Journal articles: 'Northeastern North America'

1

Zack, Richard S. "Freshwater Macroinvertebrates of Northeastern North America." American Entomologist 37, no. 4 (1991): 247. http://dx.doi.org/10.1093/ae/37.4.247.

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Frank, J. H., N. M. Downie, and R. H. Arnett. "The Beetles of Northeastern North America." Florida Entomologist 79, no. 3 (September 1996): 471. http://dx.doi.org/10.2307/3495601.

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3

Smith, Douglas, and Paula Martin. "Freshwater Macroinvertebrates of Northeastern North America." Transactions of the American Fisheries Society 120, no. 1 (January 1, 1991): 130–32. http://dx.doi.org/10.1577/1548-8659-120.1.130.

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Lavitt, Tate H., and David L. Wagner. "A New CrypticEupsiliafrom Northeastern North America (Noctuidae)." Journal of the Lepidopterists’ Society 70, no. 3 (August 2016): 238–48. http://dx.doi.org/10.18473/107.070.0310.

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5

Brothers, Timothy S. "Postsettlement Plant Migrations in Northeastern North America." American Midland Naturalist 128, no. 1 (July 1992): 72. http://dx.doi.org/10.2307/2426414.

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6

Lothrop, Jonathan C., Darrin L. Lowery, Arthur E. Spiess, and Christopher J. Ellis. "Early Human Settlement of Northeastern North America." PaleoAmerica 2, no. 3 (July 2, 2016): 192–251. http://dx.doi.org/10.1080/20555563.2016.1212178.

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7

Hough, S. E., K. H. Jacob, and L. Seeber. "High-Frequency Seismic Wave Propagation in Northeastern North America." Seismological Research Letters 61, no. 3-4 (July 1, 1990): 193–208. http://dx.doi.org/10.1785/gssrl.61.3-4.193.

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Abstract A key element in the assessment of seismic hazard is the estimation of how energy propagation from a given earthquake is affected by crustal structure near the receiver and along the more distant propagation path. In this paper, we present data from a variety of sources in eastern North America recorded at epicentral distances of a few to 800 km, and characterize and interpret systematic features. Site effects have been classically considered in terms of amplification either within a sediment-filled valley or from a single topographic feature (Geli et al., 1988). We present evidence of high frequency (5–30 Hz) resonances observed in hard-rock recordings of both body waves and Lg waves, and suggest that site effect should be expanded regionally to include structural and topographic information over sufficiently large areas to include several wavelengths of any features that may interact with seismic waves in the frequency range of interest. A growing body of evidence suggests that ground motions at high frequencies recorded at large epicentral distances in eastern North America are controlled by resonance effects. We hypothesize that a fundamental difference between eastern and western North America spectra stems from a combination of differences in the character of topography and near-surface structure. Active tectonics of western North America gives rise to a complex crust that scatters seismic energy in a random manner and results in very effective attenuation of high frequencies. The older eastern North American crust contains scatterers that are more ordered, with characteristic length scales that give rise to resonance phenomena in the frequency band critical for earthquake hazard. We present preliminary analysis of topographic data from the Adirondack Mountains in New York that demonstrates the existence of characteristic length scales on the order of up to 1–3 kilometers. Features with these length scales will effectively scatter energy at frequencies in the 1 to 10 Hz range.

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Grise, Kevin M., Seok-Woo Son, and John R. Gyakum. "Intraseasonal and Interannual Variability in North American Storm Tracks and Its Relationship to Equatorial Pacific Variability." Monthly Weather Review 141, no. 10 (September 25, 2013): 3610–25. http://dx.doi.org/10.1175/mwr-d-12-00322.1.

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Abstract Extratropical cyclones play a principal role in wintertime precipitation and severe weather over North America. On average, the greatest number of cyclones track 1) from the lee of the Rocky Mountains eastward across the Great Lakes and 2) over the Gulf Stream along the eastern coastline of North America. However, the cyclone tracks are highly variable within individual winters and between winter seasons. In this study, the authors apply a Lagrangian tracking algorithm to examine variability in extratropical cyclone tracks over North America during winter. A series of methodological criteria is used to isolate cyclone development and decay regions and to account for the elevated topography over western North America. The results confirm the signatures of four climate phenomena in the intraseasonal and interannual variability in North American cyclone tracks: the North Atlantic Oscillation (NAO), the El Niño–Southern Oscillation (ENSO), the Pacific–North American pattern (PNA), and the Madden–Julian oscillation (MJO). Similar signatures are found using Eulerian bandpass-filtered eddy variances. Variability in the number of extratropical cyclones at most locations in North America is linked to fluctuations in Rossby wave trains extending from the central tropical Pacific Ocean. Only over the far northeastern United States and northeastern Canada is cyclone variability strongly linked to the NAO. The results suggest that Pacific sector variability (ENSO, PNA, and MJO) is a key contributor to intraseasonal and interannual variability in the frequency of extratropical cyclones at most locations across North America.

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9

Behan-Pelletier, Valerie M. "LIMNOZETES (ACARI: ORIBATIDA: LIMNOZETIDAE) OF NORTHEASTERN NORTH AMERICA." Canadian Entomologist 121, no. 6 (June 1989): 453–506. http://dx.doi.org/10.4039/ent121453-6.

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AbstractThe species of Limnozetes of northeastern North America are treated. A new generic diagnosis is given. Eight new species are described: L. latilamellata, L. guyi, L. borealis, L. onondaga, L. amnicus, and L. palmerae on the basis of adults and immatures, and L. lustrum and L. atmetos on the basis of adults. Identification of adults and immatures of these species is presented in tabular format. The range of morphological variation exhibited by these species is discussed. Transformation series for eight character states in Limnozetes are hypothesized on the basis of comparison with Hydrozetes. A key is given to the adults of the nine species of Limnozetes recorded from northeastern North America.

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10

Wolff, S. L., and R. L. Jefferies. "Taxonomic status of diploid Salicornia europaea (s.l.) (Chenopodiaceae) in northeastern North America." Canadian Journal of Botany 65, no. 7 (July 1, 1987): 1420–26. http://dx.doi.org/10.1139/b87-196.

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The taxonomic status of diploid Salicornia europaea L. (s.l.) in northeastern North America has been evaluated based on morphological and electrophoretic variation within and between populations. Populations of two European diploid micro-species, S. ramosissima J. Woods and S. europaea (s.s.), and populations of the midwestern diploid, S. rubra A. Nels., were also examined, affording a comparison between North American S. europaea (s.l.) and recognized species. Anther length, width of the scarious border of the fertile segment, and floral perianth shape were used to subdivide North American diploid populations into two groups. These groups were morphologically distinct from S. rubra and the European microspecies. The electrophoretic profile was unique in each morphologically distinct group of populations of S. europaea (s.l.) in northeastern North America. Based on morphological, geographical, and electrophoretic differences, diploid populations of S. europaea (s.l.) from this region are assigned to one of the following two new species: S. maritima Wolff & Jefferies, sp.nov., and S. borealis Wolff & Jefferies, sp.nov. The tetraploids are retained in S. europaea (s.l.).

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11

Ebel, J. E. "The Seventeenth Century Seismicity of Northeastern North America." Seismological Research Letters 67, no. 3 (May 1, 1996): 51–68. http://dx.doi.org/10.1785/gssrl.67.3.51.

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12

Capers, Robert S., Kenneth D. Kimball, Kent P. McFarland, Michael T. Jones, Andrea H. Lloyd, Jeffrey S. Munroe, Guillaume Fortin, et al. "Establishing Alpine Research Priorities in Northeastern North America." Northeastern Naturalist 20, no. 4 (October 1, 2013): 559. http://dx.doi.org/10.1656/045.020.0406.

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13

Fenton, William N. "Leadership in the Northeastern Woodlands of North America." American Indian Quarterly 10, no. 1 (1986): 21. http://dx.doi.org/10.2307/1184154.

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14

Les, Donald H. "Aquatic and wetland plants of northeastern North America." Aquatic Botany 69, no. 1 (January 2001): 75–79. http://dx.doi.org/10.1016/s0304-3770(00)00136-4.

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15

Eid, Leroy V. ""National" War Among Indians of Northeastern North America." Canadian Review of American Studies 16, no. 2 (May 1985): 125–54. http://dx.doi.org/10.3138/cras-016-02-01.

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16

Morrison, Kenneth M. "Indians of Northeastern North America. Christian F. Feest." History of Religions 29, no. 1 (August 1989): 86. http://dx.doi.org/10.1086/463181.

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17

McLaughlin, J. A., and T. Hsiang. "Identification protocol for sixArmillariaspecies from northeastern North America." Canadian Journal of Forest Research 40, no. 3 (March 2010): 536–48. http://dx.doi.org/10.1139/x10-015.

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DNA sequences (~3 kb long) extending from the intergenic spacer 1 (IGS1) region to the 18S gene were obtained for isolates of Armillaria ostoyae , Armillaria calvescens , Armillaria gallica , and Armillaria sinapina . Additional investigation of 16 A. ostoyae, 11 Armillaria gemina , 21 A. calvescens, 18 A. gallica, and 15 A. sinapina isolates produced 117 sequences spanning the 3′ end of the IGS1 through the 5S gene and into the 5′ end of the IGS2 region. Additional sequences spanning the 3′ IGS2 to 5′ 18S gene region were obtained for two A. ostoyae, three A. gemina, two A. calvescens, two A. gallica, and three A. sinapina isolates. This is the first report of complete IGS2 sequences from Armillaria spp. A species identification protocol involving species-specific primers and restriction fragment length polymorphism analysis was devised based on species-specific polymorphisms. The protocol successfully identified all 16 A. ostoyae, 11 A. gemina, three of three Armillaria mellea , 18 A. gallica, 14 of 15 A. sinapina (11/12 diploid and 3/3 haploid), and 14 of 21 A. calvescens (13/15 diploid and 1/6 haploid) isolates included in this study. To the best of our knowledge, this success rate has not been matched by other methods.

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18

Rafferty, Sean M. "Evidence of early tobacco in Northeastern North America?" Journal of Archaeological Science 33, no. 4 (April 2006): 453–58. http://dx.doi.org/10.1016/j.jas.2005.08.006.

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19

Hamelin, Richard C., Nicole Lecours, and Gaston Laflamme. "Molecular Evidence of Distinct Introductions of the European Race of Gremmeniella abietina into North America." Phytopathology® 88, no. 6 (June 1998): 582–88. http://dx.doi.org/10.1094/phyto.1998.88.6.582.

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The presence of the European (EU) race of Gremmeniella abietina var. abietina, the causal agent of Scleroderris canker of conifers, was first reported in North America in 1975 in the northeastern United States and subsequently in southern Quebec and Newfoundland during the late 1970s, where it quickly became established. We analyzed DNA profiles in samples from a historic collection of G. abietina var. abietina that included some of the first isolates of the EU race reported in the United States to test hypotheses concerning the G. abietina var. abietina epidemic in North America. Genetic diversity was partitioned by an analysis of molecular variance with haplotype frequencies and distances. Genetic differentiation was high between populations in continental North America and Newfoundland (between region differentiation, Φct = 0.665, P < 0.001). This result was not consistent with the hypothesis of a single introduction of the pathogen into the northeastern United States followed by secondary spread into northeastern Canada. In contrast, small levels of genetic differentiation were observed among continental North American populations (Φct = 0.047, P = 0.079), suggesting gene flow among these populations. A single haplotype of G. abietina var. abietina dominated the continental populations (80% of the isolates) but was absent from Newfoundland and Europe. Five haplotypes were found in the New-foundland population, all of which were either absent or very rare on the continent. Populations from continental North America clustered together and were distinct from a second cluster composed of European and Newfoundland populations. A phylogenetic analysis of the haplotypes indicated that some of the rare haplotypes may have derived from somatic mutations, whereas others probably occurred as the result of new introductions. The results are consistent with a scenario of distinct primary introductions of this pathogen into Newfoundland and continental eastern North America followed by secondary asexual propagation.

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20

Lassoie, J. P., W. S. Teel, and K. M. Davies Jr. "Agroforestry Research and Extension Needs For Northeastern North America." Forestry Chronicle 67, no. 3 (June 1, 1991): 219–26. http://dx.doi.org/10.5558/tfc67219-3.

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Most farms in the Northeast include wooded areas that exist either as woodlots, plantations, or fence rows. However, the degree to which these areas support a particular farm is highly variable — some being largely ignored, others contributing significantly to the farm's economic well-being. The current economic plight and ecological problems facing the agricultural sector across North America are forcing many farmers to look for alternatives to traditional farming and forestry practices. One possibility is the greater integration of trees directly into the farming system through the adoption of various agroforestry principles and practices. Promoting the adoption of agroforestry by farmers in the Northeast, however, will require developing new research data bases and modifying current extension delivery systems. Suggestions for accomplishing both are provided in this paper based on an assessment of the potential for agroforestry in New York State. Key words: Agroforestry, tree crops, nut trees, technology transfer, Cooperative Extension, marginal lands

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Britton, D. M. "A hybrid Isoetes, I. × harveyi, in northeastern North America." Canadian Journal of Botany 69, no. 3 (March 1, 1991): 634–40. http://dx.doi.org/10.1139/b91-085.

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Fifty-five Isoetes plants from 11 localities were uniformly 2n = 77. These plants were referable to I. harveyi A. A. Eaton, and exhibited hybrid vigour. SEM of spores of the type and other collections had polymorphic spores and exhibited a morphology that ranged from I. macrospora to I. tuckermanii, the putative parents. This common hybrid should be named I. ×harveyi A. A. Eaton pro sp. Key words: Isoetes, hybrid, cytology, SEM.

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22

Gregory McHone, J. "Broad-terrane Jurassic flood basalts across northeastern North America." Geology 24, no. 4 (1996): 319. http://dx.doi.org/10.1130/0091-7613(1996)024<0319:btjfba>2.3.co;2.

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23

Ellis, Christopher J., and Jonathan C. Lothrop. "Early Fluted-biface Variation in Glaciated Northeastern North America." PaleoAmerica 5, no. 2 (April 3, 2019): 121–31. http://dx.doi.org/10.1080/20555563.2019.1601473.

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Sangster, A. L., Michel Gauthier, and C. F. Gower. "Metallogeny of structural zones, Grenville Province, northeastern North America." Precambrian Research 58, no. 1-4 (October 1992): 401–26. http://dx.doi.org/10.1016/0301-9268(92)90127-a.

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25

Melo, Rita De, and Paul D. N. Hebert. "A taxonomic reevaluation of North American Bosminidae." Canadian Journal of Zoology 72, no. 10 (October 1, 1994): 1808–25. http://dx.doi.org/10.1139/z94-245.

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Prior morphological studies have led to the recognition of six species in the genus Bosmina from North America. The present study employed allozymic and morphological analyses to ascertain the taxonomic diversity of bosminids from 72 North American habitats. The results suggest the occurrence of 10 species, including representatives from four recognized subgenera. Populations assignable to Bosmina (Bosmina) longirostris s.l. were rare, but two newly described species in the subgenus Sinobosmina were common in the eastern half of the continent. Four species of the subgenus Eubosmina were detected, one of which is newly described, while a second species new to North America apparently represents a recent invasion from Eurasia. Two species of the subgenus Neobosmina were found in lakes from the northeastern portion of the continent, while a third species was restricted to southern sites.

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Hajek, Ann E. "Pathology and Epizootiology of Entomophaga maimaiga Infections in Forest Lepidoptera." Microbiology and Molecular Biology Reviews 63, no. 4 (December 1, 1999): 814–35. http://dx.doi.org/10.1128/mmbr.63.4.814-835.1999.

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SUMMARY The insect-pathogenic fungal pathogen Entomophaga maimaiga is endemic to northeastern Asia and was first found in North America in 1989. Due to repeated epizootics and spread within populations of the major forest defoliator in northeastern North America, the gypsy moth (Lymantria dispar), this pathogen has gained much notoriety. Although this pathogen was purposely introduced to North America for biological control of L. dispar in 1910 to 1911, it is questionable whether it became established at the time of release and then remained at innocuous levels until relatively recently. Alternatively, the fungal strain present in North America today could be a more recent accidental introduction. DNA analysis demonstrates that this pathogen differs significantly from North American members of the same species complex (the Lepidoptera-specific Entomophaga aulicae species complex), and, to date, isolates of this introduced pathogen display little heterogeneity in North America. Nonsusceptible lepidopteran larvae have been identified, and either E. maimaiga is unable to penetrate the cuticle or the fungus cannot survive within the hemocoel. In the latter case, although E. maimaiga grows as protoplasts lacking cell walls in the host hemolymph, glycoproteins on plasma membranes of the protoplasts could lead to host recognition. Epizootiological studies demonstrate a clear association between fungal activity and environmental moisture but little association with host density under hypothesized conditions of high fungal density. Prediction of the occurrence of epizootics is not yet possible. E. maimaiga is easily established in new areas by releasing azygospores, but the ability to use this pathogen further for biological control will depend, in large part, on the development of mass production systems.

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Malhi, Ripan S., Beth A. Schultz, and David Glenn Smith. "Distribution of Mitochondrial DNA Lineages among Native American Tribes of Northeastern North America." Human Biology 73, no. 1 (2001): 17–55. http://dx.doi.org/10.1353/hub.2001.0008.

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Cicerone, R. D., C. G. Doll, and M. N. Toksoz. "Scattering and Attenuation of Seismic Waves in Northeastern North America." Bulletin of the Seismological Society of America 101, no. 6 (December 1, 2011): 2897–903. http://dx.doi.org/10.1785/0120090216.

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Arnett, Ross H., N. M. Downie, and R. H. Arnett. "Comments on Book Review of "Beetles of Northeastern North America"." Florida Entomologist 80, no. 1 (March 1997): 102. http://dx.doi.org/10.2307/3495986.

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30

Santelmann, Mary V. "Cellulose mass loss in ombrotrophic bogs of northeastern North America." Canadian Journal of Botany 70, no. 12 (December 1, 1992): 2378–83. http://dx.doi.org/10.1139/b92-297.

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Profiles of cellulose mass loss were measured for six Sphagnum bogs in eastern North America as an index of decomposition rates. After 2 years, mass loss rates in the upper 5 cm of the profiles averaged 49% in hummocks, 52% in hollows where the water table was more than 5 cm below the surface, and 21% in hollows where the water table was within 5 cm of the surface. Hummock profiles were of three types: (i) mass loss highest at the surface, gradually decreasing to very low rates below the water table; (ii) mass loss highest at the surface, decreasing for 10 – 20 cm, with a second peak in the region of the water table; and (iii) mass loss low at the surface with a subsurface peak. Mass loss rates for all profiles reached minimum values below the water table, averaging 3% in hummocks and 5% in hollows after 2 years. Cellulose mass loss was quite variable in upper portions of the profiles; within-site variance was almost as great as between-site variance, reflecting similarity among these bogs and heterogeneity within each site. Analysis of variance of mass loss at the hummock surface showed no significant effect of site; however, contrasts among means showed that mass loss rates at the surface of hummocks of the northern (Newfoundland) bogs were significantly lower (p < 0.05) than those from the sites farthest south (in Nova Scotia and Maine). Key words: cellulose mass loss, Sphagnum bog, decomposition.

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31

Snodgrass, Joel W. "Science and Conservation of Vernal Pools in Northeastern North America." Phyllomedusa: Journal of Herpetology 6, no. 2 (December 1, 2007): 155. http://dx.doi.org/10.11606/issn.2316-9079.v6i2p155-158.

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Sealy, Spencer G., and Harry R. Carter. "Inland Occurrences of Dovekies in September in Northeastern North America." Northeastern Naturalist 11, no. 4 (December 2004): 375–82. http://dx.doi.org/10.1656/1092-6194(2004)011[0375:ioodis]2.0.co;2.

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Lemke, Ashley, and John O’Shea. "The Seasonality of Prehistoric Caribou Hunting in Northeastern North America." PaleoAmerica 3, no. 4 (October 2, 2017): 374–82. http://dx.doi.org/10.1080/20555563.2017.1380464.

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Lothrop, Jonathan C., and Zachary L. F. Singer. "Paleoindian Peoples and Landscapes of Northeastern North America: An Introduction." PaleoAmerica 3, no. 4 (October 2, 2017): 283–87. http://dx.doi.org/10.1080/20555563.2017.1384232.

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Fortin, David, and Scott F. Lamoureux. "Multidecadal hydroclimatic variability in northeastern North America since 1550 AD." Climate Dynamics 33, no. 2-3 (May 30, 2008): 427–32. http://dx.doi.org/10.1007/s00382-008-0422-6.

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Evers, David C., and Thomas A. Clair. "Mercury in Northeastern North America: A synthesis of Existing Databases." Ecotoxicology 14, no. 1-2 (March 2005): 7–14. http://dx.doi.org/10.1007/s10646-004-6255-0.

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Northam, F. E., and R. H. Callihan. "The Windgrasses(AperaAdans., Poaceae) in North America." Weed Technology 6, no. 2 (June 1992): 445–50. http://dx.doi.org/10.1017/s0890037x0003503x.

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Two introduced windgrass species have become crop weeds in North America. Common windgrass is a major weed of winter cereals in Europe and was first documented in North America in the early 1800s. It is a weed of roadsides and waste areas in the northeastern United States and in winter grain fields of southern Ontario and Michigan. Interrupted windgrass was first reported in North America approximately 90 yr ago; it is adapted to more arid sites than common windgrass and is distributed predominantly in the northwestern U.S.A. During the past 10 to 15 yr, interrupted windgrass has adversely affected winter grain and grass seed producers in the Pacific Northwest due to additional control costs.

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Patel, Nikisha R., Susan Fawcett, and Arthur V. Gilman. "Phegopteris excelsior (Thelypteridaceae): A New Species of North American Tetraploid Beech Fern." Novon, A Journal for Botanical Nomenclature 27, no. 4 (November 4, 2019): 211–18. http://dx.doi.org/10.3417/2019409.

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Since the 1970s, an apomictic tetraploid beech fern (genus Phegopteris (C. Presl) Fée) has been known in northeastern North America. Previously published isozyme data suggest that this lineage is of allopolyploid origin involving long beech fern (P. connectilis (Michx.) Watt.) but not broad beech fern (P. hexagonoptera (Michx.) Fée), as originally hypothesized. Its second progenitor remains unknown. We performed a principal components analysis of the apomict and its North American congeners to elucidate morphological differences between them. We recognize the apomictic tetraploid at specific rank as P. excelsior N. R. Patel & A. V. Gilman and provide an illustration, a range map, a list of exsiccatae, and a key to Phegopteris species of North America.

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Zhang, Honghai, and Thomas L. Delworth. "Detectability of Decadal Anthropogenic Hydroclimate Changes over North America." Journal of Climate 31, no. 7 (April 2018): 2579–97. http://dx.doi.org/10.1175/jcli-d-17-0366.1.

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Regional hydroclimate changes on decadal time scales contain substantial natural variability. This presents a challenge for the detection of anthropogenically forced hydroclimate changes on these spatiotemporal scales because the signal of anthropogenic changes is modest, compared to the noise of natural variability. However, previous studies have shown that this signal-to-noise ratio can be greatly improved in a large model ensemble where each member contains the same signal but different noise. Here, using multiple state-of-the-art large ensembles from two climate models, the authors quantitatively assess the detectability of anthropogenically caused decadal shifts in precipitation-minus-evaporation (PmE) mean state against natural variability, focusing on North America during 2000–50. Anthropogenic forcing is projected to cause detectable (signal larger than noise) shifts in PmE mean state relative to the 1950–99 climatology over 50%–70% of North America by 2050. The earliest detectable signals include, during November–April, a moistening over northeastern North America and a drying over southwestern North America and, during May–October, a drying over central North America. Different processes are responsible for these signals. Changes in submonthly transient eddy moisture fluxes account for the northeastern moistening and central drying, while monthly atmospheric circulation changes explain the southwestern drying. These model findings suggest that despite the dominant role of natural internal variability on decadal time scales, anthropogenic shifts in PmE mean state can be detected over most of North America before the middle of the current century.

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Chien, Yu-Tang, S. Y. Simon Wang, Yoshimitsu Chikamoto, Steve L. Voelker, Jonathan D. D. Meyer, and Jin-Ho Yoon. "North American Winter Dipole: Observed and Simulated Changes in Circulations." Atmosphere 10, no. 12 (December 7, 2019): 793. http://dx.doi.org/10.3390/atmos10120793.

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In recent years, a pair of large-scale circulation patterns consisting of an anomalous ridge over northwestern North America and trough over northeastern North America was found to accompany extreme winter weather events such as the 2013–2015 California drought and eastern U.S. cold outbreaks. Referred to as the North American winter dipole (NAWD), previous studies have found both a marked natural variability and a warming-induced amplification trend in the NAWD. In this study, we utilized multiple global reanalysis datasets and existing climate model simulations to examine the variability of the winter planetary wave patterns over North America and to better understand how it is likely to change in the future. We compared between pre- and post-1980 periods to identify changes to the circulation variations based on empirical analysis. It was found that the leading pattern of the winter planetary waves has changed, from the Pacific–North America (PNA) mode to a spatially shifted mode such as NAWD. Further, the potential influence of global warming on NAWD was examined using multiple climate model simulations.

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Brunton, Daniel F., and Donald M. Britton. "Isoetes ×echtuckerii, hyb. nov., a new triploid quillwort from northeastern North America." Canadian Journal of Botany 77, no. 11 (January 30, 2000): 1662–68. http://dx.doi.org/10.1139/b99-146.

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A new interspecific Isoetes hybrid, I. echinospora Dur. × I. tuckermanii A. Br., is described from northeastern North America by means of cytology and the scanning electron microscopy of spores. Isoetes ×echtuckerii D.F. Brunton and D.M. Britton, hyb. nov., is the name proposed for this taxon. It is triploid, produces only aborted, sterile spores and has spore ornamentation intermediate between that of its putative parents. Populations have been identified in eastern Canada and the adjacent United States of America growing in association with one or both parents in shallow, fresh water along oligotrophic lake and river shores. Key words: Isoetes ×echtuckerii, interspecific hybrid, Canada, United States of America.

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Nyland, Ralph D., Amy L. Bashant, Kimberly K. Bohn, and Jane M. Verostek. "Interference to Hardwood Regeneration in Northeastern North America: Controlling Effects of American Beech, Striped Maple, and Hobblebush." Northern Journal of Applied Forestry 23, no. 2 (June 1, 2006): 122–32. http://dx.doi.org/10.1093/njaf/23.2.122.

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Abstract When American beech (Fagus grandifolia Ehrh.), striped maple (Acer pensylvanicum L.), and hobblebush (Viburnum alnifolium Marsh.) become dense in the understory they interfere with regeneration of other species. This review identifies threshold levels that causeproblems in regenerating desirable hardwoods in northeastern North America, and summarizes methods for controlling the interference in conjunction with a reproduction method cutting. It also forwards some ideas about management based on information in published sources.

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Stager, J. Curt, Brendan Wiltse, Brian F. Cumming, Timothy C. Messner, Joshua Robtoy, and Sidney Cushing. "Hydroclimatic and cultural instability in northeastern North America during the last millennium." PLOS ONE 16, no. 3 (March 26, 2021): e0248060. http://dx.doi.org/10.1371/journal.pone.0248060.

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Long-term, large-scale perspectives are necessary for understanding climate variability and its effects on ecosystems and cultures. Tree ring records of the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA) have documented major hydroclimatic variability during the last millennium in the American West, but fewer continuous, high-resolution hydroclimate records of the MCA-LIA period are available for eastern North America, particularly during the transition from the MCA to the LIA (ca. A.D. 1250–1400). Diatoms (micro-algae with silica cell walls) in sediment cores from three Adirondack (NY, USA) lakes and a hiatus in a wetland peat deposit in the Adirondack uplands provide novel insights into the late Holocene hydroclimate history of the Northeast. These records demonstrate that two of the region’s most extreme decadal-scale droughts of the last millennium occurred ca. A.D. 1260–1330 and ca. A.D. 1360–1390 during a dry-wet-dry (DWD) oscillation in the Adirondacks that contributed to forest fires and desiccation of wetlands in New York and Maine. The bimodal drying was probably related to more extreme droughts farther west and coincided with major events in Iroquoian and Abenaki cultural history. Although the causes of the DWD oscillation in the Adirondacks remain uncertain, changing sea-surface temperatures and solar variability are likely to have played a role.

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Mead, Jim I., and Frederick Grady. "Ochotona (Lagomorpha) from Late Quaternary Cave Deposits in Eastern North America." Quaternary Research 45, no. 1 (January 1996): 93–101. http://dx.doi.org/10.1006/qres.1996.0009.

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AbstractPikas (Ochtona)—small gnawing mammals, related to rabbits—range today throughout parts of the Northern Hemisphere, but had a wider distribution during the Pleistocene. Nine caves from northeastern North America (a region not occupied by pikas today) have Pleistocene deposits containing remains of Ochotona. We examine 526 fossil specimens (ranging in age from approximately 850,000 to 8670 yr B.P.) from five of these caves. Two morphological forms of Ochotona lived in northeastern North America during the late Pleistocene—a large species (probably O. whartoni) and a small species (probably O. princeps).Ochotona of glacial age are not necessarily indicative of talus slopes and mesic communities. O. princeps-like of the Irvingtonian of West Virginia were living with an amphibian-reptilian assemblage found in the area today, implying winters not much, if at all, colder than at present. Late glacial and postglacial change in climate south of the ice sheets in effect would have isolated Ochotona in eastern North America, where they were unable to retreat to the west or north. Whereas western pika had the option of moving up in elevation, into boreal islands, eastern forms became restricted to ever-diminishing habitats, culminating in extinction and extirpation. Radiocarbon ages imply that Ochotona lived in eastern North America during the late Pleistocene (late Rancholabrean) and into the earliest Holocene. We describe the youngest remains of Ochotona in eastern North America and the youngest for the extinct large form, O. whartoni.

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Neuman, Robert B. "Late Ordovician (Ashgill) Foliomena fauna brachiopods from northeastern Maine." Journal of Paleontology 68, no. 6 (November 1994): 1218–34. http://dx.doi.org/10.1017/s0022336000034211.

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Foliomena folium (Barrande) and other very small, thin-shelled brachiopods from the Pyle Mountain Argillite in Aroostook County, Maine, provide the only record of the presence of the Foliomena fauna in North America. Associated fossils include numerous small trilobites and a few specimens of other groups. An Ashgill age is established by the presence of graptolites of the Climacograptus spiniferous Zone in the underlying Winterville Formation.Most of the 190 specimens are small strophomenaceans and plectambonitaceans. One of the most numerous is the christianiid Nubialba forbesi n. gen. and sp. that has ribs and elaborately developed internal features. In the absence of evidence to contradict previous interpretations that the Foliomena fauna records cold-water environments, the presence of one or more deep basins along the southeastern margin of the trans-equatorial North American paleoplate occupied by cool peri-Gondwanan waters during a short segment of Ashgill time is implied.

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Titus, Kimberly, and Mark R. Fuller. "Recent Trends in Counts of Migrant Hawks from Northeastern North America." Journal of Wildlife Management 54, no. 3 (July 1990): 463. http://dx.doi.org/10.2307/3809660.

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Barry, R. G. "The nature and origin of climatic fluctuations in Northeastern North America." Géographie physique et Quaternaire 35, no. 1 (January 25, 2011): 41–47. http://dx.doi.org/10.7202/1000376ar.

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Features of the atmospheric circulation and climate of northeastern Canada are reviewed. In particular, the role of the upper level trough and its variability are discussed. It is shown that longitudinal displacements of the mean summer trough create anomalies of both air temperature and sea ice conditions in the region of Baffin Island. Climatic anomaly patterns in Labrador-Ungava and Keewatin associated with trough displacements are also summarized. Two examples of the application of such information to paleoclimat-ological questions are discussed. One concerns the influx of "exotic" tree pollen into Baffin Island and its previously postulated relationship to southerly airflow. It is concluded that pollen peaks cannot yet be reliably used as a paleowind index. The pattern of glacial inception and ice sheet extension during the Last Glacial Maximum is also briefly considered in the light of the available climatic information. Finally, the role of orbital variations affecting the seasonal pattern of solar radiation is discussed with reference to the last glacial cycle.

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Boatwright, J., and L. Seekins. "Regional Spectral Analysis of Three Moderate Earthquakes in Northeastern North America." Bulletin of the Seismological Society of America 101, no. 4 (August 1, 2011): 1769–82. http://dx.doi.org/10.1785/0120100225.

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Eiseman, Charles S., and David R. Smith. "New Sawfly (Hymenoptera: Argidae, Tenthredinidae) Host Records from Northeastern North America." Proceedings of the Entomological Society of Washington 122, no. 2 (May 11, 2020): 299. http://dx.doi.org/10.4289/0013-8797.122.2.299.

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Campbell, John L., Myron J. Mitchell, Peter M. Groffman, Lynn M. Christenson, and Janet P. Hardy. "Winter in northeastern North America: a critical period for ecological processes." Frontiers in Ecology and the Environment 3, no. 6 (August 2005): 314–22. http://dx.doi.org/10.1890/1540-9295(2005)003[0314:winnaa]2.0.co;2.

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Journal articles on the topic 'Northeastern North America'

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