define due to the variability of plant communities that can exist.

Characteristics and indicators. The Prior-Tilled State is an alternative state since the energy, hydrologic, and nutrient cycles are significantly altered to that of the Reference State in its natural disturbance regime. Repeated tillage and planting of annual crops resulted in major changes in soil conditions. Reductions in organic matter, mineral levels, soil structure, oxygen levels, and water holding capacity, along with increased runoff/erosion and shifts in the populations of soil-dwelling organisms, are common in this state. The extent of these changes are dependent upon duration of cropping, crop types grown, and other management practices. Bulk density, aggregate stability, soil structure, and plant functional and structural groups are not fully restored to that of the Reference State. Mechanical tillage can destroy soil aggregation. Soil aggregates are an example of dynamic soil property change. Aggregate stability is critical for infiltration, root growth, and resistance to water and wind erosion (Brady and Weil, 2008).

Resilience management. The Prior-Tilled State is a result of a land use management decision and is sustained by diminished soil function. Implementation of practices that positively impact plant community diversity, energy flow, and nutrient and water cycle, should benefit rehabilitation. Documentation does not support rehabilitation to a Reference State within known management time frames.

Community 3.1
Go-Back

This plant community also occurs on areas that were formerly farmed. When tillage operations ceased, the areas were allowed to revegetate or “go back” naturally in contrast to artificial reseeding to a selected species or group of species. The go-back process is a slow, gradual transformation that requires many years and many successional changes or stages in the plant community. The speed and extent of revegetation depends on the size of the area, level of grazing management and the proximity of the area to existing seed sources. In the initial stages of revegetation the site is usually dominated by annual forbs such as annual ragweed, slender snakecotton, Canadian horseweed, prairie sunflower, common sunflower, Mexican fireweed, camphorweed, and annual buckwheat. Gradually these are replaced by annual grasses including prairie threeawn, mat sandburbuffalo bur, tumblegrass yellow foxtail, little barley, cheatgrass, and witchgrass. As plant succession progresses the plant community gradually becomes dominated by perennials. The major grasses includes and dropseed, composite dropseed, thin paspalum, purple lovegrass, red lovegrass, Scribner’s rosette grass, Carolina crabgrass, silver beardgrass, and tumble windmillgrass. Common forbs are Cuman ragweed, white sagebrush, Carruth’s sagewort, white heath aster, Missouri Canada goldenrod, and sand Green antelopehorn milkweed. Combinations of these plants can form a stable community. In time with prescribed grazing management, other perennial grasses and forbs common in the Reference Plant Community return to the site. Blue grama is a shortgrass that is very common to the native plant communities on this site. However, it seldom occurs in go-back communities, even after 40 to 50 years of plant succession. Some go-back areas are invaded by trees and shrubs. The more common include elm, common hackberry, eastern redcedar, eastern cottonwood, and roughleaf dogwood. Occasional burning is effective in controlling these woody plants. Total annual production varies by site. This depends on seasonal precipitation and the stage of plant succession in the plant community.

Resilience management. Following termination of cultivation, total annual production is quite variable and full recovery of the original plant community, including forbs and legumes, may take many decades. Additions of organic matter and minerals, deferred grazing, prescribed burning, and related management practices described earlier for this ecological site can be beneficial to the rehabilitation.

Community 3.2
Reseed

This plant community occurs on areas that were formerly farmed and reseeded with a mixture of native species common in the Tallgrass Plant Community. Most seeding mixtures consisted of a blend of grasses that include sand big bluestem, Indiangrass, switchgrass, little bluestem, sideoats grama, blue grama, and western wheatgrassEastern gamagrass. In some locations, seed of legumes and forbs such as prairie bundleflower and Maximilian sunflower were included in the mixture. Once these areas become fully established, and the natural historical disturbances such as grazing and burning are included in management, production is comparable to that of the Tallgrass Plant Community. Total annual production ranges varies according to the species planted, established plants, and years of establishment. When reseeded areas and areas supporting native rangeland exist in the same pasture, they seldom are utilized at the same intensity because domestic livestock usually prefer plants growing on the native rangeland areas. When feasible, reseeded plant communities should be managed as separate pastures or units. Some seeded areas are invaded by trees and shrubs during the establishment period of the desired plants. These invader species commonly include elm, common hackberry, eastern redcedar, and eastern cottonwood. Occasional burning is effective in controlling establishment of these woody plants.

Resilience management. Following termination of cultivation, total annual production is quite variable and full recovery of the original plant community, including forbs and legumes, may take many decades. Additions of organic matter and minerals, deferred grazing, prescribed burning, and related management practices described earlier for this ecological site can be beneficial to the rehabilitation.

State 4
Invasive Herbaceous

The Invasive Herbaceous State is identified by a significant presence of non-native herbaceous plant species and is characterized by the composition of plant species and soil functions that govern the ecological processes.

Characteristics and indicators. Species that define this state include sericea lespedeza and Caucasian bluestem. Sericea lespedeza and Caucasian bluestem community phases are partially defined by the total production exceeding 15% by weight on a per acre basis. Ecological processes within this state that are affected and differ from the Reference State are hydrologic cycle and nutrient cycle. Water content and infiltration rates are also affected by the species in the plant community phase.

Resilience management. The Invasive Herbaceous State is sustained through continued reduction in health and vigor of native plant species and the increase in health and vigor, including seed production, of non-native herbaceous species. Ensuring a lack of forage quality due to season of grazing, and type of grazing animal, of the non-native plants will deter grazing of non-native plant species and increase grazing pressure on native plant species. A general lack of treatment measures for individual species control, maintenance, and/or eradication will also allow persistence of this state.

Community 4.1
Caucasian Bluestem

Caucasian bluestem is present at levels exceeding 15% by weight on a per acre basis and governing the ecological processes and potential uses of this community. Caucasian bluestem might be the most serious threat and most aggressive of the introduced, invasive, and noxious species of this time. Interspatial erosion can be present due to the clumpy growth of the plant which leads to a rough surface to walk or drive on. Caucasian bluestem is allelopathic (producing toxic chemicals that negatively impact the germination and/or growth of other plants) and often exists as a monoculture due to its competitive ability. Having this species present on a site can and will allow further invasion of adjacent sites if proactive prevention and control measures are not implemented. Research and trial studies are continuously being conducted on control measures for Caucasian bluestem. Soil dynamic property changes include infiltration, biological activity, and soil fertility.

Resilience management. Caucasian bluestem is extremely competitive with its allelopathic nature, lower palatability compared to native species, ability to persist with heavy utilization, and tolerance to drought. To prevent further loss of native plant composition, ensure native plant vigor remains high via a forage-animal balance based on forage composition and palatability, and utilize spot application of herbicides to control new and existing Caucasian bluestem plants. Fire can be utilized to remove standing dead growth and increase palatability of Caucasian bluestem in a mixed plant community, especially initial spring growth. Impacts to Caucasian bluestem via alternate timing of fire (late summer) is currently being investigated. There have been cases where the native taller grasses appear to shade and out-compete the Caucasian bluestem, but more commonly, it is crowding out the native grass as it spreads. There are ungrazed places on the Konza Prairie Research and biological station where Caucasian bluestem was introduced from feeding livestock contaminated hay and it is now crowding out the native grass.

Community 4.2
Sericea Lespedeza

Sericea lespedeza (Lespedeza cuneata) is present at levels exceeding 15% by weight on a per acre basis and governing the ecological processes and potential uses of this community. Sericea lespedeza is invasive and listed as a statewide noxious weed in Kansas. It competes with the native plant community for sunlight, water, and nutrients, and produces allelopathic compounds (toxic chemicals that negatively impact the germination and/or growth of other plants). It also contains tannins, that limit palatability, and produces copious amounts of seed that remain viable in the soil for decades. This species will quickly invade rangelands without proactive control measures.

Resilience management. Sericea lespedeza (Lespedeza cuneata) is extremely competitive with its allelopathic nature, lower palatability compared to native species, and good seedling vigor. To prevent further loss of native plant composition, ensure native plant vigor remains high via a forage-animal balance based on forage composition and palatability, utilize spot application of herbicides to control new and existing sericea lespedeza plants, and consider diversifying grazing livestock type. Control measures for sericea lespedeza involve herbicide application following extension recommendations and product label for proper rates and timing. Utilization and control can also be provided through sheep and goat grazing. Conventional management practices such as prescribed grazing with cattle and dormant-season fire have been less than effective in preventing the spread of sericea lespedeza in rangelands. Some suppression of sericea lespedeza has been observed after mowing or summer burning. Late summer fire significantly reduces seed production the year of burn. An integrated approach is needed when treating this species.

State 5
Cropland

This State is dominated by row crops such as corn, soybeans, and wheat. It occurs on sites that have been mechanically tilled and converted to agricultural cropland. After tillage, efforts are then taken to plant various crops through a conservation cropping system.

Community 5.1
Cropland Plant Community

This community occurs on areas where land use has been converted to intensive agriculture cropland through mechanical tillage and a conservation cropping system. Primary crops include corn, soybeans, and wheat.

State 6
Pastureland

The Pastureland State is identified by a significant presence of non-native herbaceous plant species and is characterized by the composition of plant species, agronomic inputs from direct fertilization, and soil functions that govern the ecological processes. Sites consisting of introduced species and managed for their continued presence or spread should not be evaluated within this model and instead, consider using a separate land use model such as Pasture.

Characteristics and indicators. Tall fescue, smooth brome, and Kentucky bluegrass are partially defined by the total production exceeding 40% by weight on a per acre basis. Ecological processes within this state that are affected and differ from the Reference State are hydrologic cycle and nutrient cycle. Water content and infiltration rates are also affected by the species in the plant community phase.

Resilience management. Pastureland is sustained through continued reduction in health and vigor of native plant species and the increase in health and vigor, including seed production, of non-native herbaceous species. Agronomic inputs from direct fertilization or nutrient-rich runoff from adjacent crop fields will provide advantages for non-native cool-season grass species growth. Ensuring a lack of forage quality due to season of grazing, type of grazing animal, or chemical composition of the non-native plants will deter grazing of non-native plant species and increase grazing pressure on native plant species. A general lack of treatment measures for individual species control, maintenance, and/or eradication will also allow persistence of this state.

Community 6.1
Fescue, Brome, Bluegrass

Tall fescue, smooth brome, and Kentucky bluegrass (all being cool-season grasses) are present at levels exceeding 40% by weight on a per acre basis and are governing the ecological processes and potential uses of this community. Timing of plant growth has shifted from summer (May through August) and now mostly occurs in spring and fall (March to May and September to November). Fire intensity of late spring burns can be greatly impeded due to the significant quantity of cool-season grass present. Any one or a combination of these species can be considered an invaded community. Soil dynamic property changes include biological activity and soil fertility.

Resilience management. Tall fescue, smooth brome, and Kentucky bluegrass are sustained or increased with nutrient additions and absence of fire. To prevent further loss of native plant composition, avoid nutrient additions, ensure native plant vigor remains high via a forage-animal balance based on forage composition and seasonal availability, utilize herbicides when natives are dormant but cool-seasons are actively growing, and utilize consecutive late spring prescribed burns. Chemical control will involve herbicide application following extension recommendations and product label for proper rates and timing. Intensifying grazing pressure (leaf removal of cool-season grasses) during the spring and fall and removing grazing pressure during the summer will reduce cool-season grass vigor and allow native warm-season plants an opportunity to maximize growth and gain vigor. Prescribed burning will require sufficient standing dead material in order to conduct a burn in late spring as warm-season grasses initiate growth. If the goal is continued presence or spread of tall fescue, smooth brome, or Kentucky bluegrass, consider using a separate land use model such as Pasture.

Transition T1A
State 1 to 2

Long term fire suppression (20+ years) will transition the Reference State to a Woody State. A lack of fire events will allow woody species to establish and increase, shifting the site to dominant trees and shrubs with a reduction in desirable grasses and forbs in the understory.

Transition T1B
State 1 to 4

A transition from Reference to an Invasive Herbaceous State occurs when the site is invaded by either Caucasian bluestem and/or Sericea lespedeza with the total production exceeding 15% by weight on a per acre basis.

Transition T1C
State 1 to 5

Tillage (or no-till if that management style is preferred) and seeding of agricultural crops will transition this site from a Reference State to a Cropland State.

Restoration pathway R2A
State 2 to 1

Restoration actions to return to a Reference State may include machinery woody removal and prescribed fire. Efforts will be costly, labor-intensive, and can take many years, if not decades. Once canopy levels reach greater than 20 percent, estimated cost to remove trees is very expensive and includes high energy inputs.

Transition T2A
State 2 to 5

Tillage (or no-till if that management style is preferred) and seeding of agricultural crops will transition this site from a Woody State to a Cropland State.

Transition T4A
State 4 to 5

Tillage (or no-till if that management style is preferred) and seeding of agricultural crops will transition this site from an Invasive Herbaceous State to a Cropland State.

Transition T5A
State 5 to 3

Allowing the site to naturally revegetate as it regenerates, or reseeding the site with native grasses and forbs with proper management afterwards will transition this site from a Cropland to a Prior-Tilled State.

Transition T5B
State 5 to 6

Seeding of cool season grasses and forbs and proper pasture management will transition this Cropland to a Pastureland.

Transition T6A
State 6 to 4

A transition from Pastureland to an Invasive Herbaceous State occurs when the site is invaded by either Caucasian bluestem and/or Sericea lespedeza with the total production exceeding 15% by weight on a per acre basis.

Transition T6B
State 6 to 5

Tillage (or no-till if that management style is preferred) and seeding of agricultural crops will transition this site from a Pastureland to a Cropland.