SAWFLY BIOLOGIES.: I. NEODIPRION TSUGAE MIDDLETON

1936 ◽  
Vol 68 (4) ◽  
pp. 71-79 ◽  
Author(s):  
Geo. R. Hopping ◽  
H. B. Leech
Keyword(s):  
British Columbia ◽  
Pacific Northwest ◽  
Western Hemlock ◽  
Queen Charlotte Islands ◽  
The Pacific

The western hemlock sawfly, Neodiprion tsugae Middleron, first came to our notice from the Queen Charlotte Islands, British Columbia. In 1931, reports of the dying of hemlocks over large areas came from rangers and timber operators of this region. A survey conducted by Mr. W. G. Mathers of the Dominion Entomological Branch, in September and October of that year, indicated that the injury extended over approximately forty square miles. In 1932, the outbreak showed definite signs of subsiding, and had practically disappeared by 1933, although many trees were killed during the peak year of 1931, indicating that this is a primary enemy of western hemlock, and that outbreaks may be expected from time to time in the Pacific Northwest.

Sediment transfer by shallow landsliding in the Queen Charlotte Islands, British Columbia

2002 ◽  
Vol 39 (2) ◽  
pp. 189-205 ◽  
Author(s):  
Yvonne Martin ◽  
Kenneth Rood ◽  
James W Schwab ◽  
Michael Church
Keyword(s):  
British Columbia ◽  
Pacific Northwest ◽  
Probability Distributions ◽  
Sampling Period ◽  
Sampling Bias ◽  
Drainage Basins ◽  
Physical Mechanisms ◽  
Queen Charlotte Islands ◽  
The Pacific ◽  
Sediment Transfer

Despite the importance of landsliding in routing sediment through mountainous drainage basins, few studies have documented landsliding rates over extended time and space scales. We have investigated landsliding in surficial material in the Queen Charlotte Islands using a large inventory of events, derived from aerial photography, covering an area of 166.7 km2. The mean erosion rate for shallow landsliding is 0.10 mm·a–1, which is at the upper end of shallow landsliding rates observed in the Pacific Northwest and coastal British Columbia, but several orders of magnitude lower than rock-based landsliding rates reported in the literature. Probability distributions for landslide area and volume are somewhat convex in form. Flattening of the curve found at low magnitudes may be due to sampling bias or physical mechanisms inhibiting failure, and the steepening for high values may exist because the sampling period is not long enough to adequately represent large events. Landslides generally initiate on hillslope gradients greater than 0.50–0.60. The largest numbers of landslides occur on south- to southwest-facing slopes and east- to northeast-facing slopes. Most events occur on concave and straight hillslopes in upper-slope positions. Landsliding rates were found not to be affected by rock type. Hillslopes in the Queen Charlotte Islands are often mantled by weathered Quaternary deposits and, hence, landsliding events are not directly controlled by weathering of bedrock. About 31% of landslides identified in this study deposited material in stream reaches, with about 83% of these landslides deposited in reaches with gradients between 3% and 10%.

New evidence for the age of the Skonun Formation, Queen Charlotte Islands, British Columbia

1981 ◽  
Vol 18 (12) ◽  
pp. 1900-1903 ◽  
Author(s):  
N. Champigny ◽  
C. M. Henderson ◽  
G. E. Rouse
Keyword(s):  
British Columbia ◽  
Pacific Northwest ◽  
Middle Miocene ◽  
Early Miocene ◽  
Queen Charlotte Islands ◽  
The Pacific ◽  
New Evidence

Recent palynological, megafaunal, and intrusive evidence from a section low in the Skonun Formation in the Cinola deposit on Graham Island indicates that it was deposited in the late Early Miocene, and that the age of the Skonun ranges up to the early Middle Miocene in outcrop sections on northeastern Graham Island. Correlations are made with several Miocene series of the Pacific Northwest and Alaska.

The lichens and lichenicolous fungi of Haida Gwaii (Queen Charlotte Islands), British Columbia, Canada. 5. A new species of Lecanora from shoreline rocksThis paper is one of a selection of papers published as part of the special Schofield Gedenkschrift.

Botany ◽  
2010 ◽  
Vol 88 (4) ◽  
pp. 352-358 ◽  
Author(s):  
Irwin M. Brodo
Keyword(s):  
British Columbia ◽  
New Species ◽  
Pacific Northwest ◽  
Similar Species ◽  
Haida Gwaii ◽  
Queen Charlotte Islands ◽  
The Pacific ◽  
A New Species ◽  
Selection Of ◽  
Northeast Coast

A species of Lecanora in the L. dispersa group, with a well-developed pale thallus and a granular epihymenium, resembling L. albescens , is found exclusively on shoreline rocks and appears to be new. It is described as Lecanora schofieldii  sp. nov., found mainly in the Pacific Northwest, but also rarely on the northeast coast. Its distinctions from similar species on shoreline rocks are given, together with a key for their identification. The first western record of L. xylophila from rocks is given.

Experiments on Oral Secretion of the Rocky Mountain Wood Tick, Dermacentor andersoni Stiles (Acarina: Ixodidae)

1957 ◽  
Vol 89 (1) ◽  
pp. 1-5 ◽  
Author(s):  
J. D. Gregson
Keyword(s):  
British Columbia ◽  
Pacific Northwest ◽  
Rocky Mountain ◽  
Dermacentor Variabilis ◽  
Oral Secretion ◽  
Amblyomma Maculatum ◽  
Dermacentor Andersoni ◽  
The Pacific ◽  
Tick Paralysis ◽  
Rocky Mountain Wood Tick

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.

1999 Pacific Northwest Labor History Association Conference

2000 ◽  
Vol 57 ◽  
pp. 117-119 ◽  
Author(s):  
Daniel Jacoby
Keyword(s):  
British Columbia ◽  
Pacific Northwest ◽  
Labor History ◽  
Definitive Answer ◽  
Preferable Alternative ◽  
The Pacific ◽  
The Moment ◽  
Academic Conferences

I cannot provide a definitive answer to those of us pondering what the best alternative to capitalism is, but after attending the Pacific Northwest Labor History Association (PNLHA) Conference in Westminster, British Columbia, over the weekend of May 28–30, 1999, I can tell you that this is certainly a preferable alternative to standard academic conferences. As usual, the PNLHA was able to produce a cadre of historians (from the trades as well as academia), active unionists, and old-timers whose memories are as tapable as a keg of beer. Although the association designates labor history as its subject, newly elected President Ross Rieder likes to say, “History ends the moment before now.”

Canopy disturbances over the five-century lifetime of an old-growth Douglas-fir stand in the Pacific Northwest

2002 ◽  
Vol 32 (6) ◽  
pp. 1057-1070 ◽  
Author(s):  
Linda E Winter ◽  
Linda B Brubaker ◽  
Jerry F Franklin ◽  
Eric A Miller ◽  
Donald Q DeWitt
Keyword(s):  
Pacific Northwest ◽  
Variable Density ◽  
Tsuga Heterophylla ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Old Growth ◽  
The Pacific ◽  
History Of ◽  
Horizontal Heterogeneity ◽  
Restoration Strategies

The history of canopy disturbances over the lifetime of an old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand in the western Cascade Range of southern Washington was reconstructed using tree-ring records of cross-dated samples from a 3.3-ha mapped plot. The reconstruction detected pulses in which many western hemlock (Tsuga heterophylla (Raf.) Sarg.) synchronously experienced abrupt and sustained increases in ringwidth, i.e., "growth-increases", and focused on medium-sized or larger ([Formula: see text]0.8 ha) events. The results show that the stand experienced at least three canopy disturbances that each thinned, but did not clear, the canopy over areas [Formula: see text]0.8 ha, occurring approximately in the late 1500s, the 1760s, and the 1930s. None of these promoted regeneration of the shade-intolerant Douglas-fir, all of which established 1500–1521. The disturbances may have promoted regeneration of western hemlock, but their strongest effect on tree dynamics was to elicit western hemlock growth-increases. Canopy disturbances are known to create patchiness, or horizontal heterogeneity, an important characteristic of old-growth forests. This reconstructed history provides one model for restoration strategies to create horizontal heterogeneity in young Douglas-fir stands, for example, by suggesting sizes of areas to thin in variable-density thinnings.

Notes on Parathion-Resistant Strains of Two Phytophagous Mites and a Predacious Mite in British Columbia

1958 ◽  
Vol 90 (2) ◽  
pp. 92-97 ◽  
Author(s):  
C. V. G. Morgan ◽  
N. H. Anderson
Keyword(s):  
British Columbia ◽  
Pacific Northwest ◽  
Predacious Mites ◽  
Predacious Mite ◽  
Phytophagous Mites ◽  
European Red Mite ◽  
The Pacific ◽  
Resistant Strains ◽  
Tetranychus Pacificus

The existence of strains of mites resistant to parathion has been well established (Garman, 1950; Lienk, Dean, & Chapman, 1952; Newcomer & Dean, 1952; Smith & Fulton, 1951). Resistant strains of the European red mite, Metatetranychus ulmi (Koch), first occurred in orchards of the Pacific northwest in 1950 (Newcomer, 1951; O'Neill & Hantsbarger, 1951), approximately three years after parathion was first used as an acaricide. Two other species of orchard mites, the Pacific mite, Tetranychus pacificus McG., and T. mcdanieli McG., were subsequently reported to have developed parathion-resistant strains in the same area (Newcomer & Dean, 1953). Though parathion is lethal to most predacious mites and insects, Huffaker and Kennett (1953) found a difference in tolerance between species of Typhlodromus in the field and in the laboratory: T. reticulatus Oudms. was very susceptible to parathion whereas T. occidentalis Nesbitt was not appreciably affected by it.

Comparing productivity of pure and mixed Douglas-fir and western hemlock plantations in the Pacific Northwest

2006 ◽  
Vol 36 (6) ◽  
pp. 1484-1496 ◽  
Author(s):  
M M Amoroso ◽  
E C Turnblom
Keyword(s):  
Pacific Northwest ◽  
Stand Density ◽  
Tsuga Heterophylla ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Mixed Stand ◽  
Mixed Stands ◽  
Individual Tree ◽  
The Pacific ◽  
Increase In Productivity

We studied pure and 50/50 mixtures of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) plantations to compare attained total yields between mixed-species stands as opposed to monocultures of equal densities. Whether overall stand density influences this outcome has not been adequately investigated, and to address this we included three density levels (494, 1111, and 1729 trees/ha) in the analysis. At age 12, as components of the mixed stands, Douglas-fir exhibited greater height, diameter, and individual-tree volume than western hemlock at all densities. At 494 and 1111 trees/ha the monocultures had a higher volume per hectare than the mixed stand, but at 1729 trees/ha the mixed stand appeared to be just as productive as the pure stands. The increase in productivity by the mixture at high densities seems to have resulted from the partial stratification observed and most likely also from better use of the site resources. Because of this, less interspecific competition was probably experienced in the mixed stand than intraspecific competition in the pure stands. This study shows the important role density plays in the productivity of mixed stands and thus in comparing mixed and pure stands.

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