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from www.forestryimages.org | | Tools and LinksManagement Forest Type Descriptions Forest Health General Resources Discussion ^
The coastal forests of California support some of the most famous trees in the world. The redwood, Sequoia sempervirens, is the tallest tree species and many redwood stands are protected as national treasures. Many other redwood forests have been managed for both social and ecological values.
Redwood forests also include Douglas fir (Psuedotsuga menzisii),, tan oaks (Lithocarpus densiflorus), and California bay laurel (Umbellularia californica). Redwoods are well adapted to disturbance and can regenerate in full sun or partial shade (Busing and Fujimori 2002). Craig Blencowe, a Guild Forester, has been practicing ecological forestry in redwoods for decades based on uneven aged management (Blencowe 2006).
A new threat for redwood is an introduced, generalist pathogen called Phytophthora ramorum. P. ramorum is also the causal agent of sudden oak death. It is still unclear how P. ramorum may affect redwood forests but it has potential to cause mortality and instigate a change in forest composition (Maloney et al. 2005).
Silviculture ^ Some silviculturalists suggest a distinction between redwoods that grow on alluvial flats and those that grow on steep hillsides in mixture with Douglas fir, Sitka spruce grand fir, western hemlock, western red cedar, and Port-Orford cedar (Helms 1980). Most of the redwood groves on alluvial flats are now part of protected areas such as Redwood National Park. Therefore, most management focuses on redwood in mixed forests on steep slopes. In these mixed forests, redwood sprouts compete with tan oak sprouts, and Douglas fir seedlings at stand initiation (Helms 1980). Hardwoods can often overtop the redwoods for the first 70 or 80 years after which point redwoods and Douglas fir dominate the canopy (Helms 1980).
Redwoods grow can quickly. By 100 years old (age measured at breast height), they reach 148 ft tall on a site index of 100 (Hanson et al. 2002). Basal area in unmanaged stands can be as high as 1,000 ft2 per acre and volumes can reach 19,000 ft3 per acre on site index 100 (Helms 1980).
Much of the logging previously focused on old growth stands. Now more sustainable practices are used in second or third growth stands. Competition from hardwoods can be a problem in mixed, hillside stands (Helms 1980). References ^ Busing, R. T., and T. Fujimori. 2002. Dynamics of composition and structure in an old Sequoia sempervirens forest. Journal of Vegetation Science 13(6):785-792. http://dx.doi.org/10.1658/1100-9233%282002%29013%5B0785:DOCASI%5D2.0.CO;2
Hanson, E. J., D. L. Azuma, and B. A. Hiserote. 2002. Site Index Equations and Mean Annual Increment Equations for Pacific Northwest Research Station Forest Inventory and Analysis Inventories, 1985-2001. US Forest Service, Pacific Northwest Research Station. PNW-RN-533. http://www.fs.fed.us/pnw/pubs/rn533.pdf
Helms, J. 1980. The California Region. Pages 391-446 in J. Barrett, editor. Regional Silviculture of the United States, 2nd Ed. John Wiley and Sons, New York, NY.
Maloney, P. E., S. C. Lynch, S. F. Kane, C. E. Jensen, and D. M. Rizzo. 2005. Establishment of an emerging generalist pathogen in redwood forest communities. Journal of Ecology 93(5):899-905. http://dx.doi.org/10.1111/j.1365-2745.2005.01031.x |
