Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

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

Publication Information

View PDF (503.0 KB bytes)

Title: Long-term structural change in uneven-aged northern hardwoods

Author: Leak, William B.;

Date: 1996

Source: Forest Science. 42(2): 160-165.

Publication Series: Scientific Journal (JRNL)

Description: The diameter distributions of 10 previously unmanaged northern hardwood stands on the Bartlett Experimental Forest in New Hampshire were analyzed to determine changes over a 35 yr period since a single cutting by the diameter-limit or single-tree selection methods. The diameter distribution of an uncut old-growth stand (the Bowl) provided a comparison. The cuttings left residual basal areas of 25 to 96 ft2 of basal area per acre (5.7 to 22.0 m2/ha), as well as a wide range in diameter distribution. Basal area of the old-growth stand was 123 ft2/ac (28.2 m2/ha), and the diameter distribution was reverse J-shaped (negative exponential) as evidenced by a close fit (adjusted r2 = 0.97) of log (no. of trees) over dbh class; the q (ratio between numbers of trees in successive 2 in. dbh classes) equaled 1.39. Under all cutting methods, the diameter distributions after 35 yr fit the reverse J-shaped form only moderately well with adjusted r2's of 0.81 to 0.95. An equal or better fit in most cases (adjusted r2's of 0.91 to 0.98) was provided by log (no. of trees) over dbh2, which reflects the tendency of the quotients between numbers of trees per dbh class to increase with dbh. None of the initial diameter distributions of the cut stands had rotated sigmoid characteristics, but five of the final diameter distributions had significant rotated sigmoid characteristics, and at least two others showed graphical sigmoid tendencies. Apparently, rotated sigmoid characteristics are caused by disturbance, perhaps coupled with successional trends toward increased tolerant softwoods.

Keywords: Diameter-distribution, negative-exponential, rotated-sigmoid, balanced-stand, q-distribution

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.
  • This publication may be available in hard copy. Check the Northern Research Station web site to request a printed copy of this publication.
  • Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact Sharon Hobrla, shobrla@fs.fed.us if you notice any errors which make this publication unusable.

XML: View XML

Citation:


Leak, William B. 1996. Long-term structural change in uneven-aged northern hardwoods. Forest Science. 42(2): 160-165.

 


 [ 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.