From 2009 to 2012, 16 species of Curculionidae (Coleoptera) from the subfamily Lixinae Schoenherr... more From 2009 to 2012, 16 species of Curculionidae (Coleoptera) from the subfamily Lixinae Schoenherr were collected on 17 species of food plants in Iranian rangelands. Identified species belong to seven genera in the tribes Lixini and Cleonini. The host plants from which they were collected were in the families Asteraceae, Fabaceae, Apiaceae, Campanulaceae, Brassicaceae and Zygophyllaceae. Of the 16 species that we captured, two (Lixus subfarinosus Desbrochers, 1893 and Larinus remissus Faust, 1889) represent the first records from Iran. These new data also extend the known ranges of several species (Larinus fucatus Faust, 1894, Larinus grisescens Gyllenhal, 1835, Microlarinus rhinocylloides Hochhuth, 1847 and Bangasternus planifrons (Brulle, 1832) in Iran. The distribution of beetles and their associated host plants are presented and ecological notes on each species are provided.
The balsam woolly adelgid (Adelges piceaeRatzeburg) attacks subalpine fir (Abies lasiocarpa(Hook.... more The balsam woolly adelgid (Adelges piceaeRatzeburg) attacks subalpine fir (Abies lasiocarpa(Hook.) Nutt.) in eastern Washington, Oregon, and northern Idaho. Historical balsam woolly adelgid distributions present an opportunity to understand climatic factors that influence the species’ distribution at a landscape scale. The distribution data allows for creation of predictive models that detail the likelihood of occurrence and associated geographic data allow modeling of species dispersal. Predictive variables linked to the distribution of the hosts and to abiotic environmental conditions were utilized to create a spatial probability model of occurrence. Balsam woolly adelgid predominantly disperses by wind, and hence, both wind speed and wind direction were used to create a dispersal probability model. Results from wind dispersal modeling suggested that two-thirds of the new infestations were due to July and August wind direction and speed. Average July winds ranged from 0.5 to 3.27 ...
The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched t... more The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched to mobilize biodiversity data from 3 million specimens of butterflies and moths in United States natural history collections (http://www.lep-net.org/). LepNet was initially conceived as a North American effort but the project seeks collaborations with museums and other organizations worldwide. The overall goal is to transform Lepidoptera specimen data into readily available digital formats to foster global research in taxonomy, ecology and evolutionary biology.
The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched t... more The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched to mobilize biodiversity data from 3 million specimens of butterflies and moths in United States natural history collections (http://www.lep-net.org/). LepNet was initially conceived as a North American effort but the project seeks collaborations with museums and other organizations worldwide. The overall goal is to transform Lepidoptera specimen data into readily available digital formats to foster global research in taxonomy, ecology and evolutionary biology.
The use of biochar as a soil amendment in forest ecosystems can be beneficial in the restoration ... more The use of biochar as a soil amendment in forest ecosystems can be beneficial in the restoration of degraded soils. Forest insects such as the Douglas-fir tussock moth, Orgyia pseudotsugata (McDonnough) (Lepidoptera: Erebidae), may be exposed to biochar when the material is applied. Two experiments were conducted using biochar either (1) applied to the surface of the diet at three rates (0, 5, and 10 mg) or (2) incorporated into synthetic diet at four rates (0, 10, 20, and 40% volume/volume). The objective of both experiments was to determine if biochar on the surface or incorporated into a synthetic diet affected development and survival of O. pseudotsugata larvae. In both experiments, there was a significant decrease in estimated time to larval mortality in all biochar treatments compared to untreated controls. In the surface-applied biochar experiment, there was a significant difference in larval weight gain at day 12 between the control and 10 mg biochar treatments. In the exper...
Seed orchards produce high-quality seed from selected tree genotypes. In the intermountain west, ... more Seed orchards produce high-quality seed from selected tree genotypes. In the intermountain west, Conophthorus ponderosae Hopkins (Coleoptera: Scolytidae) is a pest in seed orchards of ponderosa pine, Pinus ponderosa (Laws). The effect of myrcene as a deterrent to coneattack by C. ponderosae in a ponderosa pine seed orchard was examined. Two factors were considered, timing of cone cluster attack and average brood production per cone cluster. There was a delayed attack by C. ponderosae on cones treated with vials of myrcene attached at thebase of cone clusters. During both 2003 and 2004, final brood production per cone was not affected significantly by the presence of myrcene. During 2003, brood production was influenced by the timing of attack, with later attacks resulting in fewer brood adults per cone cluster. The toxicity of myrcene to adult C. ponderosae was examined in a laboratory and compared with that of (+)-α-pinene, another host-produced monoterpene that acts as a synergist...
Under laboratory conditions, Dendroctonus frontalis Zimmermann and Ips grandicollis (Eichhoff) ad... more Under laboratory conditions, Dendroctonus frontalis Zimmermann and Ips grandicollis (Eichhoff) adults became self-marked with fluorescent powders upon emergence from treated logs. The technique provided a reliable procedure for marking adult bark beetles without having to handle them. When the powder remained dry, nearly all of the emerged beetles were marked. However, the percentage of marked beetles decreased dramatically following simulated rain events. Once marked, the mark remains intact on beetles stored dry or in ethylene glycol or ethanol (95%). Marking did decrease the adult life span of both D. frontalis and I. grandicollis, but had no significant effect on flight initiation by either species or semiochemical perception by I. grandicollis. No semiochemical tests were conducted with D. frontalis. If beetles are recaptured shortly following emergence and self-marking, the technique should be useful for examining scolytid dispersal in the field.
Balsam woolly adelgid is an invasive pest of firs in the United States. Aerial surveys are conduc... more Balsam woolly adelgid is an invasive pest of firs in the United States. Aerial surveys are conducted for detection of adelgid infestations but other remotely sensed data may also be useful. Our objective was to determine if high spectral resolution, branch-level data can be used to distinguish infested from noninfested trees. Stepwise discriminant analysis yielded a three-variable model (the red-green index and two narrow-bands (one at 670 nm and the other at 1912 nm)) that classified infested versus non-infested trees with 94% accuracy compared with the 83% accuracy obtained with a single-variable model. The response of trees in narrow spectral bands was integrated across wavebands to simulate measurements from the multispectral SPOT5-HRVIR sensor. Stepwise discriminant analysis again yielded a three-variable model (simple ratio, the SPOT5-HRVIR band in the SWIR region and NDVI) with similar accuracy (93%) at discriminating infested from non-infested trees compared with the 83% acc...
From 2009 to 2012, 16 species of Curculionidae (Coleoptera) from the subfamily Lixinae Schoenherr... more From 2009 to 2012, 16 species of Curculionidae (Coleoptera) from the subfamily Lixinae Schoenherr were collected on 17 species of food plants in Iranian rangelands. Identified species belong to seven genera in the tribes Lixini and Cleonini. The host plants from which they were collected were in the families Asteraceae, Fabaceae, Apiaceae, Campanulaceae, Brassicaceae and Zygophyllaceae. Of the 16 species that we captured, two (Lixus subfarinosus Desbrochers, 1893 and Larinus remissus Faust, 1889) represent the first records from Iran. These new data also extend the known ranges of several species (Larinus fucatus Faust, 1894, Larinus grisescens Gyllenhal, 1835, Microlarinus rhinocylloides Hochhuth, 1847 and Bangasternus planifrons (Brulle, 1832) in Iran. The distribution of beetles and their associated host plants are presented and ecological notes on each species are provided.
The balsam woolly adelgid (Adelges piceaeRatzeburg) attacks subalpine fir (Abies lasiocarpa(Hook.... more The balsam woolly adelgid (Adelges piceaeRatzeburg) attacks subalpine fir (Abies lasiocarpa(Hook.) Nutt.) in eastern Washington, Oregon, and northern Idaho. Historical balsam woolly adelgid distributions present an opportunity to understand climatic factors that influence the species’ distribution at a landscape scale. The distribution data allows for creation of predictive models that detail the likelihood of occurrence and associated geographic data allow modeling of species dispersal. Predictive variables linked to the distribution of the hosts and to abiotic environmental conditions were utilized to create a spatial probability model of occurrence. Balsam woolly adelgid predominantly disperses by wind, and hence, both wind speed and wind direction were used to create a dispersal probability model. Results from wind dispersal modeling suggested that two-thirds of the new infestations were due to July and August wind direction and speed. Average July winds ranged from 0.5 to 3.27 ...
The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched t... more The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched to mobilize biodiversity data from 3 million specimens of butterflies and moths in United States natural history collections (http://www.lep-net.org/). LepNet was initially conceived as a North American effort but the project seeks collaborations with museums and other organizations worldwide. The overall goal is to transform Lepidoptera specimen data into readily available digital formats to foster global research in taxonomy, ecology and evolutionary biology.
The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched t... more The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched to mobilize biodiversity data from 3 million specimens of butterflies and moths in United States natural history collections (http://www.lep-net.org/). LepNet was initially conceived as a North American effort but the project seeks collaborations with museums and other organizations worldwide. The overall goal is to transform Lepidoptera specimen data into readily available digital formats to foster global research in taxonomy, ecology and evolutionary biology.
The use of biochar as a soil amendment in forest ecosystems can be beneficial in the restoration ... more The use of biochar as a soil amendment in forest ecosystems can be beneficial in the restoration of degraded soils. Forest insects such as the Douglas-fir tussock moth, Orgyia pseudotsugata (McDonnough) (Lepidoptera: Erebidae), may be exposed to biochar when the material is applied. Two experiments were conducted using biochar either (1) applied to the surface of the diet at three rates (0, 5, and 10 mg) or (2) incorporated into synthetic diet at four rates (0, 10, 20, and 40% volume/volume). The objective of both experiments was to determine if biochar on the surface or incorporated into a synthetic diet affected development and survival of O. pseudotsugata larvae. In both experiments, there was a significant decrease in estimated time to larval mortality in all biochar treatments compared to untreated controls. In the surface-applied biochar experiment, there was a significant difference in larval weight gain at day 12 between the control and 10 mg biochar treatments. In the exper...
Seed orchards produce high-quality seed from selected tree genotypes. In the intermountain west, ... more Seed orchards produce high-quality seed from selected tree genotypes. In the intermountain west, Conophthorus ponderosae Hopkins (Coleoptera: Scolytidae) is a pest in seed orchards of ponderosa pine, Pinus ponderosa (Laws). The effect of myrcene as a deterrent to coneattack by C. ponderosae in a ponderosa pine seed orchard was examined. Two factors were considered, timing of cone cluster attack and average brood production per cone cluster. There was a delayed attack by C. ponderosae on cones treated with vials of myrcene attached at thebase of cone clusters. During both 2003 and 2004, final brood production per cone was not affected significantly by the presence of myrcene. During 2003, brood production was influenced by the timing of attack, with later attacks resulting in fewer brood adults per cone cluster. The toxicity of myrcene to adult C. ponderosae was examined in a laboratory and compared with that of (+)-α-pinene, another host-produced monoterpene that acts as a synergist...
Under laboratory conditions, Dendroctonus frontalis Zimmermann and Ips grandicollis (Eichhoff) ad... more Under laboratory conditions, Dendroctonus frontalis Zimmermann and Ips grandicollis (Eichhoff) adults became self-marked with fluorescent powders upon emergence from treated logs. The technique provided a reliable procedure for marking adult bark beetles without having to handle them. When the powder remained dry, nearly all of the emerged beetles were marked. However, the percentage of marked beetles decreased dramatically following simulated rain events. Once marked, the mark remains intact on beetles stored dry or in ethylene glycol or ethanol (95%). Marking did decrease the adult life span of both D. frontalis and I. grandicollis, but had no significant effect on flight initiation by either species or semiochemical perception by I. grandicollis. No semiochemical tests were conducted with D. frontalis. If beetles are recaptured shortly following emergence and self-marking, the technique should be useful for examining scolytid dispersal in the field.
Balsam woolly adelgid is an invasive pest of firs in the United States. Aerial surveys are conduc... more Balsam woolly adelgid is an invasive pest of firs in the United States. Aerial surveys are conducted for detection of adelgid infestations but other remotely sensed data may also be useful. Our objective was to determine if high spectral resolution, branch-level data can be used to distinguish infested from noninfested trees. Stepwise discriminant analysis yielded a three-variable model (the red-green index and two narrow-bands (one at 670 nm and the other at 1912 nm)) that classified infested versus non-infested trees with 94% accuracy compared with the 83% accuracy obtained with a single-variable model. The response of trees in narrow spectral bands was integrated across wavebands to simulate measurements from the multispectral SPOT5-HRVIR sensor. Stepwise discriminant analysis again yielded a three-variable model (simple ratio, the SPOT5-HRVIR band in the SWIR region and NDVI) with similar accuracy (93%) at discriminating infested from non-infested trees compared with the 83% acc...
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