The Fall of Giants: Old-Growth Trees in the American West

Wildlife & Ecosystems

The Fall of Giants: Old-Growth Trees in the American West

In the Western U.S., some of the world's oldest and tallest trees are dying, and at higher rates than in the recent past. But why?

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The facts

Why the research is important

Why the research is important

Results from this study could help land managers preserve existing old-growth forests, make forests more resilient in the future, and even help us regenerate old-growth conditions more rapidly. 

Large-diameter trees have lived for centuries, withstanding fires, wet and dry periods, lightning and wind, and insects. Now, they seem to be in decline, and scientists are trying to find out why. 

Trees in forests worldwide may be dying at higher rates than in the recent past and climate change is thought to be driving this trend. But to understand what is truly happening in these forests, scientists need a massive amount of data, collected over many years, to "ground truth" their hypotheses on the effects of a changing climate. That's where you come in.


By tracking the fate of trees, scientists aim to better understand whats happening in the forest so they can predict future changes.

As part of the investigative team, you'll learn how to conduct pathology exams on "tree corpses" to understand their cause of death. In some areas, for example, trees may be more crowded together and therefore competing over limited resources. In other areas, pathogenic fungi or beetles could be killing otherwise uncrowded trees. Help to determine how the forest is changing and how these changes relate to its very structure as well as changes in climate.

The project will also support the conservation and management of forests by increasing awareness of the services provided by old-growth forests and the large, old trees that exist within them. Research results will be communicated to land managers and may help to inform National Park Service and Forest Service policies.

About the research area

Yosemite National Park, California or Forests of southwest Washington, United States, North America & Arctic

Daily life in the field


This is a summary:

The Scientists


James A.
Assistant Professor, Forest Ecology, Utah State University

ABOUT James A. Lutz

Dr. Jim Lutz is the Principal Investigator of the Western Forest Initiative and Assistant Professor of Forest Ecology at Utah State University. Jim studies the ecosystems of western North America to contribute to science-based conservation and management of our natural resources in the face of changing climate and demography.



Accommodations and Food

Accommodations and Food


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