Page:United States Statutes at Large Volume 114 Part 6.djvu/231

 PROCLAMATION 7295—APR. 15, 2000 114 STAT. 3287 scape, and historic remnants of early Eiiroamerican settlement as well as the commercial exploitation of the giant sequoias. The monument provides exemplary opportunities for biologists, geologists, paleontologists, archaeologists, and historians to study these objects. Ancestral forms of giant sequoia were a part of the western North American landscape for millions of years. Giant sequoias are the largest trees ever to have lived, and are among the world's longest-lived trees, reaching ages of more than 3,200 years or more. Because of this great longevity, giant sequoias hold within their tree rings multi-millennial records of past environmental changes such as climate, fire regimes, and consequent forest response. Only one other North American tree species, the high-elevation bristlecone pine of the desert mountain ranges east of the Sierra Nevada, holds such lengthy and detailed chronologies of past changes and events. Sequoias and their surroimding ecosystems provide a context for understanding ongoing environmental changes. For example, a century of fire suppression has led to an unprecedented failure in sequoia reproduction in otherwise imdistuj'bed groves. Climatic change also has influenced the sequoia groves; their present highly disjimct distribution is at least partly due to generally higher siunmertime temperatures and prolonged summer droughts in California from about 10,000 to 4,500 years ago. During that period, sequoias were rarer than today. Only following a slight cooling and shortening of summer droughts, about 4,500 years ago, has the sequoia been able to spread and create today's groves. These giant sequoia groves and the surrounding forest provide an excellent opportunity to understand the consequences of different approaches to forest restoration. These forests need restoration to counteract the effects of a century of fire suppression and logging. Fire suppression has caused forests to become denser in many areas, with increased dominance of shade-tolerant species. Woody debris has accumulated, causing an imprecedented buildup of surface fuels. One of the most immediate consequences of these changes is an increased hazard of wildfires of a severity that was rarely encountered in pre- Euroamerican times. Outstanding opportunities exist for studying the consequences of different approaches to mitigating these conditions and restoring natural forest resilience. The great elevational range of the monument embraces a number of climatic zones, providing habitats for an extraordinary diversity of plant species and communities. The monument is rich in rare plants and is home to more than 200 plant species endemic to the southern Sierra Nevada mountain range, arrayed in plant communities ranging from low-elevation oak woodlands and chaparral to high-elevation subalpine forest. Numerous meadows and streams provide an interconnected web of habitats for moisture-loving species. This spectrum of interconnected vegetation types provides essential habitat for wildlife, ranging from large, charismatic animals to less visible and less familiar forms of life, such as fungi and insects. The midelevation forests are dominated by massive conifers arrayed in a complex landscape mosaic, providing one of the last refugia for the Pacific fisher in California. The fisher appears to have been extirpated from the northern Sierra Nevada mountain range. The forests of the monument are also home to great gray owl, American marten, northern gos-

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