Two species in the Ceratocystis coerulescens complex from conifers in western North America

1997 ◽  
Vol 75 (5) ◽  
pp. 827-834 ◽  
Author(s):  
Michael J. Wingfield ◽  
Thomas C. Harrington ◽  
Halvor Solheim
Keyword(s):  
North America ◽  
Bark Beetle ◽  
Picea Glauca ◽  
Primary Component ◽  
Western North America ◽  
Dendroctonus Rufipennis ◽  
Engelmann Spruce ◽  
The North ◽  
Blue Stain ◽  
High Degree

Two species of Ceratocystis are described from western North America. Ceratocystis rufipenni Wingfield, Harrington, & Solheim is associated with the North American spruce bark beetle Dendroctonus rufipennis infesting both Engelmann spruce (Picea engelmannii Parry) and white spruce (Picea glauca (Moench) Voss) in British Columbia. This fungus is a primary component of the bark beetle mycota and has a relatively high degree of virulence to Engelmann spruce. Ceratocystis douglasii (Davidson) Wingfield & Harrington was previously described as Endoconidiophora coerulescens f. douglasii. It is common on Douglas-fir lumber in western North America where it causes blue stain. Both fungi grow optimally at low temperatures and produce perithecia only after extended incubation under refrigeration. Ceratocystis rufipenni produces conidiophores mostly in association with perithecia, whereas conidia and conidiophores of C. douglasii are produced abundantly on wood and agar. Key words: Ceratocystis, Chalara, Dendroctonus, Ophiostoma, bark beetle – fungus interactions, symbiosis.

scholarly journals Influence of ENSO on North American subseasonal surface air temperature variability

2021 ◽  
Vol 2 (2) ◽  
pp. 395-412
Author(s):  
Patrick Martineau ◽  
Hisashi Nakamura ◽  
Yu Kosaka
Keyword(s):  
North America ◽  
Air Temperature ◽  
North American ◽  
Surface Air Temperature ◽  
Tropical Pacific ◽  
La Niña ◽  
Western North America ◽  
The North ◽  
Subseasonal Variability ◽  
La Nina

Abstract. The wintertime influence of tropical Pacific sea surface temperature (SST) variability on subseasonal variability is revisited by identifying the dominant mode of covariability between 10–60 d band-pass-filtered surface air temperature (SAT) variability over the North American continent and winter-mean SST over the tropical Pacific. We find that the El Niño–Southern Oscillation (ENSO) explains a dominant fraction of the year-to-year changes in subseasonal SAT variability that are covarying with SST and thus likely more predictable. In agreement with previous studies, we find a tendency for La Niña conditions to enhance the subseasonal SAT variability over western North America. This modulation of subseasonal variability is achieved through interactions between subseasonal eddies and La Niña-related changes in the winter-mean circulation. Specifically, eastward-propagating quasi-stationary eddies over the North Pacific are more efficient in extracting energy from the mean flow through the baroclinic conversion during La Niña. Structural changes of these eddies are crucial to enhance the efficiency of the energy conversion via amplified downgradient heat fluxes that energize subseasonal eddy thermal anomalies. The enhanced likelihood of cold extremes over western North America is associated with both an increased subseasonal SAT variability and the cold winter-mean response to La Niña.

A New Gunnel, Pholis clemensi, from the Coast of Western North America

1964 ◽  
Vol 21 (5) ◽  
pp. 933-939 ◽  
Author(s):  
Richard H. Rosenblatt
Keyword(s):  
British Columbia ◽  
New Species ◽  
North America ◽  
North American ◽  
North American Species ◽  
Western North America ◽  
The North ◽  
The Family ◽  
Juan De Fuca ◽  
A New Species

A new species, Pholis clemensi, referred to the family Pholidae, is named and described from 12 specimens taken in southern British Columbia waters and the Strait of Juan de Fuca. Pholis clemensi is compared with other members of the genus, and a key is given to the North American species.

scholarly journals Infection of Engelmann-Spruce Seed by Geniculodendron Pyriforme in Western North America

Mycologia ◽  
1980 ◽  
Vol 72 (2) ◽  
pp. 406-410 ◽  
Author(s):  
M. C. Wicklow-Howard ◽  
J. Skujins
Keyword(s):  
North America ◽  
Western North America ◽  
Engelmann Spruce

The Impact of Sea Surface Temperature Biases on North American Precipitation in a High-Resolution Climate Model

2020 ◽  
Vol 33 (6) ◽  
pp. 2427-2447 ◽  
Author(s):  
Nathaniel C. Johnson ◽  
Lakshmi Krishnamurthy ◽  
Andrew T. Wittenberg ◽  
Baoqiang Xiang ◽  
Gabriel A. Vecchi ◽  
...  
Keyword(s):  
North America ◽  
Surface Temperature ◽  
North Atlantic ◽  
North American ◽  
North Pacific ◽  
Climate Model ◽  
Sea Surface ◽  
Tropical Atlantic ◽  
Western North America ◽  
The North

AbstractPositive precipitation biases over western North America have remained a pervasive problem in the current generation of coupled global climate models. These biases are substantially reduced, however, in a version of the Geophysical Fluid Dynamics Laboratory Forecast-Oriented Low Ocean Resolution (FLOR) coupled climate model with systematic sea surface temperature (SST) biases artificially corrected through flux adjustment. This study examines how the SST biases in the Atlantic and Pacific Oceans contribute to the North American precipitation biases. Experiments with the FLOR model in which SST biases are removed in the Atlantic and Pacific are carried out to determine the contribution of SST errors in each basin to precipitation statistics over North America. Tropical and North Pacific SST biases have a strong impact on northern North American precipitation, while tropical Atlantic SST biases have a dominant impact on precipitation biases in southern North America, including the western United States. Most notably, negative SST biases in the tropical Atlantic in boreal winter induce an anomalously strong Aleutian low and a southward bias in the North Pacific storm track. In boreal summer, the negative SST biases induce a strengthened North Atlantic subtropical high and Great Plains low-level jet. Each of these impacts contributes to positive annual mean precipitation biases over western North America. Both North Pacific and North Atlantic SST biases induce SST biases in remote basins through dynamical pathways, so a complete attribution of the effects of SST biases on precipitation must account for both the local and remote impacts.

Early Eocene (Ypresian) birds from the Okanagan Highlands, British Columbia (Canada) and Washington State (USA)

2019 ◽  
Vol 56 (8) ◽  
pp. 803-813
Author(s):  
Gerald Mayr ◽  
S. Bruce Archibald ◽  
Gary W. Kaiser ◽  
Rolf W. Mathewes
Keyword(s):  
British Columbia ◽  
North America ◽  
Fossil Record ◽  
Washington State ◽  
Fossil Birds ◽  
Early Eocene ◽  
Western North America ◽  
Postcranial Skeleton ◽  
The North ◽  
Okanagan Highlands

We survey the known avian fossils from Ypresian (early Eocene) fossil sites of the North American Okanagan Highlands, mainly in British Columbia (Canada). All specimens represent taxa that were previously unknown from the Eocene of far-western North America. Wings from the McAbee site are tentatively referred to the Gaviiformes and would constitute the earliest fossil record of this group of birds. A postcranial skeleton from Driftwood Canyon is tentatively assigned to the Songziidae, a taxon originally established for fossils from the Ypresian of China. Two skeletons from Driftwood Canyon and the McAbee site are tentatively referred to Coliiformes and Zygodactylidae, respectively, whereas three further fossils from McAbee, Blakeburn, and Republic (Washington, USA) are too poorly preserved for even a tentative assignment. The specimens from the Okanagan Highlands inhabited relatively high paleoaltitudes with microthermal climates (except Quilchena: lower mesothermal) and mild winters, whereas most other Ypresian fossil birds are from much warmer lowland paleoenvironments with upper mesothermal to megathermal climates. The putative occurrence of a gaviiform bird is particularly noteworthy because diving birds are unknown from other lacustrine Ypresian fossil sites of the Northern Hemisphere. The bones of the putative zygodactylid show a sulphurous colouration, and we hypothesize that this highly unusual preservation may be due to the metabolic activity of sulphide-oxidizing bacteria.

Corticolous species of Protoparmelia (lichenized Ascomycotina) in North America

2005 ◽  
Vol 83 (9) ◽  
pp. 1075-1081 ◽  
Author(s):  
Irwin M. Brodo ◽  
André Aptroot
Keyword(s):  
North America ◽  
North American ◽  
Western North America ◽  
The North ◽  
First Time ◽  
Lichen Flora

Protoparmelia hypotremella van Herk, Spier & V. Wirth is reported here as an addition to the North American lichen flora. Fertile material of P. hypotremella was found for the first time, and it is described in detail. The hyaline hair-like appendages on both polar ends of the ascospores, characteristic of the genus, are illustrated for the first time. The species is then compared with Protoparmelia ochrococca , known from western North America, and Protoparmelia oleagina , still known only from Europe. A key to the corticolous species of Protoparmelia is provided.

B Chromosomes in White Spruce

1977 ◽  
Vol 198 (1133) ◽  
pp. 325-344 ◽  
Keyword(s):  
North America ◽  
Picea Glauca ◽  
Constitutive Heterochromatin ◽  
White Spruce ◽  
B Chromosomes ◽  
Experimental Results ◽  
The Other ◽  
Differential Mortality ◽  
X Chromosomes ◽  
Engelmann Spruce

In Picea glauca , the White Spruce, supernumerary, B chromosomes were found in 48 out of 51 North American populations investigated. The B chromosomes are of two kinds. The more common (B1) is metacentric. The other (B2) has a subterminal centromere. Giemsa staining at metaphase shows no trace of constitutive heterochromatin in B chromosomes, yet at interphase the B chromosomes are heteropycnotic. It is argued that the capacity for heterochromatization of the B chromosomes at interphase may be associated with gene inactivation as in the X chromosomes of female mammals. B2 is found in western regions only, i. e. west of the 95th meridian. B1 is found in both western and eastern regions but its frequency varies substantially among populations. In general there is a reduction in B frequency from east to west in both western and eastern regions of North America. Experimental results support the view that such variation is adaptive and, in part at least, caused by the differential mortality of plants with and without B chromosomes in particular environments. Evidence is presented which indicates that B2 was introduced into White Spruce following hybridization with Engelmann Spruce.

scholarly journals An anomalous atmospheric river linked to the late June 2021 western North America heatwave

2022 ◽  
Author(s):  
Ruping Mo ◽  
Hai Lin ◽  
Frédéric Vitart
Keyword(s):  
North America ◽  
Water Vapour ◽  
Warm Season ◽  
Lower Troposphere ◽  
Heavy Precipitation ◽  
Cold Season ◽  
Feedback Mechanism ◽  
Western North America ◽  
Water Vapour Flux ◽  
The North

Abstract Atmospheric rivers (ARs) are long and narrow bands of enhanced water vapour flux concentrated in the lower troposphere. Many studies have documented the important role of cold-season ARs in producing heavy precipitation and triggering extreme flooding in many parts of the world. However, relatively little research has been conducted on the warm-season ARs and their impacts on extreme heatwave development. Here we show an anomalous warm-season AR moving across the North Pacific and its interaction with the western North American heatwave in late June 2021. We call it an “oriental express’’ to highlight its capability to transport tropical moisture to the west coast of North America from sources in Southeast Asia. Its landfall over the Alaska Panhandle lasted for more than two days and resulted in significant spillover of moisture into western Canada. We provide evidence that the injected water vapour was trapped under the heat dome and may have formed a positive feedback mechanism to regulate the heatwave development in western North America.

scholarly journals The impact of bark beetle infestation on monoterpene emissions and secondary organic aerosol formation in Western North America

2012 ◽  
Vol 12 (11) ◽  
pp. 29763-29800 ◽  
Author(s):  
A. R. Berg ◽  
C. L. Heald ◽  
K. E. Huff Hartz ◽  
A. G. Hallar ◽  
A. J. H. Meddens ◽  
...  
Keyword(s):  
United States ◽  
British Columbia ◽  
North America ◽  
Bark Beetle ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Western United States ◽  
Mortality Data ◽  
Western North America ◽  
The Impact

Abstract. Over the last decade, extensive beetle outbreaks in Western North America have destroyed over 100 000 km2 of forest throughout British Columbia and the Western United States. Beetle infestations impact monoterpene emissions through both decreased emissions as trees are killed (mortality effect) and increased emissions in trees under attack (attack effect). We use 14 yr of beetle mortality data together with beetle-induced monoterpene concentration data in the National Center for Atmospheric Research (NCAR) Community Earth System Model (CESM) to investigate the impact of beetle mortality and attack on monoterpene emissions and secondary organic aerosol (SOA) formation in Western North America. Regionally, beetle infestations may have a significant impact on monoterpene emissions and SOA concentrations, with up to a 4-fold increase in monoterpene emissions and up to a 40% increase in SOA concentrations in some years (following a scenario where the attack effect is based on observed lodgepole pine response). Responses to beetle attack depend on the extent of previous mortality and the number of trees under attack in a given year, which can vary greatly over space and time. Simulated enhancements peak in 2004 (British Columbia) and 2008 (US). Responses to beetle attack are shown to be substantially larger (up to a 3-fold localized increase in SOA concentrations) when following a scenario based on bark-beetle attack in spruce trees. Placed in the context of observations from the IMPROVE network, the changes in SOA concentrations due to beetle attack are in most cases small compared to the large annual and interannual variability in total organic aerosol which is driven by wildfire activity in Western North America. This indicates that most beetle-induced SOA changes are not likely detectable in current observation networks; however these changes may impede efforts to achieve natural visibility conditions in the national parks and wilderness areas of the Western United States.

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