Detection of Adelges tsugae (Hemiptera: Adelgidae) wool using Velcro-covered balls

2021 ◽  
pp. 1-11
Author(s):  
Jeffrey G. Fidgen ◽  
Mark C. Whitmore ◽  
Chris J.K. MacQuarrie ◽  
Jean J. Turgeon
Keyword(s):  
Life Cycle ◽  
North America ◽  
Insect Pest ◽  
Adelges Tsugae ◽  
Eastern North America ◽  
Sample Sizes ◽  
Field Sampling ◽  
Individual Tree ◽  
Precision Level ◽  
The Relationship

Abstract Adelges tsugae Annand (Hemiptera: Adelgidae), a nonindigenous insect pest of hemlock (Tsuga spp.) (Pinaceae) in eastern North America, spends most of its life cycle within an ovisac, which resembles a woolly white mass on twigs. We evaluated the probability of detecting adelgid wool with Velcro®-covered balls when taking an increasing number of samples per tree (field sampling) and number of trees per simulated stand. We examined the relationship between the detection of adelgid wool using this technique and the incidence of A. tsugae-infested twigs by sampling lower-crown branch tips of the same trees. We found that the probability of detecting wool with ball sampling increased with number of ball samples per tree, with number of trees per simulated stand, and with increasing incidence of ovisacs in the lower crown. When sampling an individual tree, we found that 20 ball samples per tree achieved a targeted precision level of 0.75, but when sampling a stand, we found that 10 ball samples per tree took the least time for the range of simulated A. tsugae infestations we tested. These sample sizes are recommended for detection of A. tsugae infestations on an individual tree and in a hemlock stand.

scholarly journals Rain, Riches, and Empire: The Relationship between Nations Ruling Distant Lands, Nations of Great Wealth, and Regions of Regular Moderate Atmospheric Precipitation

2017 ◽  
Vol 9 (3) ◽  
pp. 455-469 ◽  
Author(s):  
L. Bruce Railsback
Keyword(s):  
North America ◽  
Small Proportion ◽  
Average Rate ◽  
Atmospheric Precipitation ◽  
Eastern North America ◽  
Human History ◽  
Per Capita Gdp ◽  
Per Capita ◽  
Human Construction ◽  
The Relationship

Abstract Two of the great questions of human history and economics are why some nations held far-flung empires and why some presently enjoy great wealth. One factor that should be included in the inevitably multifactorial answer to these questions is regular moderate precipitation (precipitation with an average rate between 30 and 120 mm for each month). Only a small proportion of Earth’s surface has regular moderate precipitation, and most of that area is in Europe and eastern North America. Strikingly, of the 13 nations that held geographically discontinuous multicontinental transoceanic empires, 12 overlap with regions of regular moderate precipitation. Similarly, of the 20 nations with the greatest per capita GDP in 2015, 16 coincide with regions of regular moderate precipitation. These relationships are presumably rooted in the greater success, or lesser inhibition, of human construction of infrastructure, husbandry of livestock, and cultivation of crops, some combination of which likely allowed industrialization, projection of geopolitical power, and accumulation of wealth. One instructive example is that of China, which has a climate superficially like that of Europe and eastern North America but no regions of regular moderate rainfall, and which neither developed an overseas empire nor is among the world’s nations with greatest per capita GDP. Furthermore, concentration of nations holding empires and wealth in the Northern Hemisphere and their absence from the south can be linked to the coincidence that the Southern Hemisphere’s latitudinal zone of regular moderate rainfall is over the Southern Ocean, where there is little land on which human societies could have enjoyed the benefits of that supportive climate.

scholarly journals Temporal Asynchrony of Adult Emergence Between Leucopis argenticollis and Leucopis piniperda (Diptera: Chamaemyiidae), Predators of the Hemlock Woolly Adelgid (Hemiptera: Adelgidae), with Implications for Biological Control

2020 ◽  
Vol 49 (4) ◽  
pp. 823-828
Author(s):  
Alex N Neidermeier ◽  
Darrell W Ross ◽  
Nathan P Havill ◽  
Kimberly F Wallin
Keyword(s):  
Biological Control ◽  
North America ◽  
Pacific Northwest ◽  
Adult Emergence ◽  
Hemlock Woolly Adelgid ◽  
Adelges Tsugae ◽  
Tsuga Heterophylla ◽  
Eastern North America ◽  
Biological Control Agents ◽  
The Pacific

Abstract Two species of silver fly, Leucopis argenticollis (Zetterstedt) and Leucopis piniperda (Malloch) (Diptera: Chamaemyiidae), from the Pacific Northwest region of North America have been identified as potential biological control agents of hemlock woolly adelgid (Hemiptera: Adelgidae: Adelges tsugae Annand) in eastern North America. The two predators are collectively synchronized with A. tsugae development. To determine whether adult emergence of the two species of silver fly are also synchronized with one another, we collected adult Leucopis which emerged from A. tsugae-infested western hemlock [Pinaceae: Tsuga heterophylla (Raf.) Sarg.] from four sites in the Pacific Northwest over a 29-d period. Specimens were collected twice daily in the laboratory and identified to species using DNA barcoding. The study found that more adult Leucopis were collected in the evening than the morning. Additionally, the daily emergences of adults over the 29-d sampling period exhibited sinusoidal-like fluctuations of peak abundance of each species, lending evidence to a pattern of temporal partitioning. This pattern could have logistical implications for their use as biological control agents in eastern North America, namely the need to release both species for maximum efficacy in decreasing A. tsugae populations.

Taxonomy of the Carex straminea complex (Cyperaceae)

1997 ◽  
Vol 75 (12) ◽  
pp. 2177-2195 ◽  
Author(s):  
P. E. Rothrock ◽  
A. A. Reznicek ◽  
L. R. Ganion
Keyword(s):  
Numerical Analysis ◽  
North America ◽  
Key Words ◽  
Endemic Species ◽  
Atlantic Coast ◽  
Interspecific Variation ◽  
Eastern North America ◽  
Upper Midwest ◽  
The Relationship ◽  
Sem Investigation

The Carex straminea complex (section Ovales) consists of five species limited to hydric communities of eastern North America. Based upon gross morphology and perigynium structure, these species are closely aligned with the Carex albolutescens complex but not the western species Carex feta. An SEM investigation of the micromorphology of achene and style epidermis from 15 species of Carex section Ovales demonstrated much interspecific variation. As a result, these data could not confirm the relationship between the C. straminea complex and the C. albolutescens complex but did support the delimitation of section Ovales. Numerical analysis showed that characters of the inflorescence and perigynium are satisfactory for separating C. straminea from Carex hormathodes, a species limited to the Atlantic coast. Likewise, characters of inflorescence, pistillate scale, and perigynium could clearly separate the geographically widespread Carex alata from the Florida endemic species Carex vexans. A fifth and relatively distinctive species, Carex suberecta, was found to have a narrow ecological preference for fens and a distribution limited to the upper Midwest, with outlying populations in western Virginia. Putative natural hybrids are documented between Carex scoparia and Carex longii and some species in the C. straminea complex. Key words: Carex, Cyperaceae, section Ovales, taxonomy, SEM, biogeography, hybrid.

Regional variation in the terminal Pleistocene and early Holocene radiocarbon record of eastern North America

2013 ◽  
Vol 79 (2) ◽  
pp. 175-188 ◽  
Author(s):  
D. Shane Miller ◽  
Joseph A.M. Gingerich
Keyword(s):  
North America ◽  
Regional Variation ◽  
Probability Distributions ◽  
Younger Dryas ◽  
Eastern North America ◽  
Northeastern United States ◽  
Radiocarbon Dates ◽  
Terminal Pleistocene ◽  
The Relationship ◽  
Data Result

AbstractIn this paper we use radiocarbon dates to evaluate the signature of the Younger Dryas Chronozone (YDC) in eastern North America. Using an approach that examines radiocarbon dates by region, we argue that the northeastern United States shows a better overall representation of radiocarbon dates when compared to the Mid-Atlantic and Southeast. These data result in a peak in summed probability distributions during the YDC, which is often interpreted as evidence of population growth. Further examination of these distributions, however, illustrates that differential standard deviations, varying sample size, and the effect of taphonomic and research biases likely overwhelm any demographic signatures in our study sample. Consequently, the frequency of radiocarbon dates by itself is insufficient for understanding the relationship between climate, culture and demography in eastern North America.

scholarly journals First Report of the Aecial State of Melampsora larici-populina on Larix spp. in North America

Plant Disease ◽  
2005 ◽  
Vol 89 (11) ◽  
pp. 1242-1242 ◽  
Author(s):  
J. Grondin ◽  
M. Bourassa ◽  
R. C. Hamelin
Keyword(s):  
Life Cycle ◽  
North America ◽  
Morphological Characteristics ◽  
Pcr Amplification ◽  
Eastern North America ◽  
Populus Balsamifera ◽  
Specific Primers ◽  
Complete Life Cycle ◽  
Pathogenic Variation ◽  
The Many

Melampsora larici-populina Kleb. was reported for the first time in eastern North America during 2002, on Populus spp., its telial host (1). M. larici-populina, a heteroecious rust, alternates between species of Populus and Larix. Since M. larici-populina was observed again in 2003, we investigated the possibility that its basidiospores may infect larch (Larix spp.) resulting in spermogonia and aecia. Identification of Melampsora species from aeciospore morphology is difficult but urediniospores are distinctive. This is important since the native M. medusae also alternates between Populus and Larix spp. During the spring of 2004, aecia were observed on needles of exotic (Larix decidua Mill. and L. leptolepis (Siebold and Zucc.) Gordon) and indigenous (L. laricina (K. Koch)) larch in an arboretum in Lotbinière (Quebec, Canada) where M. larici-populina has previously been found. Larch needles with yellow blister-like fructifications were collected in May 2004 and fixed on top of petri plates to allow aeciospore release onto leaves of Jackii poplar (Populus balsamifera L. × P. deltoides Marsh.). After approximately 10 days, uredinia appeared on the abaxial surface of the poplar leaves. Some of the many needles collected yielded uredinia cultures on Jackii poplars. The majority of these cultures were identified as being M. larici-populina; one was M. medusae. M. larici-populina urediniospores were 32 to 48 μm long and possessed a characteristic apical bald spot. DNA was extracted from aecia and uredinia, and the internal transcribed spacer (ITS) of the ribosomal RNA gene was amplified in real-time polymerase chain reaction (PCR) by specific primers for M. medusae or M. larici-populina created from sequences (GenBank Accession Nos. AY429656 and AY429657). The 120 base pairs target fragments amplified only with the M. larici-populina specific primers with the 14 samples that were identified as M. larici-populina by morphological characteristics of the urediniospores. No PCR amplification was obtained with M. medusae primers. These results were not unexpected since larch has been previously reported as an aecial host of M. larici-populina elsewhere (2). The ability of M. larici-populina to overwinter and complete its life cycle has important consequences since it proves that it is established and can go through sexual reproduction. A complete life cycle in eastern North America may allow M. larici-populina to generate pathogenic variation that will challenge poplar breeders in this region. References: (1) L. Innes et al. Plant Dis. 88:85, 2004. (2) G. Newcombe et al. Plant Dis. 78:1218, 1994.

scholarly journals Street Tree Diversity in Eastern North America and Its Potential for Tree Loss to Exotic Borers

2006 ◽  
Vol 32 (6) ◽  
pp. 297-304
Author(s):  
Michael Raupp ◽  
Anne Cumming ◽  
Erin Raupp
Keyword(s):  
North America ◽  
Urban Forest ◽  
Insect Pest ◽  
Emerald Ash Borer ◽  
Urban Forests ◽  
Dutch Elm Disease ◽  
Eastern North America ◽  
Longhorned Beetle ◽  
Asian Longhorned Beetle ◽  
Generic Level

In light of catastrophic tree losses caused by Dutch elm disease, foresters recommended that the urban forest be diversified. The intent was to create a more sustainable urban forest that would not be decimated by a single pathogen or insect pest. However, recent introductions of deadly borers such as Asian longhorned beetle and emerald ash borer reveal that new introductions can have disastrous consequences for urban forests. An analysis of tree inventories from 12 cities in eastern North America reveals an overabundance of certain genera of trees such as Acer and Fraxinus. Introduced pests with broad host ranges such as the Asian longhorned beetle may be capable of killing or forcing intervention on large numbers of trees. Even cities that have diversified at a low taxonomic level (cultivar or species) may suffer greatly from the depredations of insect pests such as the emerald ash borer that specialize on plants at the generic level. Generalists capable of feeding on plants in several families will create problems for urban forests even when attempts have been made to diversify at higher taxonomic levels. Urban foresters should avoid planting susceptible taxa of trees, especially in cities that are overstocked in these taxa, and consider diversifying greatly the types of trees in cities.

Sign in / Sign up

Export Citation Format

Share Document