June 1957

YOSEMITE NATURE NOTES VOLUME XXXVI - NUMBER 6 JUNE 1957

Dogwood blossoms mean spring in Yosemite

The high country is open and a naturalist program is in operation at Tuolumne Meadows.

THE MONTHLY PUBLICATION OF THE YOSEMITE NATURALIST DIVISION AND THE YOSEMITE NATURAL HISTORY ASSOCIATION, INC.

John C. Preston, Superintendent D. H. Hubbard, Park Naturalist G. D. Gallison, Assoc. Park Naturalist W. C. Bullard, Asst. Park Naturalist R. W. Carpenter, Park Naturalist (Trainee)

VOL. XXXVI JUNE 1957 NO. 6 FOUR EXOTIC PLANTS AND THEIR CONTROL IN YOSEMITE

By Merrie Jo Warne, Ranger-Naturalist In Yosemite Valley and in other regions within Yosemite National Park there are several exotic or introduced species of plants which might be classed as ornamental, useful, or obnoxious (weeds). In 1948 Mr. Richard G. Lillard compiled a list of 23 species (including apple, pear, cherry, American elm, black locust, wisteria, and lilac), that were first introduced by James C. Lannon, James M. Hutchings, and other early settlers. These exotic plants occur most abundantly in areas that have been developed or used since 1859. Mr. Lillard's article entitled "Exotic Plants in Yosemite Valley" appeared in the August 1948 issue of Yosemite Nature Notes, and in it he makes the statement "Either these belong in any new Yosemite flora to be published or else they should be eradicated. " Mr. Lillard's statement, coupled with a personal interest in the native flora and the effects introduced plants have on it, recently led me to consult Mr. Emil F. Ernst, Park forester since 1932, concerning the eradication and control methods now being employed against common mullein, Klamath weed, and bull thistle, which are fairly widespread in and around Yosemite Valley. This article will be primarily concerned with the information obtained from Mr. Ernst. Bull thistle (Cirsium lanceolatum) is a perennial growing 2 to 31/2 feet tall with deeply lobed, dusky green leaves and numerous spines. The bases of the leaves wrap around the

stem and extend out to form prickly wings. The rose-purple flower heads are 1/2 to 2 inches high. Several years ago bull thistle was a common component of the large meadows and roadside plant communities in Yosemite Valley. Although it was originally a native of Europe, it is well adapted to local conditions and until control measures were brought against it, bull thistle threatened to crowd out many less hardy native plants. The common mullein (Verbascum thapsus), another hardy individual introduced into the United States from Europe and now found in the flats and valleys and in the Sierra Nevada and North Coast Ranges of California, is a stout densely woolly plant 3 to 6 feet high with relatively small yellow blossoms that occur in dense spikes. The bases of the crowded leaves form wings around the stems. Mullein, too, competes with native species and so represents a threat to them. The time and method by which bull thistle and mullein were first introduced into Yosemite Valley are not known. They have been well established for at least 30 years, but since World War II Mr. Ernst and his workers have succeeded in reducing them by about 80% so that they are no longer obnoxious intruders in the Valley meadows. In controlling mullein and bull thistle, 2,4,5-T, a form of 2,4-D, a plant growth hormone chemical, has been applied to the leaves and stems as a liquid spray administered from back pack pumps. This hormone must be applied before the plants attain maturity while they are still actively growing. It begins to operate immediately by speeding up the life processes so that the plant soon "burns itself out " and death results. Although bull thistle and common mullein are now being held in check, it is doubtful that they will ever be completely eliminated from the Yosemite area. The European St. John's Wort Klamath weed (Trifolium hypericoides) has become a pest in abandoned or poorly tilled fields in California.

European St. John's Wort or Klamath weed Possibly seeds were carried into Yosemite Valley in the coats of horses brought from the foothills. The flowering stalk of this perennial, 1 to 2 feet high, is well clothed by small dark green, linear leaves. On the delicate yellow petals are tiny black dots. The stamens are numerous. Individual Klamath weed plants are rather attractive; however, this hardy plant has spread rapidly and is now in direct competition with many native meadow plants. In plant communities where Klamath weed is the dominant species, it is definitely a fire hazard during the fall months, because the stems and leaves become completely dried out and they contain a resin-like substance which is easily ignited. Wherever it becomes established and is not controlled, this weed threatens to take over and crowd out all other species. In several states Klamath weed is kept under control by biological means.

After experimentation to determine an effective means of controlling the spread of Klamath weed in Yosemite National Park, two species of Klamath weed beetles were introduced in 1951 (Chrysolina gemellata and C. hyperici). These beetles came to the west from Europe by way of Australia and are definitely specific in their food requirements, since they will eat only Klamath weed. When Klamath weed dies out, the beetles starve to death so they are in no way obnoxious and do not damage other vegetation. The first beetles brought into Yosemite Valley were collected from near Eureka, California, and the last batch of 25,000 came from an area near Coloma and Grass Valley, California. At the present time, according to Park Forester Ernst, the beetles are propagating and they have the Klamath weed in check; however, the situation could be better but again it could be worse. Foxglove (Digitalis purpurea) is one of the worst introduced plants to contend with in Yosemite Valley. It is an extremely hardy but attractive garden flower which may be classified as an escape, since it readily becomes established beyond the tended garden, if extreme care is not exercised to control it. Some of the permanent Yosemite Valley residents have in past years planted foxglove in the areas around their homes. However, on April 26, 1956, a letter from the Acting Superintendent, Mr. Keith Neilson, was issued to all permanent residents. The letter states, 'Planting of exotic flowers must be confined to window boxes and areas immediately around structures. They must not be allowed to spread into the surrounding native vegetation.'

The permanent residents have cooperated fully and have removed these plants from their gardens. During the past few years several groups of foxglove plants have been found at isolated spots along the valley roads. Whenever these plants are discovered they are removed so that they have not yet become well established in the native vegetation.

For those who would question the right of National Park Service officials to exercise control measures against foxglove, bull thistle, mullein, and Klamath weed, when they are found growing within a National Park, the original authority for such control measures dates back to the Enabling Act which was passed on August 25, 1916 and which established the National Park Service and its basic policy which is " To conserve the scenery and the natural and historical objects and wildlife therein... ". Since none of the four plants here discussed are native to the area, since they were all introduced by carelessness and more than likely thoughtlessness, and since they are all in direct competition with native plants that are to be preserved in their natural state "for the enjoyment of future generations," their growth must be controlled.

GOLIATH OF THE FUNGI

By Neil R. Bassett, Ranger-Naturalist To the average park visitor the fungus brings forth visions only of mushrooms and toadstools, and he would be surprised to learn of the multitude of forms to be found in Yosemite alone. Of more than passing interest is the fact that a fungus makes up part of the lichens which so thoroughly streak or cover Yosemite's rocks. The other component of lichens is an alga.

Also included among the fungi in the park are several species of puffballs belonging to the family Lycoperdaceae. The giant puffball (Calvatia gigantea) appears to be represented by a specimen recently collected and examined by Mr. Ricardo Werner of Rosario, Argentina. The specimen measured 52 inches in diameter, and weighed 15 1/2 pounds. It was found in its typical habitat of pine needle duff, shaded by ponderosa pine (Pinus ponderosa). The locale was near the loop road at the upper north end of the Wawona Meadows at an elevation of about 4,000 feet. It was placed on display in the wildflower garden behind the Yosemite Museum.

The general size and shape were still recognizable on about the first of August. Our Yosemite specimen, then, appears to be of average dimensions when compared to other known unusually large specimens. However, in the Yosemite area it was an unusual find and far exceeded in size specimens of this species normally seen.

According to reliable authorities examples of puffballs measuring up to 3 ft. in diameter and weighing 47 pounds have been measured. Another is reported as having a circumference of 5 ft. 1 inch. Dr. Carl Sharsmith, Ranger-naturalist at Tuolumne Meadows for many years, has seen only one other as large as Mr. Werner's find in the park.

Giant puffballs are considered edible only as long as the flesh remains white; they look not unlike a loaf of sheepherder's bread. When the flesh turns yellow with age the puffballs become very disagreeable and indigestible. Deer, though browsing to a large extent on many species of shrubs, do not appear to relish puffballs. The abundance in our area appears to follow mountain runoff from the surrounding peaks.

OLD ICE HOUSE

By Robert J. Rodin, Ranger-Naturalist The Persian wheel, turned by the horse, moved the ice into the ice-house on the endless belt. Most of us are interested in oddities of the past. In this modern day of electric refrigerators, many children in the present generation have not even heard of an "ice man." On a recent trip to the South Fork of the Merced River above Wawona, I came upon evidence that appeared to be an abandoned log pond and former site of a saw mill. There had once been a pond, but the earth dam now had a large gaping hole in it, a result of the 1955 flood. It is interesting to note that in the washed out area of the dam many larch tree roots are present and exposed but no large trees are growing in the immediate vicinity. A pile of sand and dust was found below the dam.

Local people informed me that in 1884 the Washburn Ditch had created this pond as a fish holding pond. Later a saw mill was established here.

summer. The vast quantities of saw dust below the dam which I had presumed were waste from a saw mill were actually the insulation material of the icehouse. This house, built about 1880, was only recently torn down. It was in use approximately 70 years.

Another item of interest was still at this location. Although manpower was used to cut the ice, and presumably men stood on the dock to guide floating blocks of ice to the ramp, the actual work of lifting these blocks from the pond up over the dam and down into the ice house was accomplished with horse power, using a very ancient device known as a "Persian wheel." A vertical axis around which a horse walked was converted by a gear to a horizontal axis and a wheel on the end of this ran an endless chain on two sprockets up from the pond.

It might interest our readers that this particular principle of the Persian wheel has been used for over 2,000 years and is still used by millions of people today in the Near and Middle East. The wheel on the end of the horizontal axis, instead of pulling ice, usually is larger than this one and has a number of tin cans attached to it. As the camel, water buffalo, or other beast of burden walks in his circle, the tin cans lift water from wells or low canals up onto the fields. It may seem very primitive to Americans but it is economical and amazingly efficient for them.

Ranger-Naturalists have conducted campfires, hikes, and nature walks that are scheduled for Glacier Point, Bridalveil campground, Wawona, Big Trees, Tenaya Lake, Tuolumne Meadows as well as Yosemite Valley. Plan your next trip to Yosemite so that you have time to participate.

Yosemite Falls is at its peak.