Skip to page content
USDA Forest Service

Research & Development Treesearch

Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help - We Participate  Government Made Easy

Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (411 KB bytes)

Title: Stand conditions associated with tree regeneration in sierran mixed-conifer forests.

Author: Gray, Andrew N.; Zald, Harold S.J.; Kern, Ruth A.; North, Malcolm.;

Date: 2005

Source: Forest Science. 51(3): 198-210

Publication Series: Scientific Journal (JRNL)

Description: Fire suppression has significantly increased canopy cover, litter depth, and stem density in many western forests, altering microsite conditions that affect tree seedling establishment. We conducted studies in a mixed-conifer forest in the Sierra Nevada, California, to determine relationships between established understory trees and microsite quality, and to examine the effect of fire intensity and shrub cover on seedling establishment. Most of the conifer species were found on microsites with relatively high soil moisture and relatively low direct solar radiation. All species had greater frequency under shadier conditions except for Jeffrey pine, which was found on drier, more open microsites. Although seedlings were more abundant on mineral soil than expected, intact litter and forest floor was not a barrier to establishment. Mortality of planted seedlings was high, particularly in exposed areas. Although shrub cover may initially aid survival, few conifer saplings were present in shrub-dominated patches, possibly because shrubs can be aggressive competitors for soil moisture. The lack of regeneration, logs, or snags in many openings suggest that large gaps are hostile environments for tree seedlings. Results suggest that reductions in shrub cover may benefit tree establishment, but increasing understory light and decreasing surface soil moisture through canopy cover reductions may not.

Keywords: natural regeneration, microclimate, fire, shrub competition, old-growth, Abies concolor, Abies magnifica, Calocedrus decurrens, Pinus jeffrey, Pinus lambertiana, Prunus emarginata, Quercus kelloggii, Ceanothus cordulatus, Arctostaphylos patula

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.



Gray, Andrew N.; Zald, Harold S.J.; Kern, Ruth A.; North, Malcolm. 2005. Stand conditions associated with tree regeneration in sierran mixed-conifer forests. Forest Science. 51(3): 198-210


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.