Browsing by Author "Arneson, Alicia"

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    The Distribution, Seasonal Abundance, and Environmental Factors Contributing to the Presence of the Asian Longhorned Tick (Haemaphysalis longicornis, Acari: Ixodidae) in Central Appalachian Virginia
    Cumbie, Alexandra N.; Whitlow, Amanda M.; Arneson, Alicia; Du, Zhiyuan; Eastwood, Gillian (Oxford University Press, 2022-05-30)
    Over the past decade, Haemaphysalis longicornis, the Asian longhorned tick, has undergone a geographic range expansion in the United States, from its historical range in east Asia. This tick has been characterized by its frequent parasitism of livestock, an ability to reproduce through parthenogenesis, and its ability to transmit a variety of vector-borne pathogens to livestock, wildlife, and human hosts in its native geographic range. Thus far in the United States, 17 states have reported H. longicornis populations, including 38 counties in Virginia. These numbers come from presence-absence reports provided to the U.S. Department of Agriculture, but little has been reported about this ticks' seasonality in Virginia or its habitat preferences. Our current study detected H. longicornis populations in seven of the nine surveyed counties in Virginia. Haemaphysalis longicornis were observed in multiple habitat types including mixed hardwood forests and pastures, with abundant H. longicornis populations detected at one particular pasture site in Wythe County. This study also attempted to investigate environmental conditions that may be of importance in predicting tick presence likelihood. While sample size limited the scope of these efforts, habitat type and climatic metrics were found to be important indicators of H. longicornis collection success and abundance for both the nymphal and larval life stages. This current study reports useful surveillance data for monitoring these tick populations as they become established in the western half of Virginia and provides insight into their current distribution and maintenance over a large study region.
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    The Impact of Predation of Laricobius nigrinus (Coleoptera: Derodontidae) on Adelges tsugae (Hemiptera: Adelgidae) and Tsuga canadensis (Pinales: Pinaceae) Tree Health
    Preston, Carrie E.; Arneson, Alicia; Seiler, John R.; Salom, Scott M. (MDPI, 2023-03-29)
    The hemlock woolly adelgid (HWA), Adelges tsugae, has threatened the sustainable management of Tsuga canadensis in the eastern United States. Biological control efforts have led to the establishment of Laricobius nigrinus, a specialist predator of HWA. Although L. nigrinus has a significant impact on HWA populations, its effect on the health of HWA’s host is unknown. In 2020, 14 eastern hemlocks at one site in Virginia were selected to determine whether predation of L. nigrinus at different densities on HWA populations had an effect on tree health. Laricobius nigrinus predation significantly impacted the HWA sistens generation, resulting in significantly more new shoots produced on treatment branches with the greatest density of L. nigrinus adults. Final HWA density was lowest on treatment branches with L. nigrinus, followed by the negative control, and the treatment without L. nigrinus. In June, the photosynthetic rate was significantly greater for the negative control, followed by L. nigrinus treatments. There were no statistical differences among measured tree physiological parameters in July and October, indicating a temporary effect from L. nigrinus predation on hemlock tree physiology.