Environmental Engineering Reference
In-Depth Information
structed under the premise that natural services are
free. We can't afford that luxury any more.”
Why have we not changed our accounting system
to reflect these losses? One reason is that the eco-
nomic savings provided by conserving forests (and
other parts of nature) benefit everyone now and in
the future, whereas the profits made by exploiting
them are immediate and benefit a relatively small
group of individuals. A second reason is that many
current government subsidies and tax incentives sup-
port destruction and degradation of forests and other
ecosystems for short-term economic gain. Also, most
people are unaware of the value of the ecological ser-
vices and income provided by forests and other parts
of nature.
Another way to encourage sustainable use of
forests is to establish and use methods to evaluate tim-
ber that has been grown sustainably, as discussed next.
developed by the Forest Stewardship Council (FSC).
Home Depot, Lowes, Andersen, and other major sell-
ers of wood products in the United States have also
agreed to sell only wood certified as being sustainably
grown by independent groups such as the FSC (to the
degree that certified wood is available).
8-4 FOREST RESOURCES
AND MANAGEMENT IN THE
UNITED STATES
U.S. Forests: Encouraging News
U.S. forests cover more area than they did in 1920,
more wood is grown than is cut, and the country has
set aside large areas of protected forests.
Forests cover about 30% of the U.S. land area, provid-
ing habitats for more than 80% of the country's
wildlife species and supplying about two-thirds of the
nation's total surface water.
Good news.
Forests (including tree plantations) in
the United States cover more area than they did in
1920. Many of the old-growth forests that were cleared
or partially cleared between 1620 and 1960 have
grown back naturally through secondary ecological
succession as fairly diverse second-growth (and in
some cases third-growth) forests in every region of the
United States, except much of the West. In 1995, envi-
ronmental writer Bill McKibben cited forest regrowth
in the United States—especially in the East—as “the
great environmental story of the United States, and in
some ways the whole world.”
Every year more wood is grown in the United
States than is cut, and each year the total area planted
with trees increases. By 2000, protected forests ac-
counted for 40% of the country's total forest area,
mostly in the national forests (Figure 5-19, bottom,
p. 93).
Bad news.
Since the mid-1960s, an increasing area
of the nation's remaining old-growth and fairly di-
verse second-growth forests has been clear-cut and
replaced with biologically simplified tree plantations.
According to biodiversity researchers, this practice re-
duces overall forest biodiversity and disrupts eco-
system processes such as energy flow and chemical
cycling. Some environmentally concerned citizens
have protested the cutting down of ancient trees and
forests (see Individuals Matter, p. 166).
Solutions: Certifying Sustainably
Grown Timber
Organizations have developed standards for
certifying that timber has been harvested sustainably
and that wood products have been produced from
sustainably harvested timber.
Collins Pine owns and manages a large area of produc-
tive timberland in northeastern California. Since 1940,
the company has used selective cutting to help main-
tain the ecological, economic, and social sustainability
of its timberland.
Since 1993, Scientific Certification Systems (SCS)
has evaluated the company's timber production. SCS,
which is part of the nonprofit Forest Stewardship
Council (FSC), was formed to develop a list of environ-
mentally sound practices for use in certifying timber
and products made from such timber.
Each year, SCS evaluates Collins Pine's landhold-
ings to ensure that cutting has not exceeded long-term
forest regeneration, roads and harvesting systems
have not caused unreasonable ecological damage, soils
are not damaged, downed wood (boles) and standing
dead trees (snags) are left to provide wildlife habitat,
and the company is a good employer and a good stew-
ard of its land and water resources.
In 2001, the Worldwide Fund for Nature (WWF)
called on the world's five largest companies that har-
vest and process timber and buy wood products to
adopt the FSC's sustainable forest management princi-
ples. According to the WWF, doing so would halt vir-
tually all logging of old-growth forests yet still meet
the world's industrial wood and wood fiber needs us-
ing one-fifth of the world's forests.
In 2002, Mitsubishi, one of the world's largest
forestry companies, announced that third parties
would certify its forestry operations using standards
Science: Fires and U.S. Forests
Forest fires can burn away flammable underbrush and
small trees, burn large trees and leap from treetop to
treetop, or burn flammable materials found under the
ground.
