| composition of gum turpentines of pines. xiii. a report on pinus albicaulis. | | 1951 | 14907458 |
| pollen sequence from late quaternary sediments in yellowstone park. | a radiocarbon-dated pollen diagram from a depression near the end of the southeast arm of yellowstone lake, wyoming, records the vegetation sequence from the retreat of late wisconsin (pinedale) ice to the present time. the tundra picea-abies-pinus albicaulis (spruce-fir-whitebark pine) parkland vegetation inferred during late glacial time changed rapidly to a pinus contorta (lodgepole pine) forest shortly before 11,550 carbon-14 years ago, suggesting a warming trend at that time. the pinus cont ... | 1970 | 17731592 |
| extreme environmental variation sharpens selection that drives the evolution of a mutualism. | the importance of infrequent events for both adaptive evolution and the evolution of species interactions is largely unknown. we investigated how the infrequent production of large seed crops (masting) of a bird-dispersed tree (whitebark pine, pinus albicaulis) influenced phenotypic selection exerted by its primary avian seed predator-disperser, the clark's nutcracker (nucifraga columbiana). selection was not evident during common years of low seed abundance, whereas it was replicated among area ... | 2007 | 17519187 |
| hydraulic compensation in northern rocky mountain conifers: does successional position and life history matter? | as trees grow tall and the resistance of the hydraulic pathway increases, water supply to foliage may decrease forcing stomata to close and co2 uptake to decline. several structural (e.g. biomass allocation) and physiological adjustments, however, may partially or fully compensate for such hydraulic constraints and prevent limitations on co2 uptake and growth. the degree to which trees compensate for hydraulic constraints as they grow tall may depend on the costs and benefits associated with hyd ... | 2006 | 16639568 |
| investigating the evolutionary history of the pacific northwest mesic forest ecosystem: hypothesis testing within a comparative phylogeographic framework. | we examine the evolution of mesic forest ecosystems in the pacific northwest of north america using a statistical phylogeography approach in four animal and two plant lineages. three a priori hypotheses, which explain the disjunction in the mesic forest ecosystem with either recent dispersal or ancient vicariance, are tested with phylogenetic and coalescent methods. we find strong support in three amphibian lineages (ascaphus spp., and dicampton spp., and plethodon vandykei and p. idahoensis) fo ... | 2005 | 16331838 |
| dna from bird-dispersed seed and wind-disseminated pollen provides insights into postglacial colonization and population genetic structure of whitebark pine (pinus albicaulis). | uniparentally inherited mitochondrial (mt)dna and chloroplast (cp)dna microsatellites (cpssrs) were used to examine population genetic structure and biogeographic patterns of bird-dispersed seed and wind-disseminated pollen of whitebark pine (pinus albicaulis engelm.). sampling was conducted from 41 populations throughout the range of the species. analyses provide evidence for an ancestral haplotype and two derived mtdna haplotypes with distinct regional distributions. an abrupt contact zone bet ... | 2002 | 11856423 |
| water use by whitebark pine and subalpine fir: potential consequences of fire exclusion in the northern rocky mountains. | in subalpine forests of the northern rocky mountains, fire exclusion has contributed to large-scale shifts from early-successional whitebark pine (pinus albicaulis engelm.) to late-successional subalpine fir (abies lasiocarpa (hook.) nutt.), a species assumed to be more shade tolerant than whitebark pine and with leaf to sapwood area ratios (a(l):a(s)) over twice as high. potential consequences of high a(l):a(s) for subalpine fir include reduced light availability and, if hydraulic sufficiency i ... | 2001 | 11470657 |
| temperature-driven range expansion of an irruptive insect heightened by weakly coevolved plant defenses. | warming climate has increased access of native bark beetles to high-elevation pines that historically received only intermittent exposure to these tree-killing herbivores. here we show that a dominant, relatively naïve, high-elevation species, whitebark pine, has inferior defenses against mountain pine beetle compared with its historical lower-elevation host, lodgepole pine. lodgepole pines respond by exuding more resin and accumulating higher concentrations of toxic monoterpenes than whitebark ... | 2012 | 23277541 |
| the push-pull tactic for mitigation of mountain pine beetle (coleoptera: curculionidae) damage in lodgepole and whitebark pines. | in an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (pinus contorta douglas ex loudon) and whitebark pine (pinus albicaulis engelm.) stands from attack by mountain pine beetle (dendroctonus ponderosae hopkins) in two studies. the first was conducted on replicated 4.04-ha plots in lodgepole pine stands (california, 2008) and the second on 0.81-ha plots in whitebar ... | 2012 | 23321106 |
| Variability in chemical composition and abundance of the rare tertiary relict Pinus heldreichii in Serbia. | The particular significance of the whitebark pine (Pinus heldreichii Christ.) stems from the fact that it is a tertiary relict and Balkanic subendemite covering a very narrow and intermittent area in Serbia. A representative pool of 48 adult trees originating from three populations, one recently discovered natural (Population I) and two planted populations (Populations II and III) was investigated in order to evaluate the intra- and interpopulation variability of the essential oil of the complet ... | 2011 | 21922664 |
| an ecosystem-scale model for the spread of a host-specific forest pathogen in the greater yellowstone ecosystem. | the introduction of nonnative pathogens is altering the scale, magnitude, and persistence of forest disturbance regimes in the western united states. in the high-altitude whitebark pine (pinus albicaulis) forests of the greater yellowstone ecosystem (gye), white pine blister rust (cronartium ribicola) is an introduced fungal pathogen that is now the principal cause of tree mortality in many locations. although blister rust eradication has failed in the past, there is nonetheless substantial inte ... | 2011 | 21774419 |
| ecological genetics and seed transfer guidelines for pinus albicaulis (pinaceae). | whitebark pine (pinus albicaulis engelm.) has greatly declined throughout its range as a result of introduced disease, fire suppression, and other factors, and climate change is predicted to accelerate this decline. restoration is needed; however, no information regarding the degree of local adaptation is available to guide these efforts. a seedling common-garden experiment was employed to assess genetic diversity and geographic differentiation (q(st)) of whitebark pine for traits involved in gr ... | 2008 | 21632316 |
| cone and seed trait variation in whitebark pine (pinus albicaulis; pinaceae) and the potential for phenotypic selection. | phenotypic variation among individuals is necessary for natural selection to operate and is therefore essential for adaptive evolution. however, extensive variation within individuals can mask variation among individuals and weaken the potential for selection. here we quantify variation among and within individuals in female cone and seed traits of whitebark pine (pinus albicaulis). in many plants, the production of numerous reproductive structures creates the potential for considerable variatio ... | 2009 | 21628255 |
| whitebark pine vulnerability to climate-driven mountain pine beetle disturbance in the greater yellowstone ecosystem. | widespread outbreaks of mountain pine beetles (mpb) are occurring throughout the range of this native insect. episodic outbreaks are a common occurrence in the beetles' primary host, lodgepole pine. current outbreaks, however, are occurring in habitats where outbreaks either did not previously occur or were limited in scale. herein, we address widespread, ongoing outbreaks in high-elevation, whitebark pine forests of the greater yellowstone ecosystem, where, due to an inhospitable climate, past ... | 2010 | 20597278 |
| tree squirrel habitat selection and predispersal seed predation in a declining subalpine conifer. | differential responses by species to modern perturbations in forest ecosystems may have undesirable impacts on plant-animal interactions. if such disruptions cause declines in a plant species without corresponding declines in a primary seed predator, the effects on the plant could be exacerbated. we examined one such interaction between pinus albicaulis (whitebark pine), a bird-dispersed, subalpine forest species experiencing severe population declines in the northern part of its range, and tami ... | 2010 | 19916026 |
| invasive pathogen threatens bird-pine mutualism: implications for sustaining a high-elevation ecosystem. | human-caused disruptions to seed-dispersal mutualisms increase the extinction risk for both plant and animal species. large-seeded plants can be particularly vulnerable due to highly specialized dispersal systems and no compensatory regeneration mechanisms. whitebark pine (pinus albicaulis), a keystone subalpine species, obligately depends upon the clark's nutcracker (nucifraga columbiana) for dispersal of its large, wingless seeds. clark's nutcracker, a facultative mutualist with whitebark pine ... | 2009 | 19425424 |
| seed predation and selection exerted by a seed predator influence subalpine tree densities. | strongly interacting species often have pronounced direct and indirect effects on other species. here we focus of the effects of pine squirrels (tamiasciurus spp.), which are a dominant pre-dispersal seed predator of many conifers including limber pines (pinus flexilis) and whitebark pines (p. albicaulis). pine squirrels depress seed abundance by harvesting most limber and whitebark pine cones on their territories. pine squirrels further reduce seed availability for clark's nutcrackers (nucifrag ... | 2008 | 18959333 |
| genetic specificity in the white pine-blister rust pathosystem. | abstract four of eight white pine species native to western north america surveyed for resistance to white pine blister rust by artificial inoculation showed classical hypersensitive reactions (hr) at frequencies ranging from very low to moderate. mendelian segregation, indicating a single dominant allele for resistance (cr3), was observed in southwestern white pine (pinus strobiformis), as it was previously in sugar pine (p. lambertiana, cr1) and western white pine (p. monticola, cr2). hr was p ... | 2002 | 18943999 |
| synergistic blends of monoterpenes for aggregation pheromones of the mountain pine beetle (coleoptera: curculionidae). | the superiority of the host monoterpene myrcene as a synergist for trans-verbenol and exo-brevicomin, aggregation pheromone components of the mountain pine beetle, dendroctonus ponderosae hopkins (coleoptera: curculionidae), suggests that the ancestral host of the mountain pine beetle is a pine rich in myrcene. a field trapping experiment in british columbia testing reconstituted bole oleoresin of whitebark pine, pinus albicaulis engelmann, composed of mainly myrcene (20.7%), terpinolene (6.8%), ... | 2008 | 18767736 |
| interspecific phylogenetic analysis enhances intraspecific phylogeographical inference: a case study in pinus lambertiana. | pinus lambertiana (sugar pine) is an economically and ecologically important conifer with a 1600-km latitudinal range extending from oregon, usa, to northern baja california, mexico. like all north american white pines (subsect. strobus), sugar pine is highly susceptible to white pine blister rust, a disease caused by the fungus cronartium ribicola. we conducted a chloroplast dna (cpdna) survey of pinus subsect. strobus with comprehensive geographical sampling of p. lambertiana. sequence analysi ... | 2007 | 17850554 |
| variability of the needle essential oils of pinus heldreichii from different populations in montenegro and serbia. | the essential-oil compositions of pinus heldreichii christ. from montenegro and serbia are reported at the population level. whitebark pine is a sub-endemic high-mountain balkan pine relict of an anthropogenically reduced area, with large morphological diversity and insufficiently clear taxonomic position. in the pine-needle terpene profile from three populations from montenegro, and one from serbia, 101 compounds were detected, 72 of which could be identified (table 3). the dominant constituent ... | 2007 | 17510986 |
| a test of high-dose verbenone for stand-level protection of lodgepole and whitebark pine from mountain pine beetle (coleoptera: curculionidae: scolytinae) attacks. | the efficacy of verbenone as a stand-level protectant against mountain pine beetle, dendroctonus ponderosae hopkins, attacks was tested in lodgepole and whitebark pine stands at five geographically separated sites, including three consecutive years at one site. forty and 20 high-dose pouches, with a verbenone emission rate up to 50 mg/d per pouch, were spaced in a grid pattern throughout 0.40-ha plots, replicated up to six times at each site. although the verbenone treatment did not prevent beet ... | 2005 | 16334331 |