Ecological dynamics
Ecological Dynamics of the Site
This grand fir site is on the moister end of the grand fir series and can have many tree species occurring depending on disturbance and seed source. Douglas-fir is the main seral species and will occur in mature stands with grand fir with fire exclusion. Engelmann spruce can also be present in fire excluded mature stands. With stand replacing or mixed severity disturbance Douglas-fir, western larch, ponderosa pine, western white pine, and lodgepole pine can occur in mixed stands. Quaking aspen, paper birch, and black cottonwood can be present in early to mid-seral stands.
Key understory species include Douglas maple, ninebark, oceanspray, serviceberry, snowberry, twinflower, honeysuckle, Oregon grape, rose, thimbleberry, pachistima, Scouler willow, spirea, pinegrass, brides bonnet, pathfinder, sweetroot, starry solomonplume, western princes pine, and white hawkweed.
Root rot and beetle kill will occur in the mature grand fir – Douglas fir stands. Western white pine once would have been more prevalent in the seral to mature stands, however, blister rust has made it a minor component of current stands. Low intensity frequent fires will favor more open western larch, Douglas-fir, and ponderosa pine stands. Mixed severity fires will create a mosaic of mixed stands of all tree species. Severe fires may create ceanothus brush fields with tree regeneration slow to reclaim the site.
State 1
Reference
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)
Dominant plant species
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Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca), tree
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western larch (Larix occidentalis), tree
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grand fir (Abies grandis), tree
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Rocky Mountain maple (Acer glabrum), shrub
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pipsissewa (Chimaphila umbellata), shrub
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Saskatoon serviceberry (Amelanchier alnifolia), shrub
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hollyleaved barberry (Mahonia aquifolium), shrub
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common snowberry (Symphoricarpos albus), shrub
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longtube twinflower (Linnaea borealis ssp. longiflora), shrub
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Oregon boxleaf (Paxistima myrsinites), shrub
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mallow ninebark (Physocarpus malvaceus), shrub
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oceanspray (Holodiscus discolor), shrub
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white spirea (Spiraea betulifolia), shrub
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thinleaf huckleberry (Vaccinium membranaceum), shrub
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Scouler's willow (Salix scouleriana), shrub
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common lomatium (Lomatium utriculatum), shrub
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Greene's mountain ash (Sorbus scopulina), shrub
Community 1.1
Reference Phase
Mixed severity fires create a mosaic of mixed stands of seral species mixed with grand fir. Regeneration could include all the species depending on exposed mineral soil and seed source. Western larch, ponderosa pine, Douglas-fir, and lodgepole pine would be first to regenerate. Western white pine will also be present, but not as prevalent as before due to blister rust. Grand fir will be present, however will come underneath the seral species in time. Quaking aspen can establish after these mixed fires and be a component in the stand. Age: 80+ years
Dominant plant species
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grand fir (Abies grandis), tree
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western larch (Larix occidentalis), tree
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Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca), tree
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hollyleaved barberry (Mahonia aquifolium), shrub
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common snowberry (Symphoricarpos albus), shrub
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longtube twinflower (Linnaea borealis ssp. longiflora), shrub
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Oregon boxleaf (Paxistima myrsinites), shrub
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mallow ninebark (Physocarpus malvaceus), shrub
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oceanspray (Holodiscus discolor), shrub
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white spirea (Spiraea betulifolia), shrub
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thinleaf huckleberry (Vaccinium membranaceum), shrub
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Scouler's willow (Salix scouleriana), shrub
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common lomatium (Lomatium utriculatum), shrub
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Greene's mountain ash (Sorbus scopulina), shrub
Community 1.2
Stand Initiation
Herbs and shrubs reestablish on site. Ceanothus species can dominate if fire caused soil degradation. Tree regeneration can be mixed or dominated by western larch and lodgepole pine. Ponderosa pine and Douglas-fir can also be present. White pine was a major factor in regeneration before the blister rust reduced its significance. Age: 0 – 20+ years
Community 1.3
Stem Exclusion
Dense stands of mixed seral species or dominated be larch or lodgepole pine. Douglas-fir, ponderosa pine, and western white pine, can be in the stand. Age: 100+ years
Community 1.4
Frequent Low Intensity Fires
Frequent low severity fires create an open stand of mature Douglas-fir, Western larch, ponderosa pine, and lodgepole pine.
This condition is perpetuated with continual ground fires. Age: 30 – 70 years
Pathway 1.1A
Community 1.1 to 1.2
Stand replacing fire back to the herbs and shrub stage. Regeneration dependent on seed source and brush competition.
Pathway 1.2A
Community 1.2 to 1.3
Tree regeneration grows into dense pole stand. Species can be mixed or dominated by larch or lodgepole.
Pathway 1.3B
Community 1.3 to 1.1
Mixed severity fires create patchy mosaic as in reference plant community phase
Pathway 1.3A
Community 1.3 to 1.2
Stand replacing fire.
Pathway 1.3C
Community 1.3 to 1.4
Frequent low severity fires create open pole stands.
Pathway 1.4B
Community 1.4 to 1.1
Fire interval lengthens, and tree regeneration becomes established. Mixed severity fires create patchy mosaic of seral species and grand fir.
State 2
Fire Exclusion
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.
Community 2.1
Fire Exclusion
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.
State 3
Shrubfields
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.
Community 3.1
Shrubfields
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.
Transition T1A
State 1 to 2
100+ years of fire exclusion will move the site to a mature grand fir – Douglas-fir site.
Transition T1B
State 1 to 3
Successive severe burns kill regeneration and maintaining sprouting shrubs dominance.
Restoration pathway R2A
State 2 to 1
Overstory management with ground burning will favor seral species.
Restoration pathway R3A
State 3 to 1
Careful site selection and fire control allow tree regeneration to establish
