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Barbara J. Bentz - One of the best experts on this subject based on the ideXlab platform.
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Modeling Mountain Pine Beetle (Dendroctonus ponderosae) oviposition
Entomologia Experimentalis Et Applicata, 2019Co-Authors: Anne E. Mcmanis, James A. Powell, Barbara J. BentzAbstract:Mountain Pine Beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is a significant forest disturbance agent with a widespread distribution in western North America. Population success is influenced by temperatures that drive phenology and ultimately the adult emergence synchrony required to mass attack and kill host trees during outbreaks. In addition to lifestage‐specific developmental rates and thresholds, oviposition timing can be a source of variance in adult emergence synchrony, and is a critical aspect of Mountain Pine Beetle phenology. Adaptation to local climates has resulted in longer generation times in southern compared to northern populations in common gardens, and the role of oviposition rate in these differences is unclear. Oviposition rates and fecundity in a northern population have been described, although data are lacking for southern populations. We assessed southern Mountain Pine Beetle oviposition rates and fecundity in a range of temperatures using a non‐destructive technique that included frequent X‐ray imaging. We found that oviposition rate and fecundity vary independently such that a female with high oviposition rate did not necessarily have high fecundity and vice versa. Observed fecundity within the 30‐day experimental period was lowest at the lowest temperature, although estimated potential fecundity did not differ among temperatures. Females at varying temperatures have the potential to lay similar numbers of eggs, although it will take longer at lower temperatures. Southern Mountain Pine Beetle reared in Pinus strobiformis Engelm. (Pinaceae) had a higher upper threshold for oviposition, a similar lower threshold, and slightly greater potential fecundity compared to a northern population reared in Pinus contorta Douglas. A comparison of modeled oviposition rates between the two populations, which could be influenced by host tree, suggests that differences in oviposition rate do not explain observed differences in total generation time. Our oviposition model will facilitate development of a phenology model for southern Mountain Pine Beetle populations.
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Low offspring survival in Mountain Pine Beetle infesting the resistant Great Basin bristlecone Pine supports the preference-performance hypothesis
PLOS ONE, 2018Co-Authors: Erika L. Eidson, Karen E. Mock, Barbara J. BentzAbstract:The preference-performance hypothesis states that ovipositing phytophagous insects will select host plants that are well-suited for their offspring and avoid host plants that do not support offspring performance (survival, development and fitness). The Mountain Pine Beetle (Dendroctonus ponderosae), a native insect herbivore in western North America, can successfully attack and reproduce in most species of Pinus throughout its native range. However, Mountain Pine Beetles avoid attacking Great Basin bristlecone Pine (Pinus longaeva), despite recent climate-driven increases in Mountain Pine Beetle populations at the high elevations where Great Basin bristlecone Pine grows. Low preference for a potential host plant species may not persist if the plant supports favorable insect offspring performance, and Great Basin bristlecone Pine suitability for Mountain Pine Beetle offspring performance is unclear. We infested cut bolts of Great Basin bristlecone Pine and two susceptible host tree species, limber (P. flexilis) and lodgepole (P. contorta) Pines with adult Mountain Pine Beetles and compared offspring performance. To investigate the potential for variation in offspring performance among Mountain Pine Beetles from different areas, we tested Beetles from geographically-separated populations within and outside the current range of Great Basin bristlecone Pine. Although Mountain Pine Beetles constructed galleries and laid viable eggs in all three tree species, extremely few offspring emerged from Great Basin bristlecone Pine, regardless of the Beetle population. Our observed low offspring performance in Great Basin bristlecone Pine corresponds with previously documented low Mountain Pine Beetle attack preference. A low preference-low performance relationship suggests that Great Basin bristlecone Pine resistance to Mountain Pine Beetle is likely to be retained through climate-driven high-elevation Mountain Pine Beetle outbreaks.
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Mountain Pine Beetle host selection behavior confirms high resistance in Great Basin bristlecone Pine
Forest Ecology and Management, 2017Co-Authors: Erika L. Eidson, Karen E. Mock, Barbara J. BentzAbstract:Abstract Over the last two decades, Mountain Pine Beetle ( Dendroctonus ponderosae ) populations reached epidemic levels across much of western North America, including high elevations where cool temperatures previously limited Mountain Pine Beetle persistence. Many high-elevation Pine species are susceptible hosts and experienced high levels of mortality in recent outbreaks, but co-occurring Great Basin bristlecone Pines ( Pinus longaeva ) were not attacked. Using no-choice attack box experiments, we compared Great Basin bristlecone Pine resistance to Mountain Pine Beetle with that of limber Pine ( P. flexilis ), a well-documented Mountain Pine Beetle host. We confined sets of Mountain Pine Beetles onto 36 pairs of living Great Basin bristlecone and limber Pines and recorded Beetle status after 48 h. To test the role of induced defenses in Great Basin bristlecone Pine resistance, we then repeated the tests on 20 paired sections of Great Basin bristlecone and limber Pines that had been recently cut, thereby removing their capacity for induced defensive reactions to an attack. In tests on cut trees, we also investigated the potential for population-level differences in Mountain Pine Beetle host selection behavior by testing Beetles from two separate geographic regions. Beetles placed on Great Basin bristlecone Pine rarely initiated attacks relative to those placed on limber Pine in both studies, regardless of the Beetle population source. Our results indicate that Great Basin bristlecone Pine has a high level of resistance to Mountain Pine Beetle due at least in part to stimuli that repel pioneering attackers from initiating attacks, even when induced defenses are compromised.
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Mountain Pine Beetle dynamics and reproductive success in post fire lodgepole and ponderosa Pine forests in northeastern utah
PLOS ONE, 2016Co-Authors: Andrew P Lerch, Barbara J. Bentz, Jesse A Pfammatter, Kenneth F. RaffaAbstract:Fire injury can increase tree susceptibility to some bark Beetles (Curculionidae, Scolytinae), but whether wildfires can trigger outbreaks of species such as Mountain Pine Beetle (Dendroctonus ponderosae Hopkins) is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug.) and 599 ponderosa (Pinus ponderosa Doug. ex Law) Pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic Mountain Pine Beetle. We examined how the degree and type of fire injury influenced Beetle attacks, brood production, and subsequent tree mortality, and related these to Beetle population changes over time. Mountain Pine Beetle population levels were high the first two post-fire years in lodgepole Pine, and then declined. In ponderosa Pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa Pines, but additional injury was more likely to decrease attack rates in lodgepole Pines. In lodgepole Pine, attacks were initially concentrated on fire-injured trees, but during subsequent years Beetles attacked substantial numbers of uninjured trees. In ponderosa Pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa Pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole Pine but increased in ponderosa Pine, however these relationships did not scale to whole trees. Mountain Pine Beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.
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Elevational shifts in thermal suitability for Mountain Pine Beetle population growth in a changing climate
Forestry, 2016Co-Authors: Barbara J. Bentz, Jacob P. Duncan, James A. PowellAbstract:Future forests are being shaped by changing climate and disturbances. Climate change is causing large-scale forest declines globally, in addition to distributional shifts of many tree species. Because environmental cues dictate insect seasonality and population success, climate change is also influencing tree-killing bark Beetles. The Mountain Pine Beetle, Dendroctonus ponderosae, is a major disturbance in Pinus forests of the western US. Using a mechanistic, phenology-based demographic model driven by downscaled daily temperature data, we describe recent and future spatial and temporal thermal suitability for Mountain Pine Beetle population growth in a topographically complex region. Trends in model-predicted growth rates among Global Climate Models were similar and suggest that, relative to future trends, Mountain Pine Beetle population growth within the past 60 years was most optimal at middle elevations and least optimal at the lowest and highest elevations. This trend aligns with observed Mountain Pine Beetle-caused tree mortality that was greatest at middle elevations between 1997 and 2013, as estimated from Aerial Detection Surveys. However, thermal suitability for optimal phenological synchrony was predicted to shift in recent years, and by the end of the century, the best thermal habitats for Mountain Pine Beetle will be at the lowest and highest elevations. Mechanistic demographic models are valuable tools for modelling future thermal regimes that may be both beneficial and maladaptive for Mountain Pine Beetle population growth and subsequent tree mortality.
J. A. Logan - One of the best experts on this subject based on the ideXlab platform.
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climate influences on whitebark Pine mortality from Mountain Pine Beetle in the greater yellowstone ecosystem
Ecological Applications, 2016Co-Authors: Polly C Buotte, Kenneth F. Raffa, Jeffrey A Hicke, Haiganoush K Preisler, John T Abatzoglou, J. A. LoganAbstract:Extensive mortality of whitebark Pine, beginning in the early to mid-2000s, occurred in the Greater Yellowstone Ecosystem (GYE) of the western USA, primarily from Mountain Pine Beetle but also from other threats such as white Pine blister rust. The climatic drivers of this recent mortality and the potential for future whitebark Pine mortality from Mountain Pine Beetle are not well understood, yet are important considerations in whether to list whitebark Pine as a threatened or endangered species. We sought to increase the understanding of climate influences on Mountain Pine Beetle outbreaks in whitebark Pine forests, which are less well understood than in lodgepole Pine, by quantifying climate–Beetle relationships, analyzing climate influences during the recent outbreak, and estimating the suitability of future climate for Beetle outbreaks. We developed a statistical model of the probability of whitebark Pine mortality in the GYE that included temperature effects on Beetle development and survival, precipitation effects on host tree condition, Beetle population size, and stand characteristics. Estimated probability of whitebark Pine mortality increased with higher winter minimum temperature, indicating greater Beetle winter survival; higher fall temperature, indicating synchronous Beetle emergence; lower two-year summer precipitation, indicating increased potential for host tree stress; increasing Beetle populations; stand age; and increasing percent composition of whitebark Pine within a stand. The recent outbreak occurred during a period of higher-than-normal regional winter temperatures, suitable fall temperatures, and low summer precipitation. In contrast to lodgepole Pine systems, area with mortality was linked to precipitation variability even at high Beetle populations. Projections from climate models indicate future climate conditions will likely provide favorable conditions for Beetle outbreaks within nearly all current whitebark Pine habitat in the GYE by the middle of this century. Therefore, when surviving and regenerating trees reach ages suitable for Beetle attack, there is strong potential for continued whitebark Pine mortality due to Mountain Pine Beetle.
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an innovative aerial assessment of greater yellowstone ecosystem Mountain Pine Beetle caused whitebark Pine mortality
Ecological Applications, 2013Co-Authors: William W Macfarlane, J. A. Logan, Wilson R KernAbstract:An innovative aerial survey method called the Landscape Assessment System (LAS) was used to assess Mountain Pine Beetle (MPB; Dendroctonus ponderosae)-caused mortality of whitebark Pine (Pinus albicaulis) across the species distribution in the Greater Yellowstone Ecosystem (GYE; 894 774 ha). This large-scale implementation of the LAS method consisted of 8673 km of flight lines, along which 4653 geo-tagged, oblique aerial photos were captured at the catchment level (a subset of 12-digit USGS hydrologic units) and geographic information system (GIS) processed. The Mountain Pine Beetle-caused Mortality Rating System, a landscape-scale classification system designed specifically to measure the cumulative effects of recent and older MPB attacks on whitebark Pine, was used to classify mortality with a rating from 0 to 6 based on the amount of red (recent attack) and gray (old attack) trees visible. The approach achieved a photo inventory of 79% of the GYE whitebark Pine distribution. For the remaining 21%, mort...
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Mountain Pine Beetle in high-elevation five-needle white Pine ecosystems
2011Co-Authors: Barbara J. Bentz, Kenneth E. Gibson, Sandy Kegley, Elizabeth M. Campbell, J. A. LoganAbstract:Across western North America Mountain Pine Beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae, Scolytinae), populations are growing at exponential rates in Pine ecosystems that span a wide range of elevations. As temperature increased over the past several decades, the flexible, thermally-regulated life-history strategies of Mountain Pine Beetle have allowed for increased population success in numerous habitats. Of particular concern are the high-elevation five-needle white Pines that are currently being infested. In a recent study of high-elevation whitebark Pine forests, Mountain Pine Beetles from multiple generations were found killing Pines within a single summer. These generations included parent Beetles that overwintered and emerged to attack new host trees, adult Beetles that developed in a single year (univoltine), and adult Beetles that required two years for life-cycle completion (semivoltine).
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Plant Disturbance Ecology - 16 – Dynamics of Mountain Pine Beetle Outbreaks
Plant Disturbance Ecology, 2007Co-Authors: J. Heavilin, James A. Powell, J. A. LoganAbstract:Insect disturbance, as suggested in this chapter, is important in maintaining a diverse age structure for lodgepole Pine. Left to its own devices, lodgepole would develop into crowded and unhealthy forests of over-mature trees. Although the Mountain Pine Beetle is an aggressive tree killer, it is a native component of natural ecosystems. The forests of the American West have coevolved in ways that incorporate Mountain Pine Beetle disturbance in the natural cycle of forest growth and regeneration. With disturbances such as Mountain Pine Beetles, a certain homeostasis can be maintained, at least on sufficiently large spatial scales. As the model in this chapter illustrates, insect disturbances can move at a self-limiting pace, balancing the rate of forest regeneration. Like fire (with which Mountain Pine Beetle reforestation is associated), Mountain Pine Beetle disturbance must be viewed as a normal and healthy part of ecosystem function on a sufficiently large scale. This chapter helps establish on what scales, both in time and space, an insect disturbance such as that caused by Mountain Pine Beetles can be expected to serve as a useful and normative disturbance.
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Modeling Mountain Pine Beetle phenological response to temperature
2003Co-Authors: J. A. Logan, James A. PowellAbstract:Maintaining an adaptive seasonality, with life cycle events occurring at appropriate times of year and in synchrony with ephemeral resources, is a basic ecological requisite. For poikilothermic organisms, phenology is largely determined through adaptive evolution with the prevailing climate, and in particular, annual temperature cycles. In addition to the direct effect of temperature, most temperate region insects have physiological mechanisms (e.g., diapause) that help to maintain an adaptive seasonality. The Mountain Pine Beetle (Dendroctonus ponderosae Hopkins), however, exhibits no obvious manifestations of diapause. This has led to the ecologically important question: How is an appropriate seasonality maintained in the Mountain Pine Beetle without the synchronizing infl uence of diapause? In answer to this basic question, we briefl y review the mathematical relationship between environmental temperatures and developmental timing and discuss the consequences of viewing these models as circle maps from the cycle of oviposition dates and temperatures of one year to oviposition dates for subsequent generations. Univoltinism, associated with reproductive success for the Mountain Pine Beetle, is related to stable fi xed points of the developmental circle map. Univoltine fi xed points are stable and robust in broad temperature bands, but lose stability suddenly to maladaptive cycles at the edges of these bands. This leads to the obvious observation that temperatures (weather) can be too cold for the Mountain Pine Beetle to thrive, as well as the less obvious implication that it can also be too warm. These results are placed in an ecological and management context by relating adaptive seasonality to outbreak potential. The relationship between outbreak potential and temperature is further considered in view of climate change (i.e., global warming). We briefl y note the potential for global warming to intensify outbreak characteristics in the current range of Mountain Pine Beetle, as well as promote invasion into new habitats, such as the high elevation Pines and northern range expansion into Canadian jack Pine. Mountain Pine Beetle Symposium: Challenges and Solutions. October 30-31, 2003, Kelowna, British Columbia. T.L. Shore, J.E. Brooks, and J.E. Stone (editors). Natural Resources Canada, Canadian Forest Service, Pacifi c Forestry Centre, Information Report BC-X-399, Victoria, BC. 298 p.
Allan L Carroll - One of the best experts on this subject based on the ideXlab platform.
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The Mountain Pine Beetle: causes and consequences of an unprecedented outbreak
2011Co-Authors: Allan L CarrollAbstract:The Mountain Pine Beetle (Dendroctonus ponderosae) is native to the Pine forests of western North America where it normally exists at very low densities, infesting only weakened or damaged trees. Under conditions conducive to survival, populations may erupt and spread over extensive landscapes, killing large numbers of healthy trees.
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Differences in the Constitutive Terpene Profile of Lodgepole Pine Across a Geographical Range in British Columbia, and Correlation with Historical Attack by Mountain Pine Beetle
Canadian Entomologist, 2010Co-Authors: Erin L. Clark, Allan L Carroll, Dezene P. W. HuberAbstract:Abstract The Mountain Pine Beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), is a destructive insect pest in western Nearctic conifer forests. Currently, British Columbia, Canada, is experiencing the largest recorded outbreak of this insect, including areas that historically have had low climatic suitability for it. We analyzed 26 constitutive resin terpenes in phloem samples from British Columbia lodgepole Pine (Pinus contorta) populations to test for differential resistance to Mountain Pine Beetle attack, based upon the likelihood of previous exposure to Mountain Pine Beetle. We assessed sampled trees for number of Mountain Pine Beetle attacks, number of pupal chambers, and tree survival the following spring. Significant differences were found when levels of certain terpenes in lodgepole Pine populations that had likely experienced substantial Mountain Pine Beetle infestations in the past were compared with those in populations that likely had not experienced large outbreaks of mounta...
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potential for range expansion of Mountain Pine Beetle into the boreal forest of north america
Canadian Entomologist, 2010Co-Authors: L. Safranyik, Barry J. Cooke, T. L. Shore, Allan L Carroll, Brian Peter, Jacques Regniere, David W Langor, W G Riel, V G Nealis, Stephen W TaylorAbstract:The potential for Mountain Pine Beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), to expand its historical range in North America from west of the continental divide into the eastern boreal forest was assessed on the basis of analyses of the effects of climate and weather on brood development and survival, and key aspects of the interaction of Mountain Pine Beetle with its hosts and associated organisms. Variation in climate suitability and high host susceptibility in the boreal forest create a finite risk of establishment and local persistence of low-level Mountain Pine Beetle populations outside their historical range. Eventually, these populations could become widespread and cause epidemic infestations, creating an ecological pathway eastward through the boreal forest. Such infestations would reduce the commercial value of forests and impose an additional disturbance on native ecological systems.
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Mountain Pine Beetle and forest carbon feedback to climate change
Nature, 2008Co-Authors: Werner A Kurz, Caren C. Dymond, Allan L Carroll, G Stinson, G J Rampley, E T Neilson, T Ebata, L. SafranyikAbstract:The forests of British Columbia are suffering a severe infestation with the Mountain Pine Beetle (Dendroctonus ponderosae). Climate change is thought to have contributed to the severity of this outbreak by allowing it to expand its range into formerly inhospitable areas. An analysis of the likely impact of the outbreak during the period 2000 to 2020 suggests that it will convert the forest from a small net carbon (C) sink to a large net C source. This change — and similar effects caused by other insect pests and forest fires — could put North American forest carbon sinks at risk, and should be taken into account when modelling the impact of climate change on carbon cycling. It is reported that the current severe outbreak of the Mountain Pine Beetle (Dendroctonus ponderosae) in British Columbia is likely to convert the forest from a small net carbon sink to a large net carbon source, something, it is argued, should be taken into account when modelling the impact of climate change on carbon cycling. The Mountain Pine Beetle (Dendroctonus ponderosae Hopkins, Coleoptera: Curculionidae, Scolytinae) is a native insect of the Pine forests of western North America, and its populations periodically erupt into large-scale outbreaks1,2,3. During outbreaks, the resulting widespread tree mortality reduces forest carbon uptake and increases future emissions from the decay of killed trees. The impacts of insects on forest carbon dynamics, however, are generally ignored in large-scale modelling analyses. The current outbreak in British Columbia, Canada, is an order of magnitude larger in area and severity than all previous recorded outbreaks4. Here we estimate that the cumulative impact of the Beetle outbreak in the affected region during 2000–2020 will be 270 megatonnes (Mt) carbon (or 36 g carbon m-2 yr-1 on average over 374,000 km2 of forest). This impact converted the forest from a small net carbon sink to a large net carbon source both during and immediately after the outbreak. In the worst year, the impacts resulting from the Beetle outbreak in British Columbia were equivalent to ∼75% of the average annual direct forest fire emissions from all of Canada during 1959–1999. The resulting reduction in net primary production was of similar magnitude to increases observed during the 1980s and 1990s as a result of global change5. Climate change has contributed to the unprecedented extent and severity of this outbreak6. Insect outbreaks such as this represent an important mechanism by which climate change may undermine the ability of northern forests to take up and store atmospheric carbon, and such impacts should be accounted for in large-scale modelling analyses.
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detecting Mountain Pine Beetle red attack damage with eo 1 hyperion moisture indices
Journal of remote sensing, 2007Co-Authors: Joanne C White, Michael A. Wulder, Nicholas C Coops, Thomas Hilker, Allan L CarrollAbstract:The Mountain Pine Beetle (Dendroctonus ponderosae) is the most destructive insect of mature Pine forests in western North America. Time series of wetness transformations generated from Landsat imagery have been used to detect Mountain Pine Beetle red attack damage over large areas. With the recent availability of high spatial (QuickBird) and high spectral (Hyperion) resolution satellite sensor imagery, the relationship between spectral moisture indices and levels of red attack damage may be investigated. Six moisture indices were generated from Hyperion data and were compared to the proportion of the Hyperion pixel having red attack damage. Results indicate the Hyperion moisture indices incorporating both the shortwave infrared (SWIR) and near infrared (NIR) regions of the electromagnetic spectrum concurrently, such as the Moisture Stress Index, were significantly correlated to levels of damage (r 2 = 0.51; p = 0.0001). The results corroborate the hypothesis that changes in foliage moisture resulting from Mountain Pine Beetle attack are driving the broad-scale temporal variation in Landsat derived wetness indices. Furthermore, the results suggest that Hyperion data may be used to map low levels of Mountain Pine Beetle red attack damage over large areas that are not consistently captured with Landsat data.
Michael A. Wulder - One of the best experts on this subject based on the ideXlab platform.
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Impact of Forest Fragmentation on Patterns of Mountain Pine Beetle-Caused Tree Mortality
Forests, 2013Co-Authors: Christopher Bone, Michael A. Wulder, Joanne C White, Colin Robertson, Trisalyn A NelsonAbstract:The current outbreak of Mountain Pine Beetle, Dendroctonus ponderosae Hopkins, has led to extensive tree mortality in British Columbia and the western United States. While the greatest impacts of the outbreak have been in British Columbia, ongoing impacts are expected as the outbreak continues to spread eastward towards Canada's boreal and eastern Pine forests. Successful mitigation of this outbreak is dependent on understanding how the Beetle's host selection behaviour is influenced by the patchwork of tree mortality across the landscape. While several studies have shown that selective mechanisms operate at the individual tree level, less attention has been given to Beetles' preference for variation in spatial forest patterns, namely forest fragmentation, and if such preference changes with changing population conditions. The objective of this study is to explore the influence of fragmentation on the location of Mountain Pine Beetle caused mortality. Using a negative binomial regression model, we tested the significance of a fragmentation measure called the Aggregation Index for predicting Beetle-caused tree mortality in the central interior of British Columbia, Canada in 2000 and 2005. The results explain that Mountain Pine Beetle
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spatial temporal analysis of species range expansion the case of the Mountain Pine Beetle dendroctonus ponderosae
Journal of Biogeography, 2009Co-Authors: Colin Robertson, Michael A. Wulder, Trisalyn A Nelson, Dennis E Jelinski, Barry BootsAbstract:Aim The spatial extent of western Canada’s current epidemic of Mountain Pine Beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is increasing. The roles of the various dispersal processes acting as drivers of range expansion are poorly understood for most species. The aim of this paper is to characterize the movement patterns of the Mountain Pine Beetle in areas where range expansion is occurring, in order to describe the fine-scale spatial dynamics of processes associated with Mountain Pine Beetle range expansion. Location Three regions of Canada’s Rocky Mountains: Kicking Horse Pass, Yellowhead Pass and Pine Pass. Methods Data on locations of Mountain Pine Beetle-attacked trees of predominantly lodgepole Pine (Pinus contorta var. latifolia) were obtained from annual fixed-wing aircraft surveys of forest health and helicopter-based GPS surveys of Mountain Pine Beetle-damaged areas in British Columbia and Alberta. The annual (1999–2005) spatial extents of outbreak ranges were delineated from these data. Spatial analysis was conducted using the spatial–temporal analysis of moving polygons (STAMP), a recently developed pattern-based approach. Results We found that distant dispersal patterns (spot infestations) were most often associated with marginal increases in the areal size of Mountain Pine Beetle range polygons. When the Mountain Pine Beetle range size increased rapidly relative to the years examined, local dispersal patterns (adjacent infestation) were more common. In Pine Pass, long-range dispersal (> 2 km) markedly extended the north-east border of the Mountain Pine Beetle range. In Yellowhead Pass and Kicking Horse Pass, the extension of the range occurred incrementally via ground-based spread. Main conclusions Dispersal of Mountain Pine Beetle varies with geography as well as with host and Beetle population dynamics. Although colonization is mediated by habitat connectivity, during periods of low overall habitat expansion, dispersal to new distant locations is common, whereas during periods of rapid invasion, locally connected spread is the dominant mode of dispersal. The propensity for long-range transport to establish new Beetle populations, and thus to be considered a driver of range expansion, is likely to be determined by regional weather patterns, and influenced by local topography. We conclude that STAMP appears to be a useful approach for examining changes in biogeograpical ranges, with the potential to reveal both fine- and large-scale patterns.
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Considering the effectiveness of Mountain Pine Beetle mitigation strategies
2008Co-Authors: Nicholas C Coops, Michael A. Wulder, Joanne C White, Joleen Timko, Stephanie M. OrtleppAbstract:In this communication, we review a broad range of mitigation strategies associated with the management of Mountain Pine Beetle (Dendroctonus ponderosae Hopkins). We consider methods that are currently utilized or proposed for controlling Beetle populations, the manner in which the effectiveness of these approaches is monitored and assessed and, finally, the role that remotely sensed data may play in a large-area monitoring system. To this end, we first review the goals of effectiveness monitoring and introduce a general classification system to clarify the purpose and practice of efficacy monitoring. Based on these principles, the review is then structured around effectiveness evaluations for managing forest pests, primarily Mountain, southern, and western Pine Beetles throughout North America. These evaluations are grouped by management strategy: silvicultural treatments; prescribed burns; and the use of attractants, repellants, and insecticides. Finally, we propose the use of remotely sensed data as a complementary tool for monitoring changes in the extent and severity of Mountain Pine Beetle damage across large areas. Use of such data enables assessment of the efficacy of landscape level management practices, direction of the application of new mitigation activities, and reduction of the risk of future infestations.
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detecting Mountain Pine Beetle red attack damage with eo 1 hyperion moisture indices
Journal of remote sensing, 2007Co-Authors: Joanne C White, Michael A. Wulder, Nicholas C Coops, Thomas Hilker, Allan L CarrollAbstract:The Mountain Pine Beetle (Dendroctonus ponderosae) is the most destructive insect of mature Pine forests in western North America. Time series of wetness transformations generated from Landsat imagery have been used to detect Mountain Pine Beetle red attack damage over large areas. With the recent availability of high spatial (QuickBird) and high spectral (Hyperion) resolution satellite sensor imagery, the relationship between spectral moisture indices and levels of red attack damage may be investigated. Six moisture indices were generated from Hyperion data and were compared to the proportion of the Hyperion pixel having red attack damage. Results indicate the Hyperion moisture indices incorporating both the shortwave infrared (SWIR) and near infrared (NIR) regions of the electromagnetic spectrum concurrently, such as the Moisture Stress Index, were significantly correlated to levels of damage (r 2 = 0.51; p = 0.0001). The results corroborate the hypothesis that changes in foliage moisture resulting from Mountain Pine Beetle attack are driving the broad-scale temporal variation in Landsat derived wetness indices. Furthermore, the results suggest that Hyperion data may be used to map low levels of Mountain Pine Beetle red attack damage over large areas that are not consistently captured with Landsat data.
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Environmental characteristics of Mountain Pine Beetle infestation hot spots
Journal of Ecosystems and Management, 2007Co-Authors: Trisalyn A Nelson, Michael A. Wulder, Barry Boots, Allan L CarrollAbstract:A combination of favourable temperatures and abundant host trees has resulted in a Mountain Pine Beetle ( Dendroctonus ponderosae Hopkins) epidemic over the majority of the lodgepole Pine forests of British Columbia, Canada. Understanding temporal trends in the interactions between Mountain Pine Beetle infestations and landscape characteristics can improve our understanding of Beetle biology, inform modelling of future impacts, and support management. In this paper, we demonstrate a practical technique for characterizing spatial interactions between Beetles and the environment. The locations with the highest-intensity infestations (hot spots) were identified using point data derived from annual helicopter-based surveys of Beetle-infested Pine, and a kernel density estimator. By examining the environmental characteristics associated with hot spots through time, an increased understanding of how the Mountain Pine Beetle utilizes resources over large areas is generated. The effect of treatment on the persistence of hot spots is also explored. Results indicate that Beetles intensely infest mature trees with a shift to younger trees over time. Hot-spot locations are most commonly associated with stands composed of 30–80% Pine and almost always occur at elevations between 800 m and 1000 m. In the early years of an infestation, hot spots are typically found on warmer (south and west) aspects. As well, relative to non-treatment, any type of treatment reduces the persistence of hot spots the following year.
Jose F. Negron - One of the best experts on this subject based on the ideXlab platform.
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Within-Stand Distribution of Tree Mortality Caused by Mountain Pine Beetle, Dendroctonus ponderosae Hopkins
Insects, 2020Co-Authors: Jose F. NegronAbstract:The Mountain Pine Beetle (MPB) (Dendroctonus ponderosae) is a bark Beetle that attacks and kills ponderosa Pine (Pinus ponderosa), among other Pine species throughout the western conifer forests of the United States and Canada, particularly in dense stands comprising large trees. There is information on the stand conditions that the insect prefers. However, there is a paucity of information on how small-scale variation in stand conditions influences the distribution of tree mortality within a stand. I examined the small-scale distribution of ponderosa Pine basal area pre- and post a Mountain Pine Beetle infestation, and used geostatistical modeling to relate the spatial distribution of the host to subsequent MPB-caused tree mortality. Results indicated increased mortality in the denser parts of the stand. Previous land management has changed historically open low-elevation ponderosa Pine stands with aggregated tree distribution into dense stands that are susceptible to Mountain Pine Beetles and intense fires. Current restoration efforts are aimed at reducing tree density and leaving clumps of trees, which are more similar to historical conditions. The residual clumps, however, may be susceptible to Mountain Pine Beetle populations. Land managers will want to be cognizant of how Mountain Pine Beetles will respond to restoration treatments, so as to prevent and mitigate tree mortality that could negate restoration efforts.
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Phoretic symbionts of the Mountain Pine Beetle (Dendroctonus ponderosae Hopkins)
Forest Science, 2014Co-Authors: Javier E. Mercado, Richard W. Hofstetter, Danielle M. Reboletti, Jose F. NegronAbstract:During its life cycle, the tree-killing Mountain Pine Beetle Dendroctonus ponderosae Hopkins interacts with phoretic organisms such as mites, nematodes, fungi, and bacteria. The types of associations these organisms establish with the Mountain Pine Beetle (MPB) vary from mutualistic to antagonistic. The most studied of these interactions are those between Beetle and fungi. The least studied are interactions with bacteria, but these have received increased attention recently. Nematodes remain little studied. We reviewed the significant literature pertaining to MPB phoronts. A number of potentially important interactions and contributions resulting from associations between MPB and its phoronts are discussed. A wealth of literature exists on this topic, yet many questions remain unanswered, and the effects of some phoronts on population levels remain unexplored.
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A Comment on “Management for Mountain Pine Beetle Outbreak Suppression: Does Relevant Science Support Current Policy?”
Forests, 2014Co-Authors: Christopher J Fettig, Kenneth E. Gibson, A. Steven Munson, Jose F. NegronAbstract:There are two general approaches for reducing the negative impacts of Mountain Pine Beetle, Dendroctonus ponderosae Hopkins, on forests. Direct control involves short-term tactics designed to address current infestations by manipulating Mountain Pine Beetle populations, and includes the use of fire, insecticides, semiochemicals, sanitation harvests, or a combination of these treatments. Indirect control is preventive, and designed to reduce the probability and severity of future infestations within treated areas by manipulating stand, forest and/or landscape conditions by reducing the number of susceptible host trees through thinning, prescribed burning, and/or alterations of age classes and species composition. We emphasize that ―outbreak suppression‖ is not the intent or objective of management strategies implemented for Mountain Pine Beetle in the western United States, and that the use of clear, descriptive language is important when assessing the merits of various treatment strategies.
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evaluating potential fire behavior in lodgepole Pine dominated forests after a Mountain Pine Beetle epidemic in north central colorado
Western Journal of Applied Forestry, 2011Co-Authors: Jennifer G. Klutsch, Mike A Battaglia, Daniel R West, Sheryl L Costello, Jose F. NegronAbstract:A Mountain Pine Beetle outbreak in Colorado lodgepole Pine forests has altered stand and fuel characteristics that affect potential fire behavior. Using the Fire and Fuels Extension to the Forest Vegetation Simulator, potential fire behavior was modeled for uninfested and Mountain Pine Beetle-affected plots 7 years after outbreak initiation and 10 and 80% projected tree fall using measured and projected fuel and stand characteristics. Under 90th percentile weather conditions, uninfested plots exhibited proportionally more crown fire than infested plots. Plots predicted to have crown fire were composed mainly of nonhost conifer species and had a lower and more continuous canopy than infested plots. Where surface fire was predicted to occur, live lodgepole Pine was the only conifer present, and plots had significantly lower tree mortality from fire than plots predicted to have crown fire. Mountain Pine Beetle-induced changes in stand and fuel characteristics resulted in increased intensity of surface fire behavior. Furthermore, with 80% infested tree fall, potential smoke production was predicted to be higher. Tree species composition of stands pre and postbark Beetle outbreak is important when identifying Mountain Pine Beetle-caused changes to potential fire behavior.
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stand characteristics and downed woody debris accumulations associated with a Mountain Pine Beetle dendroctonus ponderosae hopkins outbreak in colorado
Forest Ecology and Management, 2009Co-Authors: Jennifer G. Klutsch, Jose F. Negron, John B Popp, Daniel R West, Sheryl L Costello, Charles C Rhoades, Rick CaissieAbstract:Lodgepole Pine (Pinus contorta Dougl. ex Loud.)-dominated ecosystems in north-central Colorado are undergoing rapid and drastic changes associated with overstory tree mortality from a current Mountain Pine Beetle (Dendroctonus ponderosae Hopkins) outbreak. To characterize stand characteristics and downed woody debris loads during the first 7 years of the outbreak, 221 plots (0.02 ha) were randomly established in infested and uninfested stands distributed across the Arapaho National Forest, Colorado. Mountain Pine Beetle initially attacked stands with higher lodgepole Pine basal area, and lower density and basal area of Engelmann spruce (Picea engelmannii (Parry)), and subalPine fir (Abies lasiocarpa (Hook.) Nutt. var. lasiocarpa) compared to uninfested plots. Mountain Pine Beetle-affected stands had reduced total and lodgepole Pine stocking and quadratic mean diameter. The density and basal area of live overstory lodgepole declined by 62% and 71% in infested plots, respectively. The mean diameter of live lodgepole Pine was 53% lower than pre-outbreak in infested plots. Downed woody debris loads did not differ between uninfested plots and plots currently infested at the time of sampling to 3 or 4-7 years after initial infestation, but the projected downed coarse wood accumulations when 80% of the Mountain Pine Beetle-killed trees fall indicated a fourfold increase. Depth of the litter layer and maximum height of grass and herbaceous vegetation were greater 4-7 years after initial infestation compared to uninfested plots, though understory plant percent cover was not different. Seedling and sapling density of all species combined was higher in uninfested plots but there was no difference between infested and uninfested plots for lodgepole Pine alone. For trees � 2.5 cm in diameter at breast height, the density of live lodgepole Pine trees in Mountain Pine Beetle-affected stands was higher than Engelmann spruce, subalPine fir, and aspen, (Populus tremuloides Michx.), in diameter classes comprised of trees from 2.5 cm to 30 cm in diameter, suggesting that lodgepole Pine will remain as a dominant overstory tree after the bark Beetle outbreak. Published by Elsevier B.V.