State 1
Grassland State

The Grassland State defines the ecological potential and natural range of variability resulting from the natural disturbance regime of the Limy Hills ecological site. This state is supported by empirical data, historical data, local expertise, and photographs. It is defined by a suite of native plant communities that are a result of periodic fire, drought, and grazing by bison. These events are part of the natural disturbance regime and climatic process. The soil dynamic properties that can influence community phase and state changes are organic matter content, biological activity, aggregate stability, infiltration, soil fertility, and soil reaction. Other grazing and feeding animals such as elk, pronghorns, deer, rabbits, insects, and numerous burrowing rodents had secondary influences on plant community development. Today, cattle are the primary grazers on this ecological site. Within the grassland state, the woody vegetation will generally be less than 15 percent canopy cover per acre. If introduced, invasive or noxious plants are present, they should not exceed 15 percent of the total pounds of vegetation produced per acre in order to avoid crossing a threshold. Plant communities within this state function similarly in their capacity to limit soil loss, cycle water, and produce vegetative biomass. The plant community phases can vary through changes in grazing management or fluctuating climatic conditions. The variables that control the resilience of this grassland state are long-term grazing management and frequency of fire.

Characteristics and indicators. Tallgrasses and Migrasses are dominant in the Grassland State.

Resilience management. Management strategies that will sustain this state include monitoring key forage species and providing a forage and animal balance.

Community 1.1
Reference Plant Community

Figure 11. MLRA 76 Limy Hills Reference Plant Community.

The interpretive plant community for the Limy Hills ecological site is the Reference Plant Community, and represents the original plant community that existed prior to European settlement. The site is characterized as a grassland with a minor scattering of shrubs. It is dominated by tall-, warm-season grasses including big bluestem, switchgrass, and Indiangrass. The major midgrass species is little bluestem. Combined, these grasses will account for 70 to 80 percent of vegetation produced annually. Other prevalent grasses are sideoats grama, western wheatgrass, and blue grama. Scattered throughout are minor amounts of numerous mid- and shortgrasses. The site supports a wide variety of legume species which are interspersed throughout the grass sward. The most abundant are slimflower scurfpea, Nuttall’s sensitive-briar, Maxmilian sunflower, prairie bundleflower, and blue wild indigo. Other important forbs include compassplant, wholeleaf rosinweed, dotted blazing star, pitcher sage, upright prairie coneflower, and Cuman ragweed. Leadplant and Jersey tea are low growing shrubs that occur over the site. Unlike most shrubs, these plants are both quite tolerant to fire. Occasional clumps of coralberry and fragrant sumac may be found on the steeper sloped exposures or in areas of rock outcrops.

Resilience management. This is a stable plant community when grazing and fire are adequately managed. A prescribed grazing program that incorporates periods of rest and recovery during the growing season benefits the tallgrasses and even 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 shoulders and backslopes and other high elevations on the landscape, it is preferred by grazing animals during the hot days of late summer to gain relief from heat and insects. Concentrated livestock use, such as winter feeding areas, can cause compaction and stress the dominant tallgrasses.

Community 1.2
Midgrass/Tallgrass Community

Figure 14. MLRA 76 Midgrass/Tallgrass Plant Community.

The composition of this plant community is dominated by midgrasses and tallgrasses but is lacking in prominence of many of the productive, highly preferred forbs found in the Reference Plant Community. Additionally, eastern gamagrass is significantly reduced where it occurs on the site. This plant community developed as a result of years of overgrazing. Although tallgrasses (big bluestem, Indiangrass, and switchgrass) only make up 20 to 30 percent of total production, they tend to dominate the visual aspect of the site. Midgrasses are the primary producers of the site and make up 40 to 50 percent of the production. Dominant midgrasses include little bluestem, sideoats grama, western wheatgrass, and composite dropseed. Shortgrasses such as blue grama, hairy grama, buffalograss, tumble windmill grass, and prairie threeawn produce 5 to 10 percent of the vegetation. Forb production is variable and may range from 10 to 20 percent of the total vegetation depending on amounts and timing of rainfall events. Perennial forbs include white sagebrush, slimflower scurfpea, Missouri goldenrod, blue wild indigo, white heath aster, and Cuman ragweed. In some locations shrubs and trees such as fragrant sumac, eastern redcedar, and coralberry comprise up to 10 percent of the composition.

Resilience management. This community generally occurs as a result of long-term, heavy continuous grazing. The appearance of the site is that of the Reference Plant Community with some of its preferred forbs significantly reduced. It normally has a slightly higher percentage of grasses than the Reference Plant Community and the increasing forbs are generally not as noticeable as were those which decreased. This community is quite common on ranches which are very conscious of proper stocking but may not have a grazing system or grazing rest and recovery program to enhance the site’s more fragile species. The plant community is relatively stable with moderate grazing when not adversely affected by drought or other major stress factors. With continuous overgrazing it may deteriorate to a midgrass-shortgrass community over a period of several years. Prescribed grazing with adequate rest and recovery periods during the growing season will shift this plant community to include more productive tallgrasses. Continuation of such management can shift the plant community to near the Reference Plant Community in a few years.

Community 1.3
Midgrass/Shortgrass Community

This plant community developed as a result of long-term, heavy, continuous overgrazing. Midgrasses dominate the site and comprise 40 to 55 percent of the annual production. Most abundant midgrasses include little bluestem, sideoats grama, western wheatgrass, and composite dropseed. Shortgrasses such as blue grama, hairy grama, buffalograss, tumble windmill grass, and annual threeawn produce 20 to 30 percent of the vegetation. Remnant plants of big bluestem, Indiangrass, and switchgrass are commonly found only in protected locations. These plants are usually grazed repeatedly and remain in a low state of vigor. Of these remnants, big bluestem is generally the most abundant because it has rhizomes that can persist for many years in a weakened condition. When in this state, new growth consisting of three to five leaves will emerge in a prostrate rather than upright position, allowing plants to partially escape grazing. These remnants respond favorably to periods of rest from grazing and may regain vigor in two to three years. However, their numbers or the percentage of composition is so reduced it may take many years to regain a large role in the species composition. Forb production is quite variable and may range from 15 to 25 percent of the total vegetation depending on amounts and timing of rainfall events. Perennial forbs include white sagebrush, slimflower scurfpea, Missouri goldenrod, blue wild indigo, white heath aster, and Cuman ragweed. In some locations shrubs and trees such as fragrant sumac, roughleaf dogwood, eastern redcedar, and coralberry comprise up to 15 percent of the vegetation.

Resilience management. Remnant plants of big bluestem, Indiangrass, and switchgrass are commonly found only in protected locations. These plants are usually grazed repeatedly and remain in a low state of vigor. Of these remnants, big bluestem is generally the most abundant. It has rhizomes that can persist for many years in a weakened condition. When in this state of vigor, new growth consisting of three to five leaves will emerge in a prostate position rather than upright. This allows the plants to partially escape grazing. These remnant plants respond favorably to periods of rest from grazing and may regain vigor in two to three years. However, their numbers or percentage of composition is greatly reduced that it may take many years to regain a large role in the plant community. Prescribed grazing with adequate rest and recovery periods during the growing season will shift this plant community to include more productive tallgrasses. With continued management the taller grasses will gradually increase in vigor and abundance to dominate the landscape.

Pathway 1.1 to 1.2
Community 1.1 to 1.2

Reference Plant Community

Midgrass/Tallgrass Community

These mechanisms include management controlled by repetitive heavy use, no rest or recovery of the key forage species and no forage and animal balance for many extended grazing seasons. This type of management lasting for periods greater than 10 years will shift functional and structural plant group dominance towards a midgrass plant community. Annual burning or a fire frequency occurrence <2 years will cause a shift in community phases. The frequency of late spring annual burning in combination with late season rest may result in a shift in species diversity as well as fluctuations in productivity. Herbicide use every 1-3 years will remove legumes and forbs and become a grass dominated community. Drought conditions that persist >3 years with below average rainfall during the first half of the growing season in addition to inadequate rest provided for plant recovery will result in productivity changes.

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

Pathway 1.2 to 1.1
Community 1.2 to 1.1

Midgrass/Tallgrass Community

Reference Plant Community

Causes of plant community shift include management (10-15 years) with adequate rest and recovery of the key forage species (big bluestem, switchgrass, Indiangrass, and little bluestem) within the Reference Plant Community . If woody species are present, prescription fires every 6-8 years will be necessary for their removal and/or maintenance.

Pathway 1.2 to 1.3
Community 1.2 to 1.3

These mechanisms include management controlled by repetitive heavy use, no rest or recovery of the key forage species and no forage and animal balance for many extended grazing seasons. This type of management lasting for periods greater than 20 years will shift functional and structural plant group dominance towards a Midgrass/Shortgrass Plant Community.

Pathway 1.3 to 1.2
Community 1.3 to 1.2

Causes of plant community shift include management (10-15 years) with adequate rest and recovery of the key forage species (little bluestem, sideoats grama, big bluestem, switchgrass, and Indiangrass) within the Midgrass/Tallgrass Plant Community . If woody species are present, prescription fires every 6-8 years will be necessary for their removal and/or maintenance.

State 2
Shortgrass State

With heavy, continuous grazing, blue grama and buffalograss will become the dominant species and have a sod-bound appearance. Unable to withstand the grazing pressure, only a remnant population of western wheatgrass remains.

Characteristics and indicators. The Shortgrass State is characterized with specific dynamic soil property changes. Changes between the Grassland State and the Shortgrass State has been documented. As plant community cover decreases from bunchgrasses to more of the sod grasses there is a decrease in infiltration and interception and an increase in surface runoff (Thurow T., 2003).

Resilience management. This is a resistant and resilient state. Grazing management practice should include a forage and animal balance.

Community 2.1
Shortgrass Plant Community

This plant community presents a distinctive shortgrass aspect on the landscape. It is dominated by blue grama and buffalograss with notable amounts of western wheatgrass and sideoats grama present. Other grasses include annual bromes, composite dropseed, Kentucky bluegrass, prairie threeawn, and tumble windmill grass. These species commonly account for 60 to 70 percent of the annual forage production. Like the desirable grasses, palatable legumes and other forbs have been reduced by continuous grazing and competition over many years. Prevalent broadleaf species in this situation include prairie broomweed, annual ragweed, white sagebrush, Cuman ragweed, interior ironweed, wavyleaf thistle, and curlycup gumweed. Forbs may comprise 15 to 25 percent of the total vegetation. This plant community often contains 15 to 20 percent woody species as a result of fewer fires and more opportunities for their encroachment. Eastern redcedar, smooth and/or fragrant sumac, roughleaf dogwood, and coralberry are representative trees and shrubs which occur on this site. Leadplant and Jersey tea may still be found, but are generally much reduced from their prominence in the Reference Plant Community.

Resilience management. This plant community can be managed as a stable shortgrass plant community. If recovery of the tallgrasses, midgrasses, and associated forbs characteristic of the Reference Plant Community is desired, however, many years of careful management that includes prescribed grazing and extended periods of rest during the growing season will be required. More study is necessary in order to document restoration processes to the Grassland State. This site may recover faster than adjoining ones as remnant plants may be somewhat protected by the steeper slopes and occasional surface rocks. Where remnant stands of the desired species are not available on or near the site, reseeding may be necessary to advance recovery. However, seeding or interseeding may be severely limited by the steepness of slope and occasional surface rocks.

State 3
Woody State

This state is dominated by a shrub and/or tree plant community. The increase and spread of shrubs and trees results from an absence of fire. 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, it should be pointed out that not all unburned areas have a woody plant invasion. Birds, small mammals, and livestock are instrumental in the distribution of seed and accelerating the spread of most trees and shrubs common to this site. The speed of encroachment varies considerably and can occur on both grazed and non-grazed pastures. Many species of wildlife, especially bobwhite quail, turkey, and white-tailed deer benefit from the growth of trees and shrubs for both food and cover. When management for specific wildlife populations is desirable, these options should be considered in any brush management plan.

Characteristics and indicators. Hydrologic function is affected by the amount of vegetative cover. 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.

Resilience management. 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. In some locations the use of chemicals as a brush management tool may be desirable to initiate and accelerate this transition.

Community 3.1
Shrub and/or Tree Community

This plant community is dominated by shrubs consisting primarily of coralberry, fragrant sumac, roughleaf dogwood, and smooth sumac which often form low, dense thickets throughout the site. Trees including eastern redcedar, honeylocust, and osage orange have invaded and become established in some areas. Shrubs and trees may produce 40 to 60 percent of the total vegetation. The spread of shrubs and trees results from the absence of fire. Periodic burning tends to hinder the establishment of most of these woody species and favor grasses and forbs. However, not all unburned areas have a woody plant problem. The speed of woody encroachment varies considerably depending on seed availability in surrounding areas. Birds are instrumental in distributing seed and accelerating the spread of shrubs and trees. Woody encroachment may also occur on areas subjected to longtime continuous overgrazing. In these situations the associated grasses will usually consist of composite dropseed, purple lovegrass, plains lovegrass, Kentucky bluegrass, hairy grama, and Scribner’s rosette grass. Shrubs also will invade and spread on areas where both grazing and fire have been excluded for many years. Heavy accumulation of plant mulch and litter retards herbage growth and provides a favorable habitat for seed germination and establishment of many woody species. The associated grasses in this situation are usually 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 40 to 50 percent of the total vegetative production while forbs often produce 15 to 20 percent of the total production. Major forbs include white sagebrush, annual ragweed, Cuman ragweed, prairie broomweed, blue wild indigo, and common yarrow. Forage production on this site is heavily dependent on the predominant woody species (e.g., dense stands of eastern redcedar may have little understory vegetation). Many species of wildlife, especially bobwhite quail and white-tailed deer, benefit from the growth of shrubs for both food and cover. Their needs should be considered in any brush management plan.

Resilience management. Usually a prescribed burning program accompanied with prescribed grazing will gradually return the plant community to one dominated by grasses and forbs. Longer times will be needed where the tall- and midgrasses have been greatly reduced or eliminated. Special planning is 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 recovery of desired vegetative cover.

State 4
Tillage State

Extensive areas of the historic Limy Hills plant communities were plowed and converted to production of cultivated crops by the early European settlers and subsequent generations. In addition to destroying the original plant community, repeated tillage commonly 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, were common on these sites. The extent of these changes depended upon duration of cropping as well as crops grown and other management practices. The Tillage State consists of abandoned cropland that has been naturally revegetated (go-back) or planted/seeded to grassland. Many reseeded plant communities were planted with a local seeding mix under the Conservation Reserve Program (CRP) or were planted to a monoculture of sideoats grama. Go-back communities are difficult to define due to the variability of plant communities that can exist. Many of these communities are represented by the genus Aristida (threeawns).

Characteristics and indicators. This is an alternative state since the energy, hydrologic, and nutrient cycles are altered to that of the Reference State in its natural disturbance regime. 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. This state is a result of a land use management decision.

Community 4.1
Reseed Plant Community

This plant community occurs on areas that were formerly farmed and reseeded with a mixture of native species common in the Reference Plant Community. Most seeding mixtures consisted of a blend of grasses that include sand bluestem, Indiangrass,switchgrass, little bluestem, sideoats grama, blue grama, and western wheatgrass. 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, production is comparable to that of the Reference 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.

Community 4.2
Go-back Plant Community

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 sandbur, tumblegrass, little barley, cheatgrass, and witchgrass. As plant succession progresses the plant community gradually becomes dominated by perennials. The major grasses include sand 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 goldenrod, and sand 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.

State 5
Introduced, Invasive, Noxious State

This state includes three community phases which are characterized by the composition of plant species and soil functions that govern the ecological processes. These three plant communities occur and function independent of one another. Species that define this state include sericea lespedeza, caucasian bluestem, tall fescue, smooth brome, and Kentucky bluegrass. These species can and will invade rangelands without proactive control measures. sericea lespedeza and caucasian bluestem community phases are partially defined by the total production exceeding 15% by weight on a per acre basis. Tall fescue, smooth brome, and Kentucky bluegrass are partially defined by the total production exceeding 40% by weight on a per acre basis.

Characteristics and indicators. Ecological processes within this state that are affected and differ from the grassland state are hydrologic cycle and nutrient cycle. Water content and infiltration rates are affected by the species.

Resilience management. The plant communities that make up this state are sustained by fertilizing species and managing as pastureland or by a lack of treatment measures for individual species control, maintenance, and/or eradication.

Community 5.1
Caucasian Bluestem Community

Caucasian bluestem is the dominant species that govern the ecological processes and uses of this community. This species can and will invade rangelands without proactive control measures.

Resilience management. Caucasian bluestem survives all control measures. There is no way of killing the Caucasian bluestem without killing the native rangeland. There have been cases where the native taller grasses appear to shade and out compete the Caucasian bluestem but there are ungrazed places on the Konza Prairie Research and biological station where it was introduced from feeding livestock contaminated hay and where it now is crowding out the native grass as its spreads. Caucasian bluestem might be the most serious threat and most aggressive of the introduced, invasive, and noxious species of this time. Soil dynamic property changes include infiltration, biological activity, and soil fertility.

Community 5.2
Sericea Lespedeza Community

Sericea lespedeza (Lespedeza cuneata) is the dominant species that govern the ecological processes and uses of this community. Sericea lespedeza is invasive and a statewide noxious weed in Kansas. This species will quickly invade rangelands without proactive control measures. It competes with the native grass community with sunlight, water, and nutrients. It also produces allelopathic compounds (toxic chemicals that negatively impact the germination and/or growth of other plants).

Resilience management. Control measures for sericea lespedeza involve herbicide application. Follow recommended rates and chemical use according to Kansas State University Chemical Weed Control book. Conventional management practices such as prescribed grazing and 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 burning followed by intensive early stocking with stocker cattle. Goats will provide some control as they do eat it much more readily than cattle.

Community 5.3
Fescue, Brome, Bluegrass Community

Tall fescue, smooth brome, and Kentucky bluegrass are the dominant species that govern the ecological processes and uses of this community. Any one or combination of these species can be considered an invaded community at levels of >40% by total weight annual production. Once these levels are reached management choices can change to favor these grasses and as a result land use is transitioned from rangeland to pastureland.

Resilience management. Inputs and energy in order to return species to a grassland state are greater than what is considered to be natural. Control measures for tall fescue, smooth brome, and Kentucky bluegrass might involve herbicide application and/or consecutive prescribed burns. Follow recommended rates and chemical use according to State extension guidelines such as Kansas State University Chemical Weed Control publication. Soil dynamic property changes include biological activity and soil fertility.

Transition 1 to 2
State 1 to 2

Long-term management (approximately 30 years) without a forage and animal balance and heavy, continuous grazing without adequate recovery periods between grazing events will convert the Grassland State to a Shortgrass State made up of blue grama and buffalograss sod. Drought in combination with this type of management will quicken the rate at which this transition occurs.

Constraints to recovery. The ecological processes affected are the hydrologic and nutrient cycles. There is an increase in evaporation rate, runoff, and in bulk density. There is a decrease in infiltration, a change in plant composition, and the functional and structural groups have changed dominance. These are all examples of the soil and vegetation properties that have compromised the resilience of the Grassland State and therefore transitioned to a Shortgrass State.

Transition 1 to 3
State 1 to 3

Changes from a Grassland State to a Woody State lead to changes in hydrologic function, forage production, dominant functional and structural groups, and wildlife habitat. Understory plants may be negatively affected by trees and shrubs by reductions in light, soil moisture, and soil nutrients. Increases in tree and shrub density and size have the effects of reducing understory plant cover and productivity, and desirable forage grasses often are most severely reduced (Eddleman, 1983). As vegetation cover changes from grasses to trees, a greater proportion of precipitation is lost throughout interception and evaporation; therefore, less precipitation is available for producing herbaceous forage or for deep drainage or runoff (Thurow and Hester, 1997).

Constraints to recovery. Recovery is possible through management.

Transition 1 to 4
State 1 to 4

This transition is triggered by a management action as opposed to a natural event. Tillage, or breaking the ground with machinery for crop production, will move the Grassland State to a Tillage State.

Constraints to recovery. The resilience of the Reference State has been compromised by the fracturing and blending of the native virgin sod. The energy, hydrologic, and nutrient cycles are altered and vary from that of the Grassland State.

Transition 1 to 5
State 1 to 5

Changes from a Grassland State to an introduced, invasive and/or noxious state can lead to changes in hydrology/erosion, forage production, wildlife habitat, and soil dynamic properties. These changes will vary depending on dominance of species. This transition is usually triggered by an introduction of non-native species. The source from which the species originated from (i.e. adjacent crop field) can usually but not always be detected. A threshold is crossed once the species (sericea lespedeza and Caucasian bluestem) is established and increases to levels of greater than 15% total annual production per acre. For cool season grasses such as tall fescue and smooth brome that level is >40% total annual production per acre. Changes in species diversity reflect changes in soil biota activity. The introduced, invasive and noxious species are not selected and grazed and as a result become increasingly dominant. Hydrology changes begin to occur with the buildup of litter and interception rates increase as canopy increases.

Constraints to recovery. Need more documentation for recovery processes.

Restoration pathway 3 to 1
State 3 to 1

Restoration efforts will be costly, labor-intensive, and can take many years, if not decades, to return to a Grassland State. Once canopy levels reach greater than 20 percent, estimated cost to remove trees is very expensive and includes high energy inputs. The technologies needed in order to go from an invaded Woody State to a Grassland State include but are not limited to: prescribed burning— the use of fire as a tool to achieve a management objective on a predetermined area under conditions where the intensity and extent of the fire are controlled; brush management—manipulating woody plant cover to obtain desired quantities and types of woody cover and/or to reduce competition with herbaceous understory vegetation, in accordance with overall resource management objectives; and prescribed grazing—the controlled harvest of vegetation with grazing or browsing animals managed with the intent to achieve a specified objective. In addition, to grazing at an intensity that will maintain enough cover to protect the soil and maintain or improve the quantity and quality of desirable vegetation. When a juniper tree is cut and removed, the soil structure and the associated high infiltration rate may be maintained for over a decade (Hester, 1996). This explains why the area near the dripline usually has substantially greater forage production for many years after the tree has been cut. It also explains why runoff will not necessarily dramatically increase once juniper is removed. Rather, the water continues to infiltrate at high rates into soils previously ameliorated by junipers, thereby increasing deep drainage potential. In rangeland, deep drainage amounts can be 16 percent of the total rainfall amount per year (Thurow and Hester, 1997).