Notes on the Juniper Berry Mite, Trisetacus quadrisetus (Thomas) (Acarina: Eriophyidae), in British Columbia

1960 ◽  
Vol 92 (8) ◽  
pp. 608-610 ◽  
Author(s):  
C. V. G. Morgan ◽  
A. F. Hedlin

The juniper berry mite, Trisetacus (Eriophyes) quadrisetus (Thomas), was unknown in Canada until 1956, when its occurrence was noted on Rocky Mountain juniper, Juniperus scopulorum Sarg., in the Tzouhalem Indian Reserve near Duncan on Vancouver Island, B.C.; it has not been found elsewhere in the Province (Fig. 1). Material was first submitted to the authors by Mr. W. G. Ziller, Forest Biology Laboratory, Victoria, B.C. Each year almost the entire crop of berries on the only two trees in the area is destroyed by the mite; these trees are 30 and 50 feet high. In 1956 and 1957, no normal berries were observed. In 1959, only four healthy berries were found amongst 715 examined from the two trees. Such a heavy infestation indicates that seed production by these trees was practically eliminated since feeding by the mite destroys the seed.

1971 ◽  
Vol 8 (7) ◽  
pp. 788-801 ◽  
Author(s):  
M. J. Berry ◽  
W. R. Jacoby ◽  
E. R. Niblett ◽  
R. A. Stacey

Geophysical studies of the crust and upper mantle have been conducted in the Canadian Cordillera for over two decades, but only recently have sufficient data been collected to permit a synthesis and a correlation with the major geological units. The studies have included gravity, heat flow, and magnetotelluric observations, geomagnetic depth sounding, and high level aeromagnetics as well as both small and large scale refraction and reflection seismic surveys.It now appears that major crustal units may be recognized geophysically:(i) Seismic and gravity data suggest that the Plains and Rocky Mountains are underlain by two units of the North American craton with a crustal section 45–50 km thick. The northern unit appears to terminate at the Rocky Mountain Trench while the southern unit may extend to the Omineca Geanticline.(ii) The combined geological and geophysical data suggest that the Rocky Mountain Trench and possibly the Kootenay Arc near the 49th parallel mark the edge of the Precambrian continental margin and that the western Cordillera was formed by a complex succession of plate interactions with repeated reactivation of block boundaries.(iii) A combination of magnetic and heat flow data suggest that the region between the Rocky Mountain Trench and the Fraser Lineament is part of the Cordilleran Thermal Anomaly Zone recognized by Blackwell in the United States.(iv) Seismic data in Central British Columbia suggest that the Pinchi Fault system is a boundary between two crustal blocks.(v) The crustal thickness of the Coast Geanticline appears to increase gradually to the west to approximately 40 km and, at least in southern British Columbia, does not have a root zone below the mountains.(vi) The crustal section beneath Vancouver Island is abnormally thick and there is some paleomagnetic data which suggest that the Island may not have been formed in its present position, contiguous to the Cordillera. The crustal section for the northern part of the Insular Trough is significantly thinner.(vii) The active spreading of the Juan de Fuca Rise – Explorer Trench is now well documented. The geophysical data suggest active subduction of the Juan de Fuca plate beneath Oregon, Washing-ton, and southern Vancouver Island. However, further north there is no evidence for subduction.


2018 ◽  
Vol 603 ◽  
pp. 189-200 ◽  
Author(s):  
WD Halliday ◽  
MK Pine ◽  
APH Bose ◽  
S Balshine ◽  
F Juanes

2013 ◽  
Vol 14 (2) ◽  
pp. 85-88
Author(s):  
D. J. Regan ◽  
K. J. Woodruff ◽  
A. S. Davis

1957 ◽  
Vol 89 (1) ◽  
pp. 1-5 ◽  
Author(s):  
J. D. Gregson

Tick paralysis continues to be one of the most baffling and fascinating tickborne diseases in Canada. It was first reported in this country by Todd in 1912. Since then about 250 human cases, including 28 deaths, have been recorded from British Columbia. Outbreaks in cattle have affected up to 400 animals at a time, with losses in a herd as high as 65 head. Although the disease is most common in the Pacific northwest, where it is caused by the Rocky Mountain wood tick, Dermacentor andersoni Stiles, it has lately been reported as far south as Florida and has been produced by Dermacentor variabilis Say, Amblyomma maculatum Koch, and A. americanum (L.) (Gregson, 1953). The symptoms include a gradual ascending symmetrical flaccid paralysis. Apparently only man, sheep, cattle, dogs, and buffalo (one known instance) are susceptible, but even these may not necessarily be paralysed.


2004 ◽  
Vol 101 (49) ◽  
pp. 17258-17263 ◽  
Author(s):  
S. E. Kidd ◽  
F. Hagen ◽  
R. L. Tscharke ◽  
M. Huynh ◽  
K. H. Bartlett ◽  
...  

1990 ◽  
Vol 68 (9) ◽  
pp. 1880-1895 ◽  
Author(s):  
R. Deedee Kathman

Thirty-one species of eutardigrades were collected on five mountains on Vancouver Island, British Columbia, during July 1986 and July 1987. Three of the species found were new to science, including 1 species, Platicrista cheleusis n.sp., described herein and 2 species described elsewhere, and 21 others are new to British Columbia; 13 of these are also new to Canada.


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