Tongass National Forest

Southeast Alaska Discovery Center
Environmental Exhibits

A Forest of Islands in a Marine Zone

The Alaska Current, an offshoot of the Kuroshio "Drift" that rolls across the North Pacific, bathes Southeast Alaska with warm seas in the winter and cool seas in the summer. This marine ecosystem includes a complex food web rich in plankton, fish, birds and marine mammals, Southeast Alaska's seas are among the world's most diverse ecosystems.

 

 

 

 

 

 

Survival Among the Tides

 

Southeast Alaska's 15,500 miles of coastline form one continuous intertidal ecosystem. Twice a day, tides rise and fall 12 to 20 feet over shores of mud, gravel, cobbles, large boulders or bedrock cliffs. More than 170 species of animals have adapted in remarkable ways to this daily regimen.

 

 

 

 

 

 

Muskegs: Sponges of the Rain Forest

In southeast Alaska, clouds release 4 to 25 feet of rain every year. Muskegs act like giant sponges, slowly absorbing and releasing excess water into streams and rivers. Muskegs have such waterlogged soils that most plant species are slow growing and stunted.

The muskeg's abundance of water, as well as acid, the nature of the water slows decay of dead plants and animals. The trees and plants that survive in the muskeg have special adaptations to its wet and acidic conditions. Shore pine, western hemlock and mountain hemlock grow slowly, taking on stunted, bonsai-like forms, despite significant ages.

The muskeg's open, light meadows attract birds and mammals from the neighboring forest edges for courtship displays or for seeking prey.

 

Streams: Arteries of the Forest

Nutrient-rich streams flow through the forest, always wetlands are the center of biological diversity. Insects and fish breed in pools and eddies and become food for birds and mammals.

Streams are the spawning and breeding grounds for at least one species of Pacific salmon. Some host all five species.

The health of streams and streamside or riparian plants and forests are interwoven. Large, fallen trees help stabilize stream channels. Shrubs and herbs along their banks provide habitat for aquatic insects, birds and mammals. Flooding rivers and decomposing salmon carcasses bring nutrients to adjacent plants. Rotting trees, branches and leaves return nutrients back to the streams.

The Alpine: A Harsh Snow-packed Frontier

To survive the cold winter winds and wet heavy snowpack of alpine ecosystems, hardy plants lie dormant on the mountaintops and exhibit very short blooming and growing seasons. Alpine ridges serve as travel corridors for many animals. In spring and summer, animals roam the lush carpets that bloom in the subalpine meadows. These animals include; mountain goats and wolverine travel across rocky ridges. Deer, marmot, ptarmigan and American pipit browse the mountaintops and meadows in spring and summer for new growth.

Estuary: Fertile Feeding Grounds

Estuaries are places where fresh waters from streams and rivers and salt waters of the ocean meet. They teem with life and are continually bathed in nutrients and sediments from both the temperate rain forests and the oceans. The estuaries' salt marshes, mud flats and sub-tidal zones are a regular, and favored, dining spot. Almost all of southeast Alaska's birds, mammals and fish benefit from the enormous productivity of the estuaries.

 

 

The Ever Changing Temperate Forest

The temperate rain forest of Southeast Alaska has grown up on a harsh, barren bed of glacial till left behind 13,000 years ago by receding glaciers. Seeds for forests drifted in on the winds and in the feces, feathers, and hair of animals initiating plant succession that continues to this day. Old-growth temperate rain forests reached maturity in about 400 years and continued in a steady state for thousands more. Living and decaying at different rates consists of dense patches of trees in a mosaic with streamside, muskeg, and other vegetation types.

 

 

 

 

Trees of the Forest

Alder: Smoked salmon is preferably smoked with alder. The bark was used as a medicine both internally and externally. The wood was carved into fine spoons, bowls, ladles, masks and frontlets.

Hemlock: This hardwood was used to make spoons and ladles. Its sweet inner bark was used as a food sweetener. Hemlock branches were used in collecting herring eggs.

Yellow Cedar: A fine, light softwood, yellow cedar was used for carving masks, headdress frontlets, rattles and bentwood boxes and chests. Its inner bark was used for clothing and baskets.

Red Cedar: Alaska Natives regard red cedar as the most important tree in the forest. Canoes, totems, housing, bentwood boxes and chests, paddles and masks were made from its wood. Its outer bark is used as roofing material and its inner bark is made into baskets, sails, towels, hats and mats.

Sitka Spruce: Heavy roots are woven into large fish traps and bear snares. The lighter roots were dug, roasted, split and woven into all types of baskets. In the Yakutat area, spruce trunks are used as house posts, as cedar doesn't grow there.

Yew: Yew, although rare on the Tongass National Forest, it is favored for halibut hooks, bentwood bowls and weapons. It is also used for its medicinal qualities.

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