Presenting Nature

Cover

Contents

Foreword

Acknowledgements

Overview

Stewardship

Design Ethic Origins
(1916-1927)

Design Policy & Process
(1916-1927)

Western Field Office
(1927-1932)

Park Planning

Decade of Expansion
(1933-1942)

State Parks
(1933-1942)

Appendix A

Appendix B

Bibliography

Presenting Nature: The Historic Landscape Design of the National Park Service, 1916-1942

VI. A DECADE OF EXPANSION, 1933 TO 1942 (continued)

EMERGENCY CONSERVATION WORK (continued)

ROADSIDE NATURALIZATION

Vint's program for landscape naturalization and roadside planting received an immediate boost in 1933 when Emergency Conservation Work began in the national parks. Interest in the "finishing" work of landscape naturalization had arisen, and park designers were just beginning to understand the aesthetic and economic advantages to planting the flattened and rounded slopes along new park roads. In 1931, the first funds for this work were programmed. Now, suddenly, a strong body of labor was available and ready. Through the Civilian Conservation Corps, the service also had an opportunity to hire many well-trained unemployed landscape architects to supervise the work.

Roadside naturalization was a twofold process requiring that slopes be graded naturalistically to form concave and convex curves at a ratio of depth to height of at least 3:1, and preferably 4:1. Revegetation was accomplished either through the natural process of recovery or through the planting of native sod, grasses, ground cover, perennial plants, shrubs, and other forms of vegetation. Duff removed before construction was placed on the slope in either case. Planting also often required stabilization of seeded slopes by embedding rocks in the slopes or building temporary wooden cribbing to keep the soil in place until roots could take hold.

The naturalization of banks after road and trail construction became one of the most important and widespread of all CCC projects. It played a vital role in controlling slope erosion as well as having lasting value for beautification. Great effort was taken to blend the planted vegetation into the natural setting of the roadside. Techniques were developed for what became commonly known as bank blending. Resident landscape architect Harold Fowler of Sequoia, where a planting program was undertaken along the General's Highway, reported,

The steep cut slopes and hills form an ugly scar that has been slow to encourage plant growth. This planting project will help materially to hasten a naturalistic roadside planting. . . . It is not intended that this planting should look like a formal border mass. The object has been to blend the new slope planting into the existing growth above the cut slopes. If the growth is shrubby material above the cut slope, the same type of planting should be carried down on the slope. Care should be taken, of course, not to decrease sight vision on curves. . . In the cases where there are only grass and flowers above the slopes similar planting should be carried down on the slopes. An extreme planting of shrubbery would give the border mass effect, which, as stated before, is not desired. [35]

Many rock-loving and creeping plants had already started naturally on the slopes. Fowler recommended that this type of planting be encouraged and carried out to a greater extent with the occasional use of shrubbery material. Approximately eighty thousand plants were used in eight miles of roadside planting, consisting largely of native plants such as ceanothus (Ceanothus spp.), yerba santa (Eriodictyon californicum), bush poppy (Dendromecon rigida), lupine (Lupinus spp.), manzanita (Arctostaphylos spp.), yucca (Yucca whipplei), and flannel bush (Fremontia californica). Because most of the plants were in the form of cuttings and had been transplanted, Fowler expected that a considerable loss would occur and that it would take several years to create a significant effect. [36]

At Yosemite, as a result of the cooperation between the Landscape and Education divisions, a successful planting program got under way along the newly completed Wawona Road. The program began as an experiment but would have lasting success and would influence the design of park roads for years to come.

In summer 1934, enrollees from one of Yosemite's CCC camps collected numerous seeds of native flowers, shrubs, and trees for planting cut banks and fill slopes. They gathered 291 pounds of seed and twenty-two grain sacks of chinquapin burrs. Species included were sugar pine (Pinus lambertiana), incense cedar (Calocedrus decurrens), white fir (Abies concolor), manzanita (Arctostaphylos mariposa), chinquapin (Castanopsis sempervirens), aster (Aster adscendens), dock (Rumex spp.), pennyroyal (Monardella lanceolata), white yarrow (Achillaea millefolium), senecio (Senecio lugens), bear clover (Chamaebatia foliolosa), phacelia (phacelia heterophylla), pentstemon (Pentstemon spp.), coffee berry (Rhamus californica), goldenrod (Solidago elongata), azalea (Rhododendron occidentalis), wild rose (Rosa californica), gilia (Cilia aggregata and Gilia capitata), wyethias (Wyethia angustifolia), lessingia (Lessingia leptoclada), elder berry (Sambucus cerulea), mountain mahogany (Cercocarpus ledifolius), potentilla (Potentilla spp.), mullein ( Verbascum thapsus), godetia (Godetia spp.), bitter cherry (Prunus emarginata), lupine (Lupinus spp.), California black oak (Quercus kelloggii), shield leaf (Streptanthus tortuosus), and others. [37]

In spring 1935, under the direction of Ecologist Frederic E. Clements of the Carnegie Institution, a new method of planting seed was attempted along the Wawona Road. Previous efforts to stabilize slopes by digging pockets for seeds to germinate had failed. Under the new method, small trenches were dug laterally along the slopes, seeded, and then filled with duff and topsoil. The following were among numerous shrubs, trees, wild flowers, and ground covers planted: California poppy (Eschscholtzia californica), lupine (Lupinus nanus), baby-blue-eyes (Nemophila menziesii), clarkia (Clarkia elegans), globe gilia (Gilia capitata), tarweed (Madia elegans), fiddle-neck (Phacelia tanacetifolia), agoseris (Agoseris heterophylla), yerba santa (Eriodictyon californicum), columbine (Aquilegia truncata), spice bush (Calycanthus occidentalis), owl's clover (Orthocarpus purpurascens), Indian pink (Silene californica), collinsia (Collinsia bicolor), eriophyllum (Eriophyllum confertiflorum), nightshade (Solanum xantii), blue-eyed grass (Sisyrinchium bellum), meadow foam (Floerkea douglasii), fivespot (Nemophila maculata). [38]

Landscape naturalization took several forms. Rock embankments along the Wawona Road were stained "to age the appearance of the large rocks that were blasted in carving out the road and obliterate the rock quarry aspect." In spring 1935, CCC enrollees from the Cascades Camp applied a mixture of linseed oil, mineral oil, and lampblack with two spray guns and a compressor to the fresh rock cuts surrounding the portals to Wawona Tunnel. (National Archives, Record Group 79)

The landscape architect for the Wawona Camp saw roadside planting as his camp's most important work and remarked, "By the installation of small trees, shrubbery, native flowers and grasses, and the banks covered with forest litter and duff, the picture along the Wawona Road is very pleasing, and former scars have been practically obliterated." [39]

Writing in Ecology in July 1935, Clements, who had been involved with the planting of the Wawona Road since 1933, described the road and the experimental work being done there in natural landscaping and soil erosion:

To reduce the steep grade, this [the Wawona Road] has been carved out of the mountain sides in such a way as to produce a continuing series of cuts for thirty miles . . . forming an unsightly scar from a distance. These have been organized by sites and units in accordance with terrain and soil, and a detailed plan for preparation and planting worked out for each. One example of each kind has received the necessary reduction or rounding of the slope, with protective trenching above and terracing on the face, and has been sown and planted to yield natural patterns in general harmony with the vegetation present . . . . In addition the plan contemplates the enhancement of the original stretches of forest and the many recesses and dells. [40]

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