|Abstract or Summary
- Douglas-fir (Pseudotsuga menziesii) has a wide distribution in North America and is one of the
tree species most widely distributed outside its natural range. The species has been introduced to
Europe, New Zealand, South America, and elsewhere around the world. At present, Douglas-fir
is an accepted and integral part of forest management in many countries because of its economic
importance and its reputation as a species that may be able to deal with climate change.
This book provides an overview of research activities and findings that highlight unique aspects of
Douglas-fir physiology, genetics, and other related issues. It begins with the evolutionary history
and distribution of Douglas-fir and provides a detailed description of introductions of Douglas-fir
to other countries, including information about initial plantings, provenance trials, and genetic
tree improvement activities.
The sections about life history, drawn from extensive research and teaching experiences, include
detailed descriptions of flowering, seeds, root, and seedling physiology, followed by sections about
mycorrhizae and insects, diseases, and other biotic factors. It discusses research that demonstrates
the some unique aspects of Douglas-fir physiology, for example: (1) Douglas-fir has an annual
growth cycle that includes a cold period in the late fall or early winter. Failure to experience these
low temperatures results in a substantial loss of vigor; (2) The reproductive system of the stem is
stimulated by material from the roots; and (3) The root system plays a supportive role. Nutrient
and moisture uptake are mediated by mycorrhizae.
This book is intended as a resource for everyone interested in understanding the opportunities and
challenges of managing Douglas-fir in a variety of regions and settings. It provides information for
historians and social scientists trying to understand forestry trends, researchers, educators, and
managers who look for detailed information in areas such as genetics and regeneration practices,
and all others interested in the beautiful trees we call Douglas-fir.