The applicability of available hazard rating systems for mountain pine beetle in lodgepole pine stands of southeastern Wyoming

1986 ◽  
Vol 16 (2) ◽  
pp. 222-225 ◽  
Author(s):  
Steven A. Katovich ◽  
Robert J. Lavigne
Keyword(s):  
Mountain Pine Beetle ◽  
The United States ◽  
Rating Systems ◽  
Growth Ratio ◽  
Diameter At Breast Height ◽  
Medicine Bow Mountains ◽  
Breast Height ◽  
Periodic Growth ◽  
Hazard Rating ◽  
Hazard Rating Systems

Five hazard rating systems for Dendroctonusponderosae Hopkins in Pinuscontorta Dougl. stands were compared under nonoutbreak conditions in the Medicine Bow Mountains of southeastern Wyoming. The applicability of these systems, which were designed in other regions of the United States, to P. contorta stands in southeastern Wyoming was investigated. Thirty-two stands in four different age and diameter categories were sampled and rated by each system. Diameter at breast height did not correlate well with phloem width in any of the stands, as implied by the system of Amman and co-workers. A direct phloem width measurement could further refine this system. Periodic growth ratio, used in both the Berryman and Mahoney systems, did not differentiate between fast- and slow-growing trees. Crown competition factor did not positively correlate with increasing diameter at breast height, as implied by the system of Schenk and co-workers. Stand production ranged from 11.1 to 51.0 g wood•m leaf area−2•year−1, applying a modified system based on that designed by Mitchell and co-workers, indicating very high risk in every stand sampled. Further development and validation of hazard rating systems is necessary for improved analysis of risk to P. contorta stands from D. ponderosae in this region.

Hazard rating of lodgepole pine stands to mountain pine beetle outbreaks in southcentral Oregon

1984 ◽  
Vol 14 (5) ◽  
pp. 666-671 ◽  
Author(s):  
John David Stuart
Keyword(s):  
Mountain Pine Beetle ◽  
Stand Structure ◽  
Stand Density ◽  
Stepwise Discriminant Analysis ◽  
Growth Ratio ◽  
South Central ◽  
Periodic Growth ◽  
Quadratic Mean Diameter ◽  
Stand Density Index ◽  
Hazard Rating

Stand structure and vigor variables were used to develop a model for predicting the development of a Dendroctonusponderosae Hopk. outbreak in climax Pinuscontorta Dougl. ex Loud. var. murrayana Grev. and Balf. stands in south central Oregon. Stepwise discriminant analysis indicated the significant predictor variables were quadratic mean diameter and the number of rings in the outermost centimetre of radial growth at breast height (p = 0.00001, canonical correlation coefficient = 0.77235). Ninety-three percent of the stands were correctly classified into their appropriate groups (attacked versus unattacked). None of the five indices of competition tested (i) Waring and Pitman's tree vigor index, (ii) Mahoney's periodic growth ratio, (iii) Krajicek's crown competition factor, (iv) Hegyi's competition index, and (v) Curtis's stand density index) were significant discriminators.

DEVELOPING AND SELECTING SLOPE STABILIZATION TECHNIQUES IN MANAGING SLOPE FAILURES

2016 ◽  
Vol 12 (4) ◽  
Author(s):  
Ari Sandyavitri
Keyword(s):  
Retaining Wall ◽  
Value Engineering ◽  
Rating Systems ◽  
Slope Stabilization ◽  
Rockfall Hazard ◽  
Proactive Approach ◽  
West Sumatra ◽  
Hazard Rating ◽  
Hazard Rating Systems ◽  
Steep Slopes

This paper objectives are to; (i) identification of risky slopes (within 4 Provinces in Sumatra including Provinces of Riau, West Sumatra, Jambi and South Sumatra encompassing 840 kms of the “Jalan Lintas Sumatra” highway) based on Rockfall Hazard Rating Systems (RHRS) method; (ii) developing alternatives to stabilize slope hazards, and (iii) selecting appropriate slopes stabilization techniques based on both proactive approach and value engineering one. Based on the Rockfall Hazard Rating Systems (RHRS) method, it was identified 109 steep slopes prone to failure within this highway section. Approximately, 15 slopes were identified as potential high-risk slopes (RHRS scores were calculated >200 points). Based on the proactive approach, seven riskiest slopes ware identified. The preferred stabilization alternatives to remedy most of these slopes are suggested as follow; either (i) a combination of retaining wall and drainage, or (ii) gabion structure and drainage. However, different approaches may yield different results, there are at least 2 main consideration in prioritizing slope stabilization; (i) based on the riskiest slopes, and(ii) the least expensive stabilization alternatives.

scholarly journals Rockfall Hazard Rating System(s) in Saudi Arabia – A Review

2018 ◽  
Vol 10 (4) ◽  
pp. 1 ◽  
Author(s):  
Adnan M. Aqeel
Keyword(s):  
Saudi Arabia ◽  
Specific Area ◽  
Economic Loss ◽  
Slope Instability ◽  
Rating System ◽  
Rating Systems ◽  
Rockfall Hazard ◽  
Risk Definition ◽  
Hazard Rating ◽  
Hazard Rating Systems

Slope instability along highways in mountainous areas is not only a major hazard for lives and passing vehicles but also may hinder traffic for long period and thus create significant economic loss. The most common type of slope instability failures in such areas is rockfalls. Many qualitative rockfall hazard rating systems (RHRSs) have been developed across the world. However, the Middle East almost lacks to such systems. For instance, in Saudi Arabia, which has the largest economy in the region, only one system of rockfall hazard rating system (RHRS-SA) has been developed up to now. This paper aimed to critically review this system. Some drawbacks were found in the RHRS-SA. However, the main disadvantage was that the final rating score of risk is not consistent with risk definition. In sum, the remarkable findings of this review can be accounted either for any future modifications for the RHRS-SA or to develop a new rockfall hazard rating system but for a specific area(s) in Saudi Arabia.

A simplified tree bait for the mountain pine beetle

1993 ◽  
Vol 23 (6) ◽  
pp. 1108-1113 ◽  
Author(s):  
J.H. Borden ◽  
L.J. Chong ◽  
B.S. Lindgren ◽  
E.J. Begin ◽  
T.M. Ebata ◽  
...  
Keyword(s):  
Release Rate ◽  
Mountain Pine Beetle ◽  
Diameter Class ◽  
Individual Tree ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Mountain Pine ◽  
Pine Beetle ◽  
Antiaggregation Pheromone ◽  
And Control

Seven, split-block experiments throughout British Columbia in 1989 tested the efficacy of binary tree baits containing the pheromones trans-verbenol and exo-brevicomin or ternary baits with the addition of the host tree kairomone myrcene for containing and concentrating infestations of the mountain pine beetle, Dendroctonusponderosae Hopkins, in stands of lodgepole pine, Pinuscontorta var. latifolia Engelm. Attack densities on baited trees, attack frequencies of baited trees and trees within 10 m of the baited trees, and the ratios of newly attacked, green, trees to previously attacked, red, trees were generally statistically equal between sub-blocks containing binary or ternary baits. Where statistically significant differences occurred for one or more of the above criteria in one experiment, they were generally offset by statistically significant differences in the opposite direction in another experiment. Two individual-tree experiments in 1990 that supported the equality of binary and ternary baits indicated that raising the release rate of trans-verbenol in binary baits tended to reduce their efficacy (possibly because of contamination with the antiaggregation pheromone verbenone) and showed that increasing the release rate of exo-brevicomin tended to counteract this effect. When attack frequencies were subdivided by diameter class of available trees attacked, all baits were effective in inducing attack on available trees <30.0 cm diameter at breast height (1.3 m), but attack on baited and control trees ≥30 cm diameter at breast height was equal. Provided that the trans-verbenol in binary baits does not contain or autoxidize to verbenone, myrcene can be deleted from operational tree baits.

Growth characteristics of lodgepole pine associated with the start of mountain pine beetle outbreaks

1983 ◽  
Vol 13 (1) ◽  
pp. 137-144 ◽  
Author(s):  
D. M. Shrimpton ◽  
A. J. Thomson
Keyword(s):  
Tree Growth ◽  
Mountain Pine Beetle ◽  
Cost Effective ◽  
Annual Increment ◽  
Growth Ratio ◽  
Stand Growth ◽  
Mountain Pine ◽  
Periodic Growth ◽  
Pine Beetle ◽  
Mean Annual Increment

The dynamics of tree and stand growth were studied in six small but expanding mountain pine beetle outbreaks in British Columbia. Stands had exceeded a previously reported hazard threshold of age 80 years by 26 years, and a second frequently used hazard threshold of 20.5 cm mean dbh was exceeded by 37 years. However, stands had exceeded maturity, as defined by the intersection of current annual increment (CAI) and mean annual increment (MAI), by an average of only 17 years. In all cases, the beginnings of the outbreaks were coincident with a period of reduced tree growth. This reduced tree growth was difficult to detect at breast height, with a consequent failure of the periodic growth ratio to indicate susceptibility. Although the stands were past the point of maturity, the dominant and codominant trees continued to add significant wood volume, which could make surveillance for incipient outbreaks and subsequent control actions cost effective.

Understanding windthrow: Silvicultural implications

1995 ◽  
Vol 71 (4) ◽  
pp. 434-445 ◽  
Author(s):  
Jean-Claude Ruel
Keyword(s):  
Stand Density ◽  
Rating Systems ◽  
Root Characteristics ◽  
Stem Form ◽  
Related Factors ◽  
Canadian Context ◽  
Anchoring System ◽  
Hazard Rating ◽  
Hazard Rating Systems ◽  
The Impact

Windthrow is a damaging agent that can be of paramount importance in silviculture. Windthrow depends on a number of factors interacting with each other. This paper tries to incorporate windthrow concerns into the silvicultural decision making process by understanding the windthrow process and its interaction with silviculture. The forces involved in the windthrow process are reviewed. The effects of natural factors on these forces are examined and the potential impact of silviculture on these factors is discussed. Some available hazard rating systems are reviewed, trying to underline their applicability in the Eastern Canadian context. Climate affects the severity and frequency of storms. However, wind speed in a particular stand is influenced strongly by local topography. Soil and root characteristics determine the sturdiness of the anchoring system. Many stand-related factors, such as stand height, age, density and stem form, can also exert an influence on the resistance to uprooting. Silviculture can modify the vulnerability to windthrow by acting on these factors. In stands at risk, stripcutting, thinning or the creation of new margins can cause important losses. The impact of stem form also indicates the need for an early control of stand density. Among the hazard rating systems available, the British system seems the most complete but would require some adjustments for use in the Eastern Canadian context. Key words: windthrow, uprooting, blowdown, wind

Solvent safety I: Hazard rating systems

2003 ◽  
Vol 101 (6) ◽  
pp. 126-129
Author(s):  
John B. Durkee
Keyword(s):  
Rating Systems ◽  
Hazard Rating ◽  
Hazard Rating Systems
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