State 1
Grassland State

The Grassland State defines the ecological potential and natural range of variability resulting from the natural disturbance regime of the Choppy Sands 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. These events are part of the natural disturbance regime and climatic process. The Reference Plant Community consists of warm-season tall- and midgrasses, cool-season and sod-forming grasses, forbs, and shrubs. The Midgrass community is made up primarily of warm-season midgrasses with an interspersed cool-season component and decreasing amounts of forbs and tallgrasses.

Characteristics and indicators. The Grassland State is dominant of tall- and midgrasses. Woody encroachment will be less than 15 percent canopy cover. This state has no indication of mechanical tillage in the soil profile or within the plant composition.

Resilience management. Providing a forage and animal balance, prescribed burning, brush management, and periodic rest during the growing season will help sustain this state and avoid a transition.

Community 1.1
Reference Plant Community

Figure 11. Reference Plant Community Reno, County Kansas.

Figure 12. This is an example of blowout on the Choppy Sands ecological site in Stafford, County Kansas.

The interpretive plant community for this site is the Reference Plant Community, which represents the original plant community that existed prior to European settlement. The site is characterized as a grassland, essentially free of trees and large shrubs. It is dominated by tall, warm-season grasses including sand bluestem, switchgrass, Indiangrass, and giant sandreed. The major midgrass is little bluestem. Combined, these grasses will account for 70-80 percent of the vegetation produced annually. Other prevalent midgrasses are Canada wildrye, sand lovegrass, composite dropseed, sand dropseed, and purple lovegrass. Scattered throughout this plant community are minor amounts of shortgrasses such as blue grama, hairy grama, thin paspalum, and Carolina crabgrass. The site supports a wide variety of legume species, which are interspersed throughout the grass sward. The most abundant are roundhead lespedeza, slender lespedeza, sessile leaf tick trefoil, golden prairie clover, lemon scurfpea, silky sophora, and prairie bundleflower. Other important forbs include Maximilian sunflower, scaley blazing star, stiff goldenrod, and pitcher sage. Leadplant and Jersey tea are low-growing shrubs that occur over the site. Unlike most shrubs, these plants are both quite tolerant to fire. A few small clumps of Chickasaw plum and skunkbush may be found on the steeper slope exposures of dunes, where they partially escape the effects of intense fires. This is a stable plant community when adequately managed. A prescribed grazing program that incorporates periods of deferment during the growing season benefits the tallgrasses and the palatable forb species. Soils are susceptible to wind erosion and excessive grazing while livestock trailing can quickly have impact on soil stability and lead to an occurrence of small blowouts.

Resilience management. A prescribed grazing program that incorporates periods of deferment during the growing season benefits the tallgrasses and the palatable forb species.

Community 1.2
Midgrass Plant Community

Figure 15. Midgrass Plant Community Reno, County Kansas.

This plant community developed as a result of many years of continuous overgrazing. Midgrasses dominate the site and comprise 60-70 percent of the annual production. The dominant midgrass is little bluestem. Sand dropseed, composite dropseed, sand lovegrass, purple lovegrass, and blowout grass can be found on the site. Shortgrasses such as Carolina crabgrass, red lovegrass, tumble windmillgrass, purple threeawn, hairy grama, and blue grama produce 10-15 percent of the vegetation. There are trace amounts of sand bluestem, switchgrass, Indiangrass, and giant sandreed. A number of midgrasses are dominant over the taller grasses and have been reduced by overgrazing. These include sand dropseed, sand lovegrass, purple lovegrass, thin paspalum, and composite dropseed. Forbs such as Maximilian sunflower, roundhead lespedeza, prairie bundleflower, and golden prairie clover have largely been replaced by white sagebrush, Cuman ragweed, Fendler’s aster, redroot buckwheat, and tenpetal blazingstar. Forbs produce 10-12 percent of the total herbage. This site supports a few shrubs. Leadplant and Jersey tea may be scattered throughout the site. Chickasaw plum and skunkbush sumac are usually found in small clumps (motts). Shrubs usually will not comprise over 5 percent of the total annual production. Total annual production ranges from 1,500 to 3,000 pounds of air-dry vegetation per acre and averages about 2,000 pounds. Prescribed grazing that incorporates periods of deferment during the growing season will improve the vigor and gradual recovery of the more palatable tallgrasses and forbs.

Resilience management. Periods of deferment from grazing are essential in maintaining this as a stable plant community. Sand bluestem is preferred, and readily selected and grazed by cattle. When the site is grazed continuously throughout the growing season, sand bluestem is usually overgrazed and thus maintained in a state of low vigor. This results in a gradual reduction in abundance over time. Even under moderate continuous stocking, livestock can locate and severely overgraze the tops or crests of sand dunes. Where this occurs, sand dropseed, thin paspalum, and mat sandbur replace the taller grasses. In some areas this has lead to small blowouts.

Pathway 1.1 to 1.2
Community 1.1 to 1.2

Reference Plant Community

Midgrass Plant Community

The following describes the mechanisms of change from Plant Community 1.1 to Plant Community 1.2. These mechanisms include management controlled by repetitive heavy use, no rest or recovery of the key forage species, no forage and animal balance for many extended grazing seasons. This type of management for periods greater than 10 years will shift functional and structural plant group dominance towards Plant Community 1.2.

Pathway 1.2 to 1.1
Community 1.2 to 1.1

Midgrass Plant Community

Reference Plant Community

The following describes the mechanisms of change from Plant Community 1.2 to Plant Community 1.1. Management (10-15 years) that includes adequate rest and recovery of the key forage species (sand bluestem, switchgrass, and Indiangrass) 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.

State 2
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 percent from a lack of fire according to a study from 1937 to 1969, in contrast to a 1 percent increase on burned areas (Bragg and Hulbert, 1976). Periodic burning tends to hinder the establishment of most woody species and favors forbs and grasses. However, it should be pointed out that not all unburned areas have a woody plant invasion. Hydrologic function is affected by the amount of vegetative cover. Canopy interception loss can vary from 25.4 percent to 36.7 percent (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 base of trees are considerably higher than losses associated with the canopy. The decomposed material retains approximately 40 percent 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. 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. 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. This state has a dominant woody canopy cover of greater than 20 percent.

Resilience management. Prescribed burning and mechanical brush control is necessary to maintain a Grassland State.

Community 2.1
Shrub Community

Figure 16. Shrub plant community in Reno, County Kansas.

This plant community is dominated by shrubs consisting primarily of Chickasaw plum, skunkbush sumac, and smooth sumac. Sand sagebrush occurs in some locations in the extreme western portion of the Major Land Resource Area 79. Trees such as honeylocust (Gleditsia triacanthos) and eastern redcedar (Juniperus virginiana) have invaded and become established in isolated areas. Chickasaw plum is generally the most abundant shrub and typically forms large mottes or thickets scattered over the site. Shrubs and trees may produce 40-60 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 forb and grass species. However, not all unburned areas have a woody plant problem. The speed of encroachment varies considerably. Birds are instrumental in the distribution of seed and accelerating the spread of shrub and tree species over the site. Encroachment may be on areas subjected to long-term continuous overgrazing. In these situations the associated grasses will usually consist of sand dropseed, sand lovegrass, purple lovegrass, Texas bluegrass, 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 accumulations 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 usually include sand bluestem, little bluestem, Indiangrass, switchgrass, sedges, and Canada wildrye. Grass production is significantly reduced because of the shrub competition. Grass yields vary from 40-50 percent of the total vegetative production. Forbs generally produce 15-20 percent of the total. Major forbs include white sagebrush, Carruth's sagewort, redroot buckwheat, Cuman ragweed, lemon scurfpea, camphorweed, and tenpetal blazingstar. Total annual production ranges from 1,000 to 2,500 pounds air dry vegetation per acre and averages about 1,500 pounds. Usually a prescribed burning program accompanied with prescribed grazing will gradually return the plant community to one dominated by grasses and forbs. Special planning will be necessary to assure that sufficient amounts of fine fuel are available to carry fires with the intensity to control the woody species. In some locations use of chemicals as a brush management tool will be necessary to initiate and accelerate this transition. Many species of wildlife, especially bobwhite quail and whitetail deer, benefit from the growth of shrubs for food and as cover. When wildlife populations are a desirable component, this should be considered in any brush management plans.

Resilience management. This plant community is maintained by a lack of fine fuel loads, prescribed fire, and mechanical brush control.

State 3
Tillage State

The Tillage State consists of abandoned cropland that has been naturally revegetated ("go-back land") 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). 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).

Characteristics and indicators. Bulk density, aggregate stability, soil structure changes and plant functional and structural groups will distinguish this state from the others.

Resilience management. This state has no restoration pathways and will maintain in this state.

Community 3.1
Reseed 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 eastern redcedar and eastern cottonwood. Occasional burning is effective in controlling establishment of these woody plants.

Resilience management. This is a stable plant community when adequately managed. A prescribed grazing program that incorporates periods of deferment, during the growing season, benefits the reseeded grasses and the palatable forb species. Soils are susceptible to wind erosion and excessive grazing while livestock trailing can quickly have impact on soil stability and lead to an occurrence of small blowouts.

Community 3.2
Go-back 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 upon 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 windmill grass. 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, and with prescribed grazing management, other perennial grasses and forbs common in the Reference Plant Community return to the site. Some go-back areas are invaded by trees and shrubs. The more common include eastern redcedar and eastern cottonwood. Occasional burning is effective in controlling these woody plants. Total annual production varies by site. This depends upon seasonal precipitation and the stage of plant succession in the plant community.

Resilience management. This is a stable plant community when adequately managed. A prescribed grazing program that incorporates periods of deferment during the growing season benefits the native palatable go-back species and the palatable forb species. Soils are susceptible to wind erosion and excessive grazing while livestock trailing can quickly have impact on soil stability and lead to an occurrence of small blowouts.

Transition 1 to 2
State 1 to 2

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 a reduction 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). Tree and shrub establishment becomes increasingly greater while fine fuel loads decrease. As trees and shrubs increase at levels of greater than 20 percent canopy cover, the processes and functions that allow the Woody State to become resilient are active and dominant over the processes and systems inherent of the Grassland State. Using prescribed fire as a standalone management tool is unsuccessful to eradicate the trees and shrubs due to a lack of fine fuel loads.

Constraints to recovery. Canopy cover of woody vegetation is greater than 20 percent. The woody species competes with the native grass fine fuel loads that would naturally be capable to carry a fire and maintain the prairie ecosystem.

Transition 1 to 3
State 1 to 3

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

Constraints to recovery. The resilience of the Reference State has been compromised by the fracturing and blending of the native virgin sod.

Restoration pathway 2 to 1
State 2 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).