Maybeso Experimental Forest
Experimental Forest, located on Prince of Wales Island in southeast
Alaska near Ketchikan, was established in 1956 to investigate the
effects of clearcut timber harvesting on forest regeneration and
regrowth, and on the physical habitat of anadromous salmonid spawning
areas. The watershed was exposed to the first large-scale industrial
clearcut logging in southeast Alaska and nearly all commercial forest
was removed from the watershed, including the riparian zone, from
1953 through 1960. The present forest is an even-aged, second-growth
spruce and hemlock forest.
watershed is a broad U-shaped glacially sculpted valley with a single
stream network. The stream flows through a floodplain composed of
glacial till up to headwater tributaries to an elevation of 900
m. The area of the watershed is approximately 4,452 ha. Pink, chum,
and coho salmon, and Dolly Varden, steelhead, and cutthroat trout
are present throughout the main stream and tributaries. Wildlife
species include several mammals and a variety of resident and migrant
birds. Mammals include Sitka black-tailed deer, black bear, beaver,
American marten, ermine, northern flying squirrel, Keen’s mouse,
long-tailed vole, dusky shrew, and several species of bats. Forest
and riparian birds include bald eagle, northern goshawk, and several
species of owls, chickadees, wrens, warblers, and thrushes. Other
birds found in the watershed are Steller’s jay, northwestern crow,
raven, and spruce grouse. The species assemblages are representative
of a second-growth forest in a temperate rainforest ecosystem.
The proximity of other watersheds in various stages of forest succession on Prince of Wales Island contributes to
the significance of the Maybeso. The Old Tom Research Natural Area (an old-growth forested watershed) is
located in nearby Skowl Arm and is accessible by boat or float plane. It can provide an old-growth control for
some aspects of studies in the Maybeso. Current research in the watershed is focused on studies to provide
information on the management of second-growth watersheds and for the development and evaluation of
watershed restoration methods.
The Maybeso is part of a temperate rain forest and is characterized by cool, moist climate. The mean annual
temperature is 6.7 °C and the average rainfall is about 2,740 mm annually. Temperatures rarely exceed 21 °C
during the summer and seldom drop below -12 °C in the winter. Peak rainfall and streamflows generally occur
during October and November and during the spring in April and May.
More than 90 percent of the valley soils are Tolstoi or Karta. The former are well drained and range from
Entisols to Spodosols developed on steep slopes covered by colluvium on fractured bedrock; the latter are welldeveloped
Spodosols. These form the weathered portion of the compact glacial till of much of the valley.
Sitka spruce and western hemlock are the dominant conifers. Other conifers include Alaska cedar and
mountain hemlock. Red alder is the most common deciduous tree in the watershed. Common shrubs are
Sitka alder, devil’s club, stink and trailing black currant, The Maybeso Experimental Forest (Alaska)
salmonberry, blueberry, winterberry, and scarlet elder. More than 25 percent of the watershed was logged from
1953 through 1960. Nearly all of the commercial forest was harvested and most of the present forest is 40 to 50-
year-old, second-growth Sitka spruce or western hemlock. Alder is the dominant tree species in landslide
tracks, abandoned roads, and parts of the riparian zone.
Long-Term Data Bases
A set of scale maps of the stream was completed and updated annually from 1949 through 1960. Secondgrowth
thinning plots established shortly after timber harvest are remeasured periodically. Juvenile salmonid
populations have been sampled periodically from the early 1980s to the present. Discharge and temperature
records were made from 1949 through 1963 for most months; however, measurements were made only from
April to October from 1948 through 1952.
Research, Past and Present
The Maybeso research program is designed to evaluate aspects of forest regeneration, riparian succession and
evolution of stream channel morphology, and response of salmonid populations to changes in large-wood density
and distribution. Several of these studies cover a period of more than 40 years. During the past 20 years, research
on the watershed has evolved from studies of salmonid spawning habitat to broader studies of stream and
riparian habitat as it moves through succession following timber harvest. The focus has been on changes in stream
habitat as it relates to large-wood and its effect on juvenile salmonid populations. These studies have
established a long-term (> 40-year) analysis of stream channel evolution. An extensive and thorough investigation
of slope stability was conducted and completed during and shortly after logging in the watershed, as was an
analysis of the geology of the watershed. These studies have continued intermittently during the past 30 years.
Plots to evaluate long-term growth and silviculture treatments on the second-growth forest are located
throughout the watershed. Streamflow and temperature data also have been collected intermittently during the
past 40 years. Recent research in the watershed has emphasized land-management activities on steeper slopes
and the role of alder in forest productivity.
Major Research Accomplishments and Effects On Management
Research on the Maybeso watershed has focused on hydrology, slope stability, silviculture, and fish habitat.
Results from research have contributed to guides for timber harvest practices on steep slopes, thinning regimes
for second-growth spruce forests, and management of large-wood in streams.
Researchers from the following institutions have collaborated on studies at the Maybeso: University of
Washington, University of Alaska, Michigan State University, University of Michigan, Montana State
University, Oregon State University, and University of British Columbia.
There are opportunities for research on the following topics:
- Second-growth forest succession
- Effects of intensive silviculture of forest and watershed succession and ecology
- Watershed restoration
A 12-person bunkhouse was completed in 2002 at Hollis; two other older buildings there provide storage
and work space. The facilities at Hollis are located about 3 km from the Maybeso.
Lat. 55° 29' 13" N, long. 132° 39' 59" W
Maybeso Experimental Forest
USDA Forest Service
Pacific Northwest Research Station
Juneau Forestry Sciences Laboratory
2770 Sherwood Lane Suite 2A
Juneau, AK 99801-8545
Tel: (907) 586-8811
1Information has been updated since original publication.