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Old Growth Forests Of The Pacific Northwest
Old Growth Forests Of The Pacific Northwest Recent Changes In The World’s Forests • Reduction in total forest acreage • Conversion of naturally structured and regenerated forests to even aged monoculture plantations • Fragmentation Olympic National Park Clear cuts just outside the park boundary Olympic National Forest National forests differ from national parks in that they are multiple use regions. This means that logging, mining, and drilling for oil are allowed on national forest lands. Olympic National Forest – Clear Cuts National Forest Uses “Nonintensive Management” by the forest service in the Sierra Nevada sequoia groves left the three sisters surrounded by a clear cut in Sequoia National Forest. The trees were cut with the stated aim of reducing fire danger and aiding sequoia propagation Each Pair of Spotted Owls Needs As Much As 3,000 Acres of Old Growth for Foraging Earth First Group In Oregon 120 foot 800 year old Red Cedar This Downed Tree Id Worth $10,000 at the Mill. The Logger Earns $175 for Felling 10 – 15 Trees Timber Mill in Oregon Washington: Raw Logs Bound For Orient Logs from Tongrass National Forest, Alaska Project Lighthawk – The goal is to raise public awareness of logging on national forest lands. Vancouver Island Clear Cuts – Tarhgee National Forest just outside Yellowstone National Park Monoculture Tree Plantation Olympic National Park View from trail Near Heart ‘O the Hills Campground Olympic National Park Marymere Falls Characteristics of Old Growth Forests Characteristics of Old Growth Forests Multi-layered Canopy Trees of different sizes and ages Multilayered Canopy of a Tropical Rainforest A view of a tropical rainforest showing a multilayered canopy in Costa Rica Characteristics of Old Growth Forests Snag A snag is a dead standing tree. Shrader Old Growth Trail, Oregon Evidence Of A Cavity Nester Union Creek Trail, Oregon Characteristics of Old Growth Forests Artificial Snags Characteristics of Old Growth Forests Downed Log: Union Creek Trail, Oregon Characteristics of Old Growth Forests Downed Logs • Prevent soil erosion • Create pools in streams which provide habitat for salmon • Act as a nursery bed for conifer seedling • Are quickly colonized by invertebrates such as Ambrosia beetles • Ambrosia beetles carry hitch-hiking fungi, nematodes, and bacteria Downed Logs Downed Logs Act As Nurseries For Tree Seedlings Union Creek Trail, Oregon Downed Logs in Streams Downed logs in streams are vital to the ancient forest ecosystem. They provide habitat for many aquatic animals; they slow the flow of water, easing erosion; they create pools, falls, and riffles, and eddies that fish require; and they slowly release nutrients to the stream community. Logs in Creek: Union Creek Trail, Oregon Old, Large Douglass Firs Characteristics of Old Growth Forests Olympic National Park Abundant shade tolerant tree species. Characteristics of Old Growth Forests Characteristics of Old Growth Forests Epiphytes – Plants that grow on other plants Epiphytes The Cabbage Leaf Lichen: Lobaria • An epiphyte • Has nitrogen fixing bacteria sandwiched between layers of fungus • Constant rain of Lobaria from canopy to forest floor provides the forest ecosystem with over ½ its input of nitrogen What Is A Lichen? • A combination of an algae and a fungus • An example of symbiosis • Types of symbiotic relationships – Parasitism – Mutualism – Commensalism Shaeffer Trail, Oregon Light gaps in the canopy Characteristics of Old Growth Forests Shelf Fungus Union Creek Trail, Oregon Truffles • Top: The truffle of the fungus of Hysterangium coriaceum. Its threadlike hyphae are colonizing a tree rootlet • Bottom: The spores pass unharmed through rodents’ digestive tracts and are thereby widely distributed. The Flying Squirrel • Spends most of its life in trees • Descends to forest floor in search of food • Eats primarily truffles • During spring and summer a typical acre of old growth may harbor as many as 8 pounds of truffles Fungi Red Tree Vole eating a truffle Non-michorrhizal root with root hairs • Fungi vary in form and ecological role. Some secrete enzymes to break down dead tissue. • Others form mycorrhizal links with roots. This enhances the roots ability to absorb moisture and nutrients. Mycorrhizae associated with a tree root Characteristics of Old Growth Forests Mycorrhizal Fungi • Mycorrhizal fungi are associated with the roots of conifers. • They extract minerals and water from the soil and pass it to the tree roots. • These fungi live off sugars produced by their host plant. Northern Spotted Owl • The spotted owl feeds on flying squirrels, wood rats, mice, small birds, bats, and insects. • The northern spotted owl’s habitat is rapidly disappearing due to logging. • The old trees that this species needs for survival take more than 3 centuries to grow. The Pileated Woodpecker Is a Primary Cavity Nester Primary Cavity Nester The Pileated Woodpecker is an important member of healthy older forest communities. This woodpecker excavates nest and roost cavities that are subsequently used by other birds and small mammals. Thus the pileated woodpecker is a keystone species in old growth forests. A keystone species is a species that other animals in the ecosystem depend on for their survival. Secondary Cavity Nesters Mountain Bluebird • These are animals that use cavities abandoned by woodpeckers. • These animals are dependant on primary cavity nesters to build the cavities they nest in. Secondary Cavity Nesters Mountain Bluebird Pygmy Nuthatch • These are animals that use cavities abandoned by woodpeckers. • These animals are dependant on primary cavity nesters to build the cavities they nest in. The Flying Squirrel The Flying Squirrel • Spends most of its life in trees • Descends to forest floor in search of food • Eats primarily truffles • During spring and summer a typical acre of old growth may harbor as many as 8 pounds of truffles Old Growth Forest Roosevelt elk need the tempering microclimate of old growth to get through summer’s heat and winter’s Cold. Snow accumulation is 6 times greater in clearcuts which decreases winter Forage. Clear cuts lack lichens and fungi which important winter forage items Roosevelt Elk - Prairie Creek State Park, CA The Marbled Murrelet • The Marbled murrelet feeds at sea. This is an unusual sea bird because it raises its young in the forest • These birds nest exclusively among the luxuriant mosses and lichens of huge, old trees • Ecologists consider them dependent on old growth Prairie Creek State Park Prairie Creek State Park
