Newer, selective insecticides with few negative impacts on natural enemies and competitor species are needed for effective, sustainable management of the western flower thrips, Frankliniella occidentalis (Pergande). The purpose of this study was to evaluate the impacts on natural enemies and competitor thrips species of insecticides used for control of...
The quality of lumber and veneer recovered from logs of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is directly influenced by the maximum limb size attained on the crop tree. Because limb sizes are influenced by standdensity regimes, a need has arisen for quantitative tools that link a wide array of silvicultural...
Liriomyza huidobrensis (Blanchard) is a highly destructive invasive leafminer pest
currently causing extensive damage to vegetable and horticultural crops around the world. Liriomyza
langei Frick is a leafminer pest native to California that cannot currently be morphologically distinguished
from L. huidobrensis. We used a DNA-barcoding approach, a published PCR-RFLP method,...
BACKGROUND: The spread of the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), resulted in the worldwide destabilization of established integrated pest management programs for many crops. Efforts to control the pest and the thrips-vectored tospoviruses with calendar applications of broad-spectrum insecticides have been unsuccessful. The result has been a...
Recent comparative studies across sex-changing animals have found that the relative size and age at sex change are strikingly invariant. In particular, 91%–97% of the variation in size at sex change across species can be explained by the simple rule that individuals change sex when they reach 72% of their...
A NE–SW-trending graben at Kap Dalton on the Blosseville Kyst contains an at least 600 m thick
succession of Eocene basalt lavas and sediments. The succession has been investigated by new field
work, geochemical analysis and radiometric dating by the ⁴⁰Ar-³⁹Ar incremental heating method.
The results show that the volcanic...
As in various freshwater and coastal marine ecosystems worldwide, seasonal bottom water hypoxia is a recurring phenomenon in Lake Erie's central basin. While bottom hypoxia can strongly affect sessile benthic animals, its effects on mobile organisms such as fish are less understood. We evaluated the potential for bottom hypoxia to...
Alien grass invasions in arid and semi-arid ecosystems are resulting in grass–fire cycles and ecosystem-level transformations that severely diminish ecosystem services. Our capacity to address the rapid and complex changes occurring in these ecosystems can be enhanced by developing an understanding of the environmental factors and ecosystem attributes that determine...
To evaluate the impact of hypoxia (< 2 mg O₂ l⁻¹) on habitat quality of pelagic prey fishes in the northern Gulf of Mexico, we used a spatially explicit, bioenergetics-based growth rate potential (GRP) model to develop indices of habitat quality. Our focus was on the pelagic bay anchovy Anchoa...
Prescribed fire is commonly applied world-wide as a tool for enhancing habitats and altering resource-selection patterns of grazing animals. A scientific basis for this practice has been established in some ecosystems but its efficacy has not been rigorously evaluated on mesic sagebrush steppe. Beginning in 2003, resource-selection patterns of beef...