Environment, Prehistory & Archaeology of Mount Rainier National Park, Washington
Greg C. Burtchard
Chapter 2:
ENVIRONMENT AND LAND-USE ON MOUNT RAINIER & IN THE SOUTHERN WASHINGTON CASCADES
(continued)
ENVIRONMENTAL ZONES, RESOURCES AND HUMAN
LAND-USE PATTERNS
Ecological Maturity, Resource Abundance and the Northwest Maritime Forest
Due to similar latitude and position relative to Pacific westerlies, the Cascades share general climate and environmental patterns. The Coast Range, Puget Trough, Olympics and Cascades are exposed to a relatively mild, seasonally wet maritime climate along the foothills and western slopes. As Pacific air masses flow over the high Cascades and down the eastern slope, adiabatic warming increases moisture holding capacity and induces the drier climatic regimes characteristic of the Columbia Plateau.
In direct response to moist, relatively stable climatic conditions, the greater northwest maritime region tends toward states of high ecological maturity; that is, toward generally dense, stable forest cover. While not alluding to maturity directly, Heusser (1983:241), citing Waring and Franklin (1979), emphasizes this effect for the Pacific Northwest.
The climatic regimen of winter storms (with protracted periods of moisture and cloudiness, summers with relatively short intervals of soil-water loss, and moderate temperatures over much of the year) is very favorable for tree growth and accounts for the dense coniferous forests of the region. The forests with massive trees of great longevity are unrivaled among temperate forest regions of the world.
In a natural state, dense hemlock and fir forests carpet much the region from the Puget Trough, to the eastern slopes of the southern Washington Cascades. Though specific plant communities vary in response to micro-climate and sediment differences, and especially to forest perturbation (lahars, winds and fires), the general tendency is toward mature, wet forest conditions up to about 5,500 ft above sea level near Mount Rainier. I refer to this mature forest pattern as the Northwest Maritime Forest (see Burtchard and Keeler 1991:17-32). At higher elevations, Pacific Maritime Forests give way to subalpine parkland, alpine tundra, and, on the highest peaks, to glacial snowpack and rubble. On the eastern slope, maritime fir forests grade to more xeric interior pine stands and ultimately to the shrub steppe of the Columbia Plateau.
Forest maturity patterns are important because they are linked to the distribution and abundance of edible plant and animal resources in the maritime Northwest. In a mature or late successional state, Northwest Maritime Forests are difficult places to live. Food sources are limited by the tendency of uniform, high maturity forests to lock up most of their energy and nutrient budget in standing biomass (principally cellulose). A relatively small percentage goes to edible foliage or reproductive parts (see Pianka 1974:89-90; Odum 1971:385; and Whittacker 1975:137). [6] Edible biomass is highest not in the forest proper, but in lower maturity subalpine parkland and alpine tundra associations above the forest line, or at other places where forest cover has been reduced temporarily by fire, landslides, lahars or other sources of disturbance. Consequently, in the Cascades and on Mount Rainier, the most productive habitats over the long term are alpine grasslands, patchy subalpine forest, open wet meadow associations, and patchy interior pine forests (not represented in the Park). Disturbance related low maturity areas are productive as well, but tend to be temporary; closing as the maritime forest regenerates. Laced through this general pattern are salmon bearing rivers and tributary streams locally capable of sustaining intensive human use given sufficient need and labor to meet extraction and storage demands.
In short, high maturity tendencies of the Pacific Maritime Forest tend to suppress food resources necessary to sustain prehistoric populations. In order to maximize access to seasonally available game and edible plants, successful groups were obliged to focus their activities toward lower maturity or earlier succession zones regardless of cultural affiliation or idiosyncratic preferences (i.e., toward open to patchy habitats however they were created and maintained). Accordingly, the key to understanding patterned prehistoric use of Mount Rainier, lies in large measure in our ability to understand the distribution of low to higher maturity habitats within the general forest regime. The following sections address this issue.
Mount Rainier Environmental Zones and Human
Use
Several taxonomic systems have been devised to characterize forest or plant associations in the Pacific Northwest. The earliest widely applied system characterized forest constituents in terms of south to north latitudinal patterns for the North American continent; keyed to roughly comparable elevation zones on Mount Rainier. In their manuals on Mount Rainier flora and fauna, Brockman (1947) and Taylor and Shaw (1927) used this system to distinguish Humid Transition and Canadian, Hudsonian subalpine forest, and Arctic-Alpine snowfield and tundra zones for the Park. Even though the system oversimplifies local variability, it nonetheless provided useful distinctions between modal plant and animal communities that result from elevationally induced variation in growing season and snowpack.
Perhaps the best known environmental taxonomy for Oregon and Washington was developed by Franklin and Dyrness (1973). Because of its descriptive rigor and applicability to varied settings, this work has become the de facto standard for archaeologically-related environmental descriptions in the Northwest. Franklin and Dyrness' system improves on earlier continental zones by emphasizing combined effects of physiography, climate, and sediment structure to map climax plant associations. For the southern Washington Cascades and Mount Rainier, climax forest zones include 1) Tsuga heterophyla (western hemlock) forest at lowest elevations; grading to 2) Abies amabilis (Pacific silver fir) associations on intermediate slopes; and 3) Tsuga mertensiana (mountain hemlock) forests above 1,250 m (4,100 ft). Mountain hemlock associations become increasingly patchy toward timberline until dominated more by subalpine meadow grasses, sedges and composite flowers than by trees. Fully alpine tundra grasslands are situated between timberline and permanent snowfields above circa 8,000 ft. As will be seen, the system used in the present report builds on Franklin and Dyrness' scheme by grouping Tsuga heterophyla through lower Tsuga mertensiana forests into the single Northwest Maritime Forest class that emphasizes their shared tendency toward high maturity.
In Vegetational History of the Northwestern United States, Heusser (1983:243) models forest associations from the Puget Trough to the crest of the southern Washington Cascades near Mount Rainier. He emulates Franklin and Dyrness' distinctions but couches them in terms more easily recognized as forest/landscape types. Heusser's model (Figure 2.4) is included below because of its similarity to environmental distinctions used here, and because it simulates a mountain profile, drawing attention to the effects of decreasing temperature on key vegetation constituents. Modifications are indicated in brackets.
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| Figure 2.4 Vegetation Zones: Puget Trough - S. Washington Cascades (after Heusser 1983) |
The most thorough consideration of forest association patterns for the immediate project area is Franklin et al.'s (1988) The Forest Communities of Mount Rainier National Park. The authors identify a mosaic of climax associations keyed to four Park quadrants and associated river systems. Elevation and moisture related variability in floral composition and understory dominants are used to provide a more realistic picture of plant associations in various parts of the Park. Importantly, the authors move beyond the three-part high maturity/climax plant association system to consider maturity reducing impacts of major fires, avalanches and lahars. Figure 2.5 is a simplified mosaic of Mount Rainier National Park habitat types as affected by temperature (i.e., elevation) and precipitation (primarily windward versus leeward position on the mountain). It provides a notion of the complexity that underlies simpler forest constructions; and draws attention to an important food resource –Vaccinium – as an understory constituent and seral dominant when Abies amabilis forests are disturbed by fire (see the ABAM/VAAL association in Figure 2.5). Interested readers should refer the complete volume (see also Moir 1989) for detailed consideration of Mount Rainier floral associations.
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Figure 2.5 Generalized Distribution of Mount Rainier Habitat
Types (after Franklin et al. 1988:34)
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Useful as it is for developing a thorough understanding of Mount Rainier forest ecology, the Franklin et al. (1988) study is unnecessarily complex for present purposes. The most salient issues are those that address relative forest maturity, distribution and abundance of food resources, and factors that alter the forest's maturity/resource balance. It already has been emphasized that in general 1) Northwest Maritime Forests tend toward high maturity; 2) variety and abundance of game and edible plant resources tend to vary inversely with maturity; 3) maturity decreases in a more or less regular, predictable fashion with elevation, maximizing food resource abundance in subalpine and lower alpine habitats; and 4) maturity is reduced in an irregular, less predictable fashion in response to large fires and other forest disturbing phenomena. To accommodate these considerations, the system outlined below isolates five environmental zones that includes three major plant associations keyed to variable maturity and resource distribution patterns; a low elevation river valley subzone; and high elevation glacier/ permanent snowfield category. The maturity reducing effect of fire on forest habitats is discussed as well.
Table 2.2 correlates the present taxonomy with those outlined above. Franklin et al.'s (1988:64-75) modal forest ecosystem structure is used to represent their more elaborate mosaic system. Please note that elevation breaks between all zones are approximate. Boundaries typically are more gradual than shown and vary locally with precipitation, exposure, sediment structure and so on. Alternating gray and white bands indicates zonal concordance to the system used here.
Table 2.2 Mount Rainier Environmental Zonation Systems
Northwest Maritime Forest
Low to Mid-Elevation Forest
Except for high elevation landscapes, Northwest Maritime Forest
associations blanket most of the region from the Puget Trough to the
eastern flank of the southern Washington Cascades. Western hemlock
(Tsuga heterophylla) and western red cedar (Thuja plicata)
are consistent low elevation dominants. Though probably a seral
constituent, Douglas fir (Pseudotsuga menziesii) is presently the
most common tree associated with low to moderate elevation forests.
Salal (Gaultheria shallon) is a frequent understory species
(Franklin and Dyrness 1973:89). Prairies with patchy stands of Douglas
fir, oak (Quercus garryana), and shrubs are common in the Puget
Trough south of Puget Sound. Prior to modern development, these lower
maturity prairies probably were maintained by low summer precipitation
coupled with gravelly glacial outwash soils, and by periodic burning by
Indian groups (Franklin and Dyrness 1973:89; cf., Taylor and Shaw
1927:9). The latter case illustrates the capability of humans to
maintain and/or increase the productive capacity of their environment by
repressing forest succession (i.e., by lowering ecosystem maturity).
Low elevation western hemlock forests grade into mid-elevation associations dominated by Pacific silver fir (Abies amabilis) at about 3,000 to 3,500 ft in the southern Washington Cascades. Silver fir associations are the Park's primary forest type up to circa 4,000 to 4,500 ft. This is the heart of Franklin et al.'s (1988) silver fir/Alaska huckleberry (ABAM/VAAL) and other Abies amabilis associations shown on Figure 2.5. Though dominated by silver fir, forest constituents vary widely with exposure and age. Other common tree species include western hemlock, noble fir (abies procera), Douglas fir, western red cedar (Thuja plicata–wet sides), and western white pine (Pinus monticola). Aside from Vaccinium, locally dominant understory constituents include Oregon grape (Berberis nervosa) and salal (Gaultheria shallon) on the dry side; and devilsclub (Oplopanax horridum) and skunk cabbage (Lysichitum americanum) in wetter areas.
Upper Elevation Forest
Above 4,500 ft, mountain hemlock (Tsuga mertensiana),
subalpine fir (Abies lasiocarpa), Alaska yellow cedar
(Chamaecyparis nootkatensis), and western white pine (Pinus
monticola) silver fir forests become increasingly prevalent. On
wetter northwest, west and southeastern exposures, Pacific silver fir
tends to maintain its upper story dominance. Primary understory
co-dominants, however, shift from Alaska huckleberry toward dwarf
blackberry or dwarf bramble (Rubus lasiococcus), rustyleaf or
fool's huckleberry (Menziesia ferruginea) and rhododendron
(Rhododendron albiflorum) (Franklin et al. 1988:18). On the drier
northeastern, lee side of the mountain, mountain hemlock tends toward
upper story climax dominance, with beargrass (Xerophylum tenax)
dominating low ground cover. Due principally to vegetation repressing
effects of snowpack, closed maritime forests tend to reach only to about
5,200 ft on the wetter windward side of Mount Rainier, and to about
5,800 ft on the drier leeward side.
Forest Fauna
Taylor and Shaw (1927:11) list animals common to Mount Rainier's low
to mid elevation forests as
...Harris woodpecker, Gairdner woodpecker, northern red-breasted sapsucker, western pileated woodpecker, western flycatcher, Steller jay, Louisiana tanager, chestnut-backed chickadee, western golden-crowned kinglet, russet-backed thrush, and western bluebird. Mammals ...are the Trowbridge shrew, brown bat, bobcat, Cooper chipmunk, beaver, and snowshoe rabbit.
Of the larger animals, black-tailed deer are present in the forest were adequate browse is available, particularly at meadow fringes. However, both deer and elk (presumed to be present prehistorically) "during the summer months ...seek the higher levels of the park, where open spaces afford more sunlight and grass. They [deer] are especially fond of burns, where the thick vegetation provides an abundance of browse" (Taylor and Shaw 1927:118). Similar considerations apply to black bear. Marmots, goats and large birds (grouse and especially ptarmigan) tend to frequent higher elevation subalpine to alpine landscapes.
It is interesting and, from a prehistoric hunter's point of view, important to note that the most abundant mid-forest animal species are relatively small birds and mammals. Even though more economically useful larger game is present where browse permits, over the long run, most successful hunters would have followed their prey through the forest into more open subalpine and alpine settings at higher elevation.
The Huckleberry Issue
The single most noteworthy exception to the food resource poor
qualities of mature mid-elevation montane forests lies in their response
to major maturity-reducing disturbances. Franklin et al. (1988:150) note
that "Wildfire is, by far, the most important agent of forest
catastrophe at Mount Rainier National Park, followed by snow avalanches
and debris flows (lahars) (Hemstrom and Franklin 1982). Wildfires have
occurred on approximately 90 percent of the existing stands, avalanches
on 7 percent, and lahars on 2 percent." In cases of forest catastrophe,
huckleberries are a common early successional dominant. According to
Franklin et al. (1988) Vaccinium alaskaense is usually the most
abundant of the Mount Rainier huckleberries. [7] Four other mid-elevation varieties also are
common–black or big-leaf (V. membranaceum), blue or
oval-leaf (V. ovalifolium) and red (V. parvifolium)
huckleberry, and the small red grouseberry (V. scoparium).
Cascades or dwarf blue huckleberry (V. deliciosum) is more common
higher in subalpine settings. Western bog blueberry (V.
occidentale) and evergreen huckleberry (V. ovatum) are found
in low abundance, at low elevation (see Brockman 147:127-128). Abundance
of all species is increased by maturity reducing forest disturbances,
particularly fire, but diminishes as forest cover returns.
Because of its edible resource qualities and because deer, bears and birds are attracted to productive huckleberry grounds, Vaccinium may have been important to prehistoric foraging strategies. Indeed, during early historic times, huckleberry collection appears to have been the primary reason Indian groups came to Mount Rainier (Smith 1964:155). The most important varieties reported by Smith (1964:157-163) were oval-leaf (probably including Alaska) and big-leaf huckleberries in midelevation forests; and low growing dwarf huckleberries at higher elevation. Among other things, Smith goes on to discuss huckleberry drying techniques on mats and elevated racks; popular collecting grounds; the practice of setting fires to enhance huckleberry production; and packaging for downslope transport. At several points he notes the use of horse transport and coordination of berry collecting with hunting activities.
In my opinion, it is doubtful that the nutrient or caloric value of huckleberries was sufficient to overcome distance and bulk transport difficulties associated with mass harvest prior to introduction of the horse circa A.D. 1700. There is no doubt, however, that the resource was used extensively by small collecting parties emanating from various tribal groups on all sides of the mountain thereafter (see Smith 1964:149-179). Furthermore, given its history of repeated burns prior to modern fire suppression (Franklin et al. 1988:149-158), Mount Rainier could have supported substantial huckleberry habitat at ostensibly resource poor maritime forest elevations. For now, it must be recognized that burned and excessively drained mid-elevation habitats may have produced floral and faunal resources sufficient to attract significant human use in the past. The extent to which such use extended into the prehistoric past depends on the direct value of these berries as food plus the value of game co-occurring at midelevation berry grounds, compared to resources found at higher-elevation habitats. I suggest that despite presence of mid-elevation huckleberry habitat, the greater stability and overall higher productivity of subalpine habitats would consistently have attracted greater human use over longer stretches of time. If so, most of the Park's prehistoric archaeological record should be located in subalpine and alpine habitats with a lower frequency elsewhere.
Low Elevation Rivers and Floodplains
In a sense, rivers and associated floodplains are not a distinct environmental zone per se, but rather are more characteristic of maritime forest stands near sea level. This is generally true of the Park's lowest major floodplains–particularly the Carbon, Nisqually and Ohanapecosh Rivers in the Park's northwest, southwest and southeast corners. Brockman (1947:3) enthusiastically describes the Park's lower riverine forest in his Humid Transition Zone introduction as
...awe-inspiring in its quiet solitude; cathedral-like in its sombre, peaceful grandeur. So dense are the trees that their branches interlace overhead to form an evergreen canopy, and even on bright summer days a condition of semi-twilight exists on the forest floor. The great trunks rise from a tangled mass of shade-loving plants which, in places, approach tropical-like luxuriance. Other trees, leveled by age or the elements, sprawl upon the ground–some newly fallen, others festooned with moss, and some in the last stages of decomposition. The trails, carpeted by an accumulation of humus and forest litter, are soft and yielding to the tread.
Lahars and Floods
Inviting as such scenes may be, they are limited in scale by the
Park's overall high relief and physiographic instability. The subzone is
distinguished here less for its unique floral qualities in the mature
state described by Brockman, and more in recognition of Mount Rainier
river valleys' frequent exposure to maturity-reducing lahars and high
energy runoff, and because of presence and potential resource importance
of anadromous fish in some of the river systems.
Lahars represent the most spectacular destructive events to impact Mount Rainier's low elevation riverine environments. Effects of major Mount Rainier mud and debris flows such as the 5,000 year old Osceola and 500 year old Electron mud flows are well known. Lesser flows are destructive on a smaller scale, and are far more common. Because of its relief, heavy rainfall and geological youth, many of Mount Rainier's rivers and streams are subject to periodic disruption, particularly in upper to mid-level drainages (see Crandell and Mullineaux 1967, and Scott et al. 1995). Such events repress forest maturity, temporarily opening affected floodplains to more productive early succession plant and animal associations. Even in the absence of such spectacular events, high energy seasonal runoff on major rivers–such as that shown in Figure 2.6 on the Carbon River–are capable of altering river courses and transporting boulder-sized rock substantial distances, and in so doing, keep the forest fringe at bay.
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| Figure 2.6 Carbon River Floodplain. (Facing upstream from Northern Loop Trail crossing, September 4, 1995. Note that high energy flow is infringing on the west-bank forest margin.) |
Anadromous Fish
Because they improve forage by suppressing floodplain forest cover,
lahars and high energy floods promote a modest gain in exploitable
resource abundance. The most important riverine resources, however,
would not have been ungulates but salmon. Because of predictability and
high seasonal abundance, salmon has been an important resource for
regional populations since the mid-Holocene. The abundance and extent to
which anadromous fish penetrated into Mount Rainier National Park,
however, remains unclear. Despite repeated floods and debris flows, at
least limited salmon populations have been reported historically in
major river systems within Park boundaries (Samora pers. com. 1995). Her
sources allude to coho salmon (Oncorhynchus kisutch) in the
White, Carbon, Puyallup and Mowich Rivers; chinook (Oncorhynchus
tshawytscha) in both White River forks; and steelhead
(Oncorhynchus mykiss) in the Carbon, White, Puyallup and
Nisqually Rivers. Fulton (1968) reports fall chinook in the Cowlitz
River just south of Park Boundaries. He also reports steelhead spawning
areas in the Ohanapecosh well within the Park (Fulton 1970). Bull trout
(Salvelinus confluentus) and/or Dolly Varden (S. malma)
historically also were present in several of the Park's rivers (Samora
pers. com. 1995).
Combining information above with maps showing spawning areas (Fulton 1968, 1970) and major upstream impediments (Williams et al. 1975), it is possible to reconstruct roughly the extent to which spawning salmon physically could have entered Mount Rainier rivers. Figure 2.7 shows river systems and approximate upstream limits of unimpeded salmon migration. Rivers not highlighted have major cascades or falls that effectively preclude upstream migration well below Park boundaries. Please note that this projection should be considered a working model to be improved as more information is made available.
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| Figure 2.7 Potential Salmon-Bearing River Systems in Mount Rainier National Park |
Randall Schalk (pers. com. 1996) has studied Fulton and Williams map data, and offers these observations:
The White River appears to have no obstacles below a point slightly above the mouth of Deadwood Creek. The highest for present chinook usage appears to be Pinochle Creek and lower Huckleberry Creek north of the Park. Within Park boundaries, there are several White River tributary creeks that have salmon usage listed as unknown. Many say none. Coho usage is possible in some of the creeks that flow into lower Huckleberry Creek (a few miles north of the Park boundary) and possibly Silver Creek.
No modern salmon usage is shown in the Puyallup River within the Park. LeDout and Niessen Creeks show some coho usage but they are well downstream from the Park. There are three upper basin tributaries that penetrate the park apparently without natural obstructions (source Williams et al. 1975):
South Mowich R. (obstacle shown @ 3 mi into park)
North Fork Puyallup (obstacle shown at @ mi into Park)
South Fork Puyallup (blockage shown at @ mi into Park)
I have no data on steelhead usage of the Puyallup and Mowich Rivers although steelhead probably could get wherever chinook and coho go. Spring chinook probably migrated at least as far up as the cohos and probably beyond.
The main stream of the Nisqually presently is blocked above LaGrande by an impassable dam. How far salmon got up this drainage historically is less clear. No natural obstacles are shown on the river until just below Paradise. Goat and Tenas Creeks have no obstacles shown. Tahoma Creek has none on the lower two miles. No major obstacles are shown on Kautz Creek., though glacial silt is likely to have hindered spawning (source Williams et al. 1975).
Fulton's (1970) steelhead map for the upper Cowlitz shows steelhead presently use the lower portion of the Ohanapecosh River. Coho are shown as using the lower parts of Butter Creek and Lake Creek–two tributaries of the Cowlitz that enter below the Ohanapecosh. Fall chinook are shown in the Cowlitz still further below (Fulton 1968). I [Schalk] suspect that spring chinook probably would spawn at least as far upstream as coho and steelhead although Fulton doesn't provide detail at this fine scale.
It is important to recognize that, because of extensive habitat alteration, present fishery data are not good indicators of prehistoric presence or abundance. We have emphasized the position of upstream barriers to attempt to show maximum possible migration routes. Unfortunately, we cannot reconstruct specific upstream migration patterns or seasonality with precision. Even so, it unlikely that salmon were ever a major resource in the Park. Periodic floods and debris flows temporarily, but repeatedly, must have diminished anadromous fish habitat. Perhaps more important is the high energy, silt-laden character of the near mountain river systems. According to Schalk (pers. com. 1996):
The heavy loads of glacial silts further diminish the value of these kinds of streams as spawning habitat. Some salmon may have penetrated the Park in very limited numbers but salmon fishing this far upstream I believe would have always been poor at best. If people were harvesting any salmon at all within the park I suspect it was infrequent and incidental to other activities.
Floodplain Archaeology and Land-Use
Aside from maintaining
modest low maturity stream side ungulate habitat, the primary impacts of
river dynamics and lahars may have been most pronounced on the
archaeological record itself. Destructive impact of larger lahars is
obvious. Though less destructive, smaller mud and debris flows, and
annual hydrological activity also have erased the stream side
archaeological record from time to time. Accordingly, it is unlikely
that low elevation floodplains preserve a substantial record of the more
distant prehistoric past, at least for larger, more geologically active
drainages.
Even so, there is reason to believe that river floors were not a major element of Mount Rainier's prehistoric resource base. The river valley landscapes experience resource limitations common to maritime forests generally. Indeed, because Mount Rainier's river valleys are too low for productive huckleberry habitat (at least for commonly collected varieties), too narrow for extensive ungulate habitat and too silty and lahar prone for productive anadromous fisheries, their usefulness to prehistoric populations may have been more for access to Mount Rainier itself, rather than for resources offered directly.
Subalpine Parkland
Up from the floodplains and above the maritime forest, dense forest cover gives way to clumped tree groups scattered among meadow communities. Sometimes referred to as the forest/tundra ecotone (Franklin and Dyrness 1973:248), these subalpine parklands typically appear as patchy associations of conifers interspersed with grassy meadowlands sandwiched between closed forest below and open tundra above. Because of high resource potential, and because they compromises distance between tundra and forest ecozones, I suggest that Mount Rainier's subalpine parklands are the most important places for focused seasonal human use during the prehistoric past–clearly not the only places, but the most intensively and repeatedly used over the long-term.
The subalpine zone's enhanced productivity lies in the maturity suppressing effect of heavy snowpack and short growing season. Under such circumstances, rapidly growing and reproducing species such as grasses, sedges, composite flowers, low shrubs, and plants with underground bulbs have an advantage over slower growing, longer-lived trees. Rapid growth plants also provide the best forage for ungulates as well as smaller mammals and birds. Locally dense dwarf huckleberries are good bear and bird habitat and can be exploited directly by humans. Subalpine parklands offer an effective compromise between closed forest and open space–meadows provide a good source of ungulate forage and edible flora, and tree patches provide protective shelter from predators and weather.
Talyor and Shaw (1927:12-13) also emphasize the subalpine zone's unique floral and faunal abundance.
...the Hudsonian Zone (above the narrow forested area), with its happy combination of open grassy park and subalpine flower garden on the one hand and pinnacle and glacier on the other, is without doubt the most attractive zone on the mountain. The shade of the deep Canadian forest is gone. Groups of handsome spirelike alpine firs and mountain hemlocks are set about the meadow borders or interspersed over the green expanses, always affording plenty of light and moisture to the grass and flowers. There is an abundance of food for birds and mammals, which are more conspicuous and probably more numerous in this zone than in any other in the park. The Hudsonian is the most desirable and the only favorable zone for camping away from the hotels, because only here (except at Longmire) can forage for horses be found [emphases added].
Closed Pacific maritime forests give way to patchy subalpine associations above about 5,200 ft on the wetter northwest, west and southern sides of the mountain; and above 5,800 ft on the drier northeastern side. Tree groups become increasingly patchy and stunted with elevation, ultimately giving way to scrubline vegetation and full alpine tundra at about 6,200 and 6,800 ft on windward and leeward sides respectively. Figure 2.8 shows subalpine associations at circa 5,400 ft in Mist Park in Mount Rainier's northwest quadrant. The view is taken from Mt. Pleasant Rockshelter site FS 72-02 (45PI433). Two additional prehistoric sites and two isolate finds have been documented in the near vicinity.
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| Mist Park Subalpine Meadows from Mt. Pleasant Rockshelter. East-northeast facing photo shows Sluiskin Mountain (jagged peaks at upper left-center), and Old Desolate Mountain, in the background. |
Patchy forest associations are dominated by Pacific silver fir on wetter sides of the mountain. Mountain hemlock tends to predominate on the dry side (see Figure 2.5). Typically, subalpine stands incorporate a higher frequency of mountain hemlock, subalpine fir (Abies lasiocarpa), and white bark pine (Pinus albicaulis) than present at lower elevation. Alaska yellow-cedar is locally present in low density. Near timberline, subalpine fir is one of the last tree species to give way to alpine tundra.
Subalpine Meadows
While tree patches are important for
shelter, our primary interest in subalpine and tundra habitats lies in
the productivity of their meadow communities. As with forests,
composition of subalpine meadows varies with sediment structure,
drainage, elevation, and solar exposure. Citing Henderson (1973),
Franklin and Dyrness (1973:252) identify five major meadow groups on
Mount Rainier: 1) Phyllodoce empetriformis-Vaccinium deliciosum
(red heather-dwarf huckleberry); 2) Valeriana sitchensis (lush
herbaceous); 3) Carex nigrians (dwarf sedge); 4) rawmark and low
herbaceous; and 5) Festuca viridula (grass or dry grass) (cf.,
Whitney 1983:42-43). Community associations within these groups is
highly variable, though here we focus only on dominant constituents.
Heather-dwarf huckleberry associations (Group 1 above) are most prevalent on gentle slopes with moderately well-drained soils. A good example are the south trending ridge near Mt. Ararat and parts of "Indian Henry's Hunting Ground"in the Park's southwest quadrant. Both heather and huckleberry are low-growing shrubs capable of forming nearly complete low ground cover mats. Franklin and Dyrness (1973:256) suggest that more purely dwarf huckleberry stands (such as those near Mt. Ararat) tend to be pioneer communities on burned habitats, and are succeeded either directly by forest (at lower elevation) or by more complex heather-huckleberry associations.
Ethnohistoric reports on the importance of dwarf huckleberry (V. deliciosum) are contradictory. Smith's (1964:160-161) sources refer to it variously as 1) of little economic importance because it grows too low to the ground and ripens too late in the year; and 2) gathered in quantity because the berry is large and low to the ground. It is plausible that the apparent contradiction is due to use as a buffering resource in years when lower elevation, taller V. alaskaense, ovalifolium and membranaceum varieties were not productive. In any case, dwarf huckleberry's subalpine co-occurrence with hunted game is likely to have ensured use minimally as a supplemental, if not staple, food item.
The lush herbaceous meadows (Group 2) are the richest and most diverse of the subalpine meadow communities (see Franklin and Dyrness 1973:256-262). These meadows develop on steep to moderate gradient, well watered, avalanche-prone slopes. They are common to the southern and western slopes of Mount Rainier. Specific floral composition varies. Community dominants listed by Henderson (1973) in Franklin and Dyrness include varieties of valerian (especially Velariana sitchensis), false hellebore (Veratrum viride), lupine (Lupinus latifolius), bistort (Polygonum bistortoides), sedge (Carex spectablilis), and monkeyflower (Mimulus lewisi). Actual composition, of course, is substantially more diverse. More important than specific floral composition is the capacity of these low maturity associations to provide forage for a variety of exploitable mammals such as elk, deer and marmots. If continuously maintained by frequent landslides, such communities may have been of substantial importance to prehistoric hunter-gatherers.
Black sedge (Carex nigricans) communities (Group 3) typically are found on relatively flat to rolling sites with short growing season due to late persisting snowpack and cold, wet soils (Franklin and Dyrness 1973:261). Floral diversity is relatively low and growth limited by the circumstances noted above. Local co-dominants include marshmarigold (Caltha biflora) and pedicularis (Pedicularis groenlandica).
Franklin and Dyrness' rawmark and low herbaceous category (Group 4) consists of poorly developed, pioneer associations in a variety of locations with well drained bouldery/gravely to sandy sediments (Franklin and Dyrness 1973:262-263). Slope is variable, ranging from alpine scree to low gradient regisols. Total plant cover varies from a low of about 20 percent to nearly complete. Dominant associations include saxifrage (Saxifraga tolmiei), luetkea (Luetkea pectinata), buckwheat-pussypaws (Eriononum pyrolaefolium-Spraguea umbellata), everlasting (Antennaria lanata), and aster-everlasting (Aster alpigenus-A. lanata).
Grassy parklands (Group 5) are particularly well developed on the drier northeastern side of the mountain. Two dominant community types intergrade on a moisture gradient (Henderson 1973 in Franklin and Dyrness 1973:263): fescue-lupine (Festuca viridula-Lupinus latifolius) in moist locations and fescue (F. Viridula-Aster ledophyllus) in drier places. Fescue-lupine associations are most commonly associated with level to low gradient parklands such as Sunrise Ridge and Grand Park. Fescue-aster associations are found on even drier steep, south facing slopes with coarse textures soils.
Subalpine Fauna
Subalpine communities were important
prehistorically both because they produced directly consumable plants
(e.g., huckleberries and alpine lily), and because they supported
relatively high bird and mammal populations as well. A sample of common
species can be gleaned from Taylor and Shaw (1927:13), Whitney
(1983:42-43) and Schamberger (n.d.:21-23) summary accounts. The birds
reported by these sources include golden eagle, saw-whet owl, calliope
hummingbird, Clark nutcracker, Cassin purple finch, western sparrow,
warblers, mountain chickadee, Townsend solitaire, hermit thrush,
mountain bluebird, northern three-toed woodpecker, Hammond and
olivesidedflycatcher, golden-crowned kinglet, gray jay, red-breasted
nuthatch and evening grossbeak. Mammals include red fox, Washington
weasel, Canada lynx, mountain lemming mouse, Rainier meadow mouse,
large-footed mouse, red-back, Oregon and heather voles, Rainier pocket
gopher, hoary marmot, yellow pine and Townsend chipmunk, mantled ground
squirrel, snowshoe hare cony (pika), pine marten, coyote, black bear,
mountain lion, elk and black-tailed deer. Though more common to alpine
tundra, mountain goats occasionally graze in upper elevation subalpine
associations and move through them to upper forest zones to find winter
shelter. Ptarmigan, common in tundra associations, also are found in
subalpine places.
At first glance, faunal variation may not appear markedly different from the forest proper. However, overall diversity is greater and, importantly, seasonal abundance of larger and fatter (i.e., energy rich) animals is substantially higher. Animals such as black-tailed deer, elk, black bear, and marmots find better forage in the meadow/forest ecotone than in the closed forest (except for burn areas). Assuming game animals are not over hunted, the subalpine combination of high return faunal and floral species should have been attractive to human exploitation throughout the prehistoric past.
Subalpine Parkland, Land-Use and Archaeology
The primary
point to be taken in the discussion above is that subalpine communities
substantially increase the abundance and diversity of low
maturity flora over that of lower elevation maritime forests. Enhanced
forage, in turn, favors increased faunal abundance. Assuming humans tend
to structure their annual round to seek out productive habitats, we
should expect subalpine parklands to have been the primary focus of
human hunting and gathering activity throughout the prehistoric past.
While burns and landslides also tend to be resource rich, only subalpine
and alpine zones do so in a manner that is stable over a long period of
time. If subsistence resource availability was the principal variable
attracting prehistoric people to Mount Rainier, it is reasonable to
expect Mount Rainier's archaeological record to reflect a bias toward
low maturity subalpine to alpine landscapes.
It should be noted in closing that subalpine communities exist in a state of dynamic tension between lower forest boundaries and the upper tree or shrubline (krummholtz) boundary with alpine tundra (see Franklin and Dyrness 1973:276-284). In the subalpine ecotone, density of tree stands decreases with elevation as dictated by local effects of wind, fire, avalanches and snowpack; and by the overarching effect of decreasing temperature. In general, trees invade subalpine meadows during prolonged periods of stable warm weather, and retreat in the face of cold or unstable conditions. That is, parkland meadows tend to shrink and move upslope during periods of climatic warming (providing fire frequency does not increase); and expand and move downslope during cool, excessively dry and/or unstable circumstances. If subalpine communities are as important to prehistoric hunters and gathers as suggested here, it is important to develop a thorough understanding of Holocene climatic variables in regard to their implications for the resource productivity of these zones.
Alpine Tundra
Upper elevation tree clumps and scrubline mats of Englemann spruce (Picea englemannii) and subalpine fir give way to open alpine communities at about 6,200 to 6,800 ft on Mount Rainier. Alpine tundra extends upward to the firnline boundary with permanent snowfields at circa 7,600 ft. Because of Mount Rainier's great height and geological youth, much of the circa 7,600 ft upper boundary with permanent snowfields is characterized by rock and essentially vegetation free glacial rubble.
Figure 2.9 shows alpine tundra habitat and a pair of mountain goats (Oreamnos americanus) on Burroughs Mountain in the northeastern side of Mount Rainier. Fryingpan Glacier in the background and lower reaches of Emmons Glacier at photo right show increasingly barren glacial scree slopes and glacial scour at the alpine interface with standing snowfields.
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| Figure 2.9 Mountain Goats on Burroughs Mountain Alpine Tundra. (South facing photo shows Fryingpan Glacier and White River headwater snow fields in the background.) |
Alpine Tundra Flora
The greatest expression of alpine communities on Mount Rainier is on the
drier northeastern slope at places like Goat Island Mountain, Burroughs
Mountain, and terrain near Frozen Lake and Mt. Fremont. The growing
season is short with substantial diurnal temperature variation. Terrain
is open with tundra grasses and forbes growing at moderate density over
variously exposed volcanic lapili and shallow lithosols. Specific plant
associations vary with local conditions. At least at lower elevations,
subalpine meadows extend with minimal constituent variation into the
open tundra. Dominant plant associations on the northern slope were
studied by Hamann (1972) and reported by Franklin and Dyrness (1973:287)
as follows:
Black crowberry/prairie lupine (Empetrum nigrum/Lupinus lepidus); north-facing fellfields.
Kinnikinnik/coast goldenrod (Arctostaphylos uva-ursi/Solidago spathulata); south-facing fellfields.
Blunt-leafed sandwort/prairie lupine (Arenaria obtusiloba/L. lepidus); pioneer on gentle slopes.
White heather/alpine aster (Phyllodoce glanduliflora/Aster alpigenus); moistest alpine environments.
Coiled pedicularis/showy sedge (Pedicularis contorta/Carex spectabilis); forms well-developed turf.
Golden fleabane/prairie lupine (Erigeron aureus/L. lepidus); forms well-developed turf.
Spreading phlox/mountain sandwort (Phlox diffusa/Arenaria capillaris); seral to pedicularis/sedge.
Alpine Fauna, Land-Use and Archaeology
Floral and faunal
diversity decreases above the scrubline. Successful animal species are
those suited to grazing on the low ground flora, cope with unstable
weather without tree shelter, and make use of high elevation snowfields
and cleavers for predator escape. Mountain goats, pika, white-tailed
ptarmigan, marmots and other smaller rodents are common alpine tundra
feeders during its brief July through September summer. Ravens, larks,
finches and piptis (see Taylor and Shaw 1927:15; Whitney 1983:43-44;
Schamberger n.d.:22-23) also use subalpine habitats. While extirpated
from the Park by the late 1800s or earlier, elk are also likely to have
been warm season grazers in the lower alpinesubalpine boundary. Because
of the brevity of alpine summers, by early to mid October, game becomes
virtually unavailable. Pika and marmots move to underground dens and elk
migrate to lower-elevation forage. Goats move downslope a short distance
to upper forest wintering areas such as Tum Tum Peak on Mount Rainier's
southwest slope (Schamberger n.d.:75).
It is likely that goats, elk and perhaps marmots provided sufficiently productive food and wool sources to attract human predation in the alpine tundra zone. In the historic period, goat wool was highly prized for its beauty and warmth (see Eells 1985). Indeed, though other animals undoubtedly are present, to date the only unambiguously identified faunal remains in archaeological context are goat teeth from Fryingpan Rockshelter (FS 63-01 [45PI43]) (Gustafson:1983:27-28). Marmots may have been important for their fat. The benefit of elk, of course, lies in large body size and correspondingly high meat return per animal killed.
Because of unstable weather and availability of fewer specific resources, it is probable that alpine foraging tended to be carried out by small task-specific hunting groups with short duration camping, ambush, butchering or lithic procurement stops. If so, we should expect the alpine/upper subalpine archaeological record to reflect such constraints in the form of more functionally limited tool kits and lower artifact density (except at lithic quarries and butchering sites such as FS 86-01 [45PI407] at Frozen Lake). These qualities contrast with the subalpine to subalpine forest boundary where resource variety is greater and weather is milder. Lower-elevation conditions favor longer-term use, probably by a higher frequency of mixed sex gathering and hunting parties. We expect subalpine/upper forest margin sites should exhibit the full rage of sites common to alpine habitats plus a number of higher artifact count, multi-task assemblages consistent with more sustained and varied activities, and probably with more repetitive use. It is plausible, too, that select lower elevation places functioned as base camps from which more limited task gathering and hunting parties operated. Indeed, that argument will be made for three of Mount Rainier's lower subalpine/upper forest sites–FS 95-10 (45PI429) in the Park's southwest quadrant, and FS 71-01 (45PI438) and FS 90-01 in the northeast quadrant.
Perpetual Snowfields and Glaciers
Perpetual snowfields with standing glaciers and associated barren rubble fields range from firnline at 7,600 ft to Mount Rainier's 14,410 ft summit. Individual glacial tongues and young recessional moraines extend downslope in major glacial valleys to circa 5,500 ft. The largest of these–Carbon, Winthrop, Emmons, Ingraham, Nisqually, Tahoma and Mowich Glaciers–extend to below 5,000 ft.
Above the firnline, vegetation is suppressed by snow and ice mass. Floral species are limited essentially to mosses and lichens with very few grasses and flowering plants on rocky cleavers and other seasonally ice-free areas (Brockman 1947:6). Fauna are limited as well. A few marmots, pika, mice and shrews have been observed as high as 8,000 to 10,000 ft. Mice and even bear tracks have been reported at the summit (Schamberger n.d.:22). Clearly, such events are rare, and high mountain edible biomass is negligible. Perhaps the single exception to the pattern the presence of mountain goats which take advantage of glaciers and high rock fields for travel, observation, and escape. For the most part, however, Mount Rainier's glacial zone is largely devoid of economically useful plant and animal life.
Given logistical difficulty, relatively high risk and low return, we assume that prehistoric human use of high elevation Mount Rainier was limited to goat hunting, possible ceremonial use of the alpine/glacier interface, and very infrequent use of higher elevation snow and boulder fields. The highest elevation prehistoric archaeological finds presently documented on Mount Rainier are two isolated projectile points found at 7,500 ft on Success Cleaver (IF 01-70 in the southwest quadrant). Their presence is consistent with use of the locality as a hunting stop at the upper alpine/lower permanent snowfield boundary. We expect similar finds, perhaps associated with low stacked rock features or talus pits to be documented as cultural resource studies continue.
The following set of color maps (Figures 2.10, 11, 12 and 13) show Mount Rainier environmental zones and formally documented archaeological sites in four Park quadrants. Zonal boundaries are derived from environment data logged into the Park's geographic information system (GIS). Basic data on forest, subalpine and alpine boundaries were plotted from aerial photographs. They are intended to model climax vegetation associations, excluding effects of short-term fire alteration. Perpetual snowfield boundaries include standing glaciers, permanent snowpack and a 100 ft buffer to accommodate glacial scree slope rubble. High energy floodplains are those that have experienced major documented floods and/or lahars. These maps provide the best precision presently available for displaying environmental zones and for graphically illustrating association with documented prehistoric sites. The clear association of prehistoric sites with subalpine and alpine settings is consistent with ecological land-use arguments offered above, in ethnohistoric accounts collected by Smith (1964), and discussed in the following sections.
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| Figure 2.10 Mount Rainier National Park. Northwest Quadrant. (click on image for an enlargement in a new window) |
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| Figure 2.11 Mount Rainier National Park. Northeast Quadrant. (click on image for an enlargement in a new window) |
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| Figure 2.12 Mount Rainier National Park. Southwest Quadrant. (click on image for an enlargement in a new window) |
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| Figure 2.13 Mount Rainier National Park. Southeast Quadrant. (click on image for an enlargement in a new window) |
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