With the hope of interesting our citizens and our visitors in the recently created Silver Strand Beach State Park, this book is offered to the public. Its mission is to acquaint the visitor with the flora flourishing upon this interesting strip of land, and to present to those desirious of a more intimate knowledge of this vegetative covering such information as may be of service.
As a state park, this area is certain to undergo increasing changes in the near future. Herein is a record of the plants and their distribution before any further changes take place.
Grateful appreciation is also tendered to members of the National Herbarium, Washington, and the Dudley Herbarium, Stanford University, for identifications, and for the use of the herbarium of the University of California.
Geologically, Silver Strand has an interesting history. Along the coast from north to south a current passes along Point Loma, eddying just below Imperial Beach. As a result of this movement of the water, sand is deposited along the shore from Imperial Beach northward, forming a long spit extending to Coronado, while a smaller spit is seen to connect it to North Island. Neither Coronado nor North Island are therefore islands, since they are connected with the mainland by these sand spits. Gradually these sand spits are migrating landward due to the action of both wave and wind. Two obstacles, however, are in the way of this progresss, the action of the vegetation in holding the sand and the construction and maintenance of the roadway.
That this area has been forming for a long period is seen in the deposition of older sands below those which are now being blown by the wind and form the surface covering. The immediate coast area, in general, is gradually submerging, although the previous movement, probably not within historic time, was upwards.
Although Silver Strand is about seven miles long, it is very narrow, rarely exceeding one-eigth mile in width. Storms in the winter of 1933 all but cut through its center, narrowing it to such and extent at this point that the highway was close to being undermined.
An aerial view of the Park shows five general regions: on the west, a wide sandy beach, where storm waves roll and leave debris; inland of this, a ridge of small dunes beyond the reach of the storm-tossed waves; approximately in the center of the park, extending form one end to the other, a highway and railroad track built upon heavy soils imported for that purpose. To the east of these are higher dunes built up by wind action; and, lastly, along the east side, the shore of the bay, in some places clayey or, in other sections, covered with drifted sand, form a narrow beach.
An analysis of the sandy portions shows that it is composed of loose, incoherent, rather coarse sand containing about ninety percent of quartz and a little feldspar, basaltic material being especially prominent. (Analysis by Bureau of Chemistry and Soils, United States Department of Agriculture.)
Climatic conditions are very favorable on the Strand. Temperature ranges are not great as this area is tempered by ocean and bay and, in addition, influenced by both high and low frogs. Weekly evaporation, taken over a two years' period form Livingston porous cup atmometers, show that such rates are considerably lower than those taken farther inland. Although the average seasonal precipitation is 9.73 inches, according to records of the United States Weather Bureau, San Diego, for the past eighty-four years, both high and low fogs aids in lowering the evaporating power of the air to some extent and making it most favorable for plant growth. The Park has slightly less precipitation than most other parts of the county. Farther inland, and, as far as the mountain barriers, precipitation increases. While there are no records of snowfall, frost affecting the vegetation of Mission Beach was last reported in 1912. (F.E. Clements in Plant Succession and Indicators. H. W. Wilso Co. New York. 1928.) Wind velocity averages about six miles per hour, the general direction being from the west. The area constituting the Park lies in the foggy desert climate, according to R J. Russell in Climates of California, University of California Publications In Geography, Vol. 2, No. 4, pages 73-84, 1926. In this respect, therefore, this sandy area differs slightly from sand dune areas farther north in the state. Fires have swept the Park from time to time, the scarred stumps of some of the more fire-resisting species bearing mute witness thereto.
During the rainy season there is an abundance of soil moisture except at the surface, which soon dries after a rain. During the spring and the early summer the water content decreases steadily; later in the summer and until the early winter rains set in, the amount of water available is so slight that it is probable the plants suffer from a water deficit. (Edith A. Purer, in Studies of Certain Coastal Sand Dune Plants of Southern California, Ecological Monographs, Vol. 6, No. 1, 1936.)
Weed plants probably would not have succeeded in maintaining a foothold such as they had originally gained, had it not been for the construction of a highway and of railroad tracks along the entire length of the Strand. The looseness of the sand made it necessary for heavier soil to be brought in for construction purposes, and with this soil came weed seeds. And yet even though this had not been done, the introduction of weed seeds might have been, nevertheless, facilitated by traffic along highway and railroad. As a consequence of this invasion, a majority of species present in the Park are weed species. They grow along the sides of the highway and of the railroad and do not appear to take kindly to the sandy areas or to the marshy grounds. In spite of their large number, however, the aspect still remains that of sand dune plant covering for the latter, emphatically, gives character to the Strand. They are the plants which hold the shifting sands and by reason of this characteristic arouse popular interest.
From the two Greek words, one meaning anemone, and the other meaning like, has come Anemopsis because of the resemblance of the flower to the anemone. The yerba mansa is found in lowlands from the Sacramento Valley to southern California and east to Texas. The creeping rootstalk found below the surface of the ground is peppery and acrid, and is used medicinally. As a remedy for many disorders, it was considered exceedingly valuable by the early Californians.
3. DWARF NETTLE. Urtica urens L.
Fortunately, this annual, with its stinging hairs, is rare in the Park. ... It has come from Europe and is found here as a weed in orchards and gardens. Urtica is an ancient Latin name from the verb meaning to burn.
6. NEMACAULIS. Nemacaulis denudata Nutt.
This little annual, belonging to the buckwheat family, is seen only during spring, and even then it does not add any noticeable attraction to the landscape. ...The Greek names nema, thread, and kaulos, stalk, have been given to it because of its slenderness of stem. It is found on sandy beaches from Los Angeles to Lower California as well as on sandy soil on the western edge of the Colorado desert.
18. SAND-SPURREY. Spergularlia macrotheca (Hornem.) Heynh.
A member of the pink family, this perennial herb is frequent on the border of the Strand along the bay, as it favors saline conditions. The sand-spurrey is found on the sandy borders of salt marshes along the southern Californian coast. Spergularia is a derivative of Spergula which comes from the Latin, sperger, to scatter or to spray, in reference to the seed dispersal.
53. BEACH MORNING-GLORY. Convolvulus soldanella L.
The beach morning-glory is a prostrate perennial with shining, deep-green foliage which spreads on the beach on the level areas between mounds of sand.
57. SEASIDE HELIOTROPE. Heliotropium curassavicum L. var. oculatum (Heller) Johnston
A low, fleshy, rather inconspicuous herb ... Found on the Silver Strand in the small dunes and open places in the sand, usually near the ocean, it is also very common throughout California in stream beds and in low, moist or alkaline places.
101. CORD GRASS. Spartina leiantha Benth.
The California cord grass, a stout, erect perennial three or four feet in height, grows in the salt marshes and tidal flats of the bay side of the Silver Strand, spreading by means of rootstalks... The plant is found in salt marshes from San Francisco Bay southward, and is said to be useful in reclaiming marshland.
107. RUSH. Juncus acutus L. var. sphaerocarpus Engelm.
This plant, related to the grasses, is in the rush family... The plant is found in salt marshes along the coast from San Francisco to Lower California, east to the western border of the Colorado Desert.
To my very dear friend,
Edith A Purer
July 11, 1936
70th Anniversary of Silver Strand Beach State Park:..1932 to 2002
75th Anniversary of Silver Strand Beach State Park:...Here in 2007
It is easy to notice in her writings, the pride she had for State Parks as places of environmental preservation and education. However, it is also to be noted from her Preface that she had a fondness for National Parks, when she writes that Parks "have much to commend them to popular attention. Within their smaller compass they may present features of deep interest to the student and to the casual visitor alike." Of course, we can be thankful that at least a portion of the Silver Strand will be preserved in perpetuity under the wise management of California State Parks.
She continued her interest in the study of sand dunes after her PhD, by further research elsewhere on the Pacific coast. It is of interest to note that Silver Strand State Park is still a state park, celebrating its 70th Anniversary in 2002, and its upcoming 75th Anniversary in 2007. Her book is now sadly out of print, for quite some time now. It would be delightful to see her book brought back into print, with a brief biography about Edith Purer. At this time, I am working on putting her text on this Internet web page for beach lovers, dune lovers, marsh lovers, and nature lovers to access.
Edith Purer studied one native plant with a particularly special interest. It was the Beach Morning-Glory, Calystegia soldanella, that she studied for three years. Her research seems like the biography of a plant as if it is a person in that the behavior of this unique plant which grows only on sandy beaches near the ocean is described. She presented this research at UCLA (University of California Los Angeles) at the 1935 meetings of the Ecological Society of America (ESA). Her paper was presented on June 28, 1935. The title was “Growth Behavior in Convolvulus soldanella.” She discussed a unique phenomenon in this plant called “arches” which she documented in February,1933; February,1934; and March,1935. From February through June, but also in September and October, she visited the “arches” of the Beach Morning Glory to see how they develop. She included two excellent photographs of the arches in her report which was published in Ecology, volume 17, page 548, as part of a 10 page research article. The article was published in October, 1936, three years after her research was completed, and one year after her presentation at the ESA meetings at UCLA. Her research of the Beach Morning Glory and “arches” were part of her larger research focus of a comparison of dune vegetation for her PhD dissertation at USC. When we walk on the southern California beaches and marshes of the 21st Century, or what little is left of them, it might be wise to dream of the past in a melacholy way, and to become Doctor Edith Purer or 'Doc' Ed Ricketts in imagination. At least, we can try to remember and reflect upon the southern California coast of 70 years ago, in our California State Parks. We can pretend and imagine to be in California in the 1930s, when beaches, estuaries, wetlands, coastal strand, and marshlands were still abundant in southern California, from Los Angeles to San Diego.
The California natural ecosystems that Edith Purer studied (coastal sand dunes, vernal pools and coatal salt marshes) are among the most threatened, most rare, and most impacted natural environments of California and the United States. It is worthy at this time in California's history and the current environmental crisis and concern for wetland losses, to revisit the life and research of Edith Abigail Purer. As an example of needed research, an effort to locate more of her photographs of 70 years ago would be finding "thousands of words" as in the colloquial phrase, "a picture is worth a thousand words." At least 8 photographs by Edith Purer are known to exist at this time.
In addition to being a scientist, teacher, environmentalist, and California State Parks supporter, Edith Purer was an artist. Here are even more possibilities of "thousands of words." One of her lovely paintings is reproduced at the bottom of the web site and clearly demonstrates the dual nature of Edith Purer. Although it does not appear that she studied deserts professionally as an ecological scientist, she did collect some plants in the San Diego Desert, and she studied the desert through the medium of art. Her paintings have an ecological aspect to them, by painting native plants in the foreground of them. We know that her painting of the beautiful desert landscape scene dates to about the 1930s. It was painted at one of our most beautiful California State Parks, apparently at Palm Canyon in Anza Borrego Desert State Park. Edith Purer was born in 1895, so she would have been about 35-40 years of age at the time of the painting. Edith was a unique individual as she was both a scientist and an artist, something found in only a very few people. It is reminiscent of Robert Stebbins, a noted herpetologist-scientist and emeritus professor at UC Berkeley, but also a painter of desert landscapes and the reptiles that live there. Or Joel Hedgpeth, a marine biologist, who also draws sea spiders, plays a harp, and writes poetry. It is rare indeed, when science and art merge together, but it is what is needed today, and it occurred in Edith Purer, as she was one of those rare individuals of California History during the Depression Era of the 1930s.
1933. Studies of Certain Dune Plants of Southern California. 207p. USC Ph.D Dissertatin
1936. Studies of Certain Coastal Sand Dune Plants of Southern California. In: Ecological Monographs 6: 1-87
1936. Growth Behavior in Convolvulus soldanella. In: Ecology 17: 541-550
2001. Edith Abigail Purer, Ph.D in 1933 from USC: Scientist, Teacher, Author, Artist, and California's First Woman Professional Ecologist in 1930s Depression Era.