Publications by authors named "Richard Cowles"

Boxwood blight causes great losses to the boxwood nursery industry and landscapes in 30 states in the United States. Understanding the epidemiological factors governing disease development will be important for disease forecasting and design of best management practices. We evaluated the effect of leaf wetness period (lwp) and temperature on lesion development and sporulation on three boxwood cultivars under controlled conditions to develop predictive models for disease development.

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In this study, we describe the legacy effects of a soil sulfur amendment experiment performed 6 years prior and the resulting alterations to the rhizosphere communities of fir trees on a Christmas tree plantation. The pH of bulk soil was ∼1.4 pH units lower than that of untreated soils and was associated with reduced Ca, Mg, and organic matter contents.

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A number of fir species () are produced as Christmas trees around the world. In particular, Fraser fir ( (Pursh) Poir.) is popular as it yields high-quality Christmas trees in temperate North America and Europe.

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Worldwide studies have used the technique of pollen trapping, collecting pollen loads from returning honey bee (Apis mellifera L.) (Hymenoptera: Apidae) foragers, to evaluate the exposure of honey bees to pesticides through pollen and as a biomonitoring tool. Typically, these surveys have found frequent contamination of pollen with multiple pesticides, with most of the estimated risk of acute oral toxicity to honey bees coming from insecticides.

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The addition of sucrose to insecticides targeting spotted wing drosophila, Drosophila suzukii (Matsumura), enhanced lethality in laboratory, semifield, and field tests. In the laboratory, 0.1% sucrose added to a spray solution enhanced spotted wing drosophila feeding.

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Competitive enzyme-linked immunosorbent assay was used to quantify the amounts of the neonicotinoids clothianidin and imidacloprid in Poa annua L. clippings from treated golf course fairways. Average clothianidin residues 7 d after application ranged from 674 to 1,550 ng/g tissue in 2012 and 455-2,220 ng/g tissue in 2013.

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Use of early ripening highbush blueberry cultivars to avoid infestation and mass trapping were evaluated for managing spotted wing drosophila, Drosophila suzukii (Matsumura). Fourteen highbush blueberry cultivars were sampled for spotted wing drosophila infestation. Most 'Earliblue', 'Bluetta', and 'Collins' fruit were harvested before spotted wing drosophila oviposition commenced, and so escaped injury.

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We determined the attractiveness of a new chemical lure compared with fermented food baits in use for trapping Drosophila suzukii Matsumura, spotted wing drosophila (Diptera: Drosophilidae), in Connecticut, New York, and Washington in the United States and at Dossenheim in Germany. The chemical lure (SWD lure) and food baits were compared in two types of traps: the dome trap and a cup trap. Regardless of trap type, numbers of male and female D.

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Relative increases of bed bug, Cimex lectularius L., populations are probably due in large measure to their resistance to pyrethroids, which have been used extensively against urban pests. A Connecticut population of bed bugs was assessed for sensitivity to pyrethroids and exposed to commonly-used commercial insecticides applied to various substrates on which the residues were allowed to age for 0-24 wk.

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The armored scales Fiorinia externa Ferris and Aspidiotus cryptomeriae Kuwana (Hemiptera: Diaspididae) are increasingly damaging to Christmas tree plantings in southern New England. The systemic insecticide dinotefuran was investigated for selectively suppressing armored scale populations relative to their natural enemies in cooperating growers' fields in 2008 and 2009. Banded soil application of dinotefuran resulted in poor control.

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In 2009, pyrethroid resistance was confirmed for seven "annual bluegrass weevil" Listronotus maculicollis Kirby (Coleoptera: Curculionidae) adult populations from southern New England. The mechanisms responsible for conferring this resistance were unknown. In this study, topical application bioassays with bifenthrin and bifenthrin combined with synergists affecting three detoxification systems were conducted on four field-collected adult populations of L.

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Topical application bioassays of bifenthrin and lambda-cyhalothrin were conducted on field-collected populations of Listronotus maculicollis Kirby (Coleoptera: Curculionidae) from eight southern New England golf courses, six in Connecticut, one in Massachusetts, and one in Rhode Island. Concentrations versus mortality regression lines were estimated to compare the LD50 values and resistance ratios for each insecticide and each population. The LD50 ranges for bifenthrin and lambda-cyhalothrin were 1.

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A sporodochial fungus collected from the elongate hemlock scale, Fiorinia externa (Ferris) in Coventry, Connecticut, is described. This fungus has characteristics of both Metarhizium and Myrothecium but develops setae surrounding white to buff sporodochia and dry conidia in chains, a combination of characters found in neither genus. Phylogenetic analyses of the complete small subunit ribosomal DNA (ssu), partial ef1-alpha, and complete 5.

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The sex pheromone of the scarab beetle, Phyllophaga anxia, is a blend of the methyl esters of two amino acids, L-valine and L-isoleucine. A field trapping study was conducted, deploying different blends of the two compounds at 59 locations in the United States and Canada. More than 57,000 males of 61 Phyllophaga species (Coleoptera: Scarabaeidae: Melolonthinae) were captured and identified.

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