February 1947

Vol. XXVI February, 1947 No. 2

THE MONTHLY PUBLICATION OF THE YOSEMITE NATURALIST DEPARTMENT AND THE YOSEMITE NATURAL HISTORY ASSOCIATION

F. A. Kittredge, Superintendent D. E. McHenry, Park Naturalist M. V. Walker, Assoc. Park Naturalist H. C. Parker, Asst. Park Naturalist

VOL. XXVI FEBRUARY, 1947 NO. 2 DR. WILLIS LINN JEPSON

By Carl W. Sharsmith, Ranger Naturalist Dr. Willis Linn Jepson, the well known California botanist, died November 7, 1946, at the age of 79 years. To lovers and students of Yosemite's flora, the name of Jepson and his indispensable "Manual of the Flowering Plants of California" are synonymous. All will mourn his passing.

Dr. Jepson's interest in the native plants of Yosemite was life-long. During the years 1909 and 1911 he made extensive and thorough botanical explorations throughout most of the Yosemite area, and the large collections thus accumulated provided an important basis for H. M. Hall's valuable book, "A Yosemite Flora." All who know California botanical literature are aware of the fact that Dr. Jepson made additional and equally important field studies in Yosemite National Park on numerous occasions. In September, 1913, he was a leader for the visit to Yosemite National Park of the botanists of the Second International Phytogeographic Excursion. Never before — and quite probably never since — has a larger group of botanists of international reputation assembled at one time in this area. A photograph of this group taken in the Mariposa Grove (Madrono, Vol. 1, 1916) with Dr. Jepson seated in front, is truly a living record of the great among recent and contemporary botanists. It was inevitable that many would turn to Dr. Jepson for leadership in indicating and interpreting the significant features of Yosemite's rich and interesting flora.

Dr. Jepson devoted many laborious hours to the completing of his fourth and final volume of the "Flora of California," a task that was barely finished at the time of his death. This is a monumental work (not to be confused with his Manual) in which innumerable observations are recorded and many life histories are described. It bespeaks a lifetime of intimate study and understanding of California's plants, not the least of which is the interesting and varied flora of Yosemite National Park.

THE PACIFIC DOGWOOD

By Lloyd Mason Smith, Ranger Naturalist One of the most beautiful of the Yosemite deciduous trees is the dogwood. In the spring its delicate, widely opened blossoms make it the most picturesque of trees. During the heat of the summer its verdant leaves contrast sharply with the dark shades of the coniferous trunks. In the fall these same leaves turn a brilliant crimson, changing the underforest into a dazzling spectacle of color. And finally, in the dead of winter, the sagging pendent branches, devoid of leafage, support rims of snow and festoons of icicles.

The dogwood belongs to the plant genus Cornus, a name which was derived from the Latin word for "horn", apparently in allusion to the very tough, hard horn-like wood. The species found in Yosemite National Park is popularly called the Pacific dogwood. Its specific name has a most interesting historical background.

In the year 1830, James Audubon had already started painting his celebrated series of American bird portraits. When he began work on the band-tailed pigeon plate he wanted a typical western tree or flower for the background. In the selection of a typical plant he sought help from his friend Thomas Nuttall, the famous botanist, who had collected extensively in the far west even at that early date.

In accordance with Audubon's request, Nuttall gladly sent him pressed specimens of what he considered an unusual western tree, the then undescribed Pacific dogwood. It was the suggestion of Nuttall that Audubon describe and name this tree. This the bird artist proceeded to do, naming the new tree Cornus nuttalli in honor of his friend. This was the first and only plant ever described by James Audubon, and the original illustrations of the flower, fruit, and leaves can be seen in the beautiful portrait of the band-tailed pigeon.

The exact origin of the common name dogwood is debatable. One version is that the twigs of a European species were used widely in the making of meat skewers (miniature daggers) to hold pot-roasts together. For that reason the plant came to be called the dagger-wood, a name which probably soon became shortened to dogwood. Bailey, in his "Standard Cyclopedia of Horticulture," claims another origin in the fact that a decoction from the bark of one of the English species was used to wash mangy dogs.

The bark of nearly all the species contains the same substances that are to be found in the cinchona, the plant from which the anti-malarial drug "quinine" is obtained. Some believe that the chewing of dogwood twigs may tend to relieve or ward off the characteristic symptoms of that disease. The powdered bark can be used as an effective tooth powder. If the bark is mixed with iron sulphate, it will yield a good black ink. In some species the bark from the roots will give a vivid scarlet dye. The wood itself is of sufficient durability as to be utilized in the making of handles for such tools as mallets and hammers.

The "flower" of the Pacific dogwood is a bit unusual in as much as what are usually mistaken for the big white "petals" are in reality the bracts, inconspicuous in most flowers, but greatly modified and enlarged in the dogwood. A somewhat

similar modification has taken place in the common garden poinsettia. The true dogwood flowers are actually crowded into a dense head in the center of these petal-like structures. Not all species of the dogwood possess the flashy bracts, therefore some are often easily confused with such shrubs as the viburnums.

The fruit of the Pacific dogwood consists of small clusters of from 30 to 40 shiny red berries, each of which contains one hard-shelled seed. These berries are readily devoured by birds and small mammals. The small red berries of several species are edible, and those obtained from a northern variety of dogwood are relished by the inhabitants of that region.

The genus Cornus, with the exception of one isolated species in Peru, is restricted to the northern hemisphere and contains some forty different species. Most of these are shrubs or trees of moderate size; however, one or two of them are so small as to be herbaceous. The Pacific dogwood is found, not only in the Yosemite region, but from the San Jacinto mountains of southern California northward through the Sierra and Coast ranges. It is also found in the Coast ranges of Oregon and Washington and seems to reach its most northerly limit in the mountains of southwestern British Columbia.

MUSEUM NOTES

Two of the finest specimens of the rubber snake (Charina bottae bottae) ever collected in the Yosemite Valley, were kept in the live reptile exhibit throughout the entire season of 1946. Late in the fall on October 13 and again on October 16 one of the specimens gave birth to two young. The young were apparently born dead, for they never seemed to escape from their enclosing egg sac. Both specimens, along with their membranous enclosure, were added to the herpetological collection for further study. (M.V.W.)

YOSEMITE HAS NEW PARK NATURALIST

By M. V. Walker, Associate Park Naturalist

On January 9, 1947, Donald Edward McHenry entered on duty in Yosemite National Park as Park Naturalist, filling the position vacated by C. Frank Brockman who resigned in July, 1946, to accept a position in the University of Washington. Mr. McHenry comes to Yosemite National Park by transfer from the position of Park Naturalist in the National Capital Parks, Washington, D. C., where he has served for the past eleven years. Prior to his tour of duty in Washington, D. C., he spent four years as a naturalist in Grand Canyon National Park, Arizona.

Mr. McHenry attended the University of Wyoming from 1922 to 1928 and was granted a Bachelor of Science degree with a major in botany. He then did graduate work in botany and ecology at the University of Colorado in 1923 and 1929 and was granted a Master of Arts degree in 1929. Additional graduate work was carried on at the University of Colorado in the summer of 1929. Mr. McHenry then entered the teaching field and was appointed assistant professor of botany at the Oklahoma Agricultural and Mechanical College at Stillwater, Oklahoma, which position he held until he entered the National Park Service as Naturalist at Grand Canyon National Park in 1932.

While Mr. McHenry's principal interests are in the field of botany, ecology, and geology, he has, during the past few years, devoted much time to dramatizing and popularizing nature interpretation, appreciation and nature guiding. His work with youth groups and junior science organizations has been outstanding, but he has not neglected the adults, for he has been very active in setting up adult courses in nature leadership and appreciation. Some of this adult training has been at university levels, and the University of Maryland is

now offering college credit to persons taking these courses.

Mr. McHenry has published a number of papers in connection with his interpretive work in the National Capital Parks. Some of his articles have been reprinted in their entirety by popular periodicals in England. He has just recently completed work, in collaboration with the United States Geological Survey, on the preparation of a manuscript dealing with the interpretation of the geological story in the area encompassed by the District of Columbia.

Mr. McHenry has been an active member of numerous scientific and cultural societies in the District of Columbia. He is past president of the District of Columbia Audubon Society. He has been a member of the Biological Society of Washington, the Geological Society of Washington, and the Washington Choral Society. He is also a fellow of the American Association for the Advancement of Science.

Mr. and Mrs. McHenry, and their two boys, Bruce and Keith, hope to be settled in their new home within a short time. We are happy to welcome the McHenrys to the Yosemite Park Service family, and urge that our readers call at the museum on their next visit to the park and get acquainted with Mr. McHenry, who will in turn see to it that you meet the other members of the McHenry family.

N.P.S. Photo by Ralph Anderson

DISEASE ON WESTERN AZALEA IDENTIFIED

By Robert J. Rodin, Ranger Naturalist During the summer months many visitors to Yosemite National Park inquire about a yellow "spotting" disease on the leaves of the western azalea (Rhododendron occidentale Gray). This has recently been identified by Dr. Lee Bonar of the University of California as (Exobasidium colorans Hark.), a fungus disease. This fungus has the appearance of a virus during the summer months because during that period the disease is recognized only by the yellow spots. The more mature gray spores do not develop until later in the season. Numerous spots may appear on a single leaf, some becoming so large that the entire leaf turns yellow. In instances where the yellow spots spread over a large portion of the leaf, the area where the spotting originated often turns brown and finally dies. Young leaves may become infected when they are about half the size of a mature leaf. The disease does not appear to be endangering the lives of the azaleas at this time.

NATURE NOTELETS

On January 15, 1947, two large herons, probably the California great blue heron (Ardea herodias hyperonca Oberholser) were observed on the Merced River near the Sentinel Bridge in Yosemite Valley. The fact that the river was frozen over at this time seemed to confuse them slightly. One flew back and forth, up and down the river, apparently trying to locate some open water. It slowed down several times in its hesitant flight, extended its feet for a landing, but pulled them up again before they touched the ice. It finally settled down on the north bank of the stream, just above the bridge, where it afforded a fine opportunity for close observation. (M.K.)

On the morning of September 30, 1946, two employees of the Yosemite Park and Curry Company rescued an eared grebe (Colymbus nigricollis californicus Heerman) from the bottom of the Camp Curry swimming pool which had only recently been drained.

Perhaps the blue color of the walls and bottom of the pool had deceived the grebe, and when it landed on what appeared to be a nice body of water, it found only a thin film covering the concrete floor. The grebe thus found itself "grounded," since it was within a few yards of open water for a running take-off.

The bird was brought to the Yosemite Museum where an examination proved it to be uninjured. After a number of photographs had been made for the Kodachrome collection, it was taken and released on the Merced River near the Sentinel Bridge, apparently none the worse for this unusual experience. (H.C.P.)

Digitized by Yosemite Online Library Dan Anderson