Size-Dependent Root Herbivory on Cynoglossum officinale

Abstract

The weevil Ceuthorhynchus (Boraginobius) cruciger was the most important root herbivore of the biennial herb Cynoglossum officinale in Meijendel, The Netherlands. Only a few other species were found, but always in less than 5% of the plants. The infestation level of flowering plants of C. officinale was 22% in 1988, 56% in 1989 and 61% in 1990; in rosettes 0% in 1988 and 6% in 1989. Weevil attack was size-dependent: weevils preferred large plants over small plants and, when controlling for size, flowering plants over rosettes