A vigor-structured model for mountain pine beetle outbreak dynamics within a forest stand is proposed and analyzed. This model explicitly tracks the changing vigor structure in the stand. All model parameters, other than beetle vigor preference, were determined by fitting model components to empirical data. An abrupt threshold for tree mortality to beetle densities allows for model simplificati...

Biological control agents may have unintended effects on native biota, particularly species that are closely related to the target invader. Here, we explored how Chrysolina quadrigemina, a beetle introduced to control the invasive weed Hypericum perforatum, impacts native H. punctatum in Tompkins County, New York, USA. Using a suite of complementary field surveys and experimental manipulations,...

rove beetle dermatitis produced by the family staphylinidae genus paederus has world- wide distribution some one hundred species of paederus have been found, but it is believed that only 30 of these produce dermatitis. up to 1976 three species of paederus have been found in iran as: p. fusciped curtis; p. pietschmanni bershaner , and p. spectabilis kraatz . observations on the biology of paeder...

the seed beetle, stafor limbatus (horn) (col.: bruchidae), collected from bushehr and yazd provinces, iran, on acasia sp. and prosopis farcta, is newly recorded from iran. it is native to southwestern united states but distributed in various parts of the world. the beetle was identified by delobel from france.

Larval and adult life stages are described for Contortylenchus brevicomi (Massey) Rühm parasitizing a Mississippi population of Dendroctonus frontalis, the southern pine beetle. Fourth-stage larvae and free-living adult females of this species are identified and described for the first time. The life cycle of C. brevicomi can be reconstructed from this study. The adult female nematode lays eggs...

the cowpea seed beetle, callosobruchus maculatus (fab.) (coleoptera: chrysomelidae: bruchinae) is one of the major pests infesting stored pulses and is distributed worldwide. in this research, efficiency of plant extracts from eucalyptus globulus labill. and eucalyptus camaldulensis dehnh. were tested against the cowpea seed beetle for its antifeedant activity. several experiments were designed...