The anatomies of 44 galls are discussed with special attention given to the development, longevity, and tannin content of the nutritive tissues. Within the main section of the thesis, representative galls from the major cecidogenetic groups, with the exception of bacterial and Australian scale
galls, are studied. These include galls...
Hand-defoliation was evaluated for its ability to
simulate herbivory by cinnabar moth larvae, Tyria
jacobaeae (L.) (Arctiidae) on the weed tansy ragwort,
Senecio jacobaea L. (Asteraceae). The evaluation was done
on a field population of flowering ragwort, for three
different timings (early, middle, and late season) of
damage.
In the...
In this study an analysis of the commercial fishery of the Loreto Region, with emphasis on the fishery fleet of Iquitos, Amazon Basin, Peru, is presented. There is evidence of a progressive replacement of large species by smaller, more productive and lower value species in the landing of the commercial...
The cinnabar moth, Tyria jacobaeae (L.) (Lepidoptera:Arctiidae), was released in 1959 to control the grassland weed tansy ragwort, Senecio jacobaea L. (Asteraceae), despite evidence that caterpillars of this species can feed on native plants within the genera Senecio and Packera. Previous studies confirmed the moth's ability to develop on the...
Purple loosestrife is a wetland perennial that came to the eastern seaboard of
North America in ship ballast and raw wool in the 1800's. Since coming to the
United States, it has spread across the country, forming dense monospecific stands
in wetlands. Mechanical and chemical control was expensive and ineffective,...
In the first part of this study we monitored the development of biological control
of purple loosestrife Lythrum salicaria over a six-year period at Morgan Lake in western
Oregon. In 1992, two beetles, Galerucella pusilla and G. calmariensis (Coleoptera:
Chrysomelidae), were released to control the wetland weed at this test...
The cinnabar moth (Tyria jacobaeae (L.), Lepidoptera: Arctiidae) is an icon in
population ecology and biological control that has recently lost its shine based on evidence
that (1) it is less effective than alternatives (such as the ragwort flea beetle Longitarsus
jacobaeae (Waterhouse) (Coleoptera: Chrysomelidae) for controlling ragwort Senecio
jacobaea...
A study consisting of three parts was undertaken to investigate how variation in species interactions, population genetic structure, epidemiological parameters, and plant breeding system may influence the ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae). Interactions between natural enemy species may modify their net effect on...
To assess the effect of summer moisture stress on the capacity of tansy ragwort (Senecio jacobaea L.) to compensate for defoliation by the cinnabar moth (Tyria jacobaeae LT7), the performance of plants grown under different irrigation regimes was measured. The proportion of plants producing
new leaves following defoliation, the number...
Classic biological control can be a powerful option for those tasked with managing biological invasions; however, some biocontrol releases lead to non-target attack – feeding, damage or development on species other than the target species. The cinnabar moth, Tyria jacobaeae L. (Lepidoptera: Erebidae) was introduced to Western Oregon as a...