Post on 30-May-2020
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 ForestNational forests differ from national parks in that they aremultiple use regions. This meansthat logging, mining, and drillingfor oil are allowed on national forest lands.
Olympic National Forest – Clear Cuts
National Forest Uses
“Nonintensive Management” bythe forest service in the SierraNevada sequoia groves left the three sisters surrounded by a clearcut in Sequoia National Forest. The trees were cut with the statedaim of reducing fire danger andaiding 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 oldRed 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 loggingon national forest lands.
Vancouver Island
Clear Cuts –Tarhgee NationalForest just outsideYellowstoneNational Park
Monoculture Tree Plantation
View from trail Near Heart ‘O the Hills Campground
OlympicNational
Park
Marymere Falls
OlympicNational
Park
Characteristics of Old Growth Forests
Multi-layered Canopy
Trees of different sizes and ages
Characteristics of Old Growth Forests
Multilayered Canopy of a Tropical Rainforest
A view of a tropicalrainforest showing a multilayered canopy in Costa Rica
SnagA snag is a dead standing tree.
Shrader Old Growth Trail, Oregon
Characteristics of Old Growth Forests
Evidence Of A Cavity Nester
Union Creek Trail,Oregon
Characteristics of Old Growth Forests
Artificial Snags
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
Characteristics of Old Growth Forests
Downed Logs
Downed LogsAct 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
Abundant shade tolerant tree species.
OlympicNational
Park
Characteristics of Old Growth Forests
Epiphytes – Plants that grow on other plants
Characteristics of Old Growth Forests
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 FungusUnion Creek Trail,Oregon
Truffles
• Top: The truffle of the fungus of Hysterangium coriaceum. Its thread- like 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
• 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 rootNon-michorrhizal root with root hairs
RedTreeVoleeating atruffle
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.
Characteristics of Old Growth Forests
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 PileatedWoodpeckerIs a PrimaryCavity 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
• These are animals that use cavities abandoned by woodpeckers.
• These animals are dependant on primary cavity nesters to build the cavities they nest in.
Mountain Bluebird
Secondary Cavity Nesters
• These are animals that use cavities abandoned by woodpeckers.
• These animals are dependant on primary cavity nesters to build the cavities they nest in.
Mountain Bluebird
PygmyNuthatch
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 GrowthForest
Roosevelt elk need the tempering microclimate ofold growth to get throughsummer’s heat and winter’s Cold.
Snow accumulation is 6times greater in clearcutswhich decreases winterForage.
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 CreekState Park
Prairie Creek State Park