State 1
Reference State

The Reference State (1) includes the plant communities that were best adapted to the unique combination of factors associated with this ecological site prior to European settlement. The site was in a natural dynamic equilibrium with the historic biotic, abiotic, and climatic factors at the time of European immigration and settlement. The dominant aspect of the plant community is Bonneville big sagebrush and bluebunch wheatgrass. The community is made up of 55 percent grasses, 25 percent forbs, and 20 percent shrubs, on a dry weight base.

Characteristics and indicators. This state will only have native species in the plant community.

Community 1.1
Bonneville Big Sagebrush ≥ Perennial Cool-season Grasses ≥ Forbs ≥ Other Native Shrubs

This community is described in the initial plant list. This community is represented with 55 percent grasses, 25 percent forbs, and 20 percent shrubs. The dominant shrub, visually and in production, is Bonneville big sagebrush. The dominant grass is bluebunch wheatgrass, and the dominant forb, visually, is arrowleaf balsamroot. This community has approximately 10 to 15 percent bare ground and surface rock fragments.

Community 1.2
Bonneville big sagebrush ≥ Other Native Shrubs ≥ Perennial Cool Season Grasses = Forbs

This community appears when the Bonneville big sagebrush increases enough to suppress the herbaceous understory and other shrubs, such as mountain snowberry, antelope bitterbrush, and Utah serviceberry. This community has approximately 10 to 20 percent bare ground and surface rock fragments.

Community 1.3
Antelope bitterbrush ≥ Perennial Cool Season Grasses ≥ Forbs ≥ Fire Tolerant Shrubs

This plant community occurs after a fire event (usually mid-temperature, fast moving fire associated with a summer convection thunderstorm. After the fire event, the Bonneville big sagebrush has been removed and replaced with antelope bitterbrush. Recovery of the Bonneville big sagebrush in this community phase may take 5 to 10 year, along with a proper episodic weather event year.

Community 1.4
Perennial Cool Season Grasses ≥ Forbs ≥ Fire Tolerant Shrubs

This community usually occurs when an intense fast-moving fire heats the ground and damages the antelope bitterbrush changing the dominant plant community. The plant community is represented with 65 percent grasses, 25 percent forbs, and 10 percent shrubs. This community will likely have approximately 15 to 20 percent bare ground and surface rock fragments.

Pathway 1.1a
Community 1.1 to 1.2

This pathway occurs over time and without a catastrophic event. This pathway may be dependent on a specific chain of climatic events.

Pathway 1.1b
Community 1.1 to 1.3

This pathway occurs during a fire event, normally in mid-summer, when the fire is hot enough, and moves fast enough to kill the sagebrush and stimulate antelope bitterbrush growth.

Pathway 1.1c
Community 1.1 to 1.4

This pathway occurs when fire, insects, prolonged drought, and/or pathogens that kill, reduce the dominant shrub overstory. Fire is the most effective of these disturbances.

Pathway 1.2a
Community 1.2 to 1.3

This pathway occurs during a fire event, normally in mid-summer, when the fire is hot enough, and moves fast enough to kill the sagebrush and stimulate antelope bitterbrush growth.

Pathway 1.2b
Community 1.2 to 1.4

This pathway occurs when fire, insects, prolonged drought, and/or pathogens that kill, reduce the dominant shrub overstory. Fire is the most effective of these disturbances.

Pathway 1.3b
Community 1.3 to 1.1

This pathway occurs over time and without a catastrophic event. This pathway may be dependent on a specific chain of climatic events.

Pathway 1.3a
Community 1.3 to 1.4

This pathway occurs when fire, insects, prolonged drought, and/or pathogens, reduce the dominant shrub overstory. Fire is the most effective of these disturbances.

Pathway 1.4a
Community 1.4 to 1.1

Time without catastrophic event. This was probably dependent on a specific chain of climatic events.

State 2
Current Potential State

The Current Potential State (2) includes the biotic communities that would become established on the ecological site if all successional sequences were completed without human interference under the present environmental conditions. Natural disturbances are inherent in its development. This State may include acclimatized, naturalized, or invasive non-native species. There is no known way to effectively remove these plants from the site once they have become established. The level of occurrence of these plants is such that careful management can prevent their domination of the site. This site is irreversibly changed. Plant communities within the Current Potential State (2) may be managed and used for various purposes without significant alteration in plant community composition or production. It includes all of the plant communities that exist in the Reference State (1) with the inclusion of species that are non-native to this ecological site. All of these scenarios are very interrelated and dependent on weather patterns and events as well as fire frequency and intensity. The fire interval frequency is approximately 30 to 55 years. Any set of events that are strong enough to force the plant community out of this pattern can push it over a threshold and into another ecological state.

Characteristics and indicators. This state will be similar in community composition and dynamics to the Reference State with the exception of the inclusion of non-native species.

Community 2.1
Bonneville big sagebrush ≥ Perennial Cool Season Grass ≥ Forbs ≥ Other Native Shrubs ≥ Non-Native Species

This plant community is described in the initial plant list. This community is represented with 55 percent grasses, 25 percent forbs, and 20 percent shrubs. The dominant shrub, visually and in production, is Bonneville big sagebrush. The dominant grass is bluebunch wheatgrass and the dominant forb, visually, is arrowleaf balsamroot. This community has approximately 10 to 15 percent bare ground and surface rock fragments. This community has notable amounts of non-native species.

Community 2.2
Bonneville Big Sagebrush ≥ Other Native Shrubs ≥ Perennial Cool-season Grass ≥ Forbs ≥ Non-native Species

This plant community appears when the Bonneville big sagebrush increases, suppressing the herbaceous understory and other shrubs such as mountain snowberry, antelope bitterbrush, and Utah serviceberry. This community has approximately 10 to 20 percent bare ground and surface rock fragments. This community has notable amounts of non-native species.

Community 2.3
Antelope Bitterbrush ≥ Perennial Cool-season Grass ≥ Forb ≥ Fire Tolerant Shrub ≥ Non-Native Species

This plant community appears after a fire (usually a mid-temperature, fast moving fire, typically associated with summer convection thunderstorms). The Bonneville big sagebrush is replaced with antelope bitterbrush. Recovery of the Bonneville big sagebrush in this community will take approximately 5 to 10 years, along with a proper episodic weather event year. This community has notable amounts of non-native species.

Community 2.4
Perennial Cool-season Grass ≥ Forbs ≥ Fire Tolerant Shrubs ≥ Non-Native Species

Figure 12. State 2 Community Phase 2.4: Recent burn in a healthy bluebunch wheatgrass community. Location: Portage, Utah. T14N, R4W, S1, NW1/4. Photo taken by Keith Wadman 1/9/2007

This community usually occurs after an intense fire that damages and reduces the antelope bitterbrush, The plant community is represented with 65 percent grasses, 25 percent forbs, and 10 percent shrubs. This community has notable amounts of non-native species.

Pathway 2.1a
Community 2.1 to 2.2

Bonneville big sagebrush ≥ Perennial Cool Season Grass ≥ Forbs ≥ Other Native Shrubs ≥ Non-Native Species

Bonneville Big Sagebrush ≥ Other Native Shrubs ≥ Perennial Cool-season Grass ≥ Forbs ≥ Non-native Species

This pathway occurs over time and without a catastrophic event. This pathway may be dependent on a specific chain of climatic events.

Pathway 2.1b
Community 2.1 to 2.3

Bonneville big sagebrush ≥ Perennial Cool Season Grass ≥ Forbs ≥ Other Native Shrubs ≥ Non-Native Species

Antelope Bitterbrush ≥ Perennial Cool-season Grass ≥ Forb ≥ Fire Tolerant Shrub ≥ Non-Native Species

This pathway occurs during a fire event, normally in mid-summer, when the fire is hot enough, and moves fast enough to kill the sagebrush and stimulate antelope bitterbrush growth.

Pathway 2.1c
Community 2.1 to 2.4

Bonneville big sagebrush ≥ Perennial Cool Season Grass ≥ Forbs ≥ Other Native Shrubs ≥ Non-Native Species

Perennial Cool-season Grass ≥ Forbs ≥ Fire Tolerant Shrubs ≥ Non-Native Species

This pathway occurs when disturbances such as fire, insects, prolonged drought, pathogens, and/or overgrazing reduce the dominant shrub overstory. Fire and overgrazing are the most common of these disturbances.

Pathway 2.2a
Community 2.2 to 2.3

Bonneville Big Sagebrush ≥ Other Native Shrubs ≥ Perennial Cool-season Grass ≥ Forbs ≥ Non-native Species

Antelope Bitterbrush ≥ Perennial Cool-season Grass ≥ Forb ≥ Fire Tolerant Shrub ≥ Non-Native Species

This pathway occurs during a fire event, normally in mid-summer, when the fire is hot enough, and moves fast enough to kill the sagebrush and stimulate antelope bitterbrush growth.

Pathway 2.2b
Community 2.2 to 2.4

Bonneville Big Sagebrush ≥ Other Native Shrubs ≥ Perennial Cool-season Grass ≥ Forbs ≥ Non-native Species

Perennial Cool-season Grass ≥ Forbs ≥ Fire Tolerant Shrubs ≥ Non-Native Species

This pathway occurs when disturbances such as fire, insects, prolonged drought, pathogens, and/or overgrazing reduce the dominant shrub overstory. Fire and overgrazing are the most common of these disturbances.

Pathway 2.3b
Community 2.3 to 2.1

Antelope Bitterbrush ≥ Perennial Cool-season Grass ≥ Forb ≥ Fire Tolerant Shrub ≥ Non-Native Species

Bonneville big sagebrush ≥ Perennial Cool Season Grass ≥ Forbs ≥ Other Native Shrubs ≥ Non-Native Species

This pathway occurs over time and without a catastrophic event. This pathway may be dependent on a specific chain of climatic events.

Pathway 2.3a
Community 2.3 to 2.4

Antelope Bitterbrush ≥ Perennial Cool-season Grass ≥ Forb ≥ Fire Tolerant Shrub ≥ Non-Native Species

Perennial Cool-season Grass ≥ Forbs ≥ Fire Tolerant Shrubs ≥ Non-Native Species

This pathway occurs when disturbances such as fire, insects, prolonged drought, pathogens, and/or overgrazing reduce the dominant shrub overstory. Fire and overgrazing are the most common of these disturbances.

Pathway 2.4a
Community 2.4 to 2.1

Perennial Cool-season Grass ≥ Forbs ≥ Fire Tolerant Shrubs ≥ Non-Native Species

Bonneville big sagebrush ≥ Perennial Cool Season Grass ≥ Forbs ≥ Other Native Shrubs ≥ Non-Native Species

This pathway occurs over time and without a catastrophic event. This pathway may be dependent on a specific chain of climatic events.

State 3
Utah Juniper/Invasive Annual State

The plant community moves to the Utah Juniper/Invasive Annual State (3) when there is a lack of fire, and a source of Utah juniper and pinyon seed. The dominate aspect of the plant community is Utah juniper and cheatgrass brome. This State can persist for a long time until an extreme event such as a fire or other management treatment such as overgrazing occurs.

Characteristics and indicators. This state will have a noticeable presence of Utah juniper.

Community 3.1
Utah Juniper ≥ Bonneville Big Sagebrush ≥ Native Perennials ≥ Invasive Annuals

This community has a strong overstory of Utah juniper and singleleaf pinyon, the understory is similar to community 2.1. This community has approximately 20 to 35 percent bare ground and surface rock fragments. Fire may bring this community back toward the Current Potential State (2).

Community 3.2
Utah Juniper ≥ Invasive Annuals

This community is present when 99 percent of the native plants have been removed from the plant community and only pinyon and juniper with a sparse understory of invasive annuals remain on the site. This community has approximately 35 to 85 percent bare ground and surface rock fragments. Few native plants such as Sandberg bluegrass, may occur in this community phase.

Pathway 3.1a
Community 3.1 to 3.2

This pathway occurs due to overgrazing, with or without drought, over a prolonged period of time.

Pathway 3.2a
Community 3.2 to 3.1

This pathway occurs when disturbances such as fire, insects, prolonged drought, and/or pathogens, reduce the dominant shrub overstory. Fire is the most effective of these disturbances.

State 4
Bonneville Big Sagebrush / Broom Snakeweed State ≥ Invasive Annuals

The Bonneville Big Sagebrush/Broom Snakeweed State (4) occurs when the site is overgrazed for a prolonged period of time. Drought, fire, mechanical disturbance, and other like disturbances will speed up the process.

Community 4.1
Bonneville Big Sagebrush ≥ Broom Snakeweed ≥ Sandberg Bluegrass ≥ Invasive Annuals

This community has approximately 35 percent Bonneville big sagebrush, 35 percent broom snakeweed, and 15 percent grass and forb. When the air dry production is considered it would approximate 35 percent Bonneville big sagebrush, 55 percent broom snakeweed, and 10 percent grasses and forbs. Most of the grasses and forbs are non-native annuals. This community has approximately 20 to 35 percent bare ground and surface rock fragments.

Community 4.2
Broom snakeweed ≥ Invasive Annuals ≥ Sandberg Bluegrass

This plant community has lost the Bonneville big sagebrush and the invasive annuals have reduced the areas of Sandberg bluegrass. The broom snakeweed controls about 75 percent of the annual production. This community has approximately 35 to 40 percent bare ground and surface rock fragments.

Pathway 4.1a
Community 4.1 to 4.2

This pathway occurs when disturbances such as fire, insects, prolonged drought, and/or pathogens, reduce the dominant shrub overstory. Fire is the most effective of these disturbances.

Pathway 4.2a
Community 4.2 to 4.1

This pathway occurs over time, when management practices such as grazing are used, as well as the introduction of native or perennial plant species.

State 5
Yellow Rabbitbrush / Invasive Annuals State

The Yellow Rabbitbrush/Invasive Annuals State (5) plant community occurs when it has been overgrazed and/or in a drought condition; and then burned (wild or controlled) and not seeded. The dominant aspect of the plant community is cheatgrass brome, yellow rabbitbrush, with a very small amount of Bonneville big sagebrush. The community will usually be made up of 70 percent cheatgrass brome, 10 percent forbs, and 20 percent yellow rabbitbrush with minor components of other shrubs.

Community 5.1
Yellow Rabbitbrush ≥ Invasive Annuals

This plant community consists of approximately 40 percent yellow rabbitbrush, 45 percent invasive annuals, and 10 percent native perennials with a small component of other species. This community has approximately 20 to 35 percent bare ground and surface rock fragments.

Community 5.2
Invasive Annuals

This plant community consists of approximately 85 percent invasive annuals (mostly cheatgrass brome and Japanese brome [also known as field brome]), and 10 percent native perennials with a small component of other species. This community has approximately 20 to 40 percent bare ground and surface rock fragments.

Pathway 5.1a
Community 5.1 to 5.2

This pathway occurs with increased fire frequency and intensity without follow-up management. Overgrazing can move this change along faster. In the Yellow Rabbitbrush/Invasive Annuals State (5) the fire interval frequency will remain at 3 to 5 years. This condition is self-sustaining and the site will keep deteriorating until the site potential is lost.

Pathway 5.2a
Community 5.2 to 5.1

This pathway occurs over time, when management practices such as grazing are used, as well as the introduction of native or perennial plant species.

State 6
Seeded Range State

The Seeded Range State (6) exists when the site is cultivated and/or burned, and then planted to introduced and/or native grasses and forbs.

Characteristics and indicators. This state consists of predominantly non-native seeded range species.

Community 6.1
Introduced Perennial Plants

The plant community consists of introduced and/or native grasses and forbs. Productivity levels may compare to the productivity levels in the Current Potential State (2).

Community 6.2
Native Shrubs = Introduced Perennial Plants

This plant community develops when weather conditions create the kind of episodic situation that allows Bonneville big sagebrush to move back onto the site.

Pathway 6.1a
Community 6.1 to 6.2

This pathway occurs over time, and without a catastrophic event. This may be dependent on a specific chain of climatic events.

Pathway 6.2a
Community 6.2 to 6.1

This pathway occurs over time, and when management practices such as grazing are used, as well as other disturbances where human intervention takes place to move the community back.

Transition T1a
State 1 to 2

This transition occurs when there is an introduction of non-native species into the ecosystem.

Transition T1b
State 1 to 4

This pathway occurs when disturbances such as fire, insects, prolonged drought, pathogens, and/or overgrazing reduce the dominant shrub overstory. Fire and overgrazing are the most common of these disturbances.

Transition T2a
State 2 to 3

This transition takes place when the sagebrush canopy has increased so it destroys the perennial grass and forb understory and the fire interval frequency increases to 60 to 90 years from an average of 20 to 40 years. Disturbances such as prolonged drought, overgrazing, and extreme lengthening of the fire interval frequency contribute to the introduction of Utah juniper on to the site.

Transition T2b
State 2 to 4

This transition occurs due to prolonged drought and/or prolonged overgrazing.

Transition T2c
State 2 to 5

This transition occurs due to continued overgrazing and an increase of fire frequency over a prolonged period of time.

Transition T3b
State 3 to 5

This transition occurs due to continued overgrazing and an increase of fire frequency over a prolonged period of time.

Transition T3a
State 3 to 6

This transition occurs due to disturbances caused by humans such as mechanical treatment and seeding, and/or chemical treatment and seeding.

Transition T4a
State 4 to 6

This transition occurs due to disturbances caused by humans such as mechanical treatment and seeding, and/or chemical treatment and seeding.

Transition T5a
State 5 to 6

This transition occurs due to disturbances caused by humans such as mechanical treatment and seeding, and/or chemical treatment and seeding.

Restoration pathway R6a
State 6 to 2

This restoration pathway takes approximately 25 to 50 years. Time, along with proper management that favors the native plants may return them to the site. The time frame depends on management and on the precipitation amounts. If the site is at the 15- to 16-inch precipitation zone it will respond quicker than at the 14-inch zone. Proper grazing management along with rest periods for the site may reduce the time it takes the restoration process.

Transition T6a
State 6 to 3

This transition takes place when the sagebrush canopy is so heavy that it destroys the perennial grass and forb understory and the fire interval frequency increases to 60 to 90 years from an average of 20 to 40 years. Prolonged drought, overgrazing, and extreme lengthening of the fire interval frequency are disturbances that contribute to the introduction of Utah juniper to the site.