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.

The Role of Lemming Herbivory in the Sex Ratio and Shoot Demography of Willow Populations

Martin Predavec and Kjell Danell
Oikos
Vol. 92, No. 3 (Mar., 2001), pp. 459-466
Published by: Wiley on behalf of Nordic Society Oikos
Stable URL: http://www.jstor.org/stable/3547163
Page Count: 8
  • Read Online (Free)
  • 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.
The Role of Lemming Herbivory in the Sex Ratio and Shoot Demography of Willow Populations
Preview not available

Abstract

We investigated the role of lemming herbivory on the age structure and physical form of a stand of willows (Salix lanata) using lemming scars on stems as an indication of past herbivory. Salix lanata had a female-biased sex ratio comparable to that found in other willow species and it has been proposed that such a sex ratio may be due to selective herbivory on male genets. There was, however, no difference in the degree of scarring in male and female plants. Scarring did not appear to change the overall physical structure of the willows including the number of stems, the proportion of dead steams and the degree of branching. However, 72% of scarred 7 mm stems were dead, compared to only 22% of non-scarred stems, suggesting that lemming herbivory may play a role in ramet death. There was a significant positive correlation between stem ages and the lemming cycle as determined by the frequency of scars. With experimental scarring, S. lanata increased its production of new shoots in relation to the degree of scarring. We suggest that this demonstrates a pattern of compensatory growth in willows, whereby they take advantage of a period of relatively low herbivory following the crash of the lemming populations in order to compensate for damage that occurred during the lemming peak.

Page Thumbnails

  • Thumbnail: Page 
459
    459
  • Thumbnail: Page 
460
    460
  • Thumbnail: Page 
461
    461
  • Thumbnail: Page 
462
    462
  • Thumbnail: Page 
463
    463
  • Thumbnail: Page 
464
    464
  • Thumbnail: Page 
465
    465
  • Thumbnail: Page 
466
    466