Journal
FIRE ECOLOGY
Volume 6, Issue 3, Pages 62-76Publisher
ASSOC FIRE ECOLOGY
DOI: 10.4996/fireecology.0603062
Keywords
California; ecological restoration; fire exclusion; fire suppression; fire regimes; forest stand dynamics; Klamath Ecoregion; old-growth forest; ponderosa pine; stand structure
Funding
- Department of the Interior [J8485 05 0065, H8480 01 0009]
- National Park Service [J8485 05 0065, H8480 01 0009]
- Redwood National Park [J8485 05 0065, H8480 01 0009]
- Humboldt State University Foundation [J8485 05 0065, H8480 01 0009]
Ask authors/readers for more resources
The rare relict ponderosa pine (Pinus ponderosa C. Lawson) mixed-conifer forests of northern California's Whiskeytown National Recreation Area (WNRA), USA, present a classic example of fire exclusion. Altered fire regimes in this biologically unique area have been documented, but the resulting changes in forest composition and structure have not previously been described. A fully randomized, park-wide sampling of relict forest structure at WNRA reveals a high degree of topographic variability in tree species composition, but strikingly similar changes in recent structural development. A distinct cohort of encroachment trees initiated approximately 64 yr to 67 yr ago with little age variation (2 yr SE), with distinct strata now distinguishing the relict and encroachment cohorts. Over the past five decades, the average periodic annual basal area growth of relict trees has remained at a virtual constant of 24 cm(2) to 27 cm(2) per tree. In contrast, the annual basal area increment of encroachment trees has been steadily increasing, from 3 cm(2) per tree in 1955 to 16 cm(2) per tree in 2005. Whereas relict trees are comprised primarily of pine species (76%), they represent just 17% of encroachment trees. In contrast, white fir, Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco.), and tanoak (Lithocarpus densiflorus [Hook. & Arn.] Rehder) are rare among relicts (16%) but are the most predominant species among encroachment trees (64%). This study's findings should inform the planning of restoration activities to reduce threats to relict forests at the WNRA as well as similar forests in the southeastern Klamath Mountains.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available