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The New Forest

Weyerhaeuser decided to rapidly salvage and reforest eruption-damaged land because every acre plays an important part in supplying the forest products we all use every day. But reforestation is only the beginning of the story about the new forest.

Our philosophy of forest management is based on knowledge of the natural forest and its cycles. We are continuously learning about and improving our understanding of trees, soil, water and life within the forest. Applying the principles of science, we protect natural resources, improve productivity and maintain an indispensable, renewable resource from which we all benefit.


Salvage and recovery operations began immediately after the blast. Much of the downed timber was still usable, but at great risk of being damaged by insects and diseases.

Salvaging timber around Mount St. Helens required paying extra attention to the safety and health of the company's employees. The National Institute for Occupational Safety and Health first conducted a study to assess health hazards of working in the ash. Six months after the blast, full-scale salvage of downed Douglas-fir, hemlock, silver fir, noble fir and western red cedar was ready to begin.

  • More than 1,000 people were involved in the salvage efforts.
  • 600 truckloads of salvaged logs were removed each day during peak summer months.
  • Salvage work continued for nearly two years.
  • 850 million board feet of timber were salvaged from Weyerhaeuser land.
  • The wood saved was enough to build 85,000 new three-bedroom homes.


People need trees. They give us fresh air and clean water. They provide homes for hundreds of wildlife species. They inspire us and enrich us with their beauty. And when carefully managed, trees are a renewable, recyclable and reusable resource.

  • We all use wood. We use wood and products made from wood every day—in homes, other buildings, paper products, furnishings and tools. Ice cream, cosmetics and thousands of other products contain ingredients from trees. Wood is used around the world for cooking and heating.
  • Wood is good for communities. Well-managed forests provide living-wage jobs and tax revenue for many rural communities.
  • Wood is a great insulator. Wood insulates better than either steel or aluminum. In addition, it requires much less energy to manufacture wood products than non-renewable resources.


  • On average, North Americans use wood and paper products equivalent to one 100-foot tall tree each year.
  • In 60 years of growing, an average tree accumulates 5,250 pounds of organic material through the miraculous use of sun, soil, water and air.
  • A tree exhales 6,000 pounds of oxygen in its life, or about 120 pounds per year, assuming a 50-year life.
  • Each person needs one pound of oxygen to breathe per day, which is 365 pounds per year.
  • One second-growth Douglas-fir takes up about 60 pounds of carbon dioxide per year.
  • Burning one gallon of gasoline produces 19 pounds of carbon dioxide.



Weyerhaeuser harvests only 2 to 3 percent of its Northwest timberland each year, generally when trees are 40 to 60 years old. These levels provide the income needed for future investments, stability to communities, and diverse forest habitat for plant and wildlife. We use a variety of forest management techniques, including:

  • Clearcutting—Most of the trees in an area are harvested at the same time. Clearcutting is especially effective for trees growing west of the Cascade Mountains such as Douglas-fir, which does not tolerate shade and cannot thrive under a forest canopy.
  • Selective cutting—The periodic harvest of single trees or groups of trees creates gaps in the forest, providing space for seedlings that don't need full sunlight.
  • Engineering and planning—Long-term and short-term planning for a forest is a complex task. Technology, such as geographic information systems and satellites have increased the accuracy of information. Forest engineering includes tracking forestry activities, selecting stands for harvest, maintaining roads, determining regeneration requirements and obtaining governmental permits and approvals.


Weyerhaeuser began in 1900 and has since become a world leader in forest management. In 1941, the company started the first certified tree farm in North America. We built upon our planting practices that we use throughout our forests to help with the successful reforesting of Mount St. Helens:

  • Site preparaton—by exposing mineral soil needed for seedling production, survival and growth; protecting the soil from erosion; and reducing the possibility of wildfire.
  • Select the best seedlings—from superior-quality trees for improved production.
  • Plant quickly—targeting almost every harvested area within 12 months of harvest.
  • Choose species wisely—use Douglas-fir and red alder in lowlands, noble fir at elevations above 2,800 feet, and western red cedar, grand fir and hemlock in selected locations.

Replanting the forest makes good business sense, since it assures that forests will be available for human use in the future. In addition, laws in Washington and Oregon have required regeneration of harvested areas on both state and private land since the early 1970s. Most forest owners began replanting logged areas long before required by law, and today most exceed legal standards.


We take good care of young trees after they are planted.

  • Pruning—Trimming lower limbs when a tree is still small helps produce high-quality, knot-free wood. This "clear" wood is used where appearance counts — in furniture, molding and lumber. Cut limbs are left to decay and enrich the soil.
  • Thinning—Removing selected trees from the forest reduces competition for water, nutrients and sunlight. We thin some trees between 25 and 40 years old, when they are large enough to produce lumber and wood chips. This generates some income during the forest's growth cycle.
  • Fertilizing—In the Northwest, we fertilize most trees three times over a 40- to 60-year period to enhance growth and improve health. Other plants that provide diversity and wildlife habitat also benefit. We are careful to keep fertilizers out of streams and other bodies of water.


Effective forest management includes protecting forests from fire, insects, disease and excessive animal damage. We combat fires with aerial surveys, quick-response teams and equipment such as tanker trucks and helicopters. Managing forests requires being prepared for natural events beyond our control, including wildfires, windstorms, floods and (of course) volcanic eruptions.

Besides trees, we protect all parts of the forest ecosystem. We also work closely with tribal groups and governmental agencies to preserve cultural, historic, scenic and recreation areas.

  • Wildlife—When harvesting, we leave a specified number of snags, live trees and downed logs. This may look messy. But it provides food and cover for forest creatures.
  • Fish—To protect spawning beds and keep streams clean we now design, build and maintain roads to very high standards. Some roads are closed or relocated to reduce impacts on streams. We leave forested buffer zones to protect rivers, lakes, streams, springs and ponds where fish can spawn.
  • Watersheds—We analyze entire watersheds in cooperation with other landowners to assess the combined effects of land uses on fish habitat and water quality. This helps us develop land management plans to protect natural resources.


There are two main approaches to managing a devastated forest area like Mount St. Helens. Each has its own goals, results and importance to society.

View additional devastation and regeneration images in our Photo Gallery.

1. Create a "biological laboratory," and let nature take its course. The U.S. Congress established a National Volcanic Monument on federal land around the mountain, to be managed by the U.S. Forest Service. Click here to learn more.
2. Assist nature to regenerate the forest by planting new seedlings, and work hard to restore the area to pre-blast conditions. Weyerhaeuser chose this approach, drawing on science and decades of forest management experience.


In 1982, Congress established the Mount St. Helens National Volcanic Monument. It includes 110,000 acres of devastated land, unique caves and old growth forests. The U.S. Forest Service manages the land for research, recreation and interpretation.

Scientists have learned important lessons from the "biological laboratory" at Mount St. Helens. They have discovered that nature rarely destroys everything. It leaves behind a legacy with remains of the old forest. Examples include snags that provide homes for birds, or young trees that survived because they were protected under snow.

Also, the forest succession was not what textbooks predicted. Instead of a natural order with some species following others, everything came back at once and is now competing for space. This is changing the way we think about forest succession after large-scale disasters.

Since the view at right is a live image of the crater, you may not be able to see anything if it is dark or overcast in the Pacific Northwest.

View the USFS VolcanoCam page.

Image courtesy United States Forest Service.


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These are but a few of the hundreds of species that have returned to our forests around Mt. St. Helens.

Last updated May 21, 2014