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Presenting Nature
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Design Ethic Origins
(1916-1927)
Design Policy & Process
(1916-1927)
Western Field Office
(1927-1932)
Decade of Expansion
(1933-1942)
State Parks
(1933-1942)
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Presenting Nature:
The Historic Landscape Design of the National Park Service, 1916-1942 |
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IV. THE WORK OF THE WESTERN FIELD OFFICE, 1927 TO 1932 (continued)
CONSTRUCTION OF TRAILS
Both civil engineers and landscape architects were involved in the development of trails. The problems of trail building mirrored those of road building but on a smaller scale. As in road design, the landscape architects helped to locate the trails, capturing scenic features and views and protecting significant vegetation, rockwork, and other natural features. The civil engineers were responsible for the construction of trails, which was often undertaken by staff within each park rather than outside contractors. The engineers were concerned with the gradient of the trails, attempting to maintain a varied grade not exceeding eight percent and to use switchbacks only where a gradual curving uphill trail was impossible. The engineers also addressed practical issues like constructing a solid base for a flat, even path free of rocks, tree stumps, and roots. The landscape architects, however, viewed the problems of trail building from the perspective of visual and scenic character. Upholding the principle of harmonious construction, they recommended that structures along the trail and the surface of the trail be as inconspicuous as possible. Structures included the dry-laid rock benches that carried trails; stonemasonry parapets, culverts, and bridges; and trailside improvements such as signs, benches, springs, and lookouts.
As in road construction, the creation of trails in mountainous or canyonlike areas challenged engineers to find a feasible route and often required drilling and blasting. Equipment was transported by horse or mule, and workers relied on safety lines. The landscape architect's challenge in such cases was to ensure that the excavation did not mar the natural beauty of the area and that scars were inconspicuous, especially when viewed from popular viewpoints. The Ptarmigan Trail in Glacier, the Four-Mile Trail in Yosemite, and the New River Trail at the base of the Grand Canyon all posed such challenges.
By the end of the 1920s, the Landscape Division was becoming more and more concerned about the visual compatibility of trails with their surroundings and significant natural features. The timber constructions that led visitors up Moro Rock in Sequoia, to scenic viewpoints along the Yellowstone River and across fields of thermal geysers in Yellowstone were considered outmoded and intrusive and more naturalistic solutions were sought. In 1926, while visiting Yellowstone to provide a professional opinion on the boundary dispute along the Bechler River, landscape architect Harold Caparn made a number of recommendations to improve the landscape character of the parks. One of these concerned the observation decks along the Grand Canyon of the Yellowstone. Caparn urged that the wooden stairways, ramps, and railings that had been installed about 1920 be replaced with earthen paths and masonry parapets of native stone. Such a system could be modeled and colored to blend into nature's surrounding rockwork. Hull and Vint had designed similar walls the year before for Yellowstone's Apollinaris Spring, a heavily visited natural spring that had become a problem from both a sanitary and an aesthetic standpoint and that was rehabilitated into an appealing natural garden. [61]
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| The foot and bridle trail, stone masonry parapet, and entrance to the Ptarmigan Tunnel in Glacier National Park illustrate the advances made in trail construction by the civil engineers and landscape architects of the National Park Service in the late 1920s. The tunnel was blasted through 180 feet of solid limestone and had enough clearance to carry a person on horseback. (National Park Service Historic Photography Collection) |
In 1927, Davidson conferred with Ansel Hall on the potential development of an interpretive program at Artist's Point, Grandview, Lookout Point, and Inspiration Point along the Grand Canyon of the Yellowstone. In anticipation of Hall's obtaining private funding to carry out the development, Davidson sketched out plans and elevations for the existing and proposed development of trails, walkways, observation platforms, and an observation shelter. Old guardrails and steps made of two-by-fours and wooden lookout platforms on stilts had been built at the scenic overlooks about 1920, and Davidson and Hall worked out plans to replace these structures with rockwork along the lines of that developed at Apollinaris Spring. Hall wanted to construct an interpretive lookout shelter at Artist's Point similar in function to that at Glacier Point in Yosemite. Davidson sent his sketches to the San Francisco office so that Wosky could draw up preliminary drawings in keeping with Hall's ideas for "nature shrines" that were relatively inexpensive. Apparently, the funds that Hall was expecting never materialized, and several years later the idea resurfaced in Yellowstone's first nature shrine at Obsidian Cliff (1931).
Davidson's sketches and their recommendations for masonry guardrails, stone steps, and flagstone flooring for the observation platforms and stairways at the various scenic points along the Grand Canyon of the Yellowstone were the first consideration of the area from a "landscape standpoint." In the next few years and throughout the New Deal, this area received considerable attention as concessionary and National Park Service facilities were removed from the canyon and the observation points, trails, and access roads were slowly redeveloped to replace wooden stairways and platforms with more naturalistic and harmonious constructions of masonry walls and flagstone. The master plans continued to encourage the improvement of this area. [62]
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| In keeping with the 1930s master plans for the Grand Canyon of the Yellowstone, the wooden overlooks constructed about 1920 were rebuilt with flagstone terraces and naturalistic stonemasonry guardrail shaped to blend with the irregular, curvilinear contours of the natural cliffs. Viewed from a distance the manmade walls were indistinguishable from the walls of the natural gorge. (National Park Service Historic Photography Collection) |
The 1932 master plans for the redevelopment of points like Artist's Point recommended a number of variations for stonemasonry and steel guardrails. It was not until the mid-1930s, however, that improvements of this type were actually carried out. After heavy snow destroyed the old wooden platform overlooking the lower falls, the Civilian Conservation Corps rebuilt the overlook at the lower falls with curvilinear masonry walls and paths and bridges built of sturdy logs.
Meanwhile, naturalistic solutions were worked out elsewhere in the national parks. One of the first viewpoints to receive naturalistic treatment using stonemasonry and concrete using crushed native stone was Moro Rock, which had been developed with a wooden framework in 1919. Built in 1931, the new stairway was a series of stairs and ramps 798 feet in length that ascended the granitic dome on the southern rim of the Giant Forest Plateau. The stairway was designed to fit the natural contours of the ridge as closely as possible. From the base of the dome, it followed a natural ledge for about 100 feet and then ascended through a natural crevice to an observation platform at 6,645 feet. The trail then climbed a steep stairway along the crest of the ridge and crossed the eastern wall of the rock on a series of ramps supported by masonry retaining walls, before reaching another natural crevice. After continuing to pass through natural crevices along the crest, the trail then followed a series of switchbacks to reach the summit at 6,715 feet. The trail made extensive use of massive masonry walls and was surfaced with concrete that was mixed to blend in with the natural granite bedrock. [63]
Landscape architect Merel Sager and engineer Frank Diehl had selected the route and the building materials to blend the new stairway into the natural scenery to the greatest degree possible. The new stairway avoided the rectilinear lines and angles of the old stairway, which perched awkwardly upon the dome. Instead, it curved naturalistically and was shaped to fit into the natural crevices and along the natural ridges. Retaining walls and protective guardrails were made of randomly coursed rubble masonry of local granite. Ramps led over natural bedrock or were surfaced with concrete mixed with crushed stone matching the coloration of the granite. The result was a durable, safe, and harmonious stairway that could handle the large amount of traffic the site attracted. [64]
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| Photographed in 1939, the nature trail across Norris Geyser Basin, in Yellowstone, inconspicuously guided visitors safely among the geysers, fumaroles, and hot springs. The curvilinear, elevated boardwalk was built by the Civilian Conservation Corps in the summer of 1936. The curving walk created a loop around the geyser basin and connected with a footpath that led in sweeping arcs to the trailside museum, parking area, and other facilities on the hill. Interpretive markers supported on slender poles identified the features. The flagpole and jerkinhead gable of the museum roof are visible midway along the line of trees on the hill. (National Park Service Historic Photography Collection) |
The Landscape Division drew heavily on its experience in road construction in making improvements along trails. Although trails differed from roads in scale, the functional and design problems of trail building were similar to those of road building, particularly in popular areas. Concern for visitor safety as well as access necessitated, for example, the grading and surfacing of trails and the construction of sturdy bridges, stairways, and protective barriers, which in turn called for harmonious and inconspicuous solutions. In some areas, such as Sunrise Ridge on the Yakima Park Road at Mount Rainier, the installation of walks and protective parapets was integrally linked to the development of park roads. In other areas, such as the promenade at Rim Village in Crater Lake, trails were developed independently from the road program but adopted many of its solutions.
The lessons of surfacing roads with macadam of crushed gravel taken from native stone and constructing masonry walls of native stone with exposed weathered surfaces were readily applied to trails. Not only could these improvements be made on site with existing local materials requiring the portage of only essential equipment, but the improvements themselves could also be fashioned to achieve naturalistic curvilinear lines that at once followed nature and blended inconspicuously with the natural setting. One of the most remote developments of this type was the Ptarmigan Trail and Tunnel constructed at Glacier in the late 1920s. Here a tunnel was necessary to pass through 180 feet of solid limestone at an elevation of 7400 feet. The tunnel was approached along a trail carved into the side of the cliff and protected by an irregular stonemasonry guardrail that blended with the surrounding rock. The achievement was a remarkable engineering feat and a notable success in blending manmade improvement and natural scenery to fulfill the goals of landscape protection and accessibility. [65]
Building trails across geyser formations in Yellowstone demanded a different solution. The story behind the design of the Formation Trail at Old Faithful indicates the designer's varied concerns, from public safety to visual appearance. Earlier trails had been laid out in the 1920s. In some areas, logs eight or ten inches in diameter had been placed end-to-end along the ground in parallel rows to form an unsurfaced path about six feet wide. Kenneth McCarter, the park's resident landscape architect in 1929, felt the trails closest to Old Faithful should be at least ten feet wide to handle the foot traffic, including guided tours, that the site needed to accommodate. He also argued that concrete and masonry were inappropriate materials for constructing paths because they permanently defaced the formations. Therefore he suggested that while the use of log curbing should be continued, it should be topped with planks to form a wooden boardwalk above the surface of the open grassland.
Hot pools were a hazard to public safety at Yellowstone's several geyser basins. At Old Faithful there were six such pools, and McCarter doubted the adequacy of the log trails to serve as a safeguard. He recommended that curbing be installed six to eight feet away from each hazardous pool and that low signs marked "dangerous" be placed around the pools. He felt these would "serve the purpose of warning the tourists and would not seriously interfere with the natural beauty of the pools or the landscape." [66]
McCarter's idea was followed at Old Faithful and again at Norris Geyser Basin in the mid-1930s when the Civilian Conservation Corps, following the area's master plan, constructed a system of naturalistic trails that led into the basin and wound around the geysers in a loop before returning to the trailhead and ascending the hillside to the parking area, trail museum, and comfort stations.
The achievements of the late 1920s and early 1930s established precedents that were followed and modified to suit local conditions during the New Deal. Trail improvements were slated for the most popular scenic attractions in other national parks, including the Grand Canyon of the Yellowstone with its many viewpoints, the South Rim of the Grand Canyon, and Carlsbad Cavern. The advances in masonry guardrails and the development of surfaces that used natural materials made it possible to adjust construction and appearances for local topography, conditions, and setting and at the same time construct sturdy and durable improvements that could sustain adverse weather conditions and heavy visitor use. Many of the trail improvements funded by Public Works Administration allotments followed the principles and incorporated the methods of blending and harmonization that the Landscape Division and Engineering Division had worked out by 1930. The Civilian Conservation Corps working in both national and state parks perpetuated these principles and practices to an unprecedented extent.
By 1930, improvements were taking place in the construction of trail bridges. Designs and materials depended on the site, setting, and function of the bridge. Bridle trails, for example, required bridges of greater strength, width, and clearance than foot trails. While simple cross-plank bridges were sufficient to carry hikers across streams, more elaborate solutions were sought for deep precipitous gorges. Log bridges were generally preferred, and by the end of the 1920s, efforts were being made to fashion them from logs similar in size to those in the surrounding forests. While a few bridges, such as the suspension bridge carrying the Kaibab Trail across the Colorado River at the base of the Grand Canyon, were particularly notable as engineering achievements and were designed by national park engineers, they heralded advances in landscape design as well. Like road bridges, trail bridges were designed to fit into their sites and harmonize with their natural settings. The Kaibab bridge was built in the late 1920s to replace an earlier one. The approaches were tunnels carved through the canyon walls with naturalistic cavelike portals. The bridge, constructed of steel cables and girders, was stained a special color to blend in with the canyon walls and river sediments. This was the first major application of staining to match metal surfaces with natural scenery.
In the late 1920s, the park service focused increasingly on designing and building sturdy trails that could serve those on horseback as well as those on foot. Considered outstanding were the five-foot-wide Kaibab Trail of the Grand Canyon, the trails to the East and West Rims of Zion, the High Sierra Trail from the Giant Forest toward Mount Whitney in Sequoia, and the Four-Mile Trail from Yosemite Valley to Glacier Point. [67]
In October 1934, the Engineering Division published its first standards for foot and bridle trails. These would be used by the builders of national park trails for several decades. The standards developed by Chief Engineer Frank Kittredge and his staff were instructions for trail-building in the form of a large sheet with diagrams that could be folded into a pocket-size reference guide for use in the field. These standards ensured that foot and bridle trails were durable, safe, and pleasurable to use.
Specifications for building trails called for a standard width of four feet, which could be accomodated by cutting into the slope or by benching the supporting ground with a dry-laid wall of large stones. Dry, random rubble walls could be built downhill to retain soil and rocks on a steep slope or uphill to retain material above the trail and prevent slides. All walls were to be battered. The rate of grade was limited to 15 percent except in extreme cases, and grades of less than 15 percent were recommended wherever possible without unduly extending the length of the trail. To avoid excessive construction costs, grades of 18 percent and 20 percent were allowed in short stretches of not over 150 feet. The grade was to vary at intervals, in order to "avoid all the strain being confined to a certain few leg muscles."
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| Photographed in 1934, the naturalistic system of footpaths atop Cadillac Mountain in Acadia dispersed visitors from a parking loop at the end of mountain road to numerous panoramic viewpoints. Designed in 1931 by Charles Peterson, head of the new Eastern field office, the paths successfully blended with the summit's natural character and coloration. The paths inconspicuously wound among the gentle contours of the granite summit. The paths followed the surface of the natural pink-colored bedrock and, wherever needed, naturalistic rockwork provided manmade coping and steps. (National Park Service Historic Photography collection) |
Detailed instructions and diagrams were given for the construction of drainage features, switchbacks, and dry rubble walls. For drainage, dips and water breaks were to be built into the trail at regular intervals, and culverts and bridges were to be built only where simplier solutions were inadequate. The precipitation and runoff characteristics of a locality were to be studied to properly determine the type and spacing of drainage features best suited to the conditions. Although a curving alignment was preferred throughout the trail, switchbacks could be introduced on steep slopes provided the turn itself could be built upon level ground. In building dry rubble walls, attention was to be given the slope of the footing and joints and the batter of the inner and outer walls to ensure that the stones were laid firmly in place. [68]
The landscape architects of the Branch of Plans and Designs (formerly Landscape Division) reviewed and approved all phases of trail location, the construction of culverts and walls, and the removal of large trees. Trail-builders were asked to make sure that all evidence of construction outside the trail prism was held to a minimum to preserve the natural setting. The ground was to be cleared to provide a ten-foot clearance above the trail, and no more than one-foot to either side of the trail or the cut or filled areas. The trail was to be routed around large trees and no large trees were to be cut unless this was impractical. The walls, culverts, and other features were to be constructed to harmonize with the natural setting and to avoid the destruction of natural features. [69]
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Last Modified: Mon, Oct 31, 2002 10:00:00 pm PDT
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