Regeneration and growth of lodgepole pine in small openings in the Alberta Foothills

1987 ◽  
Vol 17 (7) ◽  
pp. 758-759 ◽  
Author(s):  
P. Y. Bernier
Keyword(s):  
Lodgepole Pine ◽  
Clear Cut ◽  
East West

A survey carried out in 13-year-old circular openings of 1, 2, 4, and 6 tree heights (H) in diameter, in a 1H east–west strip, and in a 20-ha clear-cut of similar ages shows that regeneration of lodgepole pine (Pinuscontorta Dougl. var. latifolia Engelm.) in the 4H and 6H cuts is comparable with that of the larger clear-cut. Regeneration is poor in the 2H opening and nonexistent in the 1H circular openings. The 1H east–west strip shows good regeneration.

Susceptibility of lodgepole pine provenances to geographically separate western gall rust spore sources

1988 ◽  
Vol 18 (9) ◽  
pp. 1203-1205 ◽  
Author(s):  
B. J. van der Kamp
Keyword(s):  
British Columbia ◽  
Factorial Design ◽  
Significant Interaction ◽  
Lodgepole Pine ◽  
East West

Seven lodgepole pine (Pinusconforta Dougl.) provenances collected along an east–west transect from the Cypress Hills, Saskatchewan, to Vancouver, British Columbia, were inoculated as 1-year-old seedlings with one coastal and three British Columbia interior western gall rust (Endocronartiumharknessii (J.P. Moore) Y. Hiratsuka) spore sources in a factorial design. Infection levels ranged from 4 to 95% (average 56.4%, based on 1032 inoculated seedlings). ANOVA of arc sine transformed percent seedlings infected demonstrated a significant interaction between provenance and spore source (P = 0.029). Provenance, spore source, and their interaction accounted for 70, 14, and 6% of the variation, respectively.

scholarly journals Variability in sub-regional impacts of dwarf mistletoe on mature lodgepole pine

1997 ◽  
Vol 73 (3) ◽  
pp. 371-375 ◽  
Author(s):  
Alan J. Thomson ◽  
John A. Muir ◽  
Kathy J. Lewis
Keyword(s):  
Forest Inventory ◽  
Lodgepole Pine ◽  
Stand Density ◽  
Dwarf Mistletoe ◽  
Clear Cut ◽  
Regional Impacts ◽  
Forest Practices ◽  
Roadside Survey ◽  
Pine Stands ◽  
Old Trees

Impact of lodgepole pine dwarf mistletoe was determined in six sub-areas of Forest Inventory Zone H, near Prince George, British Columbia, using a roadside survey and measurements of mature infected trees. Mistletoe effects on DBH were evident only in two of the sub-areas surveyed (Westlake and Nechako). After correcting DBH measurements for competition (stand density), dbh of 100–120 year old and 121–150 year old trees was reduced 10% and 17% respectively, in the highest mistletoe rating (DMR) category (4.5–6.0). Height/DBH relationships were affected by dwarf mistletoe only in the Nechako area. Mistletoe effects in the Nechako and Westlake areas, in stands older than 120 years with mistletoe ratings of 4.5–6.0, resulted in volume reductions of 28–42%, depending on the effects of mistletoe on height. Further losses might accrue in lodgepole pine stands if clear-cut harvesting were restricted by the BC Forest Practices Code, unless infected stems are selectively removed. Key words: roadside survey, dwarf mistletoe rating (DMR), Forest Practices Code

A comparison of mature with recently clear-cut and scarified lodgepole pine forests in the Lower Foothills of Alberta

1976 ◽  
Vol 6 (1) ◽  
pp. 20-32 ◽  
Author(s):  
Ian G. W. Corns ◽  
George H. La Roi
Keyword(s):  
Vascular Plants ◽  
Lodgepole Pine ◽  
Tree Regeneration ◽  
Dwarf Shrub ◽  
Shrub Cover ◽  
Above Ground Biomass ◽  
Clear Cut ◽  
Clear Cutting ◽  
Feather Moss ◽  
Gravimetric Sampling

Mature, even-aged lodgepole pine (Pinuscontorta Dougl. var latifolia Engelm.) forests on upland sites with Orthic Gray Luvisols in the Lower Foothills of Alberta have been clear-cut for pulpwood and scarified by bulldozer since 1958. Undisturbed stands had weak shrub strata, well developed herb – dwarf shrub strata, and continuous feather moss strata.In 25 clear-cut stands 6–12 years old, the average cover of vascular plants was 54% and did not change significantly during the sampled age interval. Cover of tree 'regeneration' (immature size classes) was 5%, increasing slowly, and codominated by lodgepole pine and aspen (Populustremuloides Michx.). Shrub cover was also 5% and dominated by prickly rose (Rosaacicularis Lindl.). Herb – dwarf shrub cover was 44% and dominated by nine species of the mature forest. Bryoid cover was 13 %.The density of young trees stabilized within 6 years after clear-cutting, and the above-ground biomass of both pine and aspen increased rapidly during the sampled age interval.An ordination of the clear-cut stands showed that the distribution and abundance of several important plant species were well correlated with soil moisture on two gravimetric sampling dates in summer.A comparison of dominance–diversity curves and indices for mature and clear-cut stands revealed that the clear-cut community was richer in vascular species (100 cf. 57) and had a more even distribution of cover among species.The early stages of secondary succession after clear-cutting and scarification of lodgepole pine forest are discussed.

Black-stain root disease on lodgepole pine in British Columbia

1986 ◽  
Vol 16 (5) ◽  
pp. 996-999 ◽  
Author(s):  
R. S. Hunt ◽  
D. J. Morrison
Keyword(s):  
British Columbia ◽  
Lodgepole Pine ◽  
Root Disease ◽  
Risk Of Infection ◽  
Severe Damage ◽  
The West ◽  
Clear Cut

Surveys were made for incidence and damage by black-stain root disease (Ceratocystiswageneri) on Pinuscontorta in British Columbia. Incidence surveys indicated the hard pine pathotype to be largely restricted to the west Kootenays, northern Okanagan, and southern Cariboo. Damage surveys of 177 ha in 12 stands revealed severe damage in pure, dense stands, 80 years and older, at elevations above 1000 m. In one-half of the stands, C. wageneri was associated with Armillariaobscura; in one-third, some trees in C. wageneri centres were currently infested with Dendroctonusponderosae. Most disease centres were small, but sometimes there were many per stand, so that up to 46% of a stand was affected. The pattern of disease centres suggested that unknown vectors were responsible for initiating disease centres. Isolations from excavated stumps indicated little survival of C. wageneri after 1 year and none after2 years. Infested stands can be clear-cut and regenerated to P. contorta without risk of infection from the previous stand.

Random amplified polymorphic DNA variability among geographic isolates of western gall rust fungus in Canada

2001 ◽  
Vol 31 (8) ◽  
pp. 1304-1311 ◽  
Author(s):  
Changxi Li ◽  
Francis C Yeh ◽  
Yasu Hiratsuka
Keyword(s):  
Pinus Banksiana ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Random Amplified Polymorphic Dna ◽  
Rust Fungus ◽  
Jack Pine ◽  
Fungal Isolates ◽  
Rapd Pattern ◽  
Endocronartium Harknessii ◽  
East West

Geographic variability among western gall rust (WGR) fungus (Endocronartium harknessii (J.P. Moore) Y. Hiratsuka) was studied by random amplified polymorphic DNA (RAPD). Samples were taken from lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) host at four locations in British Columbia and Alberta and from jack pine (Pinus banksiana Lamb.) host at nine locations in Alberta, Saskatchewan, Manitoba, and Ontario. Of 90 random oligonucleotide primers screened, 9 were chosen for analysis. These nine primers consistently amplified 41 sharp and reproducible RAPDs (fragments) of the WGR fungal isolates over several independent runs. Eighteen of the 41 RAPDs were polymorphic (showing the presence of both marker and null phenotypes), of which 15 could discriminate WGR isolates of lodgepole pine hosts from jack pine ones. Of these 15 RAPDs, five were unique to isolates of lodgepole and five to jack pine. The remaining five RAPDs were significantly heterogeneous in the RAPD frequency between WGR isolates of the two host origins. The RAPD pattern of WGR isolates from lodgepole pine was uniform. However, isolates from jack pine differed significantly in the frequency of four RAPDs among locations, with an east-west trend of decreasing similarity in RAPD. Analysis of molecular variance apportioned 76.3, 14.4, and 9.3% of the total RAPD variability to differences among hosts, to differences among locations within hosts, and to differences within locations, respectively. The large differentiation between WGR fungal isolates sampled in lodgepole pine and jack pine hosts might suggest that selective pressure for host specificity in sampled populations was strong.

Shoulder Pain at Work: Causation Analysis

2017 ◽  
Vol 22 (1) ◽  
pp. 11-16
Author(s):  
Joel Weddington ◽  
Charles N. Brooks ◽  
Mark Melhorn ◽  
Christopher R. Brigham
Keyword(s):  
Epidemiological Data ◽  
Case Law ◽  
Individual Case ◽  
Shoulder Injury ◽  
Work Related ◽  
Clear Cut ◽  
The Individual ◽  
Causation Analysis ◽  
Injury Causation ◽  
Relevant Factors

Abstract In most cases of shoulder injury at work, causation analysis is not clear-cut and requires detailed, thoughtful, and time-consuming causation analysis; traditionally, physicians have approached this in a cursory manner, often presenting their findings as an opinion. An established method of causation analysis using six steps is outlined in the American College of Occupational and Environmental Medicine Guidelines and in the AMA Guides to the Evaluation of Disease and Injury Causation, Second Edition, as follows: 1) collect evidence of disease; 2) collect epidemiological data; 3) collect evidence of exposure; 4) collect other relevant factors; 5) evaluate the validity of the evidence; and 6) write a report with evaluation and conclusions. Evaluators also should recognize that thresholds for causation vary by state and are based on specific statutes or case law. Three cases illustrate evidence-based causation analysis using the six steps and illustrate how examiners can form well-founded opinions about whether a given condition is work related, nonoccupational, or some combination of these. An evaluator's causal conclusions should be rational, should be consistent with the facts of the individual case and medical literature, and should cite pertinent references. The opinion should be stated “to a reasonable degree of medical probability,” on a “more-probable-than-not” basis, or using a suitable phrase that meets the legal threshold in the applicable jurisdiction.

Values and intergroup perceptions of East Germans and West Germans in 1998 1This research was supported by a grant from the German Research Society (We 1106/3-1).

1999 ◽  
Vol 58 (4) ◽  
pp. 263-272
Author(s):  
Jörg Doll ◽  
Michael Dick
Keyword(s):  
Research Society ◽  
Frame Of Reference ◽  
Control Group ◽  
Perceived Similarity ◽  
The West ◽  
Need For Uniqueness ◽  
German Research ◽  
East German ◽  
Experimental Group ◽  
East West

The studies reported here focus on similarities and dissimilarities between the terminal value hierarchies ( Rokeach, 1973 ) ascribed to different groups ( Schwartz & Struch, 1990 ). In Study 1, n = 65 East Germans and n = 110 West Germans mutually assess the respective ingroup and outgroup. In this intra-German comparison the West Germans, with a mean intraindividual correlation of rho = 0.609, perceive a significantly greater East-West similarity between the group-related value hierarchies than the East Germans, with a mean rho = 0.400. Study 2 gives East German subjects either a Swiss (n = 58) or Polish (n = 59) frame of reference in the comparison between the categories German and East German. Whereas the Swiss frame of reference should arouse a need for uniqueness, the Polish frame of reference should arouse a need for similarity. In accordance with expectations, the Swiss frame of reference significantly reduces the correlative similarity between German and East German from a mean rho = 0.703 in a control group (n = 59) to a mean rho = 0.518 in the experimental group. Contrary to expectations, the Polish frame of reference does not lead to an increase in perceived similarity (mean rho = 0.712).

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