Granitic Loamy Bighorn Mountains Sub-alpine Zone
Scenario model
Current ecosystem state
Select a state
Management practices/drivers
Select a transition or restoration pathway
-
Transition T 1-2
Drought, season-long or severe grazing by livestock or large ungulates lowers the vigor of the perennial native grasses that dominate this site and encourage the native forbs to increase in prominence in the community, as well as dense spikemoss ground cover increases.
More details -
Transition T 1-3
Drought, season-long or severe grazing by livestock or large ungulates can provide the seed source and the opportunity for aggressive species to establish in this community. The lowered vigor of native species encourages the encroachment or species creep of non-native species such as Kentucky bluegrass, dandelions, and smooth brome. This also leaves the site vulnerable for invasive species such as toadflax, cheatgrass, thistles, and others to establish.
More details -
Restoration pathway R 2-1
Recovery time will be necessary with a prescribed grazing system developed specific to the forb species that are dominant and the grass species that are lost. Not all sites will recover, in extreme cases, chemical or mechanical methods with seeding may be necessary to help restore the hydrology lost with the increase in forbs and dense spikemoss ground cover.
More details -
Transition T 2-3
Drought, continued season-long grazing or severe use provides the opportunity for aggressive species to establish in this community. The weakened plant structure leaves the community vulnerable to encroachment or species creep by non-native species such as Kentucky bluegrass, dandelions, smooth brome, and in some instances conifers. This also leaves the site vulnerable for invasive species such as toadflax, cheatgrass, thistles, and others to establish.
More details -
Restoration pathway R 2-4
Communities driven by dense spikemoss, mechanical methods with seeding may be necessary to help restore the hydrology lost by the herbaceous ground cover, and to provide seed source to restore key grass species to the community.
More details -
Restoration pathway R 3-4
Integrated pest management plan and intense weed control after and possibly before seedbed preparation will be necessary to overcome a severe weed infestation. Working a location and using either improved varieties, native seed, or in some cases an introduced species suited for the management use intended may be the only way to overcome some invasive species.
More details -
Transition T 4-3
In the reclamation or restoration process, or after a land disturbance occurs, if no management is put into place to prevent a re-occurrence or a new infestation of weeds, the community will revert back or transition to an invaded state. Wildfire, prescribed burning, drought, or frequent and severe miss-use by large herbivores can be a source of the disturbance that either opens the canopy and/or introduces the species to the location.
More details -
No transition or restoration pathway between the selected states has been described
Target ecosystem state
Select a state
Description
Mixed Bunchgrass/Forbs State (State 1 - Reference) evolved with grazing by large herbivores and is well suited for grazing by domestic livestock. Potential vegetation is estimated at 75% grasses or grass-like plants, 25% forbs, and no appreciable woody plants. Specific soil characteristics within the range of the site concept will result in a shift in the vigor and dominance of specific grass species, as well as the abundance of ground-covering forbs. In soils with a higher abundance of grus in the profile will have a higher ratio of mid-stature grasses than the modal concept for this site. There is also a higher occurrence of buckwheat and phlox species on these sites.
Characteristics and indicators
The community is characterized by the key species including: Columbia needlegrass, slender wheatgrass, needleleaf sedge, Idaho fescue, and bluebunch wheatgrass. Other grasses may include mutton and Cusick’s bluegrass, bentgrasses, prairie junegrass, onespike and timber oatgrass, thickspike wheatgrass, mountain brome and spike trisetum. Forbs include: cutleaf anemone and pale mountain dandelion. Increaser species are: bluegrasses, old man’s whiskers, rosy pussytoes, lupine, field chickweed, phlox and cinquefoil (herbaceous). Mountain and fringed sagewort have been found to occur in these communities but infrequently.
Resilience management
A shift that has been seen in this community is a variation between cattle grazing and sheep grazing over time. Those allotments reviewed with long-term sheep grazing had fewer forbs by production, but still maintained a strong diversity in the understory of a tall grass dominated system. As allotments with long-term cattle grazing were reviewed, the tall grasses persisted, but had a stronger undertone of more mid-stature grasses, and a higher prominence of all forbs within the community.
Submodel
Description
This state is prominent on granitic soils. Fringed sagewort and other low or dwarf shrubs found as a minor component in this community, but forbs and grasses are the dominant cover on the landscape. Grass species that remain are mid-stature bunchgrasses that still hold a significant composition in the community but are less conspicuous and lack the production and possibly palatability of other species.
Characteristics and indicators
Lupine, balsamroot, sandwarts and phlox are common components of this community with deathcamas, paintbrush and chickweed. Idaho fescue and timber and/or Parry's oatgrass are prominant, but are less vigorous or shorter in stature than in the reference community. An increase in Dense spikemoss is prevalent and can become a total ground cover in the interspaces of plants, restricting the propagation of new plants/species; which in turn lowers the resilience of this state.
Resilience management
Research has shown that attempts to understand and find management techniques for dense spikemoss have not provided an adequate solution. Trials within the Bighorn Mountains showed that after deep ripping a site, it was able to stabilize with significant vegetation and be a functional section of rangeland with improved production, but there are still significant remnants of the spikemoss that are evident in the trial. Disagreement on the cause and cure supported that this is a degraded state within the soil characteristics, that is a stable state to an extent, but that over time without some disturbance may loose all vigor and diversity. More research is warranted before any scientific statement can be made on the resiliency and management of a spikemoss driven community.
Submodel
Description
This state is not easily divided into two distinct communities, nor is it possible to determine a typical composition of any one community. Unlike sedimentary soils, the encroachment of woody species (juniper/spruce) into the parks is not prevalent. However, dandelion, smooth brome, and Kentucky bluegrass, as well as invasive species do have opportunity for movement into degraded communities. There are instances where it is difficult to identify these communities on the landscape, especially when the community has transitioned to a high composition of forbs. The occurrence of these communities can be a process of time or of disturbance. Historic studies have shown the presence of non-natives such as Kentucky bluegrass and dandelions in a significant stature as early as 1940's and 50's. Other species such as creeping meadow foxtail, timonthy, and smooth brome are becoming more prevalent. Although it has not been documented for the purpose of ESD's at this time, large scale populations of invasive species are starting to develop on segments of the foothills of the Bighorn mountains. On an allotment basis, there are large patches of invasive species that are appearing, these areas are included in this state as a secondary community.
Characteristics and indicators
A dominant component of this state is comprised of a non-native or an invasive species. Dominant component is defined for this state as a composition of 5% or greater by weight. As species composition crosses this threshold it becomes difficult to ignore the impact on the site and is not easily or feasibly eradicated from the site. Woodland (tree) encroachment is also a component of this state, but would have to comprise at least 15% by canopy cover.
Resilience management
In this state, it is understood that the key to management of the site is finding the balance between grazing to reduce or maintain the current level of non-native or invasive species while maintaining and improving the native composition. Treatment with herbicides, biologicals, or mechanical means may be necessary to maintain current levels. The site is resilient in the sense, that once the non-native and invasive species are present, they are not eradicable.
Submodel
Description
Although more temperate in climate than the basin and foothills counter-parts, this high elevation site is arid in nature which has played a major role in the development and transitions in land use over time. Many landscapes were suppressed by fire management which has impacted forest health in general. While timber harvest has persisted on the landscape, the Bighorn Mountains provide a larger use as grazinglands. Historically, sheep were a major contributor on the range, but with time cattle are the most abundant user of this landscape.
Farming (hayland) and general agricultural practices are not a threat to the higher elevations. However, development of summer working facilities, livestock handling facilities, quarries, recreational areas, trails, roads, and recreational camp sites have played a major role in transforming the landscape. Increased access to areas and more use by humans has fostered new challenges and disturbances to the open parks and sagebrush communities.
Characteristics and indicators
This state is characterized by active disturbance (erosion, development, shifts in use) or reclamation/restoration following a disturbance. This can include roads/access recovery post timber harvest, fire recovery, etc. The plant species and composition will vary with the age of the disturbance, the seed mixes used, or the post recovery characteristics.
Resilience management
Maintaining sites once reclaimed is dependent on access, the specific prescription used to treat the land and climatic factors during the establishment and succession of the community. Restoration or managing the disturb sites for natural recovery will vary depending on what successional species establish as well as the above mentioned variables. Site specific evaluations are needed to capture the resiliency and management needs of communities within this state.
Submodel
Mechanism
Drought, season-long or severe grazing by livestock or large ungulates lowers the vigor of the perennial native grasses that dominate this site and encourage the native forbs to increase in prominence in the community. As more soil is exposed with the increased number of forbs, the dense spikemoss ground cover increases. Repeated early season grazing by cattle and elk, or by extended drought periods, grasses are reduced and forbs become the dominant cover, reducing the resiliency of this community. Seasonal fluctuations in moisture will affect the composition of species present and thus impact the grazers that can utilize the site. Larkspur is a major concern in years with a slow green up, as it will respond quickly while grasses may be slow with a slow warm up, increasing the risk of toxicity and poisoning in livestock. The same concern with lupine, in wet years, the abundance of lupine and groundsels can be significant, increasing the risk of toxicity; however, when abundant grass is present, the risk is manageable.
Mechanism
Drought, season-long or severe grazing by livestock or large ungulates weaken the perennial native vegetation that comprises this community, and provides an opening for non-native, invasive or aggressive species to encroach into the community. During dry, open winters, cold and exposure can weaken the prominent grasses within the community, and if there are seed-sources that have been carried in on livestock or wildlife, then these non-native or invasive species find a foothold to establish within the community. If the drought or use continues, and the encroached species is not addressed, it will continue to gain a hold in the community until it is unfeasible to control or eradicate it from the community. Conifer enroachment is thought to be driven more by melt off and dry down of soils during the germination and establishment of seedlings to maturity. Periods of or the cycle of drought and winter snow melt have the most significant influence with management factors serving only as a minor contribution to the soil attributes.
Constraints to recovery
The species that are moving into the reference system and the mechanism for encroachment are the two factors that will limit the ability for a site to maintain or recover. Site and time specific observations are necessary to understand the full potential of recovery for communities in this state.
Mechanism
Recovery time will be necessary with a prescribed grazing system developed specific to the forb species that are dominant and the grass species that are lost. Not all sites will have the ability to recover without significant inputs of energy and resources. In extreme cases, chemical or mechanical methods of treating the forbs on the site as well as mechanical methods to break the significant ground cover of dense spikemoss cover to permit seedling establishment. Seeding may be necessary to help restore the grass and grass-like structure and to further aid the recovery of the hydrology lost with the increase in forbs and dense spikemoss ground cover.
Context dependence
Not all communities will be hindered by a significant understory of dense spikemoss. For those communities that are, the ability to enhance or improve the community without major soil disturbance is not possible at this time. For those without this understory, the ability to use natural process to improve this site are more feasible.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Access Control |
|
|
Prescribed Grazing |
|
|
Grazing Land Mechanical Treatment |
|
|
Heavy Use Area Protection |
|
|
Integrated Pest Management (IPM) |
|
|
Upland Wildlife Habitat Management |
|
|
Early Successional Habitat Development/Management |
|
|
Prescribed Grazing |
|
|
Grazing Management Plan |
|
|
Monitor key grazing areas to improve grazing management |
|
|
Intensive Management of Rotational Grazing |
|
|
Prescriptive grazing management system for grazed lands |
Mechanism
Drought, continued season-long grazing or severe use provides the opportunity for aggressive species to establish in this community. The weakened plant structure leaves the community vulnerable to encroachment or species creep by non-native species such as Kentucky bluegrass, dandelions, smooth brome, and in some instances conifers. This also leaves the site vulnerable for invasive species such as toadflax, cheatgrass, thistles, and others to establish.
Constraints to recovery
The ability to eradicate or control non-native species without affecting the native composition is the only significant constraint of recovery to a native or less degraded plant community.
Context dependence
The specific limitations to recovery is based on which/what species are encroaching on the community and what other species are in the surrounding vicinity.
Mechanism
In the case of significant ground cover by dense spikemoss, mechanical disturbance to break up or loosen the ground cover is necessary to allow desired grasses and forbs the ability to establish. Hoof action in high intensity may be an option, but no trials were found to determine the likelihood of success. With mechanical disturbance to break up the soil cover, restoring hydrology to the site, seeding will be necessary with integrated pest management to ensure that no undesirable species move into the community. The act of tilling or breaking the soil crust alters the site, so that even after re-vegetation, the soils and hydrology will not function as an undisturbed site. The potential for the site will be shifted from the reference and further recovery will require different mechanisms to allow the soil to redevelop. This prevents this community from being reference even though it may resemble reference.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Critical Area Planting |
|
|
Prescribed Grazing |
|
|
Grazing Land Mechanical Treatment |
|
|
Range Planting |
|
|
Integrated Pest Management (IPM) |
|
|
Upland Wildlife Habitat Management |
|
|
Early Successional Habitat Development/Management |
|
|
Planned Grazing System |
|
|
Native Plant Community Restoration and Management |
|
|
Prescribed Grazing |
|
|
Grazing Management Plan |
|
|
Grazing management to improve wildlife habitat |
|
|
Intensive Management of Rotational Grazing |
|
|
Intensive rotational grazing |
|
|
Prescriptive grazing management system for grazed lands |
Mechanism
Significant treatments may be needed, including integrated pest management, soil disturbance or seeding, to eradicate the invasive species and to reclaim the community. The use of improved varieties, limited diversity in a seeding, as well as seed bed preparation and eradication processes alters the hydrology and compositional function of the system. Policy for federal and state lands sets parameters for species selection; however, a factor that determines reclamation options is limited more by the lack of seed availability for many of the native species.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Critical Area Planting |
|
|
Access Control |
|
|
Prescribed Grazing |
|
|
Grazing Land Mechanical Treatment |
|
|
Heavy Use Area Protection |
|
|
Integrated Pest Management (IPM) |
|
|
Upland Wildlife Habitat Management |
|
|
Early Successional Habitat Development/Management |
|
|
Planned Grazing System |
|
|
Native Plant Community Restoration and Management |
|
|
Prescribed Grazing |
|
|
Invasive Plant Species Control |
|
|
Grazing Management Plan |
|
|
Improve the plant diversity and structure of non-cropped areas for wildlife food and habitat |
|
|
Biological suppression and other non-chemical techniques to manage herbaceous weeds invasive species |
|
|
Prescriptive grazing management system for grazed lands |
Mechanism
Following a ground disturbance, whether planned or incidental in nature, provides a niche for non-native species to establish. This same niche is an opportunity for non-typical natives (juniper/spruce) to encroach into the area. Disturbance by means of equipment, vehicles, or human activity, as well as domestic animals and wildlife provide a means for introducing seed sources for these undesirable species into the system.
Planned disturbances, seeding or development activities provides the open niche for invasive species to establish in an area. Ground disturbances of any nature introduces seed sources from surrounding areas into a prime seedbed. In the reclamation or restoration process, if no management is put into place to prevent an infestation of weeds, the community will transition (or possibly revert back) to an invaded state. Wildfire, prescribed burning, drought, or frequent and severe over-use by large herbivores can be a source of the disturbance that either opens the canopy and/or introduces the species to the location. Extended periods of non-use creates a decadent community with a large proportion of dead growth persisting around the crown of the plants, reducing vigor and production. As the plants begin to die-back, the community becomes vulnerable to weed invasions. This invasion triggers the transition to an invaded state.
Context dependence
Once the soils of a community are mechanically altered, the community will no longer function or respond as an undisturbed soils. Although it may be very similar, there will be subtle differences. For this transition, soil disturbance has occurred, but the function or driver for State 3 is a response to the non-native or invasive species, not to the soil properties.
Model keys
Briefcase
Add ecological sites and Major Land Resource Areas to your briefcase by clicking on the briefcase (
) icon wherever it occurs. Drag and drop items to reorder. Cookies are used to store briefcase items between browsing sessions. Because of this, the number of items that can be added to your briefcase is limited, and briefcase items added on one device and browser cannot be accessed from another device or browser. Users who do not wish to place cookies on their devices should not use the briefcase tool. Briefcase cookies serve no other purpose than described here and are deleted whenever browsing history is cleared.
Ecological sites
Major Land Resource Areas
The Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.