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.

Zur Kenntnis der Fichten-Blattwespen. IV. Die Dispersion

B. Ohnesorge and W. Thalenhorst
Zeitschrift für Pflanzenkrankheiten (Pflanzenpathologie) und Pflanzenschutz
Vol. 63, No. 4 (April 1956), pp. 197-211
Published by: Verlag Eugen Ulmer KG
Stable URL: http://www.jstor.org/stable/43231142
Page Count: 15
  • 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.
Zur Kenntnis der Fichten-Blattwespen. IV. Die Dispersion
Preview not available

Abstract

The „dispersion" (= distribution within the biotope) of Spruce Sawflies is determined, on the one side, by the ecological demands and oviposition habits of the adults and, on the other side, by the ecological differentiation of the biotope. The distribution pattern drawn by oviposition scarcely changes during the larval development and is still reflected in the cocoon layer. Dispersion is discontinuous when population density is extremely low or when specific behaviour confines oviposition to trees showing, in due time, the suitable phase of bud opening (Pristiphora abietina, Pachynematus pallescens). In the other cases, dispersion is more or less continuous according to the climatic differentiation of the biotope.

Page Thumbnails

  • Thumbnail: Page 
197
    197
  • Thumbnail: Page 
198
    198
  • Thumbnail: Page 
199
    199
  • Thumbnail: Page 
200
    200
  • Thumbnail: Page 
201
    201
  • Thumbnail: Page 
202
    202
  • Thumbnail: Page 
203
    203
  • Thumbnail: Page 
204
    204
  • Thumbnail: Page 
205
    205
  • Thumbnail: Page 
206
    206
  • Thumbnail: Page 
207
    207
  • Thumbnail: Page 
208
    208
  • Thumbnail: Page 
209
    209
  • Thumbnail: Page 
210
    210
  • Thumbnail: Page 
211
    211