Subalpine Windswept Shallow Meadow 25-30" PZ Cryic Northern Rocky Mountain Front

Description

1.0 Historic Reference State with No Weedy Species Present

Characteristics and indicators

Kinnikinnick (Arctostaphylos uva-ursi)(common juniper(Juniperus communis)-shrubby cinquefoil(dasiphora fruticosa)-rosa species)/rough fescue(Festuca campestris)pinegrass(Calamagrostis rubescens)/yarrow(Achillea millefolia)-rosy pussytoes(antennaria rosea)-Ross’s sedge (Carex rossii)-northern bedstraw(Galium boreale)-sulpher-flower buckwheat(eriogonum umbellatum).

The 43B Subalpine Windswept Shallow Meadow ecological site is dominated by the low-growing shrub kinnikinnick (Arctostaphylos uva-ursi), and rough and Idaho fescues. Kinnikinnick is shade-intolerant and grows best in open areas, forming a compact and intricate mat (Severson, 1974). In the forest, it is found in more open canopies and has long, thin trailing stems. Kinnikinnick is a stoloniferous, mat-forming, woody subshrub. It has a compact clonal pattern. The main stems are prostrate with secondary branching stems ascending and erect to 15 cm. Regeneration primarily is asexual, with the second-year stolons producing adventitious feeding roots at the nodes. After seven or eight years, small nodules may appear at intervals along the buried stems. These are not nitrogen-fixing nodules. The berrylike drupes are dispersed by animals. Seedling growth is slow for the first 3 years, then increases. Roots can extend to a depth of 70 to 90 cm. Kinnikinnick browse is of moderate importance to bighorn sheep, mountain goat, black-tailed deer, white-tailed deer, and Rocky Mountain mule deer (Kufeld, 1973). Moose browse kinnikinnick on snow-free areas near trees on south and west aspects in early spring (Stevens, 1970). Black and grizzly bears eat the fruits in the autumn and especially in the early spring (Mace, 1986). Kinnikinnick is unpalatable to domestic livestock. It is easily killed by scraping or fire, but is able to regenerate from surviving parts or seed. It is a sprouting species that is best suited to short fire cycles with low fuel buildup and low fire intensities. Kinnikinnick is moderately resistant to trampling, with both low short- and long-term resilience (Zimmerman, 1984). It is a host to yellow witches’ broom, which affects spruce species (Watson, 1980).

Rough fescue is a native, cool-season, perennial bunchgrass that produces thick mats of persistent sheath and stem bases: and culms grow to 107cm (3.5 feet) and leaf tufts to 40 cm (16 inches) in height (Cronquist, 1977). It has extensive fibrous roots to a depth of 122 cm (4 feet), 73 percent of which are concentrated in the top 15 cm (6 inches) of soil (Coupland, 1953). It regenerates from seed, tillers and sometimes rhizomes (Pavlick, 1984). It is well adapted to a short growing season by initiating growth following snowmelt and completes growth before the onset of summer drought. It is very productive and highly palatable to livestock and wildlife. It is used by bighorn sheep, mule deer, elk and bison. It is resistant to moderate grazing but heavy grazing can result in severely decreased root depth and biomass (Aiken, 1990). Grazing can cause a general decline in rough fescue coverage and is one of the first species to decline with common increasers with grazing being: Idaho fescue, needlegrass species, prairie Junegrass and Parry’s oatgrass. It is well adapted to periodic burning and resistant to light fire by their dense, tufted habit. It sprouts from surviving residual plants and colonizes from off-site wind-dispersed seed. Fire may top-kill plants, but cover and production is usually attained in 2-3 years post-fire. Severe damage can occur by hot, mid-summer wildfires (Wright, 1982). Rough fescue and elk sedge are considered very resistant to human trampling due to its tough core of the tuft, according to D. Cole of the USFS in his study of recreational human trampling effects on habitat types in western Montana. The majority of the loss of cover, a reduction of 50 percent, occurred in the first 400 passes. Thereafter, cover loss was stabilized from 400 to 800 passes. The community of rough fescue-timber oatgrass is considered very resistant to both light and heavy trampling (Cole, 1987).

Asebrook (2010) found that in 31 plots sampled of this type of dwarf-shrubland (kinnikinnick-rough fescue) was in very good to excellent condition with very low cover of exotic species. Exotic grass cover averages one to three percent and exotic forb cover of one percent. There was little tree invasion no more than one percent cover within the plots, but half did have tree invasion at least at the edges. Rhizomatous shrubs have invaded 23 percent of the plots observed. Lack of fire was attributed to allowing woody plants to become established at the edges. Current trespass and grazing by livestock was noted as having an impact on this site although it is periodic with low overall impact.

Submodel

Description

2.0 Current Potential State With Very Low Cover of Weedy Species

Characteristics and indicators

Current Reference State with weedy species present at a very low canopy cover value.
kinnikinnick(Arctostaphylos uva-ursi)-common juniper(Juniperus communis)-shrubby cinquefoil(dasiphora fruticosa)-rose(rosa species)/rough fescue(Festuca campestris)-pinegrass(Calamagrostis rubescens)/yarrow(Achillea millefolia)-rosy pussytoes(antennaria rosea)-Ross’s sedge (Carex rossii)-northern bedstraw(Galium boreale)-sulphur-flower buckwheat(eriogonum umbellatum).

Submodel

Description

Invaded State

This state represents the community with significant increase in weedy species and concomitant decrease in native grass species.

Submodel