scholarly journals THE BIOLOGY OF CANADIAN WEEDS.: 77.Veratrum viride Ait.

1987 ◽  
Vol 67 (3) ◽  
pp. 777-786 ◽  
Author(s):  
GERALD A. MULLIGAN ◽  
DEREK B. MUNRO
Keyword(s):  
North America ◽  
Chromosome Number ◽  
Biological Data ◽  
Eastern Canada ◽  
The West ◽  
Weed Biology ◽  
Herbaceous Perennial

This paper provides a summary of biological data on Veratrum viride Ait., false hellebore. It is a herbaceous perennial, native to wet habitats in North America. Subspecies viride occurs primarily in eastern Canada and subspecies eschscholtzii (A. Gray) Löve and Löve in the west. Both subspecies have the chromosome number of n = 16, 2n = 32. Ingested material of false hellebore is poisonous to humans and livestock.Key words: False hellebore, Veratrum viride Ait., weed biology

FERTILITY AND POLYPLOIDY OF EUPHORBIA CYPARISSIAS IN CANADA

1953 ◽  
Vol 31 (2) ◽  
pp. 152-163 ◽  
Author(s):  
R. J. Moore ◽  
D. R. Lindsay
Keyword(s):  
North America ◽  
Chromosome Number ◽  
Somatic Chromosome ◽  
Herbarium Specimens ◽  
Leaf Epidermis ◽  
Somatic Chromosome Number ◽  
Eastern Canada ◽  
European Species ◽  
Diploid Populations ◽  
Euphorbia Cyparissias

Euphorbia cyparissias L., a European species originally introduced into North America as an ornamental, is now firmly established on roadsides and pastures in Eastern Canada. The Canadian distribution is mapped from specimens in three herbaria. Plants with a somatic chromosome number of 20 and plants with the number 2n = 40 occur in eastern Ontario and adjacent Quebec. According to all available evidence for this region, the diploid plants never set seed, whereas the tetraploid populations are highly fertile. The cells of the upper leaf epidermis of the tetraploid plants are conspicuously larger than those of the diploid plants. By means of this criterion, the probable chromosome number of herbarium specimens was determined. The distribution of the diploid and tetraploid plants in Ontario and western Quebec is mapped. Tetraploid plants are known from eight locations in this area; five of these infestations are serious. It is believed that the sterility of the diploid populations is due to a genic condition which may interrupt normal pollen development.

THE BIOLOGY OF CANADIAN WEEDS.: 76. Vicia angustifolia L.,V. cracca L., V. sativa L., V. tetrasperma (L.) Schreb. and V. villosa Roth.

1986 ◽  
Vol 66 (3) ◽  
pp. 711-737 ◽  
Author(s):  
L. W. AARSSEN ◽  
IVAN V. HALL ◽  
K. I. N. JENSEN
Keyword(s):  
British Columbia ◽  
Biological Data ◽  
Crop Plants ◽  
Vicia Sativa ◽  
Coastal Regions ◽  
Eastern Canada ◽  
Weed Biology ◽  
Wide Range ◽  
Weedy Species ◽  
Vicia Cracca

This paper provides a summary of biological data on five weedy species of vetch (Vicia). All species are naturalized in Canada and are found in a wide range of habitats with their main centers of distribution in Eastern Canada and the south and coastal regions of British Columbia. Vicia cracca is the most common and serious problem and occurs nationwide. Vicia sativa is the most variable of the species; numerous subspecies, varieties, forms and hybrids are described. Tendrils allow vetches to attach to crop plants and form mat-like infestations. Vetch species are sensitive to a number of herbicides but there appears to be differential tolerance among species to chlorthal dimethyl, 2,4-DB and others. Vicia spp. are host to several economically important pathogens and parasites.Key words: Weed biology, vetches, Vicia spp., distribution

Trend analysis of fire season length and extreme fire weather in North America between 1979 and 2015

2017 ◽  
Vol 26 (12) ◽  
pp. 1009 ◽  
Author(s):  
Piyush Jain ◽  
Xianli Wang ◽  
Mike D. Flannigan
Keyword(s):  
North America ◽  
Statistical Significance ◽  
Kendall Test ◽  
Fire Season ◽  
Fire Weather ◽  
Season Length ◽  
Eastern Canada ◽  
Reanalysis Dataset ◽  
Fire Weather Index ◽  
Extreme Fire

We have constructed a fire weather climatology over North America from 1979 to 2015 using the North American Regional Reanalysis dataset and the Canadian Fire Weather Index (FWI) System. We tested for the presence of trends in potential fire season length, based on a meteorological definition, and extreme fire weather using the non-parametric Theil–Sen slope estimator and Mann–Kendall test. Applying field significance testing (i.e. joint significance of multiple tests) allowed the identification of the locations of significant trends, taking into account spatial correlations. Fire season length was found to be increasing over large areas of North America, especially in eastern Canada and the south-western US, which is consistent with a later fire season end and an earlier fire season start. Both positive and negative trends in potential fire spread days and the 99th percentile of FWI occurred in Canada and the contiguous United States, although the trends of largest magnitude and statistical significance were mostly positive. In contrast, the proportion of trends with significant decreases in these variables were much lower, indicating an overall increase in extreme fire weather. The smaller proportion of significant positive trends found over Canada reflects the truncation of the time series, necessary because assimilation of precipitation observations over Canada ceased in the reanalysis post-2002.

Climatic implications of latest Pleistocene and earliest Holocene mammalian sympatries in eastern Washington state, USA

2008 ◽  
Vol 70 (3) ◽  
pp. 426-432 ◽  
Author(s):  
R. Lee Lyman
Keyword(s):  
North America ◽  
Late Pleistocene ◽  
Rocky Mountains ◽  
Taxonomic Composition ◽  
Washington State ◽  
The West ◽  
Mammalian Faunas ◽  
Eastern Washington

AbstractFor more than fifty years it has been known that mammalian faunas of late-Pleistocene age are taxonomically unique and lack modern analogs. It has long been thought that nonanalog mammalian faunas are limited in North America to areas east of the Rocky Mountains and that late-Pleistocene mammalian faunas in the west were modern in taxonomic composition. A late-Pleistocene fauna from Marmes Rockshelter in southeastern Washington State has no modern analog and defines an area of maximum sympatry that indicates significantly cooler summers than are found in the area today. An earliest Holocene fauna from Marmes Rockshelter defines an area of maximum sympatry, including the site area, but contains a single tentatively identified taxon that may indicate slightly cooler than modern summers.

Conodonts as biostratigraphic tools for redefinition and correlation of the Cambrian–Ordovician Boundary

1988 ◽  
Vol 125 (4) ◽  
pp. 349-362 ◽  
Author(s):  
J. F. Miller
Keyword(s):  
North America ◽  
Boundary Point ◽  
Outer Part ◽  
Head Group ◽  
Eastern Canada ◽  
Green Point ◽  
Hierarchical Arrangement ◽  
Stratotype Section ◽  
Evolutionary Lineages ◽  
Zones And Subzones

AbstractThe Cambrian–Ordovician Boundary is recognized at different horizons on various continents by utilizing several fossil groups. Conodonts are abundant, diverse, and less provincial and facies-controlled than other fossils in this interval; many species are widespread and some are cosmopolitan. Strata representing the Cambrian–Ordovician Boundary interval from Asia, Australia, and North America can be correlated easily when those strata are from cratonal or shelf environments. Strata from slope facies have fewer conodonts, fewer taxa, and taxa may have different ranges compared with cratonal and shelf facies. It may be easier to correlate intercontinentally within cratonal/shelf facies than to correlate intracontinentally from cratonal/shelf facies to slope facies.A new hierarchical arrangement of conodont interval zones and subzones is proposed for western North America. These include the Proconodontus tenuiserratus Zone, the P. posterocostatus Zone (new), the P. muelleri Zone (new), the Eoconodontus Zone (new, with Eoconodontus notchpeakensis and Cambrooistodus minutus Subzones), the Cordylodus proavus Zone (emended, with Hirsutodontus hirsutus, Fryxellodontus inornatus, and Clavohamulus elongatus Subzones), the Cordylodus intermedius Zone (new, with Hirsutodontus simplex and Clavohamulus hintzei Subzones), the Cordylodus lindstromi Zone (new), and Cordylodus angulatus Zone (new).The boundary point for the base of the Ordovician System will be chosen so as to coincide with a correlatable conodont zonal boundary; other fossil groups will support correlation of this boundary point. Three alternative horizons are being considered. The base of the Cordylodus proavus Zone is the most distinctive but is regarded by some as older than is appropriate for the base of the Ordovician. The base of the Cordylodus intermedius Zone is recognizable by faunal changes in several evolutionary lineages at a level that is slightly younger than the presently recognized boundary in Australia, North America, and parts of Asia but slightly older than the base of the Tremadoc Series of Europe. The base of the C. lindstromi Zone can be recognized in most areas by the lowest occurrence of the nominate species, which is of questioned taxonomic validity and uncertain biostratigraphic utility; this horizon is closest to the base of the Tremadoc Series of Europe.Choice of a stratotype section has been narrowed to the Cow Head Group in Newfoundland, eastern Canada; and to the Fengshan and Yehli formations in Jilin Province, northeastern China. The Cow Head Group was deposited on and near the base of the continental slope. Erosion by debrisslide breccias resulted in a significant hiatus near the boundary interval in the Broom Point sections, a condition contrary to guidelines for choice of boundary sections. This may be less of a problem in other sections, such as Green Point. The Dayangcha section in China was deposited on the outer part of a continental shelf and has acritarchs, conodonts, graptolites and trilobites. Additional study of the China section is needed to document fully the ranges of critical conodont taxa.

The Lower Jurassic phosphorites of southeastern British Columbia and terrane accretion to western North America

1989 ◽  
Vol 26 (8) ◽  
pp. 1612-1616 ◽  
Author(s):  
T. P. Poulton ◽  
J. D. Aitken
Keyword(s):  
British Columbia ◽  
North America ◽  
Oceanic Crust ◽  
West Coast ◽  
Cold Water ◽  
Lower Jurassic ◽  
Depositional Model ◽  
Western North America ◽  
The West ◽  
Terrane Accretion

Sinemurian phosphorites in southeastern British Columbia and southwestern Alberta conform with the "West Coast type" phosphorite depositional model. The model indicates that they were deposited on or near the Early Jurassic western cratonic margin, next to a sea or trough from which cold water upwelled. This suggests that the allochthonous terrane Quesnellia lay well offshore in Sinemurian time. The sea separating Quesnellia from North America was partly floored by oceanic crust ("Eastern Terrane") and partly by a thick sequence of rifted, continental terrace wedge rocks comprising the Purcell Supergroup and overlying Paleozoic sequence. This sequence must have been depressed sufficiently that access of upwelling deep currents to the phosphorite depositional area was not impeded.

The Achievements of the Douglass Company in North America: 1758–1774

1982 ◽  
Vol 23 (2) ◽  
pp. 141-149 ◽  
Author(s):  
David D. Mays
Keyword(s):  
New York ◽  
North America ◽  
West Indies ◽  
Theatre History ◽  
The West ◽  
American Theatre ◽  
History Of ◽  
American Theatre History ◽  
A Company

On Monday, October 16, 1758., Hugh Gaine reported a novelty. “Friday last,” he told his readers in the New-York Mercury, “arrived here from the West Indies, a Company of Comedians; some Part of which were here in the Year 1753.” This brief notice, which went on to assure its readers that the company had “an ample Certificate of their Private as well as publick Qualifications,” marks the beginning of the most significant event in American theatre history: the establishment of the professional theatre on this continent. The achievements of the Company of Comedians during its sixteen-year residence in North America are virtually without parallel in the history of the theatre, and have not received sufficient recognition by historians and scholars.

NEW SPECIES OF DOLICHOPODIDAE FROM NORTH AMERICA AND THE WEST INDIES

1930 ◽  
Vol 62 (4) ◽  
pp. 84-87 ◽  
Author(s):  
M. C. van Duzee
Keyword(s):  
New Species ◽  
North America ◽  
West Indies ◽  
The West ◽  
Tarsal Joint ◽  
Pale Yellow ◽  
Posterior Pair ◽  
Snow White

Male: Length 2.6-3 mm. Head, thorax, abdomen, legs and feet thickly white pruinose, but the ground color showing through; face moderately wide, wholly pollinose, this pollen yellow in the middle, reaching the orbits at the suture, sides of upper part narrowly, below the suture widely white pollinose, sonsetimes the yellow pollen covers most of upper part and extends onto the inner part of the palpi; palpi with snow white pollen, each nearly as large as upper part of face; antennae wholly yellow, small, arista whitish; orbital cilia white, rather long on the sides; occiput, front, thorax and abdomen reddish coppery, posterior margins of abdominal segments sometimes green ; bristles of thorax small, black; hairs of ahdomen very short, white; pleura and coxae black with ground color nearly concealed with white pollen, tips of coxae yellow; hypopygium small, with a long, straight, black appendage extending forward under the abdomen and small yellowish appendages inside of this long one; femora, tibiae and tarsi pale yellow, last two joints of all tarsi blackish; the minute hairs on all femora and tibiae white, the small bristles on tibiae black; fore tibiae with a row of long white hairs on upper surface, which are as long as diameter of tibiae and extend to fourth tarsal joint, becoming shorter towards the end; apical joint of middle tarsi very slightly widened; pulvilli not enlarged ; joints of fore tarsi as 20-8-6-5-7 ; of middle ones as 32-14-9-6-6; joints of posterior pair as 25-19-11-6-7.

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