Vitrandic Hills and Mountains 33-38" PZ Cool Frigid

Description

This state is dependent on fire severity and time intervals of fire. Many tree species will grow on this moist grand fir site. Douglas-fir, western larch, western white pine, ponderosa pine, lodgepole pine, Engelman spruce, and grand fir are the major conifer species. Quaking aspen, paper birch and black cottonwood can also be present. This ecological site has good forest productivity for Douglas-fir, western larch, and ponderosa pine. In N. Idaho western white pine would have good productivity. Low severity frequent fires create open stands of larch, Douglas-fir, ponderosa pine, and lodgepole pine. Mixed severity fires create a mosaic of a variety of tree species and different age groups. Tree regeneration after stand replacing fires will be variable depending on seed source. Western larch, western white pine, Douglas-fir, ponderosa pine, and lodgepole pine will be the main species. Western white pine used to play a major role in regeneration, however, the white pine blister rust has reduced its occurrence in regenerating stands. Western larch, Douglas-fir, and ponderosa pine are more prevalent. Reoccurring severe fires in the stand initiation phase can create shrub fields of ceanothus spp., and a variety of other shrubs. Fire exclusion for long periods allow the forest to move to an all aged grand fir, Douglas-fir, and Engelmann spruce stand. Root rot and defoliating insects then becomes are concern in the grand fir and Douglas-fir causing much downed wood and fuel loads.

Characteristics and indicators

Plant List
Overstory Trees

Douglas-fir (Pseudotsuga menziesii )
Western Larch (Larix occidentalis)
Grand fir (Abies grandis)

Understory trees

Grand fir (Abies grandis)

Understory Shrubs

Douglas maple (Acer glabrum Douglasii)
Western prince’s pine (Chimaphila umbellata)
Serviceberry (Almalachier alinofolia)
Oregon grape (Berberis aquifolium)
Snowberry (Symphoricarpos albus)
Twinflower (Linnaea borelalis)
Pachistima (Pachistima myrsinities)
Ninebark (Physocarpus malvaceus)
Oceanspray (Holodiscus discolor)
Shiny leaf spirea (Spirea betulifolia)
Big huckleberry (Vaccinium membranaceum) (cooler sites)
Scouler willow (Salix scouleriana)
Utah honeysuckle (Lonicera utahensis)
Mountain ash (Sorbus scopulina) (cooler sites)

Understory Herbs

Pathfinder (Adenocaulon bicolor)
Sweetroot (Osmorihiza chilensis)
Starry solomonplume (Smilacina stellata)
Queencup beadlily (Clintonia uniflora)
White hawkweed (Hieracium albiflorum)
Western meadowrue (Thalictrum occidentale)

Submodel

Description

An all aged stand of grand fir and Douglas-fir with Engelmann spruce mixed in occurs when fire interval is extended 100 years or more. Grand fir will dominate the regeneration in the understory. In the drier areas of this site root rot and defoliating insects can be a problem. Snags and downed wood will be common in these areas. This state will be susceptible to stand replacing fires.

Submodel

Description

Successive severe ground fires create shrub fields for long time periods. Ceanothus species, ninebark, oceanspray, snowberry, spirea, Douglas maple, Scouler willow and serviceberry will dominate preventing tree regeneration.

Submodel