persisting vegetation in an alpine recreation area in the southern rocky mountains, colorado

Persisting Vegetation in an Alpine Recreation Area in the Southern Rocky Mountains, Colorado

JOHN W. MARR, Ph.D. (Minnesota)

Professor o f Biology, University o f Colorado, Boulder, Colorado 80302, &

BEATRICE E. WILLARD, Ph.D. (Colorado) Vice-President, Thorne Ecological Foundation, 1229 University Avenue, Boulder, Colorado 80302, USA

A BSTRA CT

The alpine tundra region o f the southern Rocky Mountains is a dramatic landscape which attracts many visitors seeking the refreshment that urban dwellers often get from a pri- meval environment. This paper describes the current situa- tion and persisting vegetation o f one o f the more accessible o f these areas, the tundra o f Trail Ridge in Rocky Mountain National Park, Colorado. The harsh nature o f the environment is illustrated from data o f 12 years, and the more important local ecosystems are described. Man's use o f this landscape leads to critical management problems, especially in national parks, because no organism similar to Man participated in these systems during the millions o f years o f evolution which moulded them to their present form.

INTRODUCTION

Alpine tundra, as a characteristic component of mountain landscapes above tree-limit, was probably feared by primitive Man, but modern Man finds it a dramatic and delightful environment for recreation. The highest ridges and peaks in the southern Rocky Mountains of Colorado and adjacent States are capped by tundra which is accessible in many areas by highways, some of which are kept relatively free from snow throughout the year. One of the most heavily used of these areas is Trail Ridge in Rocky Mountain National Park (Fig. 1), where a two-lane highway,

Fig. 1. The 'tundra curves' area o f Trail Ridge, Colorado. Rocks o f a residual weathering remnant are seen in the foreground, and headwall o f a glacial cirque in centre near skyline. The sinuous line is the Trail Ridge Road, but

there is a footpath meeting it to left o f centre. 97

Biological Conservation, Vol. 2, No. 2, January 1970--~ Elsevier Publishing Company Ltd, England--Printed in Great Britail

98 Biological Conservation

kept open from June to late autumn, meanders across twelve miles (19 kin) of gently rolling tundra, providing visitors with intimate contact with tundra and awe-inspiring views of spectacular mountain landscapes.

Approximately 46 million people have visited the Park since its establishment in 1915, and it is safe to estimate that the majority of them have travelled along Trail Ridge Road. The Park personnel con- tinually search for more information on the landscapes which they manage, seeking to provide the greatest possible benefit to the visitor, and at the same time to protect the land from effects that will change its character. Information for their teaching activities has built up rapidly as scientists have worked closely with the Park's staff, but knowledge of visitor effects on the landscapes they come to see has been difficult to acquire.

The Congressional Act of 1956, that appropriated funds for 'Mission 66' in the national parks, provided a small amount of money for five western parks to make ecological reconnaissances of alpine and wilderness areas and to study the effects of visitor use on these ecosystems. Alpine and wilderness areas were selected because of the apparently fragile, easily altered nature of their ecosystems. The funds available to Rocky Mountain National Park supported a contract between the National Park Service and the University of Colorado's Institute of Arctic and Alpine Research from 1958 through 1962. The present paper describes Trail Ridge and its vegetation. A further paper on the effects which visitors have had on the tundra, and another on its capabilities for recovery, are in pre- paration.

TRAIL RIDGE

Natural Features Trail Ridge lies just east of the Continental Divide

where it separates the headwaters of the Colorado River on the west from the Big Thompson Fall, and Cache la Poudre, Rivers on the east. The ridge is more than 12 miles (19 kin) long, with 10 miles (16 kin) rising above tree-limit, which is approximately 11,500 feet (3,505 m) in this region (Marr, 1961). The ridge is oriented northwest-southeast and averages about 1 mile (1-6 kin) in width. The highest point on the ridge is Sundance Mountain (elevation 12,466 feet = 3,798 m) near the centre of the ridge.

The main features of the atmospheric environment of Trail Ridge were measured during five summers and one winter. The resultant short-term data are of limited direct value but they do permit informative comparisons with the more extensive data collected

in the senior author's programme on Niwot Ridge, which is situated at a slightly higher altitude some 40 miles (64 km) to the south of Trail Ridge (Mart, 1961, MS; Marr et al., 1968). Twelve years' data from Niwot Ridge are summarized in Table L Total solar radiation, measured with a Belfort Robitzsch bimetallic actinograph on Niwot Ridge for the year 1965, was 122,480 Langleys (Clark & Marr, 1966). Comparisons indicate that Trail Ridge is windier than Niwot Ridge throughout the year, presumably because the latter is somewhat protected to its west by high peaks; otherwise, little difference was observed in climate between the two areas.

The tundra environment is cold, windy, and highly variable. Summers are characterized by cool average temperatures and frequent thunderstorms which always bring about sudden and extreme temperature changes and often produce sleet and hail. Almost every summer, one blizzard with sub-freezing temperatures spreads a few inches of snow across the tundra, but it melts in a day or two. Autumn is dry and cold, but there are a few clear, calm, and warm, days accompanied by pleasing colours of golden Kobresia (Kobresia myosuroides (Vill.) Fiori & Paol.) and red Mountain Averts (Geum rossii (R.Br.) S6r.). The winter is windy, very cold, and the most cloudy season of the year; blizzards are frequent and severe, but they do not contribute much moisture to the tundra because much of the snow is blown down into the forest. Many tundra ecosystems are snow-free throughout the winter, but they do get some water from wet snow in the spring storms when winds are less strong. Spring is cool and wet at the beginning, but there is frequently an interval of drought in June. Strong winds and a major part of the tundra's precipitation come from the west.

There is no evidence of glaciation on the gently rolling surface of the ridge (Bryan & Ray, 1940; Jones & Quam, 1944; Richmond, 1960) but the canyons to the north, south, and west, have been extensively glaciated several times. The general surface of Trail Ridge has long been considered to be a portion of the dissected 'flat-top peneplain' (Van Tuyl & Lovering, 1935; Wahlstrom, 1947; Lovering & Goddard, 1950), but there is considerable evidence that its low, rounded features may have resulted from processes ofaltiplanation (Machin, 1947) or cryoplanation (Bryan, 1946). The geomorphic processes of nivation, solifluction, and cryopedology, have been active over the entire ridge (Russell, 1933; Richmond, 1960) and have produced depressions, solifluction terraces, felsenmeer (rock fields), and several types of patterned ground (Fig. 2). Most of these features are 'fossil' (inactive) (Osburn et al., 1965; Benedict, 1966), but there is still some activity in a few places.

Marr & Willard: Persisting Vegetation in Alpine Recreation Area, Colorado 99

T A B L E 1

Period Summary by Months o f Mountain Environment at a

Tundra Site 40 miles (64 kin) South o f Trail Ridge, Colorado.

Station No. D-l , Altitude 12,300ft . , Site Ridgetop, Nivot Ridge, Summary for 1953-64

Month

Temperature, Air °F Average No. Days

Min.

Temperature, Soil °F

5-7 In. 11-13 In.

Mean of Temp. Mean of Mean of Mean Mean Daily Above Mean Mean Weekly Weekly

Max. Daily Min. Daily Max. & 32°F Max. Weekly Min. Weekly Max. & Max. & Max. Min. Max. Min. Min. Min. Min.

January 39 14(A) -- 34 3(A) 9(A) 0 25 18(A) 4 9(A) 14 February 41 14(A) -- 25 4(A) 8(A) 0 26 19(A) 4 11 (A) 15 March 41 17(A) - 8 5(A) ll(A) 0 29 21(B) 4 12(B) 17(A) April 49 25(B) -- 8 13(A) 19(A) 0 33 26(A) 8 19(A) 23 May 56 38(A) 5 23(A) 31(A) 3 43 32(A) 16 29(A) 32 June 67 48(A) 11 33(A) 41(A) 15 53 45(A) 25 34(A) 40 July 65 54 27 40 47 29 56 52 34 42 47 August 63 52 19 38 45 28 56 52(A) 35 41 46 September 61 46 7 33 39 12 54 47 32 37 40 October 51 34(A) -- 3 23(A) 30 3(B) 49 38 26 32 44 November 44 22 --21 I l 17 0 33 28 l0 21 24 December 40 17 --20 6 11 0 26 22 --3 13 17

15 16 17(A) 24 31 38 45 46(A) 41 35 27 19

Period 67 32 34 19 26 90 a 56 56 4 25 30 30

Month

Soil Moisture Wind Precipitation % Dry Wt. * Month End

Monthly Vel., mph Monthly In. Water Relative Humidity** 5-7 ln. 11-13 in

Mean Mean Mean Daily

Max. Min. Mean Max. Min. Mean Max. Min. Mean Mean Daily Min. Daily Max. & Max. Min. Min.

January February March April May June July August September October November December

30 20 25 3"85 0"80 2"13(A) 44(C) 21(C) 32(C) 14(F) 91(A) 3 ( A ) 57(A) 74(A) 28 21 24 3'80 0"80 1"88(A) 42(E) 16(E) 36(E) 19(H)96(A) II(A) 62(A) 79(A) 24 16 21 3'15 0"65 2"07(A) 67(A) I9(A) 38(A) 19(E) 97(B) 14(B) 62(B) 79(B) 22 17 19 4'80 0'85 2"28(A) 65 21 40 22(D) 92(B) 8(B) 56(B) 74(B) 18 12 14 5"10 1"10 2'58 59(A) 12(A) 36(A) 19(C) 91(A) 8 (A) 44(A) 68(A) 17 11 13 4"50 0'80 2'17 62(A) 20(A) 37(A) 22(B) 85(A) 5 (A) 34(A) 60(A) 13 9 10 4"50 1'55 2'74 41(B) 16(B) 29(B) 16(B) 87 10 38 63 16 8 11 7'60 0'80 3"00 69(B) 13(B) 31(B) 17(B) 88 8 40 64 19 11 15 5'90 0"25 1"97 51(C) 13(C) 30(C) 16(D) 80 1 38 57 22 15 19 2-45 0"30 1"13 51(C) 19(C) 35(C) 19(D) 81(A) 4(A) 41(A) 61(A) 28 12 24 3'10 0"60 1-49 43(C) 18(C) 31(C) 23(C) 88(A) 0(A) 49(A) 69(A) 31 21 26 4"30 0'40 1'78 53(B) 15(B) 34(B) 20(C) 92(A) 0(A) 53(A) 73(A)

Period 31 8 18 7.6 0.25 25.22 a 69 12 34 19 89 0 48 68

* Permanent Wilting Percentage: 10~ & 4 ~ ** Maximum 100~ Every Month

a Mean Annual for Period

(A) 11 yrs. (B) 10 yrs. (C) 9 yrs. (D) 8 yrs.

Front Range Ecology Project Supported by US Atomic Energy Commission, U.S. Army Quartermaster Research and Develop- ment Command, and University of Colorado.

(E) 7 yrs. (F) 6 yrs. (G) 5 yrs. (H) 4 yrs.

The Bedrock of Trail Ridge is Precambrian Silver

Plume granite and Precambr ian m e t a m o r p h i c - - pr imari ly mica schist and gneiss (Lovering & Goddard ,

1950). In the vicinity of Iceberg Lake, Miocene lavas overlie the older rocks (Wahlstrom, 1944). The rate of soil development varies from one rock type to another, and the soil type, in turn, affects the vegetation pat tern (Willard, 1963); the metamorphic rocks dis- integrate more rapidly, forming a deeper, finer- textured soil than do the lavas and granites.

The regional tundra flora is dominated by the c i rcumpolar element, which makes up ½ to ½ of the total alpine flora (Weber, 1965). The Boreal-Asiatic

sub-element constitutes the second largest group, and Rocky M o u n t a i n endemics comprise the smallest group. All but one of these species are slow-growing perennials (Griggs, 1956), Koenigia islandica L. being the sole annua l in the flora.

Numerous mammals , birds, insects, crustaceans, and other invertebrates, inhabi t this tundra region

100

(Willard, 1963). Among the animals, the Pocket Gopher (Thomomys talpoides fossor) (Hall & Kelson, 1959) and the meadow voles (Microtus spp.) exert the most important animal effects on the vegetation by their burrowing and grazing. Pika (Ochotona princips saxatilis) also influence small areas of tundra through

Fig. 2. View across Trail Ridge to Long's Peak, which is the highest in the Rocky Mountains National Park, and has a thin cover of snow following a summer storm. Inactive patterned ground and a turf ecosystem are seen in the

foreground.

their food harvesting. Elk (Cervus eanadensis) and White-tailed Ptarmigan (Lagopus leucurus) feed extensively on the tundra, but we have not detected any lasting effects which they may have on the vegetation.

The above-reviewed components of the landscape, and many others also, have interacted for millions of years or~ Trail Ridge, producing relatively distinct ecological units or ecosystems (Marr, 1961). The ecosystems that are present today form a mosaic of many different types, controlled primarily by the distribu- tion of snow. There is so much wind during the winter, averaging 25 miles (40 kin) per hour in January, that only those areas with some type of protection (which causes the wind to eddy) have a persistent snow-cover. Even sites where snow is deposited in drifts immedi- ately after a storm will be eroded in time as the wind shifts directions or changes to different flow-patterns. Additional controls of the landscape pattern are activities of small mammals, forces of cryopedology, soil moisture conditions, and degree of soil development, as well as the other environmental parameters which operate in all areas. The range of environmental conditions is so great that no one species of plant grows in all of the ecosystems. The most wide- spread species are Festuca brachyphylla Schultes, Geum rossii, Bistorta bistortoides(Pursh) Small, and the lichen Cladonia pyxidata (L.) Fr.

Main Ecosystems The junior author studied the phytosociology of

Trail Ridge intensively (Willard, 1960, 1963). The

Biological Conservation

following summary of ecological units is taken from her 1963 opus.

FellfieM ecosystems of partially open vegetation occupy the windiest sites where the soil is coarse, rocks are abundant, and there is no snow-cover during nine-tenths of the year (Fig. 3). Cushion plant fellfieM is characterized by having more rock and gravel than vegetation cover; here cushion plants, such as Silene acaulis L., Arenaria obtusiloba (Rydb.) Fern., Paronychia sessiliflora Nutt., and Trifolium nanum Torr., dominate the often rather meagre vegetation.

Alpine cloverfellfieM occurs on sites that are slightly less inhospitable than that of the cushion-plant type. Here there is a shallow snow-cover most of the winter and bare gravel is uncommon. The vegetation covers approximately 70 per cent of the ground, the remainder being occupied by rocks. In addition to the plants

E

listed above for cushion-plant stands, this type commonly includes the following species: Trifolium dasyphyllum T. & G., Calamagrostis purpureseens R.Br., Artemisia pattersonii Gray, Carex rossii Boott, Erysimum nivale (Greene) Rydb., Hymenoxys acaulis (Pursh) Parker, Bryum argenteum Hedw., and Candel- ariella teriigena Ros. This is one of the most beautiful tundra communities in late June and early July, when perfumed clovers, blue Alpine Forget-me-not, and yellow Compositae are all in flower. Somewhat later, the conspicuous and beautiful Rydbergia grandiflora (Pursh) Parker colours the tundra with a yellow hue.

Mountain dryad fellfield is best developed on un- stable substrata, and often forms vegetation-banked terraces with bare gravel steps and dryad 'risers' (i.e. slopes between the steps). Dryas octopetala ssp. hookeriana (Juz.) Hult6n is the dominant plant. Saxifraga caespitosa L. and 90 other vascular species

Fig. 3. FellfieM ecosystem in foreground. Note long patch of late-lying snow below road on left.

including Poa arctiea R. Br., and 45 different mosses and lichens, are common in this type.

Snow-bed ecosystems occur in the abundant sites where snow lies for 60 to 95 per cent of the year. In the deeper beds, the environment gradient outwards

Marr & Willard: Persisting Vegetation in Alpine Recreation Area, Colorado 101

from the area where the snow melts last is so great that several distinct ecosystems usually occur in these sites, commonly arranged in discontinuous bands about the central type. The arctic willow band occupies shallow sites, often on small solifluction terraces, where snow lies for 7 to 9 months of each year. Salix arctica Pall., the dominant species, has twigs which grow prostrate, although the leaves and catkins stand up; the lichen Rinodina nimbosa (Fr.) Th.Fr. is common here.

Hairgrass meadow has the distinction of being our sole alpine tundra ecosystem that is dominated by a grass. Deschampsia caespitosa (L.) Beauv. is the luxuriant, sweet-smelling bunch-grass that dominates this band; it is snow-covered for 8 to 9½ months of the year.

The Toninia-Sibbaldia ecosystem is conspicuous because of its unusual grey-blue colour, which is contributed by the thallus of the lichen Toninia cumulata (Sommerf.) Th.Fr. The other plant that shares in the dominance of this type is Sibbaldia procumbens L., which superficially resembles a clover and turns a rich red in the autumn. Other plants add yellows and bronzes to this community, giving it the appearance of a Persian carpet. This community occupies well-drained sites where snow stays from 9 to over 10 months of the year.

The Drummond's Rush type has a characteristic dark forest-green colour which makes it conspicuous

among the lighter greens of other ecosystems. This type occupies sites where soil moisture is high during the growing-season and snow-cover lasts for 9½ to 11 months. Appropriate sites are common on solifluction terraces, and active cryopedological processes may give these stands a spotty appearance.

The Rocky Mountain sedge ecosystem (Fig. 4) occurs on the outer part of giant solifluction terraces (many metres wide and tens of metres long) where soil moisture conditions are especially favourable for relatively luxuriant plant growth. Snow accumulates in the inner portion of the terrace step and provides a source of water which may persist well into the summer; as the step is flat, and the soil is frozen during much, if not all, of the year, ground-water moves slowly and is available to the plants much later here than in other sites. Under this moisture r6gime, plants stay green in late summer for several weeks after those in most other ecosystems have dried up and turned brown. Winter exposure, in contrast to the summer moisture, is adverse for plants in these sites because they are snow-free during most of the winter. Frost action in the spring and autumn interacts with plant growth to produce frost hummocks that alternate with bare rock and soil, which is often organized into sorted circle-patterned ground. Carex scopulorum Holm is a dominant in this type and the showy flowers of Caltha leptosepala D.C., Pedieularis sudetica ssp. scopulorum (Gray) Weber, and Sedum rhodanthum

Fig. 4. Wet Rocky Mountain sedge ecosystem on giant solifluction terrace in foreground. Koenigia islandica grows on the wet gravel areas between frost hummocks in centre,


Gray, give colour to such areas. A moss, Drepano- cladus revolvens (C.M.) Warnst., is locally confined to this type of vegetation.

The Koenigia islandica ecosystem is the rarest and most distinctive unit in the southern Rocky Moun- tains. The dominant species is our only true annual

Fig. 5. Kobresia myosuroides turf ecosystem in foreground.

plant and the environment is highly specialized, being gravel or humus across which water at or below 46°F (7.7°C) is running constantly (E. Dahl, pers. comm.).

Alpine turf ecosystems are important in tundra regions because they form strong, persistent carpets on the landscape. They are formed by perennial sedges, grasses, and forbs, most of which have the rhizomatous growth-habit although some are caespi- tose. Their roots ramify in the upper layers of soil and work with the rhizomes in building rich soils and in stabilizing substrata. Once established, turfs are highly resistant to disturbance.

Our three turf ecosystems are dominated by Carex rupestris All., C. elynoides Holm, or Kobresia myosuroides. The Kobresia type (Fig. 5) is apparently our climatic climax towards which other ecosystems tend to develop. Its dense turf blankets the substratum, the vegetation cover averaging 92 per cent and being composed almost entirely of the one species. This ecosystem is intolerant of snow accumulation. Various authors have reached this conclusion and the junior author found a field demonstration that proved the point conclusively. Road construction caused a new snow-drift to form in the middle of a Kobresia turf; all Kobresia covered by the snow died, whereas the snow- free plants not only survived but actually throve.

Zootic Ecosystems The physiognomy and most other characteristics of

ecosystems are usually controlled by their plant components, but our tundra containsthree conspicuous exceptions to this generalization.

'Gopher gardens' are formed by activities of the Pocket Gopher (Thomomys talpoides fossor). This burrowing mammal tunnels under the ground, feeding

on plant parts so encountered and piling the dirt produced by its excavations in mounds on top of the ground. The animal tends to concentrate for a time on an area of approximately 16 sq m and then moves to another similar-sized plot. As the enriched, well- cultivated soil absorbs rain and snow-melt water quickly and is well aerated, plants develop to an exceptional size in such areas and a special combina- tion of species comes into being. The more abundant, and showy, species here are Polemonium viscosum Nutt., Mertensia viridis A.Nels., Geum rossii, Bistorta bistortoides, and Campanula rotundifolia L. Occasion- ally, grasses dominate these 'gardens', especially prevalent species being Agropyron scribneri Vasey and Poa rupicola Nash. These 'gardens' are transitory because their substratum is vulnerable to rapid erosion by wind and water. Consequently, they are part of a series which changes progressively through a sequence that has the potential to lead back eventually to the persistent ecosystem of the given site.

The Arctic Sage ecosystem develops on sites of shallow snow-accumulation where the Gopher has disturbed hairgrass meadow or a Toninia-Sibbaldia ecosystem. Ranunculus adoneus Gray makes a brilliant display in this ecosystem as the snow is melting, but Artemisia arctica Less. ssp. saxicola (Rydb.) Hultdn is the true dominant. Other common species are Sib- baldia procumbens, Draba crassifolia Graham, Tri- folium parryi Gray, and Lewisia pygmaea (Gray) Robins.

The Geum rossii ecosystem has an amazing origin. It occurs in the vicinity of rocky sites inhabited by small mammals of the vole genus Microtus. The populations of these animals fluctuate from year to year; when there is a peak in animal numbers, they take on a special behaviour that is not pursued at other times. This behaviour consists of tearing up cushions of Silene acaulis and Trifolium nahum and making them into piles of tiny plant fragments which form a perfect seed-bed for the Geum. Concentrations of Geum seedlings grow in the piles of shredded cushion plants and then spread outwards by stolons.

Use by Man The name Trail Ridge commemorates the use of this

Ridge as a passageway on periodic migrations by prehistoric Man from the plains to mountain parks and back again in summer. The 'Ute Trail' created by this travel is still visible in several places. The archaeological artefacts indicate that the Trail was used 6,000 to 8,000 years ago, and some fragments of information suggest that some of these trips may have taken place as early as 11,000 to 15,000 years ago (Husted, 1962). Use by Indians extended up to the late nineteenth century.

Marr & Willard: Persisting Vegetation in Alpine Recreation Area, Colorado

The early White Man in Colorado seldom ventured onto Trail Ridge (Bird, 1880), but it is likely that by the 1890s occasional hunters and hikers crossed the Ridge (Carothers, 1951). It is unlikely that the Ridge was ever used for domestic grazing, except for an occasional horse (Willard, 1963). The number of people reaching the ridge summit greatly increased with the completion in 1920 of the Fall River Road over Fall River Pass at the west end of the Ridge. The activities of these early visitors were concentrated on the area of the Pass, but a few people walked or rode across the summit of the Ridge on the Ute Trail. The utilization of the tundra region of the Ridge again increased with the opening, in 1932, of Trail Ridge Road. An average of approximately 500 cars per day (averaging 3 visitors per car) crossed Fall River Pass during the summer months prior to 1932. After the new road was opened in that year, the number of cars per day increased markedly, until in 1962 an average of 6,000 to 8,000 cars per day crossed in July and August (average of 3.5 visitors per car).

As Trail Ridge can be reached in a few hours from dozens of schools and many institutions of higher education, many classes make extensive use of this unique and easily accessible field laboratory every year. Autumn days often have delightful mild and clear, windless 'Indian Summer' weather which is perfect for demonstrations and discussions of natural phenomena in the field. Students do sometimes get caught in the occasional storms and find the vegetation and geomorphological features obscured by snow; but even then they learn much aboutthe winter atmospheric environment of the tundra, the conditions and processes of which control many features of this landscape. On week-end days of 'good' weather it is common for several classes from different institutions to be active on the Ridge at one time.

The Park's staff conducts many educational pro- grammes during the summer. In addition, thousands of visitors learn about tundra from the excellent small museum built by the Park in a spectacular tundra setting, and from the self-guiding Tundra Trail along which plants and ecological phenomena are marked and described in a small brochure. In 1962 the junior author, with the help of the National Park Service, Rocky Mountain Nature Association, Colorado State Department of Education, Estes Park Chamber of Commerce, Institute of Arctic and Alpine Research, Thorne Ecological Foundation, and Extension Divi- sion of the University of Colorado, initiated a programme of 'Summer Seminars'. These six-day seminars cover geology, ecology, biology, and conservation, with major emphasis on field studies, and they attract a remarkably diverse group of persons from many professions and different segments of society.

103

FUTURE PROSPECTS

The Trail Ridge tundra is a comparatively persistent landscape type under non-man conditions but it is, unfortunately, both especially attractive to Man and particularly susceptible to destruction by his activities. For example, hundreds of acres of a similar landscape on Pike's Peak in southern Colorado have been reduced to rapidly-eroding gravel by the efforts of Man to maintain a highway to the top of the mountain.

Use of Trail Ridge for both recreation and education will probably increase continuously until the Park is forced to limit the number of persons admitted each day. Currently there is considerable demand for enlarging the highway. Can this landscape absorb the expected increase in human impact and still retain those qualities which now draw millions to experience its rare beauty and drama?

References

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WILLARD, B. E. (1963). Phytosociology of the Alpine Tundra of Trail Ridge, Rocky Mountain National Park, Colorado. Ph.D. Thesis, University of Colorado, 243 pp.

Newsletter of the Commission on Education of IUCN

'Research and education are two complementary lines along which 1UCN is developing its activities', says L. K. Shaposhnikov, Chairman of the Commission on Education of the International Union for Conservation of Nature and Natural Resources, in his leading article in the first issue (July/September, 1969) of this new IUCN Newsletter.

The Commission on Education's cyclostyled circular, first issued last July from IUCN headquarters at Morges, Switzerland, meets the growing need for proper information, cooperation, and integration, in the field of environmental conservation education. This need was made clearly evident at the UNESCO Biosphere Conference in 1968. The primary purpose of the 'Newsletter' is to express the aims, general policies, principles, and problems, of environmental and conservation education to organizations and individuals that are concerned with such education, and to strengthen and develop appropriate national and regional centres that will deal with environmental education.

The first issue contains 20 pages of general information about the structure, tasks, and work, of the Commission on Education of IUCN and its four Regional Committees (in the appendix, a complete list of some eighty members who are active within the Commission is given). The programme of European Conservation Year and the activities

of the International Youth Federation for Environmental Studies and Conservation are briefly described. In the second part of the issue, 18 brief notes report on environmental education efforts and achievements in 14 countries of the world. New books are reviewed and information is given on some international actions.

In the second issue (October/December 1969), circulated in October, the most interesting material (besides brief notes from different countries, book reviews, and reports on actions) are two articles from North America: the first (by Barbara J. Reid, The Conservation Foundation, Washington, D.C.) deals with the urgent problems of urban environmental education, while the second (by Prof. Michel Maldague, Laval University, Quebec, Canada) explains the methodology of the Commission's project of investigation into environmental education in the Province of Quebec.

The Newsletter will be sent free of charge to persons interested in environmental and conservation education on their request to the Editor, Dr Jan Cerovsky, Education Executive Officer, IUCN, 1110 Morges, Switzerland.

ROBERT I. STANDISH, Public Information Officer, 1UCN, 1110 Morges, Switzerland.

persisting vegetation in an alpine recreation area in the southern rocky mountains, colorado

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