Maintaining Terrestrial Biomes In the United States, the government manages public lands including forests, parks, and refuges. Their use varies from resource extraction to farming to recreation. Multiple use lands include those in the National Forest System Managed by the U.S. Forest Service National Resource Lands Managed by the Bureau of Land Management National Wildlife Refuges Managed by the U.S. Fish and Wildlife Service Permitted activities include: logging mining oil and gas extraction livestock grazing farming recreation How should they be managed? Who should be permitted to use the lands? Ongoing controversy Examples: Northern Spotted Owl Endangered species Habitat: Old-growth forests Of pacific northwest Versus: Jobs and harvesting resources: the old- growth trees are of high commercial value Should we drill baby drill??? ANWR Some public lands are restricted in use National Park System Managed by the National Park Service (NPS) First established National Park??? Only camping, hiking, fishing, and boating (motorized cars/boats are allowed) Yosemite The Grand Canyon Denali Arches Volcano Carlsbad Caverns Big Bend Glacier The Badlands Great Smokey Mountains Other public lands are very restricted meant to be preserved in their natural condition National Wilderness Preservation System Established by the Wilderness Act (1964) Managed by multiple agencies (BLM, USFWS, USFS, and NPS) National Wild and Scenic Rivers (1968) Non-motorized recreation ONLY Types of Forests: Old-growth: has not been cut/disturbed by human activity for hundreds of years. Example: Redwood Forest Second-growth: forest that has grown back after it had been cut/removed by human activities. Since 1600, 90% of the virgin forests that once covered much of the lower 48 states have been cleared away. Most of the remaining old-growth forests in the lower 48 states and Alaska are on public lands. In the Pacific Northwest about 80% of this forestland is slated for logging. Global Deforestation Lecture, The University of Michigan: Global Change Tree plantation or tree farm: Monoculture (example: Christmas tree farm) (example: apple orchard) Types of Forest Management: Even-aged: Maintaining trees at about the same age and size (tree plantation) Goal: economically desirable species Uneven-aged: Maintaining a variety of trees at many ages and sizes Goal: sustainable production Types of Tree Harvesting: Selective cutting: medium or mature trees in uneven-aged stand cut singly or in small groups. Shelterwood cutting: remove all mature trees in an area in a series of cuttings. First cut: mature trees (mostly canopy trees) Second cut: more mature canopy trees but leaves a few mature trees to shelter the young trees (which are shade tolerant) Third cut: remove remaining mature trees now that the younger ones are growing to maturity Seed-tree cutting: harvesting nearly all trees in one cutting, but leaving a few uniformly distributed seedlings. Strip cutting: removes all trees in an area in a single cutting (in a strip) Clear cutting: removes ALL trees in a single area. MOST devastating to an ecosystem; causes massive soil erosion if done on sloped land. Types of Forest Fires Surface: Usually burn only undergrowth and leaf litter on forest floor. Ground: surface fire that goes underground (most common in areas that contain peat northern peat bogs). Difficult to detect and extinguish. (peat bog) Crown: May start on ground but eventually burn up whole tree and leap tree-top to tree-top. MOST DANGEROUS! Prescribed burning: Controlled burning of flammable materials to prevent build-up of fire-prone debris. Used to prevent major fires in populated areas, but remember, not all fire is bad some plants and even biomes need fire to regenerate. Grasslands and Chaparral Aspen trees in Yellowstone Healthy Forests Initiative (HFI): Passes by Congress in 2003 Timber companies are allowed to cut down economically valuable large trees in return for clearing away fire-prone underbrush. Removes large, more fire-resistant trees. Leaves fire-prone slash: unwanted branches, tops, stumps.