Giant Sequoia Management in the National Forests of California1
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Giant Sequoia Management in the National Forests of California1 Ronald E. Stewart Sandra H. Key Bruce A. Waldron Robert R. Rogers2 Abstract: The USDA Forest Service is one of six public agencies that manage giant sequoia (Sequoiadendron giganteum [Lindl.] Buchholz). Giant Sequoia Locations The history and biology of the species and the increasing national interest Giant sequoia are found naturally only at elevations of define this agency's present management philosophy. Today's manage- ment objectives are to protect, preserve, and restore the existing giant 4,500 feet (1,365 meters) to 7,500 feet (2,275 meters) in a sequoia groves and to extend the range of the species. Future management narrow 15-mile (24 kilometer) by 260-mile (420 kilometer) complexities include responding to the technical silvicultural needs of the range in the west-side Sierra Nevada of central California species and the public preference for esthetic values. (Weatherspoon 1986). The sequoias typically form groves as they grow among a mixture of conifer species including white fir (Abies The National Forests in California are responsible for concolor), sugar pine (Pinus lambertiana), incense-cedar the conservation of 41 groves of giant sequoia. To redeem (Calocedrus decurrens), ponderosa pine (Pinus ponderosa), this responsibility, after nearly a century of fire suppression, California black oak (Quercus kelloggii), and often Douglas-fir the agency is exploring ways to restore the groves to a natural (Pseudotsuga menziesii) (Harvey 1980). Areas covered by condition when fire played a major role in their ecology. If the groves range in size from I acre (0.4 hectare) to 4,000 the conditions created by fire are not reestablished in the acres (1,600 hectares). In total, the groves occupy a combined groves, giant sequoia could be replaced by other species. area of about 36,000 acres (14,400 hectares) within a range Specifically, fuels build-up has progressed to that covers an estimated 2,500,000 acres (1,000,000 hectares). dangerously high levels in some groves and must be The locations of the groves are influenced by the interaction reduced. The bare mineral soil and open canopy required for of temperature, soil moisture, and site-disturbing events such reproduction must also be re-created. as fire (Weatherspoon 1985). To deal with these problems, in the past 30 years the Giant sequoias are found in 75 areas on land adminis- Forest Service has observed and participated in giant tered by private owners, the USDA Forest Service, Tulare sequoia research conducted by other agencies. Drawing from County, the National Park Service, the Bureau of Land this information, National Forest management of giant Management, the State of California, and the Tule River sequoia has centered on working with the species in its Indian Reservation. Roughly one-half of the naturally different stages of growth, and in developing strategies to occurring groves and one-third of the acres are found in the mitigate the adverse conditions created by fire exclusion Sequoia National Forest. Most of the remaining groves are within the groves. located within the boundaries of Sequoia and Kings Canyon Currently, the Forest Service is exploring research National Parks. opportunities in giant sequoia groves and mapping naturally occurring giant sequoia groves and establishing plans Groves Under National Forest Stewardship for each. It is also developing strategies to continue to incorporate public values and concerns in giant sequoia The Forest Service manages both the extreme northern management. This paper chronicles the parallel evolution of and southern extensions of the giant sequoia's range. The grove management and public values, and points toward a northernmost grove, the Placer County Grove, is located in future where grove management will be guided jointly by the Tahoe National Forest, near Sacramento. The southern- biology and by clear societal preference for preservation of most grove, Deer Creek, is located in the Sequoia National esthetic values. Forest, near Bakersfield. The Sequoia National Forest manages 38 giant sequoia groves throughout the sequoia's southern range (Rundel 1An abbreviated version of this paper was presented at the Symposium on Giant Sequoia: Their Place in the Ecosystem and Society, June 23-25, 1972). According to data in a 1981 forest vegetation inventory, 1992, Visalia, California. these groves cover about 13,200 acres (5,280 hectares). Of 2Regional Forester, Pacific Southwest Region, 630 Sansome Street, these acres, only 3,400 acres (1,360 hectares) are dominated San Francisco, CA 94111; Forest Supervisor, Sequoia National Forest, 900 by an estimated 8,600 specimen trees with a diameter of 8 West Grand Ave., Porterville, CA 93257; District Ranger, Hume Lake Ranger District, 35860 E. Kings Canyon Rd., Dunlap, CA 93621; Silvicul- feet (240 centimeters) or greater. The remaining acres are turist, Sequoia National Forest, 900 West Grand Ave., Porterville. CA characterized as a mixed-conifer forest with young giant 93257--all with USDA Forest Service. sequoias present. No one has estimated the number of smaller 152 USDA Forest Service Gen. Tech. Rep.PSW-151. 1994. giant sequoias, but on the basis of field observations, it is the removal of dead or dying trees and the development of a reasonable to assume they number in the tens of thousands. campground and summer home tract in the McIntyre Grove. The Sierra National Forest has two groves, the Nelder in Other National Forests usually restricted their activities to a northern section of the forest, and the McKinley at the trail and road development. southern edge. The Sierra National Forest Land and Some of the most visible recreation development took Resource Management Plan recommends historical area place in the National Parks. The Park Service developed designation for the Nelder Grove because of its early-day administrative, commercial, residential, and recreational logging record. Current recreation amenities in that grove facilities in some of the giant sequoia groves at Yosemite and include a campground, the Shadow of the Giants National Sequoia National Parks. The most extensive developments Recreation Trail, and a trail to the Bull Buck Tree, one of the were at Giant Forest, in Sequoia National Park. largest giant sequoias in the National Forests. The Sierra From the time the groves were acquired, Federal agencies plan also recommends botanical area designation to promote followed a policy of quickly suppressing all wild fires. As research and ecological study in the McKinley Grove. early as 1955, Herbert Mason, a professor at the University The Tahoe National Forest has one grove that has been of California, writing in the Sierra Club Bulletin, recognized designated the Placer County Big Tree Grove Botanic Area. that fire exclusion was changing the composition of species This is the northernmost grove in the giant sequoia range. in the Sierra Nevada (Mason 1955). Six giant sequoias grow here. The largest is 12 feet (360 In the 1950's and 1960's, both the Forest Service and centimeters) in diameter. Park Service began to notice the effects of the competing In addition to preserving specimen old-growth giant vegetation on giant sequoias. A greater number of trees were sequoias, the Forest Service is planting giant sequoia seed- growing in association with giant sequoias than would have lings outside established groves. These young trees will been expected before wildfires were suppressed. Most of the increase biodiversity, contribute to the esthetic quality of the additional trees were shade-tolerant white fir and forest, and to some extent provide wood and wood products incense-cedar, and natural giant sequoia reproduction was for the future. lacking in most of the groves. Also, large amounts of ground Within the groves, the agency also manages about 3,000 fuels such as duff, brush, and downed logs had developed, acres (1,200 hectares) of second-growth giant sequoias that increasing the potential for fire. are between 60 and 90 years old. This young second-growth is managed for restoration of Vegetative Changes and Reproduction the groves. The Sequoia National Forest contains many examples of Developing an Approach to Giant the connection between vegetative changes and giant sequoia Sequoia Management reproduction. The main causes of change in vegetative structure and diversity are wildfire and historic logging. The history of disturbances of the giant sequoia by Based on Sequoia National Forest fire records, fires within Europeans can be documented as far back as their announced the Forest Service's giant sequoia groves occur at a frequency discovery in 1852 by early settlers (Hartesveldt and others of three to four fires per year. Virtually all are less than 1975). Logging began almost immediately, but did not reach an acre or half a hectare. The interval of larger fires, 3,000 a large scale until about 1890. acres (1,200 hectares) or larger, such as the Daunt Fire (1910- Between 1890 and 1925 at least nine of the then privately Freeman Grove), Deadman Fire (1928-Black Mountain owned groves were logged for nearly all the giant sequoias, Grove), and the McGee Fire (1955-Converse Basin), occur as well as the more valuable pine and fir. A few of the on the average every 20 to 30 years. smaller giant sequoias were also cut in the Nelder grove. Nearly all the young-growth giant sequoias that exist Both the state and federal government recognized the value on private and Federal land resulted from removing the of these unique trees and sought to protect them by acquiring competing trees and digging down to bare mineral soil during land containing the largest and best-known groves. Between early-day logging. A primary example was Converse Basin 1936 and 1975, the Sequoia National Forest acquired all or where the Forest Service acquired land that had been clear-cut portions of the Little Boulder, Converse, Bearskin, Lockwood, while in private ownership.