CYTOTAXONOMY OF CIRSIUM HOOKERIANUM AND RELATED SPECIES

1965 ◽  
Vol 43 (5) ◽  
pp. 597-613 ◽  
Author(s):  
R. J. Moore ◽  
C. Frankton

The morphology and distribution of Cirsium hookerianum, a species almost entirely Canadian, and of four related species of the western United States (C. tweedyi, C. scopulorum, C. eatonii, and C. × clavatum) are described and the evolution of the group is discussed. Chromosome counts are reported for C. hookerianum, 2n = 34, 34 + 2 accessories; C. scopulorum, 2n = 34, 34 + 2 accessories; C. tweedyi, 2n = 34. A population of hybrids between C. hookerianum and C. undulatum in British Columbia is described.

2015 ◽  
Author(s):  
Iain J Reid

Since the 1900s, dinosaur fossils have been discovered from Jurassic to Cretaceous age strata, from all across the prairie provinces of Canada and the Western United States, yet little material is known from the outer provinces and territories. In British Columbia, fossils have long been uncovered from the prevalent mid-Cambrian Burgess Shale, but few deposits date from the Mesozoic, and few of these are dinosaurian. The purpose of this paper is to review the history of dinosaurian body fossils in British Columbia. The following dinosaurian groups are represented: coelurosaurians, thescelosaurids, iguanodontians, ankylosaurs and hadrosaurs.


Author(s):  
David Ehrenfeld

When we arrived in Vancouver at the start of our vacation, the tabloid headline at the newspaper stand caught our attention. “World’s Bravest Mom,” it shrieked. We stopped to read. The story was simple; it needed no journalistic embellishment. Dusk, August 19, 1996. Mrs. Cindy Parolin is horseback riding with her four children in Tulameen, in southern British Columbia’s Okanagan region. Without warning, a cougar springs out of the vegetation, hurtling at the neck of one of the horses. In the confusion, Steven Parolin, age six, falls off his horse and is seized by the cougar. Mrs. Parolin, armed only with a riding crop, jumps off her horse and challenges the cougar, which drops the bleeding child and springs at her. Ordering her other children to take their wounded brother and go for help, Mrs. Parolin confronts the cougar alone. By the time rescuers reach her an hour later, she is dying. The cat, shot soon afterward, was a small one, little more than sixty pounds. Adult male cougars can weigh as much as 200 pounds, we learn the next day from the BC Environment’s pamphlet entitled “Safety Guide to Cougars.” We are on our way to Garibaldi Provincial Park, where we plan to do some hiking, and have stopped in the park head-quarters for information. “Most British Columbians live all their lives without a glimpse of a cougar, much less a confrontation with one,” says the pamphlet, noting that five people have been killed by cougars in British Columbia in the past hundred years. (Actually, the number is now higher; cougar attacks have become increasingly common in the western United States and Canada in recent years.) “Seeing a cougar should be an exciting and rewarding experience, with both you and the cougar coming away unharmed.”However, the pamphlet notes, cougars seem to be attracted to children as prey, possibly because of “their high-pitched voices, small size, and erratic movements.” When hiking, “make enough noise to prevent surprising a cougar . . . carry a sturdy walking stick to be used as a weapon if necessary,” and “keep children close-at-hand and under control.”


Weed Science ◽  
1984 ◽  
Vol 32 (S1) ◽  
pp. 7-12 ◽  
Author(s):  
Donald C. Thill ◽  
K. George Beck ◽  
Robert H. Callihan

Downy brome (Bromus tectorumL. # BROTE), also known as cheatgrass, downy chess, broncograss, Mormon oats, and junegrass, was introduced into the United States from Europe, apparently during the middle of the nineteenth century (11, 21). According to Mack (23), downy brome entered British Columbia, Washington, and Utah around 1890; and by 1928 it had reached its present range, occupying much of the perennial grassland in Washington, Idaho, Oregon, Nevada, Utah, and British Columbia. Today, downy brome is a widespread weed throughout most of Canada, Mexico, and the United States, except for the southeastern United States (5, 17). Some consider downy brome to be an important forage because it provides most of the early spring grazing for livestock in western United States rangeland (21). However, it is also considered a troublesome weed in rangeland (31), winter wheat (Triticum aestivumL.) (27), several other crops (29), and noncropland (32).


1977 ◽  
Vol 109 (12) ◽  
pp. 1549-1554 ◽  
Author(s):  
Leonard A. Kelton

AbstractOrthops rubricatus (Fallén), a European species now known to occur in North America, is transferred to the genus Pinalitus Kelton. Pinalitus solivagus (Van Duzee) is reported from British Columbia, and P. utahensis Knight and P. brevirostris Knight are considered to be synonyms of it. Pinalitus rostratus n. sp. is described from Canada and western United States. Pinalitus californicus Knight is transferred to the genus Proba Distant. A key to species is provided.


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 ◽  
...  

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.


1960 ◽  
Vol 38 (1) ◽  
pp. 87-91
Author(s):  
L. Gilbertson

Poria zonata Bres., a wood-rotting fungus known only from the western United States and British Columbia, is reported to be widely distributed within that area on recently fallen trees of Abies grandis, A. concolor, A. lasiocarpa, Larix occidentalis, Pseudotsuga menziesii, and Tsuga heterophylla. A description of the sporophores of the fungus, its cultural characteristics, and the white pocket rot caused by it are given.


1980 ◽  
Vol 17 (9) ◽  
pp. 1125-1140 ◽  
Author(s):  
W. Douglas Stewart ◽  
Roger G. Walker

The Pennsylvanian Rocky Mountain Supergroup, in the Elk Range, B.C., includes three sandstone formations: Tyrwhitt (about 100 m thick), Storelk (about 95 m), and Tobermory (about 75). The Tyrwhitt consists mostly of structureless sandstones which prove to be bioturbated in X radiographs. There is an abundant trace fauna, as well as brachiopods. The second most abundant facies consists of medium scale (up to about 1 m) cross-bedded sandstones. The Tobermory is essentially similar to the Tyrwhitt but contains fewer structureless sandstones, and more beds with ripple cross-lamination and horizontal lamination. Both formations were probably deposited slowly in water deeper than fair-weather wave base (deeper than 10–15 m).The Storelk, sandwiched between Tyrwhitt and Tobermory, is dominated by large scale (up to 10.5 m) sets of cross-bedding. These occur in three members, separated by two structureless members. The Storelk structureless members are not mottled in X radiographs, and no trace fauna was found in the field. There is only one 1 m thick fossiliferous bed within the Storelk, which is otherwise barren of trace or body fossils. We reject fluvial and marine sandwave interpretations of the large scale cross-bedding, and suggest that the Storelk represents a coastal eolian dune complex. Paleoflow directions are dominantly toward south-southwest, similar to Pennsylvanian paleowind directions in the western United States. The Storelk structureless members possibly represent sand blown into standing bodies of water, one of which was connected to the open sea (the fossiliferous bed).


2013 ◽  
Vol 13 (6) ◽  
pp. 3149-3161 ◽  
Author(s):  
A. R. Berg ◽  
C. L. Heald ◽  
K. E. Huff Hartz ◽  
A. G. Hallar ◽  
A. J. H. Meddens ◽  
...  

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-induced tree mortality data together with beetle-induced monoterpene emission data in the National Center for Atmospheric Research (NCAR) Community Earth System Model (CESM) to investigate the impact of beetle-induced tree 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 (in 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 summertime SOA concentrations) in 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.


1969 ◽  
Vol 47 (7) ◽  
pp. 1085-1100 ◽  
Author(s):  
D. B. O. Savile

Ledum glandulosum extends northward from Western United States into southern British Columbia in and east of the Cascade Range and into extreme SE British Columbia and SW Alberta in the Rocky Mts. Further north, within the range of L. groenlandicum but beyond that of L. glandulosum, hybrids between the two species occur, notably in and near Banff National Park, indicating that L. glandulosum formerly extended further north. The hybrids form an irregular swarm among typical L. groenlandicum rather than a cline; for this reason, and because of numerous morphological and other distinctions, the taxa are maintained as species. L. groenlandicum and L. palustre ssp. decumbens overlap in Alaska, Yukon, and Mackenzie in a belt up to 700 miles wide. Six definite hybrids were detected out of ca. 300 specimens from the sympatric zone, and ca. 30 specimens showed signs of probable minor introgression. The marked sympatry with minimal hybridization makes it necessary to maintain L. groenlandicum at specific rank. A rust, Chrysomyxa ledicola, that freely attacks L. palustre ssp. decumbens and L. groenlandicum does not infect L. glandulosum, but it attacks the hybrids in the Banff region except those closely approaching L. glandulosum. Another rust, C. ledi, has developed morphologically distinct varieties each specialized to a single Ledum. In the Banff region hybrids have been found between C. ledi var. glandulosi and C. l. var. groenlandici on L. glandulosum × groenlandicum. C. ledi var. ledi, on L. palustre (including ssp. decumbens) is morphologically distinct from C. ledi var. groenlandici, further emphasizing the sharp distinctness of L. groenlandicum from L. palustre ssp. decumbens.


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