Loamy 12-16 PZ

Description

State 1, Phase A, Reference Plant Community Phase. This plant community is dominated by mountain big sagebrush with bluebunch wheatgrass and Idaho fescue in the understory. Subdominant species include streambank wheatgrass, Letterman’s needlegrass, Sandberg bluegrass, and arrowleaf balsamroot. There is a wide variety of other grasses, forbs and shrubs in the plant community that occur in minor amounts. Natural fire frequency is 20-50 years.

State 1, Phase B. This plant community is dominated in the overstory by mountain big sagebrush with some Utah juniper seedlings and saplings invading. Sandberg bluegrass, streambank wheatgrass, slender wheatgrass, and bottlebrush squirreltail have increased. Bluebunch wheatgrass and Idaho fescue are still significant in the plant community but with reduced amounts and in low vigor. A wide variety of other grasses, forbs and shrubs still may occur but in very small amounts and may be in low vigor. A Utah juniper seed source is present in nearby sites. Some annuals have invaded the community. This state has developed due to fire frequency being much longer than normal and improper grazing management.

State 1, Phase C. This plant community is dominated by bluebunch wheatgrass. Sandberg bluegrass, bottlebrush squirreltail, and streambank wheatgrass with other perennial grasses and forbs are subdominant. Idaho fescue, Letterman’s and Columbia needlegrasses have decreased and may have died out due to fire. Most shrubs are absent from the site due to recent fire, except some rabbitbrush, horsebrush, and mountain snowberry may be present due to root sprouting. Some annuals may have invaded the site. The community is a result of recent wildfire or prescribed burning.

State 1, Phase D. This plant community is dominated by mountain big sagebrush in the overstory with significantly reduced amounts of Idaho fescue and bluebunch wheatgrass and in reduced vigor. Sandberg bluegrass, bottlebrush squirreltail, slender wheatgrass, and streambank wheatgrass have increased. Other bunchgrasses have been reduced and are in low vigor. There is no Utah juniper seed source in the proximity. Some annuals may have invaded the site. This plant community has developed due to improper grazing management and no fire.

Submodel

Description

State 2. This plant community is dominated by Sandberg bluegrass and annuals in the understory. There may be a variety of invasive forbs and some noxious species may have invaded the site. Some soil loss has occurred. The community has developed due to frequent fire and continued improper grazing management. This site has crossed the threshold. It is economically impractical to return this state to State 1 with accelerated practices.

Submodel

Description

State 3. This plant community is dominated by Utah juniper with Sandberg bluegrass and annuals in the understory. There are few shrubs present due to competition from junipers. Some deep-rooted perennials may be present under the junipers. Generally, shrub cover is below 12-13%, bare ground is above 27-28%, juniper cover is greater than 20%, and infiltration is less than 6 cm/hr when the plant community crosses the threshold. Some soil loss has occurred. This plant community has developed due to continued improper grazing management and lack of fire. This site has crossed the threshold. It is economically impractical to return this community to State 1 with accelerated practices.

Submodel

Description

State 4. This plant community may be seeded to introduced species or a mixture of native species to mimic State 1

Submodel

Description

Unknown new site. This plant community has gone over the threshold to a new site. Site potential has been reduced. Significant soil loss has occurred. Infiltration has been reduced and run-off has become more rapid. This state has developed due to continued improper grazing management and no fire or frequent fires from State 2 or the continued absence of fire from State 3 where a juniper seed source is present. This unknown new site can also be reached from State 3 with further dominance of the site by juniper. It is economically impractical to return this community to State 1 with accelerated practices.

Submodel