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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
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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.
Zeitschrift für Pflanzenkrankheiten (Pflanzenpathologie) und Pflanzenschutz © 1956 Verlag Eugen Ulmer KG