Cover

Author

This report is published by the Pacific Northwest Research Station under an agreement 

with the Ecological Reserves Council and in cooperation with the Bureau of Land 

Management, U.S. Department of the Interior, Anchorage, Alaska.

An unvegetated alpine exposure of serpentinite blown free of snow (upper left) shows 

the striking toxic effects of this special natural bedrock type, and a path of destroyed 

vegetation (upper right) along a slope marks a large earthslide in the winter: these two 

characteristic features give the Serpentine Slide Research Natural Area its name. Forests of mature white spruce can be seen on the south-facing slopes along the earthslide. 

Beaver lodges, a dam, and a pond occur at the base of warm, dry, open limestone and 

dolomite slopes on the Beaver Creek flood plain (lower left). The northern wood frog 

(Rana sylvatica) is common along the edge of beaver ponds and meadows (lower right) 

and develops to large sizes in the long, warm days of summer.

GLENN PATRICK JUDAY is assistant professor of forest ecology and Alaska ecological reserves coordinator, Agricultural and Forestry Experiment Station, University of 

Alaska Fairbanks, Fairbanks, Alaska 99775.
The concept of establishing natural areas for education and scientific research is not 

new. As early as 1917 in the United States, the Ecological Society of America set up 

the Committee on the Preservation of Natural Conditions and published its findings in 

1926. Other professional societies-Society of American Foresters, the Society of Range 

Management, and the Soil Conservation Society of America-proposed programs to 

identify and set aside areas where natural forest, range, and soil conditions could be 

preserved and studied.

The name Research Natural Area (RNA) was adopted and, in 1966, the Secretaries 

of Agriculture and the Interior formed the Federal Committee on Research Natural 

Areas to inventory research sites established on Federal land and to coordinate their 

programs. A 1968 directory from the Federal committee listed 336 RNAs nationwide, 

of which 13 were in Alaska.

By 1969, the International Biome Program (IBP) was active across the United States, 

and a tundra biome team was headquarted at the University of Alaska. The IBP 

proposed the establishment of an ecological reserves system for Alaska—“field sites 

uniquely suited for natural research and education. All identified sites...to illustrate one 

or more ecological phenomena particularly well.” Called Research Natural Areas in 

the United States, such areas are still called Ecological Reserves in Canada and other 

parts of the world.

In 1973, the Joint Federal-State Land Use Planning Commission for Alaska assumed 

the role of lead agency in establishing Research Natural Areas and provided badly 

needed funds and staff support. By fall 1976, a resource planning team of the commission had prepared a comprehensive plan for establishment and management of the 

RNAs. A total of 222 sites, representing a wide range of physiographic regions and 

planning areas in the State, was recommended.

In 1976, the commission formed the Ecological Reserves Council to represent Federal, 

State, and private agencies. It also entered into a contract with the University of Alaska 

to assist in carrying out the council’s recommendations.

Present members of the Ecological Reserves Council are:

U.S. Department of the Interior:

Bureau of Land Management

Fish and Wildlife Service

National Park Service

U.S. Department of Agriculture, Forest Service:

Alaska Region

Pacific Northwest Research Station

National Marine Fisheries Service

Alaska Department of Fish and Game

Alaska Federation of Natives

University of Alaska Fairbanks

A management-coordinator position for gathering on-the-ground data for the RNAs 

Alaska has been filled since 1977 by Dr. Glenn Juday-originally under the planning 

commission, then by contract between the University of Alaska and the USDA Forest 

Service.

Foreword
In 1985, the Ecological Reserves Council proposed to the Director of the Forest Service’s Pacific Northwest Research Station that the reports for the RNAs, be published 

formally by the Station. The Station agreed to publish them in the General Technical 

Report series.

KENNETH H. WRIGHT (Retired)

USDA Forest Service

Juday, Glenn Patrick. 1992. Alaska Research Natural Areas. 3: Serpentine Slide. 

Gen. Tech. Rep. PNW-GTR-271. Portland, OR: U.S. Department of Agriculture, 

Forest Service, Pacific Northwest Research Station. 66 p.

The 1730-ha Serpentine Slide Research Natural Area (RNA) is located in central 

Alaska in the White Mountains National Recreation Area. It is managed by the U.S. 

Department of the Interior, Bureau of Land Management, Steese-White Mountains 

District. Serpentine Slide was selected as a Research Natural Area (RNA) because 

it contains an alpine exposure of serpentinite; a 9-ha natural earth flow that has destroyed most vegetation in its path; bottom-land white spruce and balsam poplar forests 

growing on coarse gravels and sands of a major clearwater river flood plain; and warm, 

dry hill prairies on steep south-facing slopes. The area also contains several beaver 

dams, lodges, and ponds. Beaver-created habitats support typical wetland species including ducks and the northern wood frog. Open gravel bars and the high-quality, clear 

water of Beaver Creek provide nesting and breeding habitat for shore birds, especially 

the semipalmated plover. The Beaver Creek bottom-land corridor is a locally important 

habitat for grizzly bear, which use the RNA intensively in particular seasons. The variety of natural features of geologic, hydrologic, botanic, aquatic, and wildlife interest 

and the opportunity to monitor natural change in a locally diverse environment make 

Serpentine Slide RNA an outstanding scientific and educational resource.

Concentric zones around serpentinite exposures in the RNA show increasingly toxic 

effects on plants. A widespread alpine plant in Alaska, Bupleurum triradiatum, is the 

vascular species most tolerant of serpentinite, but no special serpentine-adapted plant 

species have been discovered in the RNA. The center of serpentinite exposures in the 

RNA is naturally devoid of all plant life except an orange crustose lichen.

The earth flow has been periodically active since at least the early 1950s. Dolomite and 

limestone are exposed on the lower slopes in the northeast portion of the RNA. The 

banks and overflow channels of Beaver Creek are made up of large to mediumsized 

smooth, rounded gravels with little fine sediments. The flood plain and terraces along 

the Beaver Creek portion of the RNA are generally made up of gravels and coarse 

sand, in contrast to the fine silts, sands, and clays of terraces and flood plains along 

typical northern Alaska rivers that carry glacial sediments.

Belted kingfishers excavate nesting burrows in exposed river cutbanks along Beaver 

Creek. Goshawks use extensive stands of mature and old-growth white spruce forest 

and adjacent successional and wetland habitats

Abstract
Three plants collected in the RNA, Carex eburnea, Artemisia alaskana, and Agropyron spicatum, are growing beyond their previously reported distribution in Alaska. A 

150-year-old flood-plain white spruce forest supports about 40 m2/ha live tree basal 

area and contains dominant trees from 30 to 45 cm in diameter at breast height (d.b.h.) 

and up to 30 m tall. An upper elevation, south-slope white spruce forest supported 36 

m2/ha, dominant trees 20 to 36 cm d.b.h. and a maximum of 19 rn tall.

Keywords: Alaska, beaver, Castor canadensis, earthslide, ecosystems, goshawk, Accipiter gentilis, grizzly bear, Ursus arctos, hill prairie, Research Natural Area, Natural 

Areas (Research), northern wood frog, Rana sylvatica, old-growth forest, scientific 

reserves, serpentine, semipalmated plover, Charadrius semipalmatus, white spruce, 

Picea glauca.

1 Introduction

6 Access and Accommodations

6 Parking, Roads, and Rights-of-Way

8 Structures and Trails

8 Reasons for Establishing the Research Natural Area

14 Environment

14 Climate

18 Hydrology

22 Geology

28 Soils

31 Biota

31 Vegetation

49 Fauna

60 History of Disturbance

60 Research

61 Maps and Aerial Photographs

62 Acknowledgments

62 English Equivalents

62 Literature Cited

Contents

1

Serpentine Slide is an area of the White Mountains National Recreation Area (WMNRA) in central Alaska that contains an exposure of the ultramafic rock type, serpentinite (in this area the metamorphosed form of harzburgite), and a major earthslide. 

Serpentine is a hydrothermally altered, iron- and magnesium-rich rock presumed to 

originate as new crust at seafloor spreading centers. Serpentine rocks form soils that 

lack calcium and have magnesium and heavy metals at levels toxic to most plants, 

except those specially adapted to grow on them (fig. 1). A natural zone of geologic 

weakness on a steep slope overlooking Beaver Creek near the serpentinite exposure 

has produced a large earthslide (fig. 2). The name Serpentine Slide was derived from a 

combination of these two features.

Serpentine Slide Research Natural Area (RNA) is managed by the Steese-White 

Mountain District Manager, Bureau of Land Management, U.S. Department of the 

Interior; district headquarters is in Fairbanks (1150 University Avenue, Fairbanks, AK 

99709-3854). Permission is not needed for educational use and observational, nondestructive research, but scientists interested in using the area are urged to contact the 

district manager and the Alaska Ecological Reserves Coordinator, Agricultural and 

Forestry Experiment Station, University of Alaska Fairbanks, Fairbanks, AK 99775, to 

outline activities planned.

The WMNRA was established by the Alaska National Interest Lands Conservation 

Act (ANILCA) of 1980. Section 1312 of ANILCA recognizes the scientific and fish 

and wildlife values of the WMNRA and requires their protection. A list of natural 

features of scientific interest was developed as part of the resource inventory of the 

WMNRA.1 This list was the basis for the nomination of three Research Natural Areas 

(RNAs): Serpentine Slide, Mount Prindle (Juday 1988), and Limestone Jags (Juday 

1989).

1 Juday, G.P.; Knapman, L.; Field, L.; Taylor, D. 1982. A preliminary 

report of ecological reserve project activity, Fairbanks District BLM: 

identification of type needs and candidate Research Natural Areas in 

the White Mountains NRA-Steese NCA. Fairbanks, AK: Bureau of 

Land Management, Steese-White Mountains District. Unpublished 

report on file. 9 p.

Introduction
2

The draft land and resource management plan for the WMNRA proposed a 1730-

ha Serpentine Slide RNA in 1984 (Bureau of Land Management 1984). After public 

review and comment, Serpentine Slide RNA was established by a revised plan adopted 

in 1986 (Bureau of Land Management 1986). The approximate center of Serpentine 

Slide RNA lies at 65° 43’ N., 147° 31’ W. (fig. 3). The setting of Serpentine Slide Research Natural Area (RNA) within the WMNRA is shown in figure 4.

The location of the RNA within the public land survey system and topographic contours are shown in figure 5. Elevations in the RNA range from 975 m in the mountains 

of the northern perimeter to 320 m along Beaver Creek as it flows north toward the 

Yukon Flats.

The WMNRA plan contains special management direction for the three RNAs, which 

total about 5200 ha or a little more than 1 percent of the area. The guiding principle 

of management is to prevent unnatural activities that modify ecological processes. No 

mineral leases will be issued in RNAs and off-road vehicles (ORVs) are not allowed. 

Scientific research and educational use are encouraged; passive recreation, including 

hunting, is allowed. Long-term studies can be conducted in RNAs with minimal interference and the assurance that management or resource development will not conflict 

with research. In return, scientists should notify the district manager of their proposed 

uses, abide by any applicable regulations, and provide the Bureau of Land Management 

with published results or progress reports.

The relation of management zones to Serpentine Slide RNA is shown in figure 6. A 

large, primitive recreation management zone occupying about 191 100 ha, or 47 percent of the WMNRA, borders Serpentine Slide RNA to the east and west. The primitive zone is closed to mineral leasing and to motorized vehicles other than snowmobiles in winter or vehicles under special permit.
3
4

Beaver Creek was designated a National Wild River by ANILCA. The Beaver Creek 

Wild River corridor occupies about 28 300 ha or 7 percent of the WMNRA, and it 

overlaps the southern portion of Serpentine Slide RNA (fig. 6). The river corridor is 

generally managed in the same way as the primitive recreation zone, except that motorized boats are currently allowed on the river. The river corridor is expected to be the 

focus of increasing recreation activity when access improves. The WMNRA plan did 

not implement onsite restrictions or onsite recreation management activities, but it authorized these measures if they are needed to protect resource values and public health 

and safety (Bureau of Land Management 1986). A semiprimitive motorized recreation 

zone abuts the northern border of Serpentine Slide RNA (fig. 6); it is open to mineral 

leasing (other than placer mining) and to ORVs of less than 700 kg. Further details of 

management direction are available in the WMNRA plan (Bureau of Land Management 1984) and the Record of Decision (Bureau of Land Management 1986).
5

The principal historical uses of the Serpentine Slide RNA have been geologic study, 

mineral prospecting, biological research, and hunting. Mertie (1917) began geologic 

study and prospecting in the early 1900s. The work of Weber and Chapman in the 

area in the 1960s led to the first bedrock geology map of the Livengood quadrangle 

(Chapman and others 1971). In the 1950s and early 1960s, a Norwegian botanist, Olav 

Gjaerevoll (1958, 1963, 1967), conducted the first taxonomic work in this portion of the 

State. He collected mainly plants of mountain and limestone habitats in areas to the 

south, but he also collected along the Beaver Creek corridor. Serpentinite outcroppings 

were identified in 1967 (Foster 1968), the first of their type documented in Alaska. The 

documentation of the RNA in 1982, 1983, and 1987 reported here resulted in the first 

extensive plant collections in the RNA, observations of plant responses to serpentine 

in Alaska, and the establishment of permanent plots in upland forest, bottom-land 

forest, and at tree line. The U.S. Geological Survey evaluated the geology and mineral 

resources of the WMNRA in 1986 and 1987 (Weber and others 1988). Recreational 

activity in the area consists mainly of float trips on Beaver Creek and fly-in fishing.
6

There is no road access to Serpentine Slide RNA. Visitors can reach the area by 

aircraft, snow machine, or a combination of river and cross-country travel. Serpentine Slide is about 115 km north of Fairbanks International Airport (fig. 4). Helicopter 

access to the RNA is excellent; landing zones are available in open alpine regions, on 

gravel bars on Beaver Creek, in beaver meadows, and on serpentinite barrens. The frozen surface of Beaver Creek can be used for skiplane landings when snow conditions 

are suitable. During the warm season, small fixed-wing aircraft with large tires occasionally use gravel bars along Beaver Creek for takeoffs and landings, although this 

form of access is not recommended. Floatplanes can use the surface of Beaver Creek 

near the RNA during high water. Floatplane operations are possible for nearly the entire warm season on Beaver Creek below its confluence with Victoria Creek, which is 

about 40 km east-northeast (downriver) from the RNA. The WMNRA plan authorizes 

a primitive landing strip near the mouth of Victoria Creek; the selection of a site and 

construction of the airstrip must await environmental analysis and funding.

Access and

Accommodations

Parking, Roads, and

Rights-of-Way
7

Winter access to the area is good. The nearest road to Serpentine Slide RNA is the 

Elliott Highway, 40 km to the southwest (fig. 4). Two well-used snowmobile trails, 

the White Mountain Winter Trail and the Colorado Creek Trail, connect the Elliott 

Highway to Beaver Creek (fig. 7). The frozen flood plain and surface of Beaver Creek 

itself make a well-used snowmobile route south of the RNA as indicated by tracks in 

the snow. Snowmobile travel on Beaver Creek drops off considerably from Serpentine 

Slide northward. Visitors should be aware of persistent open water leads or channels 

on Beaver Creek and check with the Bureau of Land Management (BLM) for information on current local conditions.
8

Beaver Creek is a highly desirable float trip destination. It is near the facilities and visitor services of Fairbanks but offers a true wilderness river experience. The summer climate includes more warm and sunny days than any other region of Alaska; occasionally Beaver Creek becomes warm enough for a brief swim. The water of Beaver Creek 

is exceptionally clean and clear. Aquatic productivity (including sport fish) in Beaver 

Creek is enhanced by buffering and nutrient enrichment from limestone in the middle 

and upper portions of the watershed. The Beaver Creek riparian zone is a significant 

wildlife corridor, thus offering viewing and hunting opportunities to visitors.

Most river expeditions to Beaver Creek are flown in because no road reaches Beaver 

Creek. The White Mountains Resource Plan approved construction of a road, campground, and visitor facilities at the head of Beaver Creek. The new facilities will allow 

boat access about 80 km upstream from Serpentine Slide RNA. The route for the 

road has been approved and surveyed. Construction will begin when BLM obtains an 

appropriation for the project. Float trips to Serpentine Slide will presumably become 

more numerous with improved access.

There are no structures in or immediately adjacent to the RNA. A small cabin is located along Beaver Creek about 5 km downstream, and two private cabins are 22 and 

30 km upstream (south) of the RNA. None of the structures is permanently inhabited. 

Serpentine Slide is part of a wilderness environment, and visitors must be prepared 

for a high degree of self-sufficiency. The WMNRA plan approved a public use trail 

and a shelter or cabin to be constructed about 19 km east of the RNA in the mountains 

west of Victoria Mountain. Detailed site planning and construction are contingent on a 

Congressional appropriation.

The plan also provides for a ridge trail above Beaver Creek. One trailhead is proposed 

for a site along Beaver Creek about 5 km downstream from the RNA.

The criteria for establishing RNAs in Alaska are called type needs (Juday 1983). Type 

needs are plant communities, rare plants, geologic features, and animal species that are 

characteristic of a given region and that are necessary for a complete and representative system of RNAs. The special character of type needs, such as their rarity, habitat 

requirements, or sensitivity, guide the management of the particular RNAs they occur 

in. Juday and others (see footnote 1) defined type needs used in the search for RNAs in 

the WMNRA. Table 1 is a list of the type needs found in Serpentine slide RNA and includes two geologic features and nine plant communities. The significance of the RNA 

for wildlife was revealed by site documentation, and the five animal species in Table 1 

are a supplement to the original list. These animal species are especially characteristic 

of the RNA and offer special research and educational opportunities; they should be 

given status equal to the original type needs in future management and research in 

Serpentine Slide RNA.

Structures and Trails

Reasons for 

Establishing the 

Research Natural 

Area
9

Table 1-Natural feature type needs used In the selection of the Serpentine Slide 

Research Natural Area

Type needs Comments and definitions

Geologic features:

 Serpentinite Bedrock exposure and shallow residual

 soils across a range of elevations from

 alpine uplands to Beaver Creek

 Faultline features High-angle thrust fault or suture zone

 providing evidence on the accretion of

 terranes or normal faults, or both,

 showing surface geomorphic evidence

 of faultline shifting or movement

Plant communities:

 Forest—

 Moist white spruce slope forest Picea glauca/feathermoss, Picea

 glauca/Linnaea borealis-Equisetum

 silvaticum and Picea glauca/Rosa

 acicularisa

 Wet black spruce-sphagnumb Black spruce open needleleaf forest

 (includes several level V communities)a

 Moist balsam poplar flood-plain

 forestb Balsam poplar closed broadleaf forest

 (includes more than one level V

 community)a

 Moist balsam poplar-spruce

 flood-plain forestb Populus balsamifera-Picea

 glauca/Alnus/Equisetuma

 Shrub—

 Wet willow-alder drainageway

 tall shrub Alder-willow closed tall scrubs

 Moist willow flood-plain tall

 shrubb Willow closed tall shrub (includes

 Salix alaxensis and other level V

 communities)a

 Moist alder slope tall shrub Alder-willow closed tall scruba

 Herbaceous—

 Snowbed herb-graminoid meadow Alpine herb-sedge (snowbed)a

 Barren and lichen—

 Foliose lichen Foliose and fruticose lichena

 Crustose lichen rocks Crustose lichena

Animal species:c

 Amphibian—

 Northern wood frog (Rana sylvatica)
10

Serpentine Slide RNA includes portions of one of the largest surface exposures of 

serpentinite in Alaska, a geologically and ecologically special and interesting rock type 

(fig. 8). Serpentine exposures are often relatively small because they are transported 

fragments of deep-ocean crustal material usually wedged among slivers of unrelated 

terranes. Serpentine forms under very specific conditions characteristic, if not diagnostic, of crustal materials emerging at seafloor spreading centers. These diagnostic 

characteristics make serpentine rocks useful in understanding the origin and history of 

the continental landscapes they have been incorporated into. The predominant mineral 

in serpentine is usually olivine, which gives a shiny, lustrous, dark-green appearance; 

asbestos fibers are often present.
11

In all the Earth’s major biomes, from the tropics to polar regions, serpentine and other 

related ultramafic rocks support a very unusual flora that often includes species locally 

adapted to grow in the special conditions these rocks produce (Brooks 1987). Walker 

(1954) notes that plants growing on serpentine must be “...tolerant of low calcium levels, and, in addition, be tolerant of one or more of the following: high concentrations 

of chromium and nickel, high magnesium, low levels of major nutrients, low available 

molybdenum, drought, and other undesirable aspects of shallow stony ground.”

The large earthslide found in the RNA is an unusual feature in interior Alaska and 

appears to be chronically active. The fractured bedrock exposed by the landslide looks 

much like strip mine tailings (fig. 9). Studies of natural ecological succession on the 

landslide might identify plant species or varieties that could be used to revegetate strip 

mines or other drastically disturbed lands in forest regions of interior Alaska.

Serpentine Slide includes a diversity of soils ranging from semiarid limestone and 

dolomite (fig. 10) to coarse flood-plain sands and gravels, alpine tundra permafrost, 

bottom-land permafrost, mature hardwood and conifer profiles, geochemically unique 

serpentine, and young, rich alluvium.

The hydrology and river morphology of the RNA are of special interest. Much of 

interior Alaska has a dry climate; the density of streams across the landscape is low. In 

interior Alaska, most large rivers that have extensive watersheds carry turbid glacial 

meltwater. Beaver Creek carries no glacial sediment and its water is especially clear 

(fig. 11). The Beaver Creek flood plain in the RNA is being formed by redeposition of 

alluvium rather than by the rise of the river from its bed as in a braided glacial-river 

flood plain.

Serpentine Slide RNA contains bottom-land old-growth white spruce (Picea glauca

(Moench) Voss) and successional shrub and balsam poplar (Populus balsamifera L.) 

forest communities. Most studies of bottom-land forests in central Alaska have been 

conducted on aggrading braided glacial-river systems with nutrient-rich mixtures of
12

fine sands and silts. The bottom-land plant communities in the RNA represent an 

interesting variant of these important vegetation types in interior Alaska. The bottom 

lands of the RNA support forests that have developed on coarse-textured soils, predominantly smooth, rounded river gravels overlain with variable amounts of sand or a 

humic layer (fig. 12).

The extensive south-facing slopes of the RNA support a relatively productive mature 

or old-growth white spruce forest of trees notably large for the elevation and northern 

latitude of the area. Bluff grasslands are found on the steepest south-facing slopes at 

low elevations just above Beaver Creek. Bluff grasslands are rich in plant species and 

contain some uncommon or range-limited species at the northern limits of their distribution.
13

Exposed stony gravels along the active flood plain of Beaver Creek are ideal nesting 

habitat for shore birds; many shore bird species do not construct a nest but simply lay 

eggs that match surrounding rocks in color, size, and pattern. The semipalmated plover 

is conspicuous in the active flood plain of the RNA during summer as it tries to divert 

intruders from its eggs camouflaged among the rocks with loud cries and a display 

simulating an injured wing.

Goshawks have been seen in mature white spruce forests of the RNA. Goshawk nesting pairs in interior Alaska require large areas of habitat-from 40 to 370 km2

 (McGowan 1975). The Beaver Creek valley is an area of intensive grizzly bear use. Serpentine Slide RNA supports a large population of beaver that have major effects on the 

flood-plain environment. Beaver have constructed a network of dams and ponds that 

use sloughs, terraces, and water from streams draining the slope north of Beaver Creek 

(fig. 13). Beaver ponds create habitat for furbearers, ducks, and fish. Lush meadow 

habitats develop as beaver ponds fill in or when they drain after beaver dams are abandoned (fig. 14). Northern wood frogs are common in warm shallow water at the edge 

of meadows; frogs in the RNA are large for an area so far north.
14

Serpentine Slide experiences a highly continental climate with large diurnal and annual temperature variations and generally low precipitation and humidity. The RNA is 

in the region of Alaska reporting the highest and lowest temperatures for the State. No 

climatic data are available from Serpentine Slide RNA, but a 17-year record (1963-79) 

is available from a National Weather Service station 122 km to the east-northeast at 

Central, Alaska (65° 32’ N, 144° 48’ W, 265 m elevation).

The climatic data from the Central station probably are representative of conditions 

along the Beaver Creek lowlands in the RNA. Serpentine Slide and Central are at low 

elevations on the southern edge of the Yukon Flats and at about the same latitude near 

the mountains of the Yukon-Tanana upland. The major climates in the RNA also can 

be inferred from studies of the relation of climate to vegetation and topographic position done elsewhere in interior Alaska (Haugen and others 1982, Slaughter and Viereck 

1986). The major climatic types in the RNA can be characterized as (1) permafrostdominated cold air inversion basins on the Beaver Creek lowlands, including permafrost-free forest environments along Beaver Creek; (2) south-slope taiga at 300 to 800 

m elevation; (3) steep, low-elevation bluffs with strong precipitation deficits and high 

radiant energy budgets; and (4) cold and windy alpine tundra above 850 m elevation.

Figure 15 compares the record of mean annual temperature at Central with University 

Experiment Station (UES) near Fairbanks, which has the longest continuous climatic 

record available for any interior Alaska station. Temperature trends at Central correspond well with those at UES, although Central is distinctly colder than UES. During 

the 1963-79 overlap period when data are available from both stations, Central experienced a mean annual temperature of -6.6 °C (sd ± 1.25), which is 3.8 °C (sd ± 0.51) 

colder than UES and well within the range of temperatures at which permafrost forms. 

Lower elevation and midelevation south-facing slopes in the RNA support forest types 

typical of permafrost-free sites, thereby indicating that temperatures are warmer there. 

The highest elevations in the RNA support alpine vegetation on harsh wind-blown 

sites (fig. 16) that are typically colder than midslopes and lowlands during the summer 

growing season.

Environment

Climate
15

Mean annual temperatures at Central follow the trends common to interior Alaska stations (Juday 1984b), which include a strong warming trend from 1900 to 1940, cooling 

until 1975, and warming to record levels of sustained warmth in the 1980s.
16

Figure 17 shows the length of the growing season at Central. Many years are interrupted by a midseason frost, although cold-adapted species tolerant of -2 to -4 °C temperatures can still experience a 70- to 100-day growing season. The Central data are 

characteristic of a low-elevation cold air collection “frost pocket.” The RNA contains 

similar sites but also has midelevation south-facing slopes that probably experience a 

longer frost-free season. Alpine sites probably experience a somewhat less variable but 

consistently shorter growing season.

The primary sources of moisture reaching the Serpentine Slide area are southwesterly 

winds from the north Pacific Ocean and Bering Sea. Serpentine Slide RNA is in the 

rain shadow of both the Alaska Range and the Yukon-Tanana uplands, and annual 

precipitation is relatively low. Annual precipitation at Central ranges between 15 and 

40 cm (mean 27.4 cm, sd 7.44) (fig. 18). Precipitation could be expected to be greater 

in the high elevations in the northern portion of the RNA because of orographic uplift; 

however, winter winds rearrange the snow pack (fig. 19) by removing snow from some 

sites and adding it to others, thereby making the actual moisture status highly local in 

the alpine zone of the RNA.

Most interior Alaska locations experience a gradual increase in monthly precipitation 

during the summer (monsoon) as large Pacific frontal systems replace local convective 

activity as the predominant source of moisture. The average precipitation for summer 

months at Central does not reflect the typical monsoonal pattern during the years of record (fig. 20). Locations northeast of the mountains of the Yukon-Tanana uplands, such 

as Central and Serpentine Slide, may experience a rain-shadow effect when moisture 

enters interior Alaska via southwesterly winds.
17
18

The RNA occurs on the edge of the Yukon Flats, the area with the warmest and driest 

summer climate in Alaska. Patric and Black (1968) calculated potential evapotranspiration and an index of aridity (potential evapotranspiration as a percentage of actual) for 

322 weather stations in Alaska. Fort Yukon and Chalkyitsik in the Yukon Flats north 

and east of the RNA had the greatest moisture deficits and highest indices of aridity 

of all stations in Alaska. The Beaver Creek lowlands extend north and east of Serpentine Slide and connect directly into the Yukon Flats. Steep, south-facing low-elevation 

bluffs in the RNA are especially hot and dry (fig. 21).

Near Serpentine Slide RNA, strong surface heating during the day, aided by terraininduced convection, produces small isolated convective cells. Rain showers from these 

cells often can be seen evaporating before they reach the ground at Serpentine Slide 

(fig. 22). Early summer weather in the area includes many warm, clear, sunny days (fig. 

23).

Vegetation patterns along the Beaver Creek flood plain indicate that the river’s flow is 

relatively well modulated. The predominance of coarse material and the scarcity of fine 

sediments in the flood plain indicate that the flow of Beaver Creek is relatively clear 

even during high water. An annual high water stage scours and reworks a zone covered 

by about a 1-m rise in the average summer level of the river. Fine sands, small gravels,

Hydrology
19

and some silts are characteristic of the annual scour zone. Irregular high water stages 

that reoccur over intervals longer than 1 year rework a zone about 2 m higher than 

the annual scour zone. The irregularly flooded zone is highly variable in width and 

marked by coarse sands and rounded, medium-sized gravels (fig. 24). Sloughs and 

channel cutoffs, especially those receiving input from streams draining steep slopes, 

contain a thin cap of fine silts or clay; humus is sometimes present from the buildup of 

lush stands of sedges.

The entire watersheds of two small streams, Flash Creek and Amy Dolomite Creek, 

are located in the northwest portion of the RNA (see fig. 5). Both watersheds extend 

into the high-elevation alpine zone. Late-season snow melt from high elevations is an 

important source of midsummer stream flow in Flash Creek. Winter stream flow also 

occurs in Flash Creek as indicated by the buildup of aufeis indicated along the lower 

few meters of the stream channel just above the Beaver Creek flood plain (fig. 25). 

Aufeis also augments late season stream flow as it melts. The stream channels of both 

creeks are normally dry at the end of summer (figs. 26 and 27).

Much of the stream flow reaching the flood plain of Beaver Creek in the RNA is captured by beaver dams (fig. 28). Small deltas of angular rock protrude into the beaver 

ponds from the mouths of the streams, indicating that the channels are subject to flash 

floods. Small springs and seep slopes are found along concave portions of the main 

slope that rises from Beaver Creek (figs. 29 and 30).
20
21
22

Juday (1987) describes the importance of geological features in Alaska RNA proposals 

by using Serpentine Slide RNA as an example. Scientific and educational values of the 

serpentinite exposure, the earthslide, and the juxtaposition of diverse bedrock types are 

all significant.

Bedrock geology-The portion of the WMNRA that includes Serpentine Slide is primarily within the Livengood terrane of Jones and others (1984), with minor amounts 

of the Manley terrane (Kandik Terrane of Churkin and others [1982]) and the Wickersham terrane (Beaver Terrane of Churkin and others [1982]). The composition and 

structural relation of bedrock units in the RNA and the surrounding area provide 

critical evidence for understanding the geologic history of an important and geologically complicated part of Alaska. Churkin and others (1982) interpret the existence of a 

complex of terranes in that portion of east-central Alaska surrounding Serpentine Slide 

as the result of tectonic delivery of microplates accreting to the North American plate. 

In their view, these terranes have formed elsewhere and moved together to account for 

the diversity of continental margin, island arc, and submarine rocks. Strike-slip faults 

mark the margins of terranes that collided obliquely, and thrust and other high-angle 

faults mark head-on collisions that now outline microterrane accretion zones.

Weber and others (1988) and Moore and Nokleberg (1988) identify problems with this 

interpretation, especially the lack of deformation and metamorphism in the Wickersham terrane and a lack of high-angle faulting in critical locations.

The surface geology of Serpentine Slide RNA is shown in figure 31. Quaternary alluvium in the RNA is restricted to the Beaver Creek corridor. The alluvium is mainly 

sand and granule- to boulder-sized, smooth, rounded gravel (fig. 32) up to 15 m thick; 

it is generally unfrozen (Weber and others 1988). The southern portion of the RNA 

includes small areas of loess and colluvium (unfrozen) over shallow bedrock. Even 

during Pleistocene glacial maxima, the Beaver Creek watershed was not extensively 

glaciated and glacial rock flour sources were relatively limited. Discharge of glacial meltwater placed large amounts of gravel into Beaver Creek headwater streams; 

meltwater also incised the the former flood-plain surface to form a prominent terrace 

above Beaver Creek (Weber and others 1988). Deep and extensive loess deposits are 

not found near Beaver Creek as is typical of populated lowelevation areas along the 

Tanana, Yukon, and other major braided rivers in interior Alaska.

Geology
23
24

The Wilbur Creek unit is a Jurassic or Cretaceous sequence, or both, exposed in the 

southeastern portion of the RNA. It is made up of polymictic conglomerate (5 percent), 

graywacke (20 percent), siltstone (25 percent), and shale (50 percent) (Weber and others 1988). Evidence of submarine deposition (ripple marks, laminations, scour channels) is abundant. An area tentatively mapped as the Cascaden Ridge unit forms the 

northwestern ridge perimeter (fig. 31) of the RNA. The Cascaden Ridge unit of Weber 

and others (1985) is of Middle Devonian age. The mapped unit in the RNA includes 

immature, locally derived clasts of Amy Creek dolomite and chert, greenstone, and 

other volcanic rock fragments in a sandy matrix, which strongly suggest deposition in 

a fault-block basin (Weber and others 1988).

The Amy Creek unit, assigned a late Proterozoic age, makes up much of the slope 

above Beaver Creek in the northern portion of the RNA (fig. 31). The Amy Creek unit 

contains a dolomite (magnesium carbonate) and a chert member. Along much of its 

southern contact, the Amy Creek Unit is overthrust by a mafic-ultramafic complex. 

The dolomite member is largely composed of dolomitic mudstone and packstone, often 

marked by narrow laminations in fine muds. Rubbly outcrops of dolomite are common, 

and extensive silicification of the dolomite is reported by Weber and others (1988). Results of soil analyses showed that limy inclusions also are found within the Amy Creek 

dolomite. The chert member is made up of a black massive chert and thin interbeds of 

carbonaceous argillite that grade upwards into dolostone lenses.

Two thrust faults occupy the central portion of the RNA, thereby indicating the complex geology of the area. The history and circumstances of faulting in the area are not 

fully understood yet.
25

The serpentinite outcrop in the RNA is part of a complex of greenstone and layered 

mafic-ultramafic rocks that are mapped as three units in figure 31. Weber and others 

(1988) report radiometric age dates for the belt containing the three rocks as 518-633 

million years old. A greenstone unit in the south-central portion of the RNA is a metabasalt. The other two units include layers of grayish-green, greenish-black, and black 

serpentinite derived from clinopyroxene, peridotite, and dunite; and layers of mafic 

rocks including clinopyroxene gabbro, microgabbro, and diorite (Weber and others 

1988). The serpentinite and mafic rocks occur in a belt along the ridge summit in the 

southwest portion of the RNA, where most of the unvegetated serpentinite exposures 

are located, and extend down the main slope in the center of the RNA to Beaver Creek.

The Wickersham unit is Cambrian to Precambrian in age and is quite diverse. The 

Wickersham unit includes a grit; graywacke grit; maroon, green, and gray argillite; 

and arenaceous limestone. Outcrops of the Wickersham unit occur on the upper ridge 

in the northeast portion of the RNA (fig. 31). Distinctive flat, friable reddish (maroon) 

rocks and green pebbles make up part of the bedload of Flash Creek (see fig. 5), indicating that at least those two members of the Wickersham unit are present in the area.

Serpentine geology—Serpentine forms from a magma of ultramafic composition; that 

is, a solution made almost entirely of iron and magnesium minerals (especially olivine) 

that lack calcium and silicon oxides. As the magma nears the surface, presumably in 

an area of thin crust at a seafloor spreading center, it becomes hydrated in the presence 

of near-surface water. Hydration alters the magma to serpentine (Gilluly and others 

1968). Looney and Himmelberg (1988) suggest that the serpentinite trend that includes 

the Beaver Creek area was emplaced as part of an ophiolite in the late Proterozoic to 

Cambrian, though not as a primary emplacement from the mantle but in a later event. 

They report that hornblende in gabbro and diorite dikes intruding serpentinite near 

Livengood (southeast of the RNA) is 518-633 million years old. Foster (1968) notes 

that a special feature of the Beaver Creek serpentinite is the presence of tectonic inclusions, especially rodingites (calcium silicate-rich rocks).

The minerals, principally olivine, that make up serpentine generally are poor clay 

formers. Serpentine outcrops often disintegrate into gravel, and this is the case in the 

RNA. The center of these outcrops is almost totally unvegetated.

Foster (1969) performed an element analysis of serpentine samples from the Beaver 

Creek serpentinite. Table 2 gives the results for the two stations closest to, but outside, 

the RNA. The samples contain high concentrations of siderophile elements, such as 

iron, chromium, nickel, and cobalt, that are characteristic of serpentine sites (Brooks 

1987). Much of the Beaver Creek serpentine outcrop can be considered high in nickel 

(Foster 1969). Calcium content of the samples is very low and magnesium content is 

high-classic indicators of poorly weathered serpentine bodies.

The mineral clevage in serpentine is usually along only one plane, and it fractures easily into conchoidal or splintery shapes. (it is a somewhat weak rock.) The head of the 

large and active earthslide is in the center of the main exposure of the mafic-ultramafic 

complex in the RNA (figs. 31 and 33).
26

Serpentinite, with small veinlets of asbestos, basalt, and shale are common in the 

earthslide.2 The slide appears on aerial photos taken in July 1951, although it probably 

covered a smaller area then. In a 1982 site visit, the slide appeared to have been recently active and enlarged. Evidence of this included trees with green leaves and intact 

root wads that had fallen into the slide along the top and sides, fresh gravel surfaces 

throughout the slide area with little colonizing of early successional vegetation, and 

deep tension cracks and fissures along the sides (fig. 34). A young forest zone along the 

north side of the slide appeared to have experienced 20 to 40 years of succession. By 

1987, plant cover had increased along the sides and at the head of the slide (fig. 35), but 

the floor and the deposition zone at the mouth of the slide had experienced additional 

transport of sediment and remained largely

2

 Chapman, Robert. 1983. Letter dated June 16 to Glenn Juday. 

On file with: G. Juday, University of Alaska Fairbanks, Agricultural Forestry Experiment Station, 309 O’Neill Building, 

Fairbanks, AK 99775.
27

unvegetated (see fig. 9). The debris piled up at the mouth of the slide has altered drainage patterns and created new ponds and wet ground; flows of debris have been great 

enough to knock down large mature white spruce trees and kill others through root 

suffocation (fig. 36).
28

No intensive soil surveys have been done in the RNA. The topography of Serpentine 

Slide includes rough, mountainous terrain and high terraces and the flood plain of Beaver Creek. Areas of serpentinite and bedrock knobs at the highest elevations exhibit 

poor soil development. Mass wasting processes cause talus to accumulate at the base of 

erosion-resistant features. Soils in talus materials are Lithic Cryorthents derived from 

serpentine, basalt, or metabasalt. They are very gravelly, well drained, and shallow 

over bedrock and may be frozen at the base, although they are not ice-rich.

The soils of valley bottoms and terraces occur over well-sorted alluvium with an abundant coarse fraction. These soils are alternating areas of well-drained, permafrost-free 

Cryorthepts and poorly drained permafrost-dominated Pergelic Cryaquepts. Material 

recently deposited by Beaver Creek is initially free of permafrost. Coarse-textured 

soils on well-drained sites generally remain free of permafrost. Poorly-drained sites 

that develop a thick humic layer generally develop permafrost with time. Steep southfacing lower slopes include areas of Typic Cryochrepts or even Mollisols under grassy 

vegetation with abundant coarse fraction. Limited areas of deeper silty deposits on 

south-facing toe slopes and benches are Loamy Aeric Cryaquepts.

Brooks (1987) describes the challenges confronting plants growing on serpentine sites 

that are not intensively weathered in humid tropical zones.

1. High siderophile (toxic heavy metal) content.

2. Low concentration of major plant nutrients such as nitrogen, phosphorus, and potassium.

3. Low calcium and high magnesium levels.

4. Low clay content, and the clays that are present have low exchange capacity.

Table 3 shows the properties of two high-elevation soils from Serpentine Slide. One 

soil was collected on barren serpentine at 730 m elevation in section 17 of T. 10 N., R. 

1 W. (figs. 5 and 8), and the other from a treeline site at similar elevation and aspect 1 

km east. The extreme amount of magnesium, low levels of calcium and nitrogen, and 

general lack of clays in the serpentine soil are obvious. Figure 37 shows the textural 

content of the two soils. The serpentine soil has practically no vegetation cover and 

consists mainly of coarse gravel (fig. 38). The treeline site is well vegetated and has a 

well-developed litter and humus layer at the surface (fig. 39). Two physical characteristics of serpentine soils that are important for vegetation are excellent aeration through 

porous gravels and extreme fluctuations in surface temperature through rapid radiant 

energy loss and gain (Brooks 1987).

Table 4 gives the properties of two low-elevation soils from the RNA. The Limestone 

Bluff soil at the base of the south-facing slope on the western edge of the RNA represents a limy phase of the Amy Creek dolomite. The Bluff Flats soil is from a forest plot 

on a high terrace above Beaver Creek where the creek leaves the eastern edge of the 

RNA. Figure 40 shows the texture of the two soils. Bluff Flats is an alluvial sand on 

a probable Pleistocene terrace with a small amount of silt and clay from a thin cap or 

upper layer. The Bluff Flats soil includes an epipedon of 2 to 5 cm that probably represents deposition from a maximum Holocene flood.

 
29
30
31

The Limestone Bluff soil is predominately silt with a substantial clay fraction; over 

half the Limestone Bluff sample consisted of coarse angular fragments (table 4). The 

Limestone Bluff soil has a high pH and large cation exchange capacity due to the high 

calcium content typical of limestone soils. The elevated magnesium level and high 

levels of phosphorus, potassium, and organic matter provide the basis for high productivity despite soil moisture limitation.

The Bluff Flats soil contains no coarse material and, although slightly acidic, has 

a high pH for the understory of a mature white spruce forest. The moderately high 

calcium content responsible for this high pH results from the input of either local limy 

beds or Tolovana Limestone from the headwaters of Beaver Creek.

Flora—Table 5 is a list of 124 vascular plants collected or observed in Serpentine 

Slide RNA or collected nearby; 35 are common, widespread species whose presence 

was noted in the field. Voucher specimens are available at the University of Alaska 

Herbarium for 55 low- and mid-elevation species and 5 species collected on highelevation serpentine. The Norwegian botanist Gjaerevoll (1958, 1963, 1967) made extensive plant collections in the White. Mountains. His collections were concentrated on 

limestone habitats near Limestone Jags RNA (Juday 1989) 16 km south of Serpentine 

Slide. Only 29 species reported by Gjaerevoll are listed in table 5-the ones collected in 

habitats similar to those in Serpentine Slide or along the Beaver Creek flood plain near 

the RNA.

Three plants collected in the RNA, Carex eburnea, Artemisia alaskana, and Agropyron spicatum, are from areas beyond the distribution limits in Alaska given by Hulten 

(1968). All three species were collected on a steep south-facing slope near the Limestone Bluff soil sample location. Carex eburnea is a sedge of dry sand or rocky sites, 

usually is in calcareous soil, and is known primarily from the Tanana River drainage 

(Hulten 1968). The Serpentine Slide locality is a northward range extension; it is the 

first report of the species north of the Yukon-Tanana uplands in Alaska.

Artemisia alaskana is a sagebrush widely distributed in upland interior and northern 

Alaska, including much of the Brooks Range. Hulten (1968) indicates a distribution 

gap for this species across the extensive Yukon Flats and nearby lowlands, and Gjaerevoll (1967) did not collect it in the interior mountains. The Serpentine Slide collection 

indicates that Artemisia alaskana is found on suitable habitats in at least a portion of 

the gap.

Agropyron spicatum was collected on a very shallow stony soil over Amy Creek chert 

(see fig. 31) just above the Beaver Creek flood plain (see fig. 22). This species is a dominant grass over much of the sagebrush steppe region of eastern Oregon and Washington. Hult6n (1968) depicts the species in Alaska as restricted to a corridor along the 

Tanana River and the upper Yukon River in the Yukon Territory. The Serpentine Slide 

collection is an extension of the known range of the species north across the Yukon-Tanana uplands and represents one of the northernmost localities reported.

Biota

Vegetation
32

Table 5-Vascular plants collected or observed in Serpentine Slide Research 

Natural Area or the immediate vicinitya

Species Habitat or collection notes

Aconitum delphinifolium DC. Widespread species in meadows and forest openingsb

Agropyron spicatum (Pursh)

 Scribn. & Sm. Steep south-facing bluffs above Beaver Creekc

Agropyron subsecundum (Link)

 Hitchc. Along Beaver Creekd

Alopecurus aequalis Sobol. Upper elevation of Beaver Creek flood plainc

Artemisia furcata Bieb. Dry rocky slopese

Arctagrostis latifolia (R. Br.) Griseb. Meadows and sandbars along Beaver Creekb

Arctophila fulva (Trin.) Anderss. Wet permafrost ground, edge of ponds on flood plainc

Arctostaphylos uva-ursi (L.) Spreng. Restricted to dry bluffs and aspen forest understoryb

Arnica alpina (L.) Olin Alpine and subalpine openingsb

Artemisia alaskana Rydb. Dry gravel bars and rocky south bluffc

Artemisia frigida Willd. Steep south bluffs on unstable skreeb

Astragalus alpinus L. Meadows at forest edge and openings on slopesc

Betula glandulosa Michx. Dominant alpine tundra speciesb

Betula papyrifera Marsh. Common forest tree on slopesb

Boschniakia rossica (Cham. &

Schlecht.) Fedtsch. Parasite on roots of alder, in flood-plain forest plotc

Bromus pumpellianus Scribn. Dry sandy soils on warm south slopesc

Bupleurum triradiatum Adams Species most tolerant of serpentineb

Calamagrostis lapponica (Wahlenb.)

 Hartm. Cache Mountaind

Calamagrostis purpurascens R. Br. Forest edge and openings on slopesc

Callitriche verna L. In mud at edge of beaver pondc

Campanula aurita Greene Rocky habitats on low-elevation slopesc

Cardamine pratensis L. Shores of beaver ponds, streams, and river flood plainc

Carex aquatilis Wahlenb. Sloughs on Beaver Creek flood plainc

Carex chordorrhiza Ehrh. Beaver Creekd

Carex eburnea Boott Dry south bluffs at edge of Beaver Creek flood plainc

Carex eleusinoides Turcz. Old slough channels on Beaver Creek-flood plainc

Carex rostrata Stokes Wet sites on Beaver Creek flood-plainc

Carex saxatilis L. Wet sites on Beaver Creek flood plainc

Carex vaginata Tausch Wet forest understory on Beaver Creek flood plainc

Cassiope tetragona (L.) D. Don Shaded snow collectiond areas, high and low elevationsc

Chamaedaphne calyculata (L.) Moench Beaver Creek lowlandsd

Cicuta mackenzieana Raup Beaver Creek lowlandsd

Cnidium cnidiifolium (Turcz) Schischk. Open, dry south bluff meadowsb

Crepis elegans Hook On river gravel of Beaver Creekc

Cystopteris fragilis (L.) Bernh. Chert-limestone-dolomite rock crevice near flood plainc

Drosera rotundifolia L. Beaver Creek forest at Sheep Creekd

Dryas octopetala L. Calcareous substrates from low to high elevationb

Elymus innovatus Beal Open, dry south bluff meadowsb

Empetrum nigrum L. Permafrost ground on old flood-plain terracesb

Epilobium anagallidifolium Lam. Cache Mountaind

Epilobium homemannii Rchb. Cache Mountaind

Epilobium latifolium L. Colonizer of gravely Beaver Creek flood plainc

Equisetum palustre L. On Beaver Creekd

Equisetum silvaticum L. Cache Mountaind

Erigeron elatus Greene Low-elevation meadows and forest edgec

Erigeron hyperboreus Greene High elevations, edge of serpentinee

Erigeron purpuratus Greene Open gravelly flood plain of Beaver Creekc

Eriophorum vaginatum L. Wet permafrost sites on Beaver Creek lowlandsc

Festuca altaica Trin. Rocky meadows and forest understoryc

Galium boreale L. Aspen and spruce-birch forest understoryc

See footnotes on page 34.
33

Table 5 Vascular plants collected or observed in Serpentine Slide Research

Natural Area or the immediate vicinitya (continued)

Species Habitat or collection notes

Galium trifidum L. Moist meadows and forest understoryb

Gentiana glauca Pall. Cache Mountaind

Geocaulon lividum (Richards.) Fern. Aspen forest understoryb

Gymnocarpium dryopteris (L.) Newm. Moist forest sitesc

Hedysarum alpinum L. Rocky sites in white spruce and on flood plainc

Hippuris vulgaris L. Aquatic species in beaver pondc

Juncus filiformis L. Beaver Creekd

Juniperus communis L. Steep unstable skree on south bluffsb

Lagotis glauca Gaertn. Open gravelly tree line and alpine tundrae

Ledum decumbens (Ait.) Small Permafrost at low and high elevationsb

Ledum palustre L. Permafrost at low and high elevationsb

Linnaea borealis L. Moist spruce forest understory, low to mid elevationb

Lloydia serotina (L.) Rchb. Open limestone-dolomite south bluff meadowsc

Lupinus arcticus S. Wats. Widespread in foyst openingsc

Luzula arcuata (Wahlenb.) Sw. Cache Mountaind

Lycopodium alpinum L. Cache Mountaind

Lycopodium clavatum L. Cache Mountaind

Lycopodium complanatum L. Forest openings with thin soil over bedrockc

Lycopodium selago L. Widespread on thin soils, low to high elevationsc

Mertensia paniculata (Ait.) G. Don Widespread in forest understoryb

Minuartia arctica (Stev.) Aschers. &

 Graebn. Collected on serpentinee

Moneses uniflora (L.) Gray Beaver Creek flood-plain mature forest understoryb

Myriophyllum spicatum L. Submerged aquatic spedries in beaver pondsc

Oxycoccus microcarpus Turcz. Beaver Creek lowlandsd

Papaver macounii Greene Open limestone-dolomite south bluff meadowsc

Pedicularis labradorica Wirsing Beaver Creek lowlandsd

Pedicularis verticillata L. Meadows with thin soilc

Picea glauca (Moench) Voss Dominant late successional treeb

Platanthera obtusata (Pursh) Lindl. Mature white spruce bottomland forest understoryb

Poa glauca M. Vahl Dry sandy sites at low elevationsc

Polemonium acutiflorum Willd. Meadows near BeaverCreekc

Polygonum alaskanum (Small) Wight Bottom-land cforest and edge on Beaver Creek

 flood plainc

Polygonum viviparum L. South bluff meadowsc

Populus balsamifera L. Flood plain and upland seep slopesb

Populus tremuloides L. Dominant tree on driest south slopesb

Potamogeton alpinus Balb. Lake between Sheep and Mascot Creeksd

Potamogeton berchtoldi Fieb. Lake between Sheep and Mascot Creeksd

Potamogeton filiformis Pers. Aquatic species in beaver pondc

Potamogeton perfoliatus L. Lake between Sheep and Mascot Creeksd

Potentilla fruticosa L. Forest edge and openingsb

Potenfilla hookeriana Lehm. Low-elevation south-facing gluffsb

Pulsatilla patens (L.) Mill. Treeless south-facing buffsb

Pyrola asarifolia Michx. Beaver Creek lowlandsd

Pyrola minor L. Cache Mountaind

Rosa acicularis Lindl. Forest understory species of dry sitesb

Rubus arcticus L. Moist meadows near creeksc

Rumex acetosa L. ssp. alpestris

 (Scop.) Love Collected on poorly vegetated serpentinee

Salix alaxensis (Anderss.) Cov. Found on Beaver Creek flood plainb

Salix hastata L. Occurs on gravelly flood Slainc

Salix niphoclada Rydb. Beaver Creek flood plainb

See footnootes on page 34.
34

Table 5-Vascular plants collected or observed in Serpentine Slide Research

Natural Area or the immediate vicinitya (continued)

 Species Habitat or collection notes

Saxifraga bronchialis L. Lion Peakd

Saxifraga flagellaris Willd. Lion Peakd

Saxifraga nivalis L. Lion Peakd

Saxifraga reflexa Hook. On serpentine, collected near Livengood on

 serpentineb

Saxifraga tricuspidata Rottb. Limestone and dolomite rocks and skreeb

Senecio atropurpureus (Ledeb.)

 Fedtsch. Lion Peakd

Senecio conterminus Greenm. South slope meadows with thin soilsc

Shepherdia canadensis (L.) Nutt. In dry aspen forestsb

Silene repens Patrin Rocky meadows

Solidago multiradiata Ait. Forest edge and openingsc

Sparganium hyperboreum Laest. Aquatic species in beaver pondc

Stellaria crassifolia Ehrh. Beaver Creekd

Stellaria edwardsii R. Br. Found on high-elevation rocky skreec

Thalictrum sparsiflorum Turcz. Moist meadowsc

Trientalis europaea L. Beaver Creek lowland forestd

Trisetum spicatum (L.) Richter Tundra and forest openingsc

Vaccinium uliginosurn L. Primarily in muskegs

Valeriana capitata Pall. Moist meadows and forest edge near streamsc

Viburnum edule (Michx.) Rat. Widespread in forest understoryb

Viola biflora L. Occurs on skree slopesc

Viola epipsila Ledeb. Cache Mountaind

Wilhelmsia physodes (Fisch.) McNeill High gravel bars of Beaver Creek flood plainc

Woodsia glabella R. Br. Found in crevices in limestone

Zygadenus elegans Pursh Dry, treeless south-facing slopesc

a

 Nomenclature follows Hult6n (1968).

b Observed and noted in the field by Glenn Juday.

c Collected by Glenn Juday; voucher specimen in University of Alaska Fairbanks Herbarium. 

d Collected by Olav Gjaerevoll in habitats similar to those in Serpentine Slide RNA in the localities noted. Locality 

rendered as “Lion Peak” in Gjaerevoll (1958, 1963, 1967) probably represents mispronunciation of “Lime Peak,” 30 

km east southeast of Serpentine Slide RNA. 

e Collected by David Murray; voucher specimen in University of Alaska Fairbanks Herbarium.

The plant species richness of Serpentine Slide RNA is due to the presence of both 

typical habitats containing generalist species and special habitats having species with 

restricted distributions. The RNA includes frequently disturbed flood plain with poorly 

vegetated gravel bars, serpentinite, dolomite, limestone, oversteepened river bluffs, 

beaver ponds and meadows, alpine tundra, bottom-land forests and shrublands, black 

spruce (Picea mariana (Mill.) B.S.P.) permafrost, and upland birch (Betula sp.), white 

spruce, and aspen (Populus sp.) forest. Only limited plant collections have been made 

in the high elevations of the RNA, in mid-elevation forests and during early springtime.

Several submerged aquatic plant species are found in beaver ponds in the RNA, despite 

sudden and dramatic changes in water levels and the appearance and disappearance of 

ponds as beavers construct new dams and abandon old ones. Dominant species in the 

pond depicted in figure 13 are Myriophyllum spicatum, Sparganium hyperboreum, and 

Potamogeton filiformis with Callitriche verna common around the shallow margins 

and in shoreline mud. Sparganium hyperboreum is known to intergrade with S. minimum (Hartm.) Fries across much of central Alaska, although Harms (1973) considers 
35

the two taxa distinct. Many of these aquatic species have propagules that are dispersed 

by migrating waterfowl; this accounts for the ability of the plants to rapidly colonize 

ephemeral beaver ponds.

Pyrola asarifolia (fig. 41) and Platanthera obtusata (fig. 42) are species of the mossy 

understory of mature white spruce forests. Lycopodium complanatum (fig. 43) is a species typical of dry forests and low-elevation rocky sites.
36

Serpentine vegetation—Studies of the effect of serpentine soils on vegetation have 

provided useful insights on plant evolution, ecology, systematics, and physiology 

(Brooks 1987, Krukeberg 1954). Brooks (1987) states, “...we are hardly any closer today to solving or explaining the serpentine factor, than we were 50 years ago. Although 

the evidence is still confusing and contradictory, a degree of consensus is starting to 

emerge as to some aspects of the problem. The first of these is that no single factor is 

responsible for the infertility of serpentine soils but rather...a combination of factors.”

The most important serpentine factors demonstrated to date are toxic effects of high 

nickel content, toxic effects of high levels of magnesium in the absence of calcium, 

high pH values that affect the availability of nutrients, and the physical stresses of 

poorly vegetated, high radiatiative environments (Brooks 1987). These distinctive 

serpentine conditions subject colonizing plants from adjacent nonserpentine habitats 

to very strong natural selection, thereby causing local adaptation that in time proceeds 

from ecotype to variety to species.

On serpentine sites in midlatitude and tropical regions, species have evolved that are 

restricted to serpentine (serpentine endemics), many regionally common species are 

excluded from serpentine, and some species that are habitat specific or restricted in 

some other way on “normal” sites are released from competitive exclusion on serpentine (Brooks 1987). Kruckeberg (1984) reports that 215 species, subspecies, and varieties of native California plants are restricted completely or in part to serpentine sites. 

No serpentine endemic species have been identified in Alaska, however. The pattern 

of serpentine plant geography and evolution is different in glaciated regions and areas 

with stressful climates than in areas closer to the equator.

Whittaker (1960) documents a large decrease in the number of serpentine-tolerant species from the coastal maritime to the continental climate regions of southwest Oregon, 

one of the largest exposures of serpentine rock in the world. The number of serpentine 

endemics decreases dramatically on serpentine exposures north of southwest Oregon. 

In central and northwest Washington and in British Columbia, Kruckeberg (1969) 

found that (1) serpentine vegetation assumes a typical alpine character; (2) some plants, 

including whole genera, are excluded from serpentine; (3) one species and two varieties of fern are faithful indicators of serpentine; and (4) only three flowering plant 

species are serpentine endemics, all from the Wenatchee Mountains of central Washington.

Brooks (1987) identifies a worldwide pattern in which serpentine endemics at the species level generally do not occur in areas covered by the maximum extent of glaciation, 

especially the Wisconsinan glacial maximum of 12,000 to 14,000 years ago. He interprets the absence of endemics in glaciated areas as the result of repeated extinction of 

locally adapted serpentine genotypes during glacial advances. Although Serpentine 

Slide was not covered by ice during glacial maxima, it did experience a harsh periglacial climate that eliminated most species, an environment comparable today only to 

polar desert regions of the high Arctic or Antarctic. Thus, even though local adaptation of plants to serpentine was eliminated in the geologically recent past, evolution is 

underway and a low level of adaptation could be expected to exist now.
37

Plant species richness is extremely low on serpentine outcrops in the western portion 

of the RNA. The two species with the greatest tolerance of serpentine conditions in 

the RNA are Bupleurum triradiatum (fig. 44) and Minuartia arctica (fig. 45). Rumex 

acetosa also is found in open serpentine habitat. A small specimen of Bupleurum was 

the only vascular plant growing in the vicinity of the serpentine soil sample (table 3). 

The central portions of the serpentinite barrens lack all vascular plant cover, although 

an orange crustose lichen is present (see fig. 38).

A few species occupy the partially vegetated edge of serpentine exposures in the RNA. 

Erigeron hyperboreus (table 5) is found on these edges, although it occurs mainly in 

the Brooks Range, with a few outliers. The White Mountains specimen of E. hyperboreus by Gjaerevoll (1967) is one of the only central Alaska collections. Saxifraga 

reflexa, a saxifrage of relatively dry sites, was observed on serpentine edge habitat in 

the RNA and was collected on serpentine in the Tolovana River area 40 km west of the 

RNA. Two other species collected in the upper elevations of the RNA, Artemisia furcata and Lagotis glauca, may not be related to serpentine. Artemisia furcata is a sage 

of sandy and rocky slopes, irregularly distributed across Alaska and Siberia. Lagotis 

glauca is a species of stony slopes in mountain tundra.
38

Very little published information is available on the flora of serpentine areas in central 

Alaska. Shacklette (1966) investigated a south-bluff plant community on greenstone 

near Eagle, Alaska, along the Yukon River near the Alaska-Yukon Territory border and 

concludes that “soils derived from this greenstone and from serpentine probably do not 

differ greatly in their content of elements, and this Eagle Bluff soil has, in general, the 

chemical nature of `serpentine soil’ as the term is used in ecological literature.” His 

soil element analysis data show, however, that the Eagle Bluff soil is not as enriched in 

nickel and chromium as the soil at Serpentine Slide, contains one-tenth the cobalt, and 

has normal to slightly enriched amounts of calcium compared to the severe calcium deficiency at Serpentine Slide (tables 2 and 3). The two soils are similar in their physical 

characteristics and pH, and Eagle Bluff is somewhat enriched in siderophile elements 

and magnesium. Some serpentine effects could be expected at Eagle Bluff, but not to 

the same degree as at Serpentine Slide. Batten and others (1979) note the high calcium 

content of soil at Eagle Bluff and do not report perceptible greenstone effects on vegetation.

Shacklette (1966) names the greenstone community at Eagle Bluffs a Bupleurum 

triradiatum-Zygadenus elegans association. Bupleurum triradiatum is clearly dominant on the most stressful sites at both Eagle Bluff and the RNA, but Z. elegans is not 

prominent in the serpentinite barrens of the RNA. The difference in elevation between 

the sites may be partly responsible for the absence of Z. elegans. The Eagle Bluff site 

extends from about 300 to 550 m; the serpentinite barrens in the RNA are mostly 

above 600 m. Bupleurum triradiatum grows in meadows and stony slopes from high 

elevations to low; Z. elegans is more common on warm south-bluff sites.

Shacklette (1966) lists three other high-constancy and high-fidelity species in the 

Bupleurum triradiatum-Zygadenus elegans association on “mafic and ultramafic rock 

outcrops in the Yukon-Tanana uplands”: Calamagrostis purpurascens, Juniperus communis, and Minuartia yukonensis Hult. The first two are present at Serpentine Slide 

(table 5) and prominent in low-elevation sites on or near the edge of serpentinite. Two 

other character species of Shacklette’s association prominent at Serpentine Slide are 

Saxifraga reflexa at high elevations and Galium boreale at low and midslope sites. A 

Rosa acicularis understory in a white spruce-paper birch forest type also is common to 

both sites (Batten and others 1979).

Dearden (1979) studied the flora of serpentine sites in Newfoundland. Three species 

that are dominants in his “arctic-alpine” serpentine community, Potentilla fruticosa, 

Juniperus communis, and Vaccinium uliginosum, are found in Serpentine Slide. Several other Newfoundland serpentine species, such as Androsace septentrionalis L., 

Cerastium beeringianum Cham. & Schlecht., Diapensia lapponica L., Rhododendron 

lapponicum (L.) Wahlenb., Salix arctica Pall., Saxifraga oppositifolia L., and Silene 

acaulis L., are distributed across portions of Alaska that include the RNA. The serpentine vegetation of Scandinavia is similar to that of the RNA. In Sweden (Rune 1953), 

there are no serpentine endemics at the species level, but a few serpentine subspecies 

or varieties have been identified. More common is the disjunct occurrence of arctic 

species in southern portions of the country on serpentine. Characteristic Swedish 

serpentine species known to occur or that may occur in the RNA are Campanula 

rotundifolia L., Minuartia rubella (Wahlenb.) Graebn., Rumex acetosa, Saxifraga oppositifolia, and Silene acaulis. Rocky serpentine barrens in Finland include only a few 

lichens and the moss Racomitrium lanugibosum; open gravelly sites in Finland have 

a few serpentine specialists such as Asplenium viride Hudson, Cerastium alpinum L., 

and Minuartia biflora among others (Brooks 1987).
39

Plant communities—Figure 46 is a vegetation cover map of Serpentine Slide RNA. 

The predominant vegetation cover is upland mixed white spruce and hardwood forest. 

About 38 percent of the RNA is mapped as spruce-birch forest, primarily located on 

greenstone, mafic rocks, and serpentinite (fig. 31) on upper elevation and midelevation 

slopes in the southern portion of the RNA and in the Wickersham unit in the northern 

portion (figs. 30, 33, and 47). The spruce-birch map unit contains small inclusions of 

nearly pure white spruce cover. A complete reconnaissance survey of plant community types is not available, but areas of the Picea glaucal/Linnaea borealis-Equisetum 

silvaticum community (table 1) occur within this forest type.

Birch forest with a minor component of white spruce occupies an additional 6.8 

percent of the RNA in the same area. Birch dominance increases above 600 m on 

the south-facing slope in the southern portion of the RNA. Spruce-aspen forest covers about 16 percent of the RNA, especially on Amy Creek dolomite (fig. 31) in the 

northern portion of the RNA below the spruce-birch forest belt (fig. 48). The internal 

drainage of dolomite and limestone may be partially responsible for droughty aspects 

of this forest type such as narrow tree crowns, wide tree spacing, and the presence 

of dry-site indicators such as lichen mats and Shepherdia canadensis (fig. 49). Amy 

Creek chert and dolomite outcrops also are associated with an especially open form of 

white spruce and aspen that has been labeled “woodland” on figure 46. Total canopy 

coverage in this type has not been measured, but oblique and vertical aerial photographs indicate it is close to the 25-percent threshold for woodland formations.

Black spruce woodland covers only about 8.6 percent of the RNA, considerably less 

than the average of the regional landscape in which Serpentine Slide is located. Black 

spruce plant community types are consistently found in topographic locations with 

little direct sunlight, including north-facing slopes and areas where low-angle sunlight 

is intercepted by intervening slopes (fig. 50). Several plant community types, most 

with high sphagnum moss dominance, are present (table 1) in the black spruce cover 

type.

Mature white spruce bottom-land forest is relatively restricted in extent in both Serpentine Slide RNA (2.9 percent of the area) and the Beaver Creek riparian corridor; 

most stands (fig. 51) are on the north and west banks of the river where they escape 

shading effects from the lowermost valley wall to the south (fig. 32). The most common white spruce bottom-land types are white spruce/Rosa acicularis and white 

spruce/feathermoss (fig. 42). Upland white spruce forest is more extensive; it covers 

6.7 percent of the RNA. The main area of white spruce upland forest is nearly coincident with the Wilber Creek unit in the southeast portion of the RNA (figs. 31 and 46).

Shrub-dominated vegetation covers a combined 4 percent of Serpentine Slide RNA. 

A tree line shrub belt and shrub tundra make up most of the shrub-dominated types; 

riparian shrubs mainly occupy a drainage down the center of the RNA (fig. 46). Areas 

mapped as balsam poplar forest along the Beaver Creek flood plain contain extensive 

stands of emergent poplar trees that currently share dominance with alder shrubs. 

Within the balsam poplar type narrow stands of willow shrubs are parallel to Beaver 

Creek. Only limited willow shrub stands occur in the RNA. Willows are more common along the Beaver Creek flood plain outside the RNA where they provide a corridor of habitat important to several wildlife species.
40
41
42

About 3 percent of the RNA is alpine tundra, generally at elevations above 800 m 

(figs. 5 and 46). South-bluff grasslands occupy about 17 ha or 1 percent of the RNA on 

oversteepened toe slopes at the topographic break along the Beaver Creek flood plain. 

Serpentinite barrens cover 4.6 percent of the RNA and are mostly at higher elevations 

in the western portion of the area.
43

Table 6 presents data from two white spruce forest reference plots. The Bluff Flats plot 

(fig. 5) is in the Beaver Creek bottom-land and the Spring Slope plot (fig. 5) is on the 

south slope above the river about 100 m below the local tree line (Juday 1984a). Both 

plots were marked to allow relocation; maps of tree stems, shrubs, logs, and river or 

stream position were produced as part of the RNA site documentation and are available from the Bureau of Land Management District Office in Fairbanks. The Spring 

Slope plot is in a natural catchment near a steep headwall (see fig. 30). Slope drainage 

is funneled down the slope; at times it spills over the natural channel of a stream 15 

m from the plot and deposits new soils. Soil moisture in the plot is augmented from 

springs, seeps, and subsurface flow. Trees are competing intensely for light, thereby 

achieving good form. Alders (Alnus spp.) enrich the nitrogen pool of the ecosystem 

and have regenerated in natural overstory mortality patches. The Bluff Flats plot is 

next to Beaver Creek in the northeast portion of the RNA on a high terrace (fig. 51). 

The Bluff Flats soil sample was collected on the boundary between 1/16-ha segments 

of the plot.
44

The bottom-land Bluff Flats forest plot contains larger white spruce trees than the 

Spring Slope plot, although average diameters and stand basal areas are comparable. 

Tree density in both bottom-land plot segments is typical of maturing undisturbed forest. The lower tree density in Bluff Flats segment 120 is associated with larger average 

and maximum diameters at breast height (d.b.h.). The bottom-land stand has remnant balsam poplar trees from an earlier successional stage, but they are considerably 

smaller at maturity than are typical balsam poplar along braided glacial river systems. 

Alder shrubs are an important component of both stands.

Table 7 shows the age and height characteristics of dominant white spruce trees in 

the two forest plots. The Bluff Flats plot is dominated by 125- to 150-year-old white 

spruce, which is consistent with the interpretation of this bottom-land forest as a 

maturing spruce stand in the last stages of replacing an earlier balsam poplar successional stage (fig. 52). Dominant white spruce in the bottom-land plot are about 3 to 5 

m shorter than trees of similar age on the Tanana River flood plain (Juday and Zasada 

1985). White spruce in the Spring Slope plot are considerably shorter, and their crown 

structure indicates that they are fully mature and unlikely to achieve further height 

growth. Height at maturity can be taken as an approximation of site productivity. Juday 

(1984a) notes that the Spring Slope plot occurs at an unusually high elevation in eastcentral Alaska for such a large and well-developed stand; he attributes the high productivity to subirrigation by seepage (fig. 29), the unbroken south-facing slope, and the 

sheltered nature of the topography.

Figure 53 shows the d.b.h. size class distribution of white spruce in the two stands. The 

bottom-land plots (combined) contain fewer small trees and trees in larger size classes 

than the Spring Slope plot does, thereby reflecting the greater competition and productivity of the bottom-land environment.

Figure 54 shows one of two 10- by 50-m tree-line transects in section 9, T. 10 N., R. 1 

W. Figures 55 and 56 show the position, height, and basal diameter of all woody stems 

1 cm or greater in the transects. Table 8 summarizes the structure of woody vegetation 

in the transects. In transect 1, white spruce has the largest, although the most variable, 

mean diameter; alder is the tallest woody vegetation. In transect 2, alder is absent and 

hybrid birch is the largest woody vegetation; white spruce are short and small in diameter. The average stem characteristics suggest that transect 1 represents an alder shrub 

transition between forest and alpine tundra in which an early wave of spruce is emerging and recruitment of white spruce has continued in recent years. Birch stems are a 

hybrid of the tree and dwarf tundra species that have escaped natural pruning and are 

enlarging after years of suppression. Transect 2 is a patch of dwarf birch tundra where 

white spruce have recently become established.

Table 9 shows the average stand structural characteristics of woody vegetation in the 

transects. Transect 1 supported a projected 260 stems/ha of white spruce, but transect 

2 had nearly three times as many. Transect 1 contained over five times the woody 

basal area of transect 2. These characteristics are consistent with an earlier and better 

established wave of spruce in transect 1 and a more recent, slow tree line advance in 

transect 2.
45
46
47
48
49

Serpentine Slide contains a wide variety of wildlife habitats across many elevations. 

The pristine character of the surrounding wilderness landscape provides high-quality 

habitat and unimpeded movement into and out of the area. Animals that are particularly characteristic of the area, species sensitive to human activities or disturbance, 

and species that have important ecological roles are included on the RNA type needs 

list (table 1).

Fish—The Bureau of Land Management (1984) reports the following information on 

fish in Beaver Creek. 3 Fish species in Beaver Creek include arctic grayling (Thymallus arcticus), broad whitefish (Coregonus nasus), burbot (Lota lota), longnose sucker 

(Catostomus catostomus), northern pike (Esox lucius), round whitefish (Prosopium 

cylindraceum), and slimy sculpin (Cottus cognatus). A sheefish or inconnu (Stenodus 

leucichthys) was collected in upper Beaver Creek, although it is an anomalous species for the stream. A fall run of chum salmon (Oncorhynchus keta) was reported in 

September 1982. Fish habitat is in good condition and undisturbed except for periodic 

sediment discharge from placer mining on Nome Creek, an upper tributary of Beaver 

Creek.

Amphibian—The northern wood frog (Rana sylvatica) (see footnote 3) is the most 

widely distributed reptile or amphibian in Alaska and is found throughout most of the 

State south of the Brooks Range (Hodge 1981). Wood frogs live in various habitats 

away from water but require ponds for breeding (the eggs are fertilized externally); 

egg masses are attached to submerged aquatic vegetation rather than deposited at 

the surface, to prevent damage from rapid changes in temperature (Broderson 1982). 

Northern wood frogs in Alaska take advantage of any warmth in their environment 

and become active quickly (Hodge 1981). Figure 57 shows a northern wood frog at 

the edge of the beaver pond shown in figure 13. Frogs were abundant and easily seen 

in 1987 and 1988 along the grassy edges of beaver ponds in the RNA, and some are 

particularly large (fig. 58). The shallow water and warm summer climate of the RNA 

provide ideal conditions for the rapid growth and maturation of frogs, which is critical 

to their survival at the northern margin of their range.

3

 Taxonomic nomenclature follows USDA Forest Service (1979).

Fauna
50

Birds—A comprehensive field effort to document all birds in Serpentine Slide was not 

made. Several species have been seen in the RNA and many others have predictable 

habitat relations (Kessel 1979) so that their presence can be inferred with great confidence. Table 10 lists 117 birds known to occur or that may occur in Serpentine Slide 

RNA.

The complex of habitats created by Beaver Creek in its flood plain and riparian corridor adds greatly to the wildlife species richness of the RNA. River gravel bars adjacent 

to Beaver Creek are an important shore-bird habitat. The semipalmated plover is a 

common nesting bird in Alaska in habitats including gravelly shorelines of large rivers 

and lakeshores in the interior of the State (Armstrong 1983, Gabrielson and Lincoln 

1959). The semipalmated plover is a conspicuous summer resident of the annual and irregular flood zone of Beaver Creek in the RNA (fig. 59). Plovers generally scrape out a 

depression in sand or gravel for a nest and lay eggs that are buff in color and mottled to 

match sand or gravel. When a large animal (such as a person) approaches a plover nest, 

the adults characteristically behave as if injured and try to draw the animal away. This 

behavior can be observed repeatedly by any visitor walking along Beaver Creek in 

the summer. Semipalmated plovers largely consume small animals, especially insects 

and aquatic and marine creatures (Matthews 1983). Spotted sandpipers also were seen 

along Beaver Creek.

Breeding pairs of lesser yellowlegs were seen along Beaver Creek, and yellowleg tracks 

are one of the most common markings in soft sediments in the river’s flood zone. Yellowlegs eat small fish and aquatic invertebrates, such as water boatmen, diving beetles, 

dragonfly nymphs, and flies, and often nest in black spruce muskegs (see fig. 32) 

(Carstensen 1984).

An arctic tern was seen above Beaver Creek (table 10) in late August 1988. The species migrates from Alaska to the high latitudes of the southern hemisphere, one of the 

longest migrations in the world (Terres 1980). Arctic terns eat small fish, insects, and 

small invertebrates (Paul 1984). Kessel (1979) identifies the arctic tern as a species 

typical of her grass meadow habitat. The arctic tern is not an abundant waterbird; the 

coastal population is probably about 25,000, with a few thousand more in the interior 

(Paul 1984).

Belted kingfishers nest in gravelly cut banks along Beaver Creek and dart over the 

river from overhanging limbs. They eat mainly fish, which they dive into the water to 

catch, but frogs (including the tadpole stage) can be a significant part of the diet (see 

,fig. 32) (Terres 1968).
51

Table 10-Checklist of birds known to occur or that may occur in the Serpentine 

Slide Research Natural Areaa

Order and

common name Scientific name Comments

Gaviformes:

 Common loon Gavia immer Probable nesting on beaver lodge

 Arctic loon Gavia arctica

 Red-throated loon Gavia stellata

Podicipediformes:

 Red-necked grebe Podiceps grisegena Possible nesting on slough, beaver

 ponds

 Horned grebe Podiceps auritus

Anseriformes:

 Canada goose Branta canadensis Probable breeder and migrant

 Snow goose Chen caerulescens Possible migrant

 Mallard Anas platyrhynchos Probable breeder and migrant

 Pintail Anas acuta 2 pairs seen on beaver pond

 Green-winged teal Anas crecca Remains of kill seen in beaver

 meadows

 Blue-winged teal Anas discors

 Northern shoveler Anas clypeata

 American wigeon Anas americana

 Redhead Aythya americana Occasionally nests on Yukon

 Flats and Tetlin

 Ring-necked duck Aythya collaris Rare breeder in Alaska

 Greater scaup Aythya marila

 Lesser scaup Aythya affinis Nesting habitat is dry grass near

 shores

 Common goldeneye Bucephala clangula Nests in tree cavities, Yukon Valley

 Barrow’s goldeneye Bucephala islandica Nests in tree cavities or rocks

 and cliffs

 Buff lehead Bucephala albeola Seen on Beaver Creek, nests in

 tree cavity

 Harlequin duck Histrionicus histrionicus

 White-winged scoter Melanitta deglandi

 Surf scoter Melanitta perspicillata

 Common merganser Mergus merganser

Falconiformes:

 Goshawk Accipiter gentilis Seen in bottom-land white spruce

 forest

 Sharp-shinned hawk Accipiter striatus Probable in RNA

 Red-tailed hawk Buteo jamaicensis

 Rough-legged hawk Buteo lagopus

 Golden eagle Aquila chrysaetos Seen in White Mountains

 Bald eagle Haliaeetus leucocephalus Seen over Beaver Creek

 Marsh hawk Circus cyaneus

 Peregrine falcon Falco peregrinus anatum Seen in White Mountains

 Merlin Falco columbarius Uncommon in Alaska

 American kestrel Falco sparverius

Galliformes:

 Spruce grouse Canachites canadensis b

 Ruffed grouse Bonasa umbellus b

 Willow ptarmigan Lagopus lagopus b

 Rock ptarmigan Lagopus mutus b

 Sharp-tailed grouse Pedioecetes phasianellus b

See footnotes on page 53.
52

Table 10-Checklist of birds known to occur or that may occur in the Serpentine 

Slide Research Natural Areaa (continued)

Order 

and common name Scientific name Comments

Charadriiformes:

 Semipalmated plover Charadrius semipalmatus Seen in RNA on Beaver Creek

 flood plain

 American golden plover Pluvialis dominica Species of dry tundra

 Lesser yellowlegs Tringa flavipes Seen in RNA along Beaver Creek

 Solitary sandpiper Tringa solitaria Possible, nests near beaver ponds

 in abandoned robin nests

 Wandering tattler Heteroscelus incanus Possible, species is uncommon

 in interior

 Spotted sandpiper Actitis macularia Seen in RNA along Beaver Creek

 Upland sandpiper Bartramia longicauda Possible on sparsely vegetated

 uplands and grassy meadows,

 not common

 Whimbrel Numenius phaeopus Possible on tundra

 Red-necked phalarope Phalaropus lobatus

 Common snipe Gallinago gallinago

 Long-billed dowitcher Limnodromus scolopaceus Probable migrant

 Surfbird Aphriza virgata Possible breeder in alpine tundra

Semipalmated sandpiper Calidris pusilla Possible migrant

 Least sandpiper Calidris minutilla

 Baird’s sandpiper Calidris bairdii Possible migrant

 Pectoral sandpiper Calidris melanotos Possible migrant

 Long-tailed jaeger Stercorarius longicaudus Possible breeder in alpine tundra

 Mew gull Larus canus

 Bonaparte’s gull Larus philadelphia

 Arctic tern Sterna paradisaea Seen in RNA above Beaver Creek

Strigiformes:

 Great horned owl Bubo virginianus Probable breeder and year-round

 resident

 Hawk owl Surnia ulula Tree cavity nester, probable in RNA

 Great gray owl Strix nebulosa

 Short-eared owl Asio flammeus Possible in tundra, marshes, and

 muskegs

 Boreal owl Aegolius funereus

Coraciformes:

 Belted kingfisher Megaceryle alcyon Seen in RNA on cutbanks of

 Beaver Creek

Piciformes:

 Common flicker Colaptes auratus Common in interior Alaska forests

 Hairy woodpecker Picoides villosus Seen in bottom-land white spruce

 forest

 Downy woodpecker Picoides pubescens Sign seen in RNA, white spruce

 forest

 Black-backed

 woodpecker Picoides arcticus Probable in old-growth white

 spruce

 Northern three-toed

 woodpecker Picoides tridactylus Heard in old-growth white spruce

See footnotes on page 53.
53

Table 10-Checklist of birds known to occur or that may occur in the Serpentine 

Slide Research Natural Areaa (continued)

Order and

common name Scientific name Comments

Passeriformes:

 Alder flycatcher Empidonax alnorum Seen in RNA in alders along

 Beaver Creek

 Hammond’s flycatcher Empidonax hammondii

 Western wood pewee Contopus sordidulus

 Olive-sided flycatcher Nuttallornis borealis

 Horned lark Eremophila alpestris Probable in alpine tundra

 Violet-green swallow Tachycineta thalassina Seen in RNA

 Tree swallow Iridoprocne bicolor

 Bank swallow Riparia riparia

 Cliff swallow Petrochelidon pyrrhonota

 Gray jay Perisoreus canadensis Seen in RNA

 Common raven Corvus corax Common year-round resident

 Black-capped chickadee Parus atricapillus Seen in RNA

 Boreal chickadee Parus hudsonicus

 Dipper Cinclus mexicanus

 American robin Turdus migratorius

 Varied thrush Ixoreus naevius

 Swainson’s thrush Catharus ustulatus

 Gray-cheeked thrush Catharus minimus Seen in RNA

 Mountain bluebird Sialia currucoides Possible, uncommon

 Townsend’s solitaire Myadestes townsendi Uncommon, possible in alpine

 tundra

 Ruby-crowned kinglet Regulus calendula Probable in white spruce forests

 Water pipit Anthus spinoletta

 Bohemian waxwing Bombycilla garrulus Seen in RNA, muskeg near

 Beaver Creek

 Northern shrike Lanius excubitor

 Orange-crowned warbler Vermivora celata

 Yellow warbler Dendroica petechia Seen in RNA, riparian alder

 Yellow-rumped warbler Dendroica coronata

 Townsend’s warbler Dendroica townsendi

 Blackpoll warbler Dendroica striata

 Northern watershrush Seiurus noveboracensis

 Wilson’s warbler Wilsonia pusilla

 Rusty blackbird Euphagus carolinus Seen in RNA, riparian willows

 and alder

 Pine grosbeak Pinicola enucleator

 Hoary redpoll Carduelis hornemanni

 Common redpoll Carduelis flammea Common year-round resident

 White-winged crossbill Loxia leucoptera

 Savannah sparrow Passerculus sandwichensis

 Dark-eyed junco Junco hyemalis Seen in RNA, bottom-land white

 spruce

 Tree sparrow Spizella arborea

 White-crowned sparrow Zonotrichia leucophrys Seen in RNA, riparian shrubs

 Golden-crowned sparrow Zonotrichia atricapilla

 Fox sparrow Passerella iliaca

 Lincoln’s sparrow Melospiza lincolnii

 Lapland longspur Calcarius lapponicus

 Snow bunting Plectrophenax nivalis Probable migrant

a Nomenclature follows USDA Forest Service (1979) and American Ornithologists’ Union (1957). 

b

 Mapped as occurring in area by Alaska Department of Fish and Game (1978).
54

Beaver ponds and river cutoff sloughs are an important bird habitat in Serpentine Slide 

RNA. Pintail and green-winged teal were seen on beaver ponds. A nest, probably of 

a loon, was seen on top of an “island” beaver lodge; a “slide” extended from the nest 

into the water. Occasional groups of two to seven ducks were seen flying over Beaver 

Creek, both upstream and down, at all hours during June 1987. The Beaver Creek lowlands connect to the Yukon Flats, one of the great waterfowl areas of North America.

Species seen in riparian shrub habitats in the RNA include yellow warblers, rusty 

blackbird, alder flycatchers, gray-cheeked thrushes, and white-crowned sparrows. 

Spindler and Kessel (1980) report that their tall shrub thicket type supports the greatest bird species richness (as many as 18 breeding species) and highest occupancy levels 

of any bird habitat in the Tanana Valley. The most abundant species in their tall shrub 

plots were yellow warblers, alder flycatchers, and orange-crowned warblers; these 

three species along with northern waterthrushes, blackpoll warblers, fox sparrows, and 

savanna sparrows were most abundant in the tall shrub type of all the habitats they 

studied. Spindler (1976) also found gray-cheeked thrushes associated with these species in a tall shrub habitat near Fairbanks.

The Alaska Department of Fish and Game (1978) reports huntable populations of 

spruce grouse, ruffed grouse, sharp-tailed grouse, and willow and rock ptarmigan in 

a region that includes Serpentine Slide. Sharp-tailed grouse require fire-maintained 

early successional habitats of dense woody vegetation and grasslands in central Alaska 

(Ellison 1978). Ruffed grouse are closely associated with aspen forests in the winter; 

spruce grouse inhabit mature spruce-birch forests in interior Alaska (Ellison 1978). 

Both sharptail and spruce grouse habitats are restricted in the White Mountains but are 

particularly well represented in Serpentine Slide RNA.

At least two adult goshawks were seen flying over mature white spruce forests and 

Beaver Creek and in the Bluff Flats forest plot in pursuit of bird prey. Goshawks usually are found in mature forests with at least some conifers in the area, and they generally nest in the densest portion of the stand (Jones 1979). McGowan (1975) reports 

that goshawks near Fairbanks nest in all forest types but prefer to build nests in large 

birch trees and, to a lesser degree, aspen trees. Goshawks usually return to a traditional 

nesting area and often build several alternate nests over time (McGowan 1975). Nests 

usually are near an opening 50 to 100 m from the edge of the forest. Often goshawks 

choose to nest near a stream or lake that will provide them both habitat diversity and a 

clear flight path (Jones 1979).

Jones (1979) reports the main prey items in the diet of goshawks in North America. 

Many birds that are the prey of goshawk have been seen in or could be expected in the 

RNA because of excellent habitat; these include mallard, green-winged teal, grouse, 

ptarmigan, woodpeckers, jays, warblers, and blackbirds. Important mammals in the 

goshawk diet that find productive habitat in the RNA are arctic ground squirrel, flying 

squirrel, and snowshoe hare. Another accipiter very likely to occur in the RNA is the 

sharp-shinned hawk. Clarke (1984) reports that sharp-shinned hawks occur in high 

densities across forested landscapes of central Alaska. They nest in young conifer trees 

in dense, young stands of mixed deciduous and coniferous forest and regularly reoccupy old nesting areas. Sharp-shinned hawks near Fairbanks prey primarily on small 

birds, especially hermit, Swainson’s, and gray-cheeked thrushes; dark-eyed junco; 

American robin; yellow-romped warbler; white-crowned sparrow; and yellow warbler 

(Clarke 1984).
55

Species seen or heard in white spruce forests of Serpentine Slide are gray jay, boreal 

chickadee, dark-eyed junco, and northern three-toed woodpecker. Spindler and Kessel (1980) report that for the interior Alaska mature white spruce forests they studied, 

the Townsend’s warbler, Swainson’s thrush, and dark-eyed junco were the three most 

abundant birds (82 percent of total density). In a comparison of all taiga bird habitats, 

they found that Townsend’s warbler, brown creeper, and boreal chickadee were most 

abundant in white spruce stands. Other birds they found associated with mature spruce 

trees include northern three-toed woodpecker and species, such as Wilson’s warbler, 

that use mixed deciduous-coniferous forest. Older white spruce forests have the highest incidence (expressed as a percentage of total bird existence energy) of the raptor, 

timber driller, and foliage searcher foraging guilds of Alaska taiga birds (Spindler and 

Kessel 1980). Spindler (1976) found the following additional species breeding in white 

spruce forests near Fairbanks: yellow-rumped warbler, fox sparrow, hoary and common redpolls, and pine grosbeak and opportunist species in more open stands having a well-developed shrub understory, including white-crowned sparrow, Bohemian 

waxwing, and northern waterthrush.

A Bohemian waxwing was seen in the Beaver Creek flood plain flying out of black 

spruce muskeg, its typical breeding habitat. No bird observations were made in alpine 

areas of the RNA. Violet-green swallows catching insects on the wing were seen 

along cliffs at high and low elevations. The same distribution could be expected of the 

Townsend’s solitaire.

The steep bluffs and cliffs along Beaver Creek produce updrafts that attract soaring 

raptors. Golden eagles are widely distributed in the White Mountains, bald eagles 

range up and down Beaver Creek, and peregrine falcons are known to nest near the 

RNA (Bureau of Land Management 1984).

Mammals—Table 11 is a list of the mammals that occur, or may occur, in Serpentine 

Slide RNA. Two mammals, beaver and grizzly bear, are on the RNA type needs list 

(table 1).

Beaver have a profound effect on the character of the Beaver Creek riparian corridor, and there is little question about the appropriateness of the river’s name (fig. 

60). Beaver ponds in the RNA provide habitat for fish and aquatic birds. The upper 

edges of beaver ponds create temporary grassy meadows; ponds that fill in change the 

topography of the flood plain. New beaver ponds on the bottom-land flood shrubland 

and reverse the direction of ecological succession. Beavers in the RNA have cut large 

amounts of balsam poplar and aspen for food. Beavers can be an important prey for 

wolves. In August 1988, beavers no longer occupied the pond shown in figure 58, and 

the water level fell at least 1.5 m (fig. 61). At the same time, an extensive area of beaver 

activity near bank dens (Shepherd 1984) was discovered along Beaver Creek just 

upstream from the pond. Numerous young balsam poplar had been freshly felled by 

beaver, new pathways were present along the bank of the river, and new beaver slides 

led from the bank into Beaver Creek. The beavers that were in the pond in 1987 either 

were killed, died, or abandoned the pond for fresh new habitat.
56

Table 11-Checklist of mammals known to occur or that may occur in the Serpentine Slide 

Research Natural Areaa

Order and

common name Scientific name Comments

Insectivora:

 Masked shrew Sorex cinereus

 Arctic shrew Sorex arcticus

 Pygmy shrew Microsorex hoyi

Chiroptera:

 Little brown myotis Myotis lucifugus

Lagomorpha:

 Collared pika Ochotona collaris

 Snowshoe hare Lepus americanus b c

Rodentia:

 Hoary marmot Marmota caligata c

 Arctic ground squirrel Spermophilus parryii b c

 Red squirrel Tamiasciurus hudsonicus Seen in RNAc

 Northern flying squirrel Glaucomys sabrinus b c

 Beaver Castor canadensis Seen in RNAb

 Northern red-backed vole Clethrionomys rutilus

 Meadow vole Microtus pennsylvanicus

 Tundra vole Microtus oeconomus

 Long-tailed vole Microtus longicaudus

 Yellow-cheeked vole Mocrotus xanthognathus

 Singing vole Microtus miurus

 Muskrat Ondatra zibethicus b c

 Brown lemming Lemmus sibiricus

 Northern bog lemming Synaptomys borealis b

 Collared lemming Dicrostonyx torquatus

 Meadow jumping mouse Zapus hudsonius

 Porcupine Erethizon dorsatum c

Carnivora:

 Coyote Canis latrans c

 Gray wolf Canis lupus c d

 Red fox Vulpes vulpes Seen in RNAc

 Black bear Ursus americanus Seen in RNAd

 Grizzly bear Ursus arctos b

 Marten Martes americana c

 Ermine Mustela erminea

 Least weasel Mustela nivalis c

 Mink Mustela vision

 Wolverine Gulo gulo d

 River otter Lutra canadensis b c

 Lynx Felis lynx c

Artiodactyla:

 Moose Alces alces Seen in RNAb

 Caribou Rangifer tarandus Seen in RNA

 Dall sheep Ovis dalli Infrequent migrant

 through RNA

a Nomenclature follows USDA Forest Service (1979); general distribution limits from Hall (1981). b Sign 

of the species has been observed in the RNA. RNA is within the species range as depicted by the Alaska 

Department of Fish and Game (1978). d RNA is within the species range as depicted by the Alaska 

Department of Fish and Game (1973).
57
58

Grizzly bear use the Beaver Creek floodplain as a seasonal movement corridor (fig. 

62). Fresh tracks of a large boar and a sow with a young cub were observed along 

Beaver Creek in August 1988. Along the river were numerous grizzly bear bedding 

areas in riparian grass, droppings indicating a diet rich in berries and some fish, and 

territorial markings on young balsam poplar. New grizzly bear paths were seen along 

the river bank, which indicated seasonal late summer and fall use. High-productivity 

riparian corridors provide grizzly bears with favorable travel routes among relatively 

small and isolated alpine habitats in the White Mountains. A black bear sow was seen 

in the RNA in summer 1988 along Beaver Creek. Wolf tracks were seen in the annual 

flood zone of Beaver Creek (fig. 63).

Moose have been seen in the RNA along Beaver Creek. Signs of moose browse and 

moose tracks are common along the Beaver Creek flood plain and in the upper elevation shrub belt near treeline. Moose tracks were also seen along shores of beaver ponds 

and sloughs of Beaver Creek. The area of prime moose habitat, the willow-dominated 

riparian shrub zone along Beaver Creek, is narrow compared to rivers of similar size in 

northern Alaska.
59

The presence of serveral small mammals in the RNA was verified by sign or sighting. 

A red fox was observed in a black spruce stand (see fig. 50) at midday in June 1987. 

The fox was walking and probably hunting voles, its preferred prey (Jennings 1984). 

Flying squirrels require habitat in old coniferous forests containing den trees with 

natural tree cavities, woodpecker cavities, and witches’ brooms (Mowrey 1982). Figure 

64 shows a white spruce tree with witches’ brooms (abnormal growths caused by tree 

rust diseases). Witches’ brooms in the Bluff Flats forest plot appeared to be used for 

flying squirrel denning sites.

Serpentine Slide RNA lacks sizeable areas of high-elevation alpine Dall sheep and 

caribou habitat that is characteristic of the other two RNAs in the WMNRA-Mount 

Prindle and Limestone Jags (Juday 1988, 1989). Dall sheep may occasionally pass 

through Serpentine Slide, but they generally avoid the area in their annual movements 

(Bureau of Land Management 1984). Serpentine Slide is not part of the main summer 

or winter habitat of the resident White Mountain caribou herd, but individuals wander 

through the area. A caribou was seen along the ridge crest on the RNA boundary in 

late August 1983. Serpentine Slide was on the edge of the calving grounds of the

Steese-Fortymile caribou that in the early decades of the century was estimated to 

number over 500,000 (Valkenberg and Davis 1986). As recently as the late 1950s the 

herd-numbering over 50,000-still calved in the area. The Steese-Fortymile

herd completely abandoned the White Mountains calving grounds in the early 1960s 

and has not calved in the area since. The small resident White Mountain herd does 

calve there, however. Caribou may again be numerous in the area at some time in the 

future.
60

Any continental exposures of ultramafic rocks, such as serpentinite, are of some 

mineral interest because these rocks have been the main source of many heavy metal 

ores and other rare minerals. Foster (1969) says of the Beaver Creek serpentinite body, 

“Although the detected amounts of platinum, palladium, and rhodium are low, their 

presence is noteworthy.” Weber and others (1988) give probabilistic estimates for undiscovered mineral deposits in the WMNRA. The highest estimates are for placer gold 

deposits, with low probability for tin, thorium and rare earth elements, and lead-zinc 

deposits, all found in areas outside the RNA. Weber and others (1988) state, “At the 

present time we do not expect significant undiscovered resources of chromium, asbestos, nickel, or diamonds.”

No known mineral or mining claims exist within the RNA. The designation of National Recreation Area under ANILCA precludes further mineral claims under the 1872 

mining law. Old wooden posts on the serpentinite outcrop indicate that a mineral claim 

was staked, but it never was recorded officially. Nickel and cobalt were probably the 

ores of interest.

The surface exposure of nickeliferous serpentinite in the RNA is at the northeast tip of 

a 36-km-long body (Foster 1969). A considerable amount of the entire body is on State 

land, and most of the rest is within the semiprimitive motorized recreation management zone of the WMNRA. Mineral leasing is possible in the semiprimitive zone, but 

significant scientific, ecological, and recreational resources must be protected. The 

WMNRA plan maintains a mineral leasing closure for RNAs, the primitive recreation 

management zone, and the Beaver Creek Wild and Scenic River corridor.

Opportunities for research at Serpentine Slide are numerous and varied. The RNA 

offers outstanding opportunities for studying serpentine geology and geoecology, geomorphology, local climatology, community plant ecology, stream ecology, and wildlife 

habitat relations. The area is a significant educational and interpretive resource because 

it contains special features and a diversity of habitats and is relatively accessible from 

Fairbanks yet remains in a wilderness setting.

One of the most important research topics, which should be studied before visitor 

facilities are constructed or monitoring activities become extensive, is naturally occurring asbestos in the RNA. Asbestos is visible in serpentinite exposed by the slide. The 

potential movement of asbestos into surface water and its incorporation into wildlife 

used for recreational or subsistence harvest should be defined. Asbestos levels in potential drinking water sources and the potential hazard of visitors coming into contact 

with asbestos in Beaver Creek may need to be studied.

An important basic research problem at Serpentine Slide RNA is taxonomic (biosystematic) study of local plant adaptation to serpentinite habitats. The RNA offers the opportunity for collecting species growing on serpentine and comparing their genes with 

collections of the same species growing on “normal” sites. Cultivation of both collections in common gardens, comparative studies of isozymes, and hybrid DNA strands 

would be useful. Serpentine Slide RNA is particularly suitable as a “remote” station 

tied to intensive research and monitoring programs at the Bonanza Creek Experimental 

Forest and Long-Term Ecological Research site on the Tanana River west of Fairbanks. 

The RNA provides good opportunities for studying plant succession on the Beaver 

Creek flood plain, especially studies comparing successional pathways with the welldocumented Tanana River braided flood plain. It contains many ecosystems similar to 

History of

Disturbance

Research
61

those in the Experimental Forest but in a different geomorphic and hydrologic setting. The clearwater Beaver Creek system contrasts with the turbid Tanana River. The 

large-animal component in the ecosystem of Serpentine Slide is intact, unlike Bonanza 

Creek Experimental Forest where big game are subject to great human-disturbance 

effects.

The flora of Serpentine Slide is relatively well collected for a remote area of interior 

Alaska, but the great habitat diversity, the occurrence of special habitats, and the potential for specialized or intensive research projects justify more collection. Important 

habitats that need additional vascular plant collections are alpine tundra, wetlands, 

dry dolomite woodland, serpentinite barrens, south bluff grasslands in the early warm 

season, and midelevation white spruce-birch and aspen forest. Serpentine Slide RNA 

is an ideal location for monitoring the climate of south bluffs, bottomland forest, and 

alpine tundra. Concurrent records of climatic variables in these habitats could make 

important contributions to other studies in the RNA and provide data from an area not 

adequately represented by existing weather stations.

The geologic-geomorphic factors responsible for the origin, movement, and growth 

of the earthslide need to be identified. The slide provides an opportunity for studying 

succession and forest development along with monitoring of periodic land movements, 

erosion, and deposition events. Additional detailed study of the diverse bedrock units 

in the area will improve understanding of the geologic history of east-central Alaska.

The tree-line transect and permanent forest plots are available for periodic remeasurement. Updating the forest plots every 5 or 10 years will reveal tree growth and mortality. Mature white spruce forests along Beaver Creek are subject to losses by fire, 

insects, and river erosion. When these unpredictable disturbance events occur in the 

RNA, comparative studies with predisturbance data will be possible. Predictions of 

global warming make the treeline transects valuable for documenting forest advance 

or retreat. Serpentine Slide is a good location for studies of forest raptors and a good 

base for studying soaring raptors, such as eagles and the peregrine falcon.

Serpentine Slide is on the Livengood C-1 and C-2 U.S. Geological Survey topographic 

quadrangle maps (Livengood C-1, Livengood C-2). Chapman and others (1971) provide 

a preliminary geologic map of the region that includes Serpentine Slide at 1:250,000 

scale. Weber and others (1988) include a 1:63,000 scale updated geologic map of the 

WMNRA including Serpentine Slide. The most recent controlled vertical air photo 

coverage of the area (project 03012 ALK 60) is 1981 color infrared photography at a 

contact scale of about 1:63,000. Air photo frames 3523, 3524, and 3525 provide stereo 

coverage of the RNA. The 1951 black-and-white aerial photographs (at about 1:30,000 

scale) that were used to prepare the topographic map base are available from archival 

sources. Color and black-and-white oblique air photos of the RNA taken in June 1982, 

August 1983, June 1987, and August 1988 are available in the archive file on Serpentine Slide at the University of Alaska Fairbanks. The Steese-White Mountain District 

Office of the Bureau of Land Management in Fairbanks can provide current information on maps and air photos of the area.

Maps and Aerial

Photographs
62

I thank the people who helped in the study and documentation of Serpentine Slide 

Research Natural Area. Dr. Ken Wright provided crucial support and encouragement. 

John Bacone, Director of the Indiana Division of Nature Preserves, helped to establish the Bluff Flats forest reference plot and photograph the area as a volunteer. Larry 

Knapman, Fairbanks District Office, Bureau of Land Management, established and 

measured the tree-line transects. Bruce Durtsche, Steese-White Mountain District Office, Bureau of Land Management, provided logistical support for a site visit. Alan Batten, curatorial assistant, University of Alaska Herbarium, assisted in the identification 

of plants collected in the area. David Murray, curator, University of Alaska Herbarium, 

collected and identified plants on serpentinite exposures. Rob Solomon, University 

of Alaska, provided field assistance in several aspects of site documentation work. 

Florence Weber and Karen Wheeler, U.S. Geological Survey, provided a preliminary 

geologic map of the area and helpful advice.

This work was supported by grants to the Agricultural and Forestry Experiment Station, University of Alaska Fairbanks, from the Bureau of Land Management, U.S. 

Department of the Interior, and the Pacific Northwest Research Station, Forest Service, 

U.S. Department of Agriculture.

When you know: Multiply by: To find:

Celsius (°C) 1.8 (then add 32) Fahrenheit (°F)

Centimeters (cm) 0.394 Inches

Grams (g) 0.3527 Ounces

Hectares (ha) 2.471 Acres

Kilometers (km) 0.621 Miles

Meters (m) 3.281 Feet

Millimeters (mm) 0.0394 Inches

Alaska Department of Fish and Game. 1973. Alaska’s wildlife and habitat. Juneau, 

AK: Alaska Department of Fish and Game. 144 p. [Plus 154 plates].

Alaska Department of Fish and Game. 1978. Alaska’s wildlife and habitat: volume 

2. Juneau, AK: Alaska Department of Fish and Game. 74 p. [Plus 151 plates].

American Ornithologists’ Union. 1957. Check-list of North American birds. 5th ed. 

Baltimore, MD: The Lord Baltimore Press. 691 p.

Armstrong, Robert H. 1983. A new, expanded guide to the birds of Alaska. 

Anchorage, AK: Alaska Northwest Publishing Company. 332 p.

Batten, Alan R.; Murray, David F.; Dawe, Janice C. 1979. Threatened and 

endangered plants in selected areas of the BLM Fortymile Planning Unit Alaska. 

BLM-Alaska Technical Report 3. Anchorage, AK: U.S. Department of the Interior, 

Bureau of Land Management, Alaska State Office. 127 p.

Broderson, Kelvin. 1982. The frogs and toads in Alaska. Wildlife Notebook Series. 

Juneau, AK: Alaska Department of Fish and Game. 2 p.

Brooks, Robert Richard. 1987. Serpentine and its vegetation. Portland, OR: 

Dioscorides Press. 454 p.

Bureau of Land Management. 1984. Proposed resource management plan/final 

environmental impact statement for the White Mountains National Recreation Area. 

Fairbanks, AK: U.S. Department of the Interior. 317 p.

Acknowledgments

English Equivalents

Literature Cited
63

Bureau of Land Management. 1986. Record of decision resource management 

plan for the White Mountains National Recreation Area. Fairbanks, AK: U.S. 

Department of the Interior. 41 p.

Carstensen, Richard. 1984. The greater and lesser yellowlegs in Alaska. Wildlife 

Notebook Series. Juneau, AK: Alaska Department of Fish and Game. 2 p.

Chapman, R.M.; Weber, F.R.; Taber, B. 1971. Preliminary geologic map of the 

Livengood Quadrangle, Alaska. U.S. Geological Survey. Open File Map 71-66 (2 

sheets).

Churkin, M., Jr.; Foster, H.L.; Chapman, R.M.; Weber, F.R. 1982. Terranes and 

suture zones in east central Alaska. Journal of Geophysical Research. 78: B5, 3718-

3730.

Clarke, Ronald Gordon. 1984. The sharp-shinned hawk (Accipiter striatus Vieillot) 

in interior Alaska. Fairbanks, AK: University of Alaska. 130 p. M.S. thesis.

Dearden, P. 1979. Some factors influencing the composition and location of plant 

communities on a serpentine bedrock in western Newfoundland. Journal of 

Biogeography. 6: 93-104.

Ellison, Laurence N. 1978. The grouse in Alaska. Wildlife Notebook Series. Juneau, 

AK: Alaska Department of Fish and Game. 2 p.

Foster, R.L. 1968. Tectonic inclusions from a serpentinite, east-central Alaska. In: 

Geological survey research 1967. Professional Paper 575-D. Washington, DC: U.S. 

Geological Survey: D120-122. Chapter D.

Foster, R.L. 1969. Nickeliferous serpentinite near Beaver Creek: east-central Alaska. 

In: Some shorter mineral resource investigations in Alaska. Circ. 615. Washington, 

DC: U.S. Geological Survey: 2-4.

Gabrielson, Ira N.; Lincoln, Frederick C. 1959. Birds of Alaska. Washington, DC: 

Wildlife Management Institute; Harrisburg, PA: Stackpole Company. 920 p.

Gilluly, J.; Waters, A.C.; Woodford, A.O. 1968. Principles of geology, 3d ed. San 

Francisco: W.H. Freeman and Company. 687 p.

Gjaerevoll, Olav. 1958. Botanical investigations in central Alaska, especially in the 

White Mountains. Part I: Pteridophytes and monocotyledones. NR 5. Trondheim, 

Norway: Det KGL Norske Videnskabers Selskabs Skrifter. 74 p.

Gjaerevoll, Olav. 1963. Botanical investigations in central Alaska, especially in 

the White Mountains. Part II: Dicotyledones. Salicaceae-Umbelliferae. NR 4. 

Trondheim, Norway: Det KGL Norske Videnskabers Selskabs Skrifter. 115 p.

Gjaerevoll, Olav. 1967. Botanical investigations in central Alaska, especially in the 

White Mountains. Part III: Sympetalae. NR 10. Trondheim, Norway: Det KGL 

Norske Videnskabers Selskabs Skrifter. 63 p.

Hall, E. Raymond. 1981. The mammals of North America. 2d ed. New York: John 

Wiley and Sons. 1181 p.

Harms, Vernon L. 1973. Taxonomic studies of North American Sparganium. 1: S. 

hyperboreum and S. minimum. Canadian Journal of Botany. 51: 1629-1641.
64

Haugen, RX; Slaughter, C.W.; Howe, K.E.; Dingman, S.L. 1982. Hydrology and 

climatology of the Caribou-Poker Creeks Research Watershed. CRREL 82-26. 

Hanover, NH: U.S. Army Cold Regions Research and Engineering Laboratory. 42 p.

Hodge, R.P. 1981. Are there really turtles in Alaska? Alaska Fish Tales and Game 

Trails. Winter: 14-17.

Hultén, E. 1968. Flora of Alaska and neighboring territories-a manual of the vascular 

plants. Stanford, CA: Stanford University Press. 1008 p.

Jennings, Larry. 1984. The red fox in Alaska. Wildlife Notebook Series. Juneau, AK: 

Alaska Department of Fish and Game. 2 p.

Jones, D.L.; Silberling, P.J.; Coney, P.J.; Plafker, G. 1984. Lithotectonic terrane 

map of Alaska. In: Silberling, N.J.; Jones, D.L., eds. Lithotectonic terrane maps 

of the North American cordillera. U.S. Geological Survey Open File Rep. 84-523. 

Washington, DC: U.S. Geological Survey. 12 p.

Jones, Stephen. 1979. The accipiters: goshawk, Cooper’s hawk, sharp-shinned hawk. 

Denver, CO: U.S. Department of the Interior, Bureau of Land Managment; Habitat 

management series for unique or endangered species, Rep. 17. 51 p.

Juday, Glenn Patrick. 1983. Alaska’s ecological reserves program: approaches, 

successes, and problems. In: Transactions of the 48th North American wildlife and 

natural resources conference; 1983 March 17-21; Kansas City, MO. Washington, 

DC: Wildlife Management Institute: 531-540.

Juday, Glenn Patrick. 1984a. The interpretation of forest structure at three proposed 

Research Natural Areas across central Alaska. In: Proceedings, 1984 Arctic Science 

Conference; 1984 October 2-5; [Location unknown]. Anchorage, AK: American 

Association for the Advancement of Science Arctic Division: 233. Abstract.

Juday, Glenn Patrick. 1984b. Temperature trends in the Alaska climate record: 

problems, update, and prospects. In: McBeath, Jenifer H., ed.; Juday, Glenn P.; 

Weller, Gunter, assoc. eds.; Murray, Mayo, tech. ed. The potential effects of carbon 

dioxide-induced climatic changes in Alaska: Proceedings of a conference; 1982 

April 7-8; Fairbanks, AK. Misc. Publ. 83-1. Fairbanks, AK: University of AlaskaFairbanks, School of Agriculture and Land Resources Management: 76-88.

Juday, Glenn Patrick. 1987. Selecting natural areas for geologic features: a rationale 

and examples from Alaska. Natural Areas Journal. 7(4): 137-156.

Juday, Glenn Patrick. 1988. Alaska Research Natural Area: 1. Mount Prindle. Gen. 

Tech. Rep. PNW-GTR-224. Portland, OR: U.S. Department of Agriculture, Forest 

Service, Pacific Northwest Research Station. 34 p.

Juday, Glenn Patrick. 1989. Alaska Research Natural Areas. 2: Limestone Jags. Gen. 

Tech. Rep. PNW-GTR-237. Portland, OR: U.S. Department of Agriculture, Forest 

Service, Pacific Northwest Research Station. 58 p.
65

Juday, Glenn Patrick; Zasada, John C. 1985. The structure and development of 

an old-growth white spruce forest on an interior Alaska floodplain site, Willow 

Island. In: Meehan, W.R.; Merrell, T.R., Jr.; Hanley T.A., eds. Fish and wildlife 

relationships in old-growth forests: proceedings of a symposium; 1982 April 12-15; 

Juneau, AK. Juneau, AK: American Institute of Fisheries Research Biologists: 227-

234.

Kessel, Brina. 1979. Avian habitat classification for Alaska. The Murrelet. 60: 80-94.

Kruckeberg, A.R. 1954. The ecology of serpentine soils. III: Plant species in relation 

to serpentine soils. Ecology. 35: 267-274.

Kruckeberg, A.R. 1969. Plant life on serpentine and other ferromagnesian rocks in 

northwestern North America. Syesis. 2: 15-114.

Kruckeberg, Arthur R. 1984. California serpentines: flora, vegetation, geology, soils, 

and management problems. Berkeley, CA: University of California Press. 169 p.

Livengood C-1 [Topographic]. 1969. Washington, DC: U.S. Geological Survey. 

1:63,360; Universal Transverse Mercator projection; colored.

Livengood C-2 [Topographic]. 1969. Washington, DC: U.S. Geological Survey. 

1:63,360; Universal Transverse Mercator projection; colored.

Looney, Robert, A.; Himmelberg, Glen R. 1988. Uftramafic rocks of the Livengood 

terrane. In: Galloway, John P.; Hamilton, Thomas D., eds. Geological studies in 

Alaska by the U.S. Geological Survey during 1987. Circ. 1016. Washington, DC: 

U.S. Geological Survey: 68-70.

Matthews, Sue. 1983. Plovers in Alaska. Wildlife Notebook Series. Juneau, AK: 

Alaska Department.of Fish and Game. 2 p.

McGowan, Jerry D. 1975. Distribution, density and productivity of goshawks in 

interior Alaska. Juneau, AK: Alaska Department of Fish and Game; final report 

Federal Aid in Wildlife Restoration Projects W-17-3, W17-4, W17-5, and W-17-6, 

Job 10.68. 31 p.

Mertie, J.B., Jr. 1917. The gold placers of the Tolovana district, Alaska. In: Mineral 

resources of Alaska, report on progress of investigations in 1916. Bull. 662-D. 

Washington, DC: U.S. Geological Survey: 221-227.

Moore, Thomas E.; Nokleberg, Warren J. 1988. Stratigraphy, sedimentology, and 

structure of the Wickersham terrane in the Cache Mountain area, east-central 

Alaska. In: Galloway, John P.; Hamilton, Thomas D., eds. Geologic studies in 

Alaska by the U.S. Geological Survey during 1987. Circ. 1016. Washington, DC: 

U.S. Geological Survey: 75-80.

Mowrey, Robert. 1982. The northern flying squirrel in Alaska. Wildlife Notebook 

Series. Juneau, AK: Alaska Department of Fish and Game. 2 p.

Paul, Tom. 1984. Terns in Alaska. Wildlife Notebook Series. Juneau, AK: Alaska 

Department of Fish and Game. 2 p.
66

Patric, James H.; Black, Peter E. 1968. Potential evapotranspiration and climate 

in Alaska by Thornthwaite’s classification. Res. Pap. PNW-71. Portland, OR: U.S. 

Department of Agriculture, Forest Service, Pacific Northwest Forest and Range 

Experiment Station. 28 p.

Rune, O. 1953. Plant life on serpentine and related rocks in the north of Sweden. Acta 

Phytogeographica Suecica. 31: 1-139.

Shacklette, Hansford T. 1966. Phytoecology of a greenstone habitat at Eagle, Alaska: 

contributions to geochemical prospecting for minerals. Bull. 1198-F. Washington, 

DC: U.S. Geological Survey. 36 p.

Shepherd, Peter. 1984. The beaver in Alaska. Wildlife Notebook Series. Juneau, AK: 

Alaska Department of Fish and Game. 2 p.

Slaughter, C.W.; Viereck, L.A. 1986. Climatic characteristics of the taiga in interior 

Alaska. In: Van Cleve, K.; Chapin, F.S., III; Flanagan, P.W. [and others], eds. Forest 

ecosystems in the Alaskan taiga: a synthesis of structure and function. New York: 

Springer-Verlag: 9-21. Chapter 2.

Spindler, Michael Andrew. 1976. Ecological survey of the birds, mammals and 

vegetation of Fairbanks Wildlife Management Area. Fairbanks, AK: University of 

Alaska. 257 p. M.S. thesis.

Spindler, Michael A.; Kessel, Brina. 1980. Avian populations and habitat use in 

interior Alaska taiga. Syesis. 13: 61-104.

Terres, John K. 1968. Kingfishers eating bullfrog tadpoles. Auk. 85(1): 140.

U.S. Department of Agriculture, Forest Service. 1979. Species list of Alaskan birds, 

mammals, fish, amphibians, reptiles, and invertebrates. Rep. 82. Juneau, AK: U.S. 

Department of Agriculture, Forest Service, Alaska Region. 102 p.

Valkenberg, Patrick; Davis, James L. 1986. Calving distribution of Alaska’s 

Steese-Fortymile caribou herd: a case of infidelity? In: Gunn, Anne; Miller, 

Frank L.; Skjenneberg, Sven, eds. Proceedings, 4th international reindeer/ caribou 

symposium; 1985 August 22-25; Whitehorse, Yukon, Canada. Spec. Issue 1 

Rangifer..Harstad, Norway: Nordic Council for Reindeer Research (NOR): 315-323.

Walker, R.B. 1954. Factors affecting plant growth on serpentine soils. Ecology. 35: 

259-266.

Weber, Florence R.; McCammon, Richard B.; Rinehart, C. Dean [and others]. 

1988. Geology and mineral resources of the White Mountains National Recreation 

Area, east-central Alaska. Open File Rep. 88-284. Washington, DC: U.S. Geological 

Survey. 58 p.

Weber, Florence R.; Smith, Thomas E.; Hall, Mark H.; Forbes, Robert B. 1985.

Geologic guide to the Fairbanks-Livengood area, east-central Alaska. Anchorage, 

AK: Alaska Geological Society. 44 p.

Whittaker, R.H. 1960. Vegetation of the Siskiyou Mountains, Oregon and California. 

Ecological Monographs. 30: 279-338.


Juday, Glenn Patrick. 1992. Alaska Research Natural Areas. 3: Serpentine Slide. Gen. Tech. 

Rep. PNW-GTR-271. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific 

Northwest Research Station. 66 p.

The 1730-hectare Serpentine Slide Research Natural Area (RNA) contains exposures of 

serpentinite that are toxic to most vegetation; Bupleururn triradiatum is the vascular plant 

most tolerant of serpentine. A 9-hectare natural earth flow has destroyed most vegetation in 

its path. The RNA contains 150-year-old flood-plain white spruce forest, shrubland, and open 

gravel bars; slope forests of white spruce, aspen, and mixed paper birch and white spruce; 

and treeline and alpine tundra. The area contains several beaver dams, lodges, and ponds 

that modify the flood plain and provide habitat for waterfowl and shore birds. The flood plain 

serves as a habitat corridor for grizzly bear and other wildlife. Warm, dry, south-facing bluffs 

support one of the northern-most known populations of the grass Agropyron spicatum.

Keywords: Serpentine, earthflow, grizzly bear, beaver, Agropyron spicatum.

 

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