State 1
Needleandthread/Indian ricegrass

Community 1.1
Needleandthread/Indian ricegrass

The interpretive plant community for this site is the Historic Climax Plant Community. This state evolved with grazing by large herbivores, soils less than 10 inches in depth, and low fire frequency. Cool season midgrasses are the primary vegetation in this state but shrubs and forbs are also prominent. Potential vegetation is about 50% grasses or grass-like plants, 25% forbs, and 25% woody plants. This state is found on areas that are properly managed and on areas receiving occasional short periods of rest. The major grasses include needleandthread, Indian ricegrass, and rhizomatous wheatgrasses. Other grasses occurring on the state include bluebunch wheatgrass, prairie sandreed, sand dropseed, Sandberg bluegrass, and threadleaf sedge. Skunkbush sumac is a conspicuous component of this state. A variety of forbs and shrubs also occur in this state and plant diversity is high (see Plant Composition Table). The total annual production (air-dry weight) of this state is about 175 pounds per acre, but it can range from about 75 lbs./acre in unfavorable years to about 250 lbs./acre in above average years. The state is stable and well adapted to the Northern Great Plains climatic conditions. The diversity in plant species allows for high drought resistance. This is a sustainable plant community (site/soil stability, watershed function, and biologic integrity). Transitions or pathways leading to other plant communities are as follows: • Moderate, Continuous Season-Long grazing will convert the plant community to the Perennial Grass/Mixed Shrub Plant Community. Prolonged Drought will exacerbate this transition. • Protection from grazing and fire will convert this plant community to the Indian Ricegrass/Yucca Vegetation State.

State 2
Yucca/ Indian Ricegrass

Community 2.1
Yucca/ Indian Ricegrass

This plant community results from little or no use and no fires over an extended period in the HCPC. Mid perennial grasses make up the majority of the understory and the overstory is dominated by yucca. The understory of grass and grass-like plants includes Indian ricegrass, needleandthread, and rhizomatous wheatgrasses. Forbs commonly found in this plant community include Badlands mule's-ears, scarlet globemallow, fringed sagewort, lemon scurfpea, sulphur flower buckwheat, sandwort, rush skeletonweed, and phlox. When compared to the Historic Climax Plant Community, yucca has significantly increased. Indian ricegrass has also increased. Needleandthread and some forbs have decreased. Total production has remained about the same but due to the increase in yucca less forage is available. The total annual production (air-dry weight) of this state is about 175 pounds per acre, but it can range from about 75 lbs./acre in unfavorable years to about 225 lbs./acre in above average years. The state persists if management remains constant and fires are suppressed. The diversity in plant species allows for high drought resistance. Individual grass plants may show signs of maturation and decadence. Additional plant litter if significant on the soil surface may affect live plants and/or prohibit regeneration of new seedlings, which may lead to plant mortality and an increase in the amount of bare ground. The extent of these conditions, however, depends on the duration of nonuse and absence of fire. Soils are mostly stable and the surface shows minimum soil loss. The watershed is functioning and the biotic community is mostly intact. Transitions or pathways leading to other plant communities are as follows: • Brush management or wildfire + prescribed grazing, will convert the plant community to near HCPC. • Brush management or wildfire + frequent and severe grazing, will convert the plant community to a Blowout Dune/Mixed Shrub Vegetative State. Although many of these shrubs are susceptible to brush control, recolonization will occur quickly. Grazing will remove entire herbaceous plants including the root system due to the plants inability to anchor to these coarser soils. Without these plants, shrubs will have a competitive advantage. In addition, the lack of cover will invite wind erosive processes to occur leaving the soil susceptible to wind-scouring and deposition.

State 3
Perennial Grass/ Mixed Shrub

Community 3.1
Perennial Grass/ Mixed Shrub

Historically, this plant community evolved under grazing and a low fire frequency. Currently, it is found under moderate, season-long grazing by livestock and will be exacerbated by prolonged drought conditions. In addition, the fire regime for this site has been modified and extended periods without fire is now common. This plant community is still dominated by cool-season mid grasses, while short warm-season grasses and miscellaneous forbs account for the balance of the understory. The overstory is comprised of a variety of shrubs. The dominant grasses and grasslikes include needleandthread, rhizomatous wheatgrasses, threadleaf sedge, Sandberg bluegrass, sand dropseed, Fendler threeawn, and blue grama. Forbs commonly found on the site include badlands mules-ear, waxleaf penstemon, little larkspur, sulfur flower buckwheat, rush skeletonweed, miner's candle, and lemon scurfpea. Shrubs can make up to 35% of the annual production. These include skunkbush sumac, silver sagebrush, yucca, and green rabbitbrush. The overstory of shrubs and understory of grass and forbs provide a diverse plant community. When compared to the Historic Climax Plant Community, Indian ricegrass has decreased. Indian ricegrass may occur in only trace amounts under the brush canopy or within the patches of pricklypear. Threadleaf sedge, blue grama, big sagebrush, skunkbush sumac and a variety of forbs have increased. Plains pricklypear cactus will also have increased, but occurs only in small patches. Total production is less as the mid cool season grasses are replaced with short warm season grasses. The total annual production (air-dry weight) of this state is about 125 pounds per acre, but it can range from about 50 lbs./acre in unfavorable years to about 200 lbs./acre in above average years. This plant community is resistant to change. The herbaceous species present are well adapted to grazing; however, species composition can be altered through long-term overgrazing. The herbaceous component is mostly intact and plant vigor and replacement capabilities are sufficient. Incidence of pedestalling is minimal. Soils are mostly stable, but areas of wind-scouring and deposition are noticeable in small patches. The watershed is functioning and the biotic community is intact. Transitional pathways leading to other plant communities are as follows: • Prescribed grazing and possibly long-term prescribed grazing is needed to return this state to near Historic Climax Plant Community condition. • Frequent and severe grazing and no fire, will convert the plant community to the Blowout Dune/Mixed Shrub Plant Community.

State 4
Blowout Dune/Mixed Shrub

Community 4.1
Blowout Dune/Mixed Shrub

This plant community is the result of Frequent and severe grazing and protection from fire. Bare sand and shrubs dominate this plant community, as the annual production of skunkbush sumac, green rabbitbrush and yucca will exceed 35%. Skunkbush sumac, yucca, and badlands mule's-ears become dominant plants on this state. These plant species are significant components of the plant community and the preferred cool season grasses have been eliminated or greatly reduced. The dominant grasses and grasslikes are sand dropseed, Fendler threeawn, threadleaf sedge, and blue grama. Weedy annual species such as cheatgrass, Russian thistle, kochia, and a variety of mustards may occupy the site if seed sources are available. Patches of pricklypear cactus can be noticeable. The interspaces between plants have expanded leaving the amount of bare ground more prevalent. Grass production is significantly reduced as has the amount of available forage, but the total production is only slightly lower as the amount of production from shrubs has increased. The total annual production (air-dry weight) of this state is about 100 pounds per acre, but it can range from about 35 lbs./acre in unfavorable years to about 175 lbs./acre in above average years. This plant community is relatively resistant to change. Continued frequent and severe grazing does not seem to affect the plant composition or structure of the plant community. These areas are more resistant to fire as less fine fuels are available and the bare ground between the shrub plants is increased. Plant diversity is poor. Production is reduced and plant vigor is diminished due to blowing sand, which can defoliate the vegetative parts of the grass plants. The soils are exposed to wind as erosion is accelerated and blowouts increase. Pedestalling is pervasive and eolian deposits (dunes) form around the clumped vegetation. This situation is normally extensive. Transitional pathways leading to other plant communities are as follows: • No use or very long-term grazing prescribed grazing, will convert this plant community to the Needleandthread/Threadleaf Sedge/Yucca Vegetative State.

State 5
Needleandthread/Threadleaf sedge/Skunkbush Sumac

Community 5.1
Needleandthread/Threadleaf sedge/Skunkbush Sumac

This plant community can occur where the Blowout Dune/Mixed Shrub Plant Community is reseeded with mulch and/or rested or a prescribed grazing long-term management practice is implemented. Skunkbush sumac and possibly yucca remain significant components of the plant community, but grasses such as needleandthread and threadleaf sedge have reestablished on the bare sand areas. A sod of these grasses may even dominate this site. Pricklypear cactus can also become established in dense patches. The skunkbush sumac and yucca are present but are mostly localized to the original areas occupied on the ridgeline of the dunes. The blowout areas and dune slopes are now mostly covered with needleandthread and threadleaf sedge. Other important grasses besides the needleandthread and threadleaf sedge are the rhizomatous wheatgrasses when present, Fendler threeawn, Sandberg bluegrass and blue grama. Patches of annuals such as cheatgrass and other weedy annual forbs such as halogeton, Russian thistle, and kochia will persist on this site if not treated. The interspaces between plants will have diminished in size. When compared with the HCPC or the Perennial Grass/ Mixed Shrub Plant Communities, the annual production is less. Most of the climax grasses are not present such as Indian ricegrass and prairie sandreed. The total annual production (air-dry weight) of this state is about 125 pounds per acre, but it can range from about 50 lbs./acre in unfavorable years to about 180 lbs./acre in above average years. This sod is some what resistant to change under moderate grazing and the reestablishment of perennial mid and tall grasses is difficult in this situation. The biotic integrity of this state is minimally functional and plant diversity is moderate to low. Erosion has been diminished as the sodded areas are resistant to wind erosive processes. The remnant dune formations should not be confused with current wind erosion processes. Pedestalling is still apparent along the sod edges, but is not progressing. Transitional pathways leading to other plant communities are as follows: • Reseeding with mulch with brush management and prescribed grazing, is necessary to return a protective vegetation cover to this state so as to convert this to near HCPC. The grazing prescription most commonly used is complete deferment during the growing season, with limited use in the winter. This will provide as much plant litter cover as possible to protect the soil surface. • Frequent and severe grazing will return the plant community to the Blowout Dune/Mixed Shrub Plant Community.