State 1
Indian Ricegrass / Yucca

Community 1.1
Indian Ricegrass / Yucca

This plant community results from little or no use and no fires over an extended period in the HCPC. Mid and tall 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, prairie sandreed, and rhizomatous wheatgrasses. Forbs commonly found in this plant community include scarlet globemallow, fringed sagewort, lemon scurfpea, parsnipflower buckwheat, sandwort, smooth woodyaster, and phlox. When compared to the Historic Climax Plant Community, yucca has significantly increased. Indian ricegrass and winterfat have also increased. Prairie sandreed, silver sagebrush and some forbs have decreased. Total production remains about the same but due to the increase in yucca available forage may be slightly less. The total annual production (air-dry weight) of this state is about 500 pounds per acre, but it can range from about 350 lbs./acre in unfavorable years to about 700 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 can show signs of maturation and decadence. Additional plant litter, if significant on the soil surface, may affect live plants and/or prohibiting 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 2
Perennial Grass/ Mixed shrub

Community 2.1
Perennial Grass/ Mixed shrub

Historically, this plant community evolved under grazing by bison and a low fire frequency. Currently, this site normally is found under a moderate, season-long grazing regime and extended periods without fire is now common. Prolonged drought can also play an important role under these grazing regimes and will exacerbate these conditions. Shrubs such as silver and big sagebrushes, yucca, and green rabbitbrush, make up less than 25% of the total annual production. Mid and tall perennial grasses make up the majority of the understory with the balance made up of short warm-season grasses, and miscellaneous forbs. The understory of grass and grass-like plants includes needleandthread, prairie sandreed, rhizomatous wheatgrasses, blue grama, threadleaf sedge, and red threeawn. Forbs commonly found in this plant community include scarlet globemallow, fringed sagewort, lemon scurfpea, sulfur buckwheat, sandwort, hairy goldaster, and phlox. The overstory of sagebrush and understory of grass and forbs provide a diverse plant community. When compared to the Historic Climax Plant Community, Indian ricegrass and winterfat have decreased. Indian ricegrass may occur in only trace amounts under the sagebrush canopy or within the patches of pricklypear. Threadleaf sedge, blue grama, big and silver sagebrush, and yucca have increased. Plains pricklypear cactus will also have increased, but occurs only in small patches. The total annual production (air-dry weight) of this state is about 400 pounds per acre, but it can range from about 200 lbs./acre in unfavorable years to about 525 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, will convert the plant community to the Blowout Dune/Mixed Shrub Plant Community.

State 3
Blowout Dune/ Mixed Shrub

Community 3.1
Blowout Dune/ Mixed Shrub

This plant community is the result of Frequent and severe grazing and protection from fire. Bare sand and shrubs dominates this plant community, as the annual production of sagebrush, green rabbitbrush and yucca will exceed 25%. Yucca can become a dominant plant on this site especially if browsing of the yucca during the bloom growth stage is removed. These shrub species are a significant component of the plant community and the preferred cool season grasses have been eliminated or greatly reduced. The dominant grasses are Sandberg bluegrass, 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 as well as total production is significantly reduced. The total annual production (air-dry weight) of this state is about 150 pounds per acre, but it can range from about 100 lbs./acre in unfavorable years to about 300 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 herbivore use and blowing sand, which can defoliate the vegetative parts of the grass plants. The soils are not protected from wind as erosion is accelerated and blowouts will increase. Pedestalling is pervasive and eolian deposits (dunes) form around the clumped vegetation. This situation is normally extensive. Transitions or pathways leading to other plant communities are as follows: • Deferment or very long-term grazing prescribed grazing, will convert this plant community to the Needleandthread/Threadleaf Sedge/Yucca Vegetative State.

State 4
Needleandthread/Prairie Sandreed

Community 4.1
Needleandthread/Prairie Sandreed

The interpretive plant community for this site is the Historic Climax Plant Community. This state evolved with grazing by large herbivores and periodic fires. The cyclical natural of the fire regime in this community prevented big sagebrush from being the dominant landscape. This plant community can be found on areas that are properly managed with grazing and/or prescribed burning, and on areas receiving occasional short periods of rest. The state is a mix of warm and cool season mid and tall grasses. Potential vegetation is about 75% grasses or grass-like plants, 10% forbs, and 15% woody plants. The major grasses include needleandthread, prairie sandreed, and Indian ricegrass. Other grasses occurring in the state include rhizomatous wheatgrasses, Sandberg bluegrass, blue grama, threeawns, and threadleaf sedge. Fourwing saltbush, winterfat and silver and big sagebrush are conspicuous components of this state. A variety of forbs also occurs in this state and plant diversity is high (see Plant Composition Table). The total annual production (air-dry weight) of this state is about 500 pounds per acre, but it can range from about 350 lbs./acre in unfavorable years to about 700 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 5
Needleandthread/Threadleaf Sedge/Yucca

Community 5.1
Needleandthread/Threadleaf Sedge/Yucca

This plant community can occur where the Blowout Dune/Mixed Shrub Plant Community is deferred from grazing or under very long term prescribed grazing practices. Shrubs and especially yucca remain a significant component of the plant community but grasses such as needleandthread and threadleaf sedge have reestablished on the bare sands areas. A sod of these grasses may even dominate this site. Pricklypear cactus can also become established in dense patches. The shrub and especially yucca component is present but is mostly localized to the original areas 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. Noxious weeds such as Russian Knapweed may also remain if not treated. The interspaces between plants will have diminished in size. When compared with the HCPC or the Mixed Shrub/ Perennial Grass 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 250 pounds per acre, but it can range from about 100 lbs./acre in unfavorable years to about 325 lbs./acre in above average years. This community is somewhat 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 vegetative 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.