Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Relationship between treefall direction, slope-aspect, and wind in eight old-growth oak stands in the Central Hardwood Forest, USA

James S. Rentch
The Journal of the Torrey Botanical Society
Vol. 137, No. 4 (OCTOBER-DECEMBER 2010), pp. 391-400
Published by: Torrey Botanical Society
Stable URL: http://www.jstor.org/stable/25790860
Page Count: 10
  • Read Online (Free)
  • Download ($10.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Relationship between treefall direction, slope-aspect, and wind in eight old-growth oak stands in the Central Hardwood Forest, USA
Preview not available

Abstract

This study examined the relationship between direction of treefall, slope-aspect and prevailing wind in five old-growth stands where single-tree canopy gaps characterize the dominant disturbance regime. All live and downed trees were inventoried in 0.45-ha sample plots, and crown sizes of live trees were measured along two perpendicular axes. Directions of fall and slope-aspect of downed trees also were recorded. Regional prevailing winds and wind gusts were obtained from four nearby airports. I used circular statistics to determine if directions of treefall for each study stand had a mean direction or if the directions of fall were uniformly distributed. If directions of treefall had a true mean, they were then compared to mean slope aspect and prevailing wind directions. At two of eight plots, treefall directions were uniformly distributed (i.e., no mean direction). Only one plot showed a statistically significant similarity between mean slope-aspect and mean direction of fall, and only three of the eight study plots showed statistically significant similarities between mean treefall and wind directions. Mean crown asymmetry (ratio of long and short diameters) was 1.26, and there were no significant differences in asymmetry values when current gap border trees and non border trees were compared. While trees may fall downhill and downwind, the high variation in treefall and wind directions precluded establishing a consistent statistical relationship between these data sets. I suggest that crown asymmetry, resulting from differential crown growth of trees on sloped-hillsides and within canopy gaps, exerts a strong additional influence on direction of fall.

Page Thumbnails

  • Thumbnail: Page 
391
    391
  • Thumbnail: Page 
392
    392
  • Thumbnail: Page 
393
    393
  • Thumbnail: Page 
394
    394
  • Thumbnail: Page 
395
    395
  • Thumbnail: Page 
396
    396
  • Thumbnail: Page 
397
    397
  • Thumbnail: Page 
398
    398
  • Thumbnail: Page 
399
    399
  • Thumbnail: Page 
400
    400