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Effective management of bark beetle infestations requires prompt detection of attacked trees. Early attack is also called green attack, since tree foliage does not yet show any visible signs of tree decline. In several bark beetle systems, including mountain pine beetle and European spruce bark beetle, unpiloted aerial vehicle (UAV)-based remote sensing has successfully detected early attack. We explore the utility of remote sensing for early attack detection of southern pine beetle (SPB; Dendroctonus frontalis Zimm.), paired with detailed ground surveys to link tree decline symptoms with SPB life stages within the tree. In three of the northernmost SPB outbreaks in 2022 (Long Island, New York), we conducted ground surveys every two weeks throughout the growing season and collected UAV-based multispectral imagery in July 2022. Ground data revealed that SPB-attacked pitch pines (Pinus rigida Mill.) generally maintained green foliage until SPB pupation occurred within the bole. This tree decline behavior illustrates the need for early attack detection tools, like multispectral imagery, in the beetle's northern range. Balanced random forest classification achieved, on average, 78.8% overall accuracy and identified our class of interest, SPB early attack, with 68.3% producer's accuracy and 72.1% user's accuracy. After removing the deciduous trees and just mapping the pine, the overall accuracy, on average, was 76.9% while the producer's accuracy and the user's accuracy both increased for the SPB early attack class. Our results demonstrate the utility of multispectral remote sensing in assessing SPB outbreaks, and we discuss possible improvements to our protocol. This is the first remote sensing study of SPB early attack in almost 60 years, and the first using a UAV in the SPB literature. [ABSTRACT FROM AUTHOR]

For the purposes of chemotaxonomic distinction of four pine species Pinus nigra, Pinus ponderosa, Pinus rigida and Pinus sylvestris growing in the suburban landscape of the central part of the Czech Republic, resin extracts from tree trunks, needles and female cones were analysed using gas chromatography-mass spectroscopy. Monoterpenes were shown to be the main terpene fraction of the resins of all studied pine species. On average, they made up 80% of the total terpene content. A characteristic monoterpene for distinguishing pine species was β-pinene, with high levels in P. ponderosa, moderate levels in P. rigida and low levels in P. sylvestris and P. nigra. P. sylvestris contained only trace amount of Δ-3-carene (0.6%) in resins from needles and thus belongs to the α-pinene chemotypic variation. Slight seasonal variability in terpene production was found for resins from needles of P. nigra and P. sylvestris. When comparing European populations according to the monoterpene composition of resins from needles, it can be stated that the α-pinene content increased in the order P. ponderosa < P. rigida < P. nigra < P. sylvestris while the β-pinene content changed in the opposite direction. This statement confirms the terpene biosynthesis uniformity of European pines. [ABSTRACT FROM AUTHOR]

Pitch pine (Pinus rigida Mill.) can be found across a broad range in eastern North America but assumes local dominance only on poor soils in the northeastern United States. Contemporary management goals in the Northeast for areas dominated by pitch pine are focused on noncommercial benefits of forests, such as carbon density, reduced wildfire risk, habitat for rare species, and water provisioning. We present a density management diagram that empirically articulates the size-density limits of even-aged pitch pine stands. Included in the diagram are wildfire risk and carbon density, which are inversely related for most stand sizes. Maximum possible aboveground live tree carbon begins to decline at a quadratic mean diameter greater than 9 in. while crown fire risk remains high along the size-density limit until a quadratic mean diameter above 12 in. is achieved. Study Implications: Modern silvicultural tools that illustrate forest stand conditions have not been developed for pitch pine, but this species occurs in a region with much public attention on forests. We develop and present a density management diagram to show the interplay of different social goals for the forest and how they relate to the maximum size-density relationship. Pitch pine stands with high levels of aboveground live carbon are at high risk of crown fire, particularly in the smaller size classes. [ABSTRACT FROM AUTHOR]

Effective management of bark beetle infestations requires prompt detection of attacked trees. Early attack is also called green attack, since tree foliage does not yet show any visible signs of tree decline. In several bark beetle systems, including mountain pine beetle and European spruce bark beetle, unpiloted aerial vehicle (UAV)-based remote sensing has successfully detected early attack. We explore the utility of remote sensing for early attack detection of southern pine beetle (SPB; Dendroctonus frontalis Zimm.), paired with detailed ground surveys to link tree decline symptoms with SPB life stages within the tree. In three of the northernmost SPB outbreaks in 2022 (Long Island, New York), we conducted ground surveys every two weeks throughout the growing season and collected UAV-based multispectral imagery in July 2022. Ground data revealed that SPB-attacked pitch pines (Pinus rigida Mill.) generally maintained green foliage until SPB pupation occurred within the bole. This tree decline behavior illustrates the need for early attack detection tools, like multispectral imagery, in the beetle’s northern range. Balanced random forest classification achieved, on average, 78.8% overall accuracy and identified our class of interest, SPB early attack, with 68.3% producer’s accuracy and 72.1% user’s accuracy. After removing the deciduous trees and just mapping the pine, the overall accuracy, on average, was 76.9% while the producer’s accuracy and the user’s accuracy both increased for the SPB early attack class. Our results demonstrate the utility of multispectral remote sensing in assessing SPB outbreaks, and we discuss possible improvements to our protocol. This is the first remote sensing study of SPB early attack in almost 60 years, and the first using a UAV in the SPB literature.

AbstractThe importance of a quantitative assessment of C and N contents of dead wood is increasing in forest ecosystems. This study aimed to determine the density and carbon (C) and nitrogen (N) status of dead wood with decay class for three pine species (Pinus densiflora, Pinus rigida, and Pinus koraiensis) in southern Korea. The C concentration in dead wood was significantly different among species (P. densiflora, 50.31%; P. koraiensis, 47.22%; P. rigida, 44.96%), whereas decay class did not affect the C concentration (p > 0.05). The density and C content of dead wood in all species decreased with increasing decay class. The N concentrations of dead wood increased more rapidly in P. rigida and P. koraiensis than in P. densiflora, with an increasing decay class. Thus, the N content of dead wood was unchanged or increased in P. rigida and P. koraiensis, whereas that of P. densiflora decreased because of density reduction with increasing decay class. Our results indicate that the unchanged, increased, or decreased status of C and N in dead wood depends on the species and decay class.

Climate change is facilitating a novel range expansion of southern pine beetle (SPB) into globally rare north‐eastern pitch pine barrens.By assessing stand conditions present in SPB‐infested and uninfested pitch pine stands on Long Island, NY, USA, we developed a regionally‐calibrated hazard rating model that predicts stand‐level SPB susceptibility.The model indicates that a stand's SPB susceptibility increases with (1) increasing pitch pine basal area, (2) increasing instances of previous year SPB spots nearby, and (3) sandy soil texture.The model informs adaptation strategies to a novel pest dynamic by supporting the identification and prioritization of high hazard stands for prevention management.An alignment between treatments effective in reducing SPB vulnerability and conserving pine barrens communities indicates that pine barrens can be managed both to improve resilience to future threats and preserve historic ecological conditions. [ABSTRACT FROM AUTHOR]

Long-lived species of trees, especially conifers, often display weak patterns of reproductive isolation, but clear patterns of local adaptation and phenotypic divergence. Discovering the evolutionary history of these patterns is paramount to a generalized understanding of speciation for long-lived plants. We focus on two closely related yet phenotypically divergent pine species, Pinus pungens and P. rigida, that co-exist along high elevation ridgelines of the southern Appalachian Mountains. In this study, we performed historical species distribution modeling (SDM) to form hypotheses related to population size change and gene flow to be tested in a demographic inference framework. We further sought to identify drivers of divergence by associating climate and geographic variables with genetic structure within and across species boundaries. Population structure within each species was absent based on genome-wide RADseq data. Signals of admixture were present range-wide, however, and species-level genetic differences associated with precipitation seasonality and elevation. When combined with information from contemporary and historical species distribution models, these patterns are consistent with a complex evolutionary history of speciation influenced by Quaternary climate. This was confirmed using inferences based on the multidimensional site frequency spectrum, where demographic modeling inferred recurring gene flow since divergence (2.74 million years ago) and population size reductions that occurred during the last glacial period (~ 35.2 thousand years ago). This suggests that phenotypic and genomic divergence, including the evolution of divergent phenological schedules leading to partial reproductive isolation, as previously documented for these two species, can happen rapidly, even between long-lived species of pines. [ABSTRACT FROM AUTHOR]

Pitch pine (Pinus rigida Mill.) is native to North America and has a strong resistance to pine wood nematodes (PWNs). The PWN resistance mechanism of this tree species has yet to be discovered. In this work, we found that the spreading of inoculated PWNs in the branch of P. rigida was significantly suppressed compared to those in the branches of Pinus densiflora (Sieb. et Zucc.) and Pinus koraiensis (Sieb. et Zucc.). Dipping of PWNs in the resins isolated from P. rigida significantly suppressed the PWN mobility and conferred significantly higher PWN mortality compared to those in the resins from P. densiflora and P. koraiensis. All PWNs dipped in P. rigida resin were killed after six days, but more than 50% of the PWNs dipped in the resin from P. densiflora, and P. koraiensis were still alive after six days. The phytochemical analysis of resins revealed that P. rigida resin contained little or no amount of sesquiterpenes compared to those from P. densiflora and P. koraiensis. However, P. rigida resin contained rich amounts of diterpenes, among which dehydroabietic aldehyde, methyl dehydroabietate, and methyl abietate were uniquely detected. Particularly, two pinosylvin stilbenes (trans and cis-3,5-dimethoxystilbene) were accumulated in P. rigida resin, which were not detected in the resins from P. densiflora and P. koraiensis. cis-3,5-Dimethoxystilbene showed high nematicidal activity but not in trans-3,5-dimethoxystilbene. Conclusively, PWN resistance of P. rigida may be due to the toxic chemicals in the resin, in which cis-3,5-dimethoxystilbene may contribute to PWN toxicity. This work is the first demonstration that resin from PWN-resistant P. rigida directly affected PWN mobility and mortality, probably due to toxic phytochemicals in the resin. [ABSTRACT FROM AUTHOR]

Fire is a strong ecological and evolutionary driver of plant species and terrestrial ecosystem dynamics. Numerous studies have shown that plant species vary widely in their flammability and associated traits that coincide with clear strategies of persistence in fire‐prone ecosystems. Yet, intraspecific variation and phenotypic plasticity in plant flammability has received substantially less attention. Some evidence has demonstrated high plasticity in flammability among populations in species adapted to low‐frequency, high severity fire regimes which suggests the capacity of local adaptation; however, intraspecific variability of species in high‐frequency, low severity fire regimes has not been conducted. Given that frequent fire‐adaptive species tend to produce fast‐flammable litter that is associated with survival following fire, we hypothesized that these species would have highly conserved leaf traits with low variation in litter flammability.We used an existing common garden study to test our hypothesis in Pinus rigida (pitch pine) with source populations that span most of its distribution in eastern North America. We examined both phenotypic and genotypic variation as well as phenotypic plasticity (relative distance plasticity index) in P. rigida leaf traits and litter flammability among populations grown in situ (population) and the same populations grown in a common garden or provenance study (provenance).Phenotypic and genotypic variation in fuel traits and litter flammability differed among source locations. Phenotypic plasticity in litter flammability among source locations were associated with fuel trait plasticity and biogeographic factors. Populations located in warmer and drier climates with presumably more frequent historical fire regimes were associated with greater plasticity in physical litter traits and their resulting flammability.Synthesis. Our study demonstrates the utility of common garden experiments to examine intraspecific variation and phenotypic plasticity in litter flammability. Our results indicate that litter flammability in Pinus rigida has the capacity for local adaptation. We hypothesize that intraspecific variation in plant flammability provides ecologically and evolutionary relevant information and that other frequent fire‐adaptive species will similarly demonstrate local adaptation in plant flammability. [ABSTRACT FROM AUTHOR]

Fire-dependent yellow pine (Pinus) forests are included within the temperate deciduous forest of eastern North America. These forests, which occupy dry slopes and typically contain xerophytic oaks (Quercus), have receded under fire suppression. Understanding historical fire regimes is essential for interpreting and managing these stands. To characterize fire history and vegetation dynamics, we conducted a dendroecological study of fire-scarred trees and age structure in pine stands at four sites in the Appalachian Mountains. Fire interval estimates suggest that before fire suppression began in the early to middle 1900s, fires occurred at approximately three- to eleven-year intervals. Short intervals were probably maintained in part by large-extent fires that spread from sparse ignition points. Fire frequency showed no long-term temporal trend (e.g., no wave of fire) from the middle 1700s through early 1900s despite land–use intensification, including industrial logging and associated wildfires during the late nineteenth and early twentieth centuries. Fire occurrence was associated with drought at two sites. Age–structure analyses evoke pyrogenic pine–oak communities that predated industrial disturbances and persisted under a regime of frequent, mixed-severity fires that was likely maintained through a positive feedback with the flammable vegetation. Competing species were established under more recent fire suppression, however, and are poised to replace the pines. [ABSTRACT FROM AUTHOR]

Oak-pine (Quercus L. - Pinus L.) forest communities on low ridges in the southern Appalachian Mountains are losing diversity as mature pitch (P. rigida Mill.) and shortleaf (P. echinata Mill.) pines die and do not regenerate under a hardwood canopy. Restoration of biodiversity by planting pine seedlings is well known, but little is known regarding whether the configuration of planted seedlings affects growth and subsequent size (diameter at breast height, dbh) as trees age. The purpose of this study was to test the hypothesis that pines growing in groups of two or more trees respond with increased growth (expressed by dbh) to intraspecific competition with other pines compared to single trees subjected only to interspecific competition with surrounding hardwoods. For 13-year-old pitch and shortleaf pines, trees were larger in dbh when occurring in groups than trees occurring singly. Regression indicated that intraspecific competition accounted for 16% of the dbh variation of pitch pine and 29% for shortleaf pine. This study originated from chance observations in a small study of pine restoration. If a designed study confirms these results, resource managers could restore biodiversity with reduced site disturbance and establishment costs by planting pine seedlings in small groups rather than rows. [ABSTRACT FROM AUTHOR]

In this study, extractives from Pinus rigida heartwood (PRW), Eucalyptus camaldulensis var. obtusa aerial parts (ECL), and Eucalyptus flower buds (ECF) were used as additives in paper sheets produced from the pulp of linen fibers, and their effects on the mechanical and antifungal properties of the paper sheets were studied. The highest tensile and tear indices were 31.5 Nm/g, and 17.3 mNm2/g as pulp treated with PRW (4%), and ECL (1%), respectively. All the pulp additives yielded lower burst index values compared to the control (2.24 KPa.m2/g); the nearest value was 2.23 KPa.m2/g (ECL 4% pulp additive). The brightness percentages (ISO%) ranged from 65.7% to 70.2%, which were lower than the control treatment (70.3%). The paper sheets produced from pulp treated with 2% or 4% PRW, and with 4% ECL suppressed Aspergillus niger growth on the paper disc; pulp treated with 2% or 4% PRW, 4% ECL, and with 2% or 4% ECF completely suppressed A. terreus growth. However, all pulp extract additives did not inhibit the growth of Fusarium culmorum. [ABSTRACT FROM AUTHOR]

Highlights • We examined impacts of southern pine beetle range expansion on pitch pine barrens. • This novel expansion functionally eliminated Pinus rigida from all canopy layers. • Suppression management reduced mortality, but increased downed, dead fuels. • All impacted sites shifted towards hardwood dominance, especially pine-oak forests. Abstract Southern pine beetle (SPB; Dendroctonus frontalis Zimmerman), a native insect that has historically affected pine (Pinus spp.) ecosystems in the southeastern U.S., has recently expanded northward causing extensive tree mortality in pitch pine (P. rigida) and pitch pine-oak (Quercus spp.) forests of eastern Long Island, NY. Given the historic lack of SPB within this region, little is known regarding its potential impacts. This study examined the immediate effects of SPB-induced tree mortality and management (i.e., cut-and leave suppression) on the structure and composition of affected forest communities to inform management recommendations and projections of future forest conditions. Overstory pine basal area declined significantly following SPB infestation and management (67–100% mortality), although management partly mitigated these effects. There was no immediate impact of SPB or management on seedling and sapling density or composition, with hardwood species making up the majority of this layer and pine representing <6% of stems regardless of mortality agent. Pitch pine was less likely to be browsed by ungulates than white oak and scarlet oak. SPB infestation significantly increased snag basal area, whereas downed woody debris volumes were greatest following management. Understory community composition in pitch pine stands that had SPB or were managed had greater understory plant diversity largely through a higher abundance of disturbance-adapted species. There was less between-site variation in understory species assemblages in pine-oak forests experiencing pitch pine mortality and an increase in regeneration of pitch pine and scarlet oak in these areas. Collectively, the short-term results suggest SPB could functionally eliminate pitch pine from infested stands in the absence of additional management, and that management in pine-oak stands may exacerbate this trend, leading to increasing dominance of hardwoods species in pine barren communities. Based on our results, fuels reduction treatments combined with site-specific restoration of barrens structure and composition may be useful in maintaining stands with lower fire hazard and greater resilience to this new threat. [ABSTRACT FROM AUTHOR]

The Pine Barrens in New York State are dominated by pitch pine (Pinus ridgida) and scrub oaks (Quercus ilicifolia and Q. prinoides). With fire suppression over the last 90 years or so, P. rigida regeneration has become sparse, even in areas set aside to preserve this type of vegetation. We evaluated the effects of fire and an alternative disturbance (mechanical removal of vegetation) for increasing P. rigida regeneration in the Albany Pine Bush Preserve in eastern New York State. By comparing cover, diameter and height of P. rigida, Q. ilicifolia, Q. prinoides, and Vaccinium spp. (blueberry) growing on the sites with a known fire history, we documented structural and compositional changes in the vegetation since its establishment. We also compared sites on which Quercus sprouts were controlled through mechanical removal. In the years following a disturbance, height and cover of Q. ilicifolia increased continuously and the species became increasingly competitive. Both the density of P. rigida seedlings and Vaccinium cover decreased significantly as the diameter and height of Quercus increased. Our results confirmed that the dominance by P. rigida could be attributed to periodic fires at intervals of 20-25 years. We conclude that removing Q. ilicifolia can favor P. rigida dominance on the barren without fire by releasing pine seedlings from competition. [ABSTRACT FROM AUTHOR]

Range expansion of native insect pests under climate change has the potential to move many species beyond their usual habitat. As resource managers attempt to respond to these “new” pests, methods are needed that can rapidly assess local impacts, while utilizing familiar metrics so that the wheel need not be re-invented with each new pest. Southern pine beetle (SPB; Dendroctonus frontalis Zimmermann) is a bark beetle native to the southeastern United States whose periodic outbreaks can kill thousands of hectares of trees, resulting in economic losses and degradation of ecosystem services. Over the past decade, a sustained outbreak in the New Jersey Pinelands has moved the northern limit of its range, switching from forests consisting primarily of loblolly, longleaf, and shortleaf pines ( Pinus taeda , P. palustris, P. echinata ) in the southeastern U.S. to one consisting primarily of pitch pine ( P. rigida ) along the mid-Atlantic seaboard. We sought to understand the effects of forest type and structure on the variation in susceptibility of stands to SPB infestation. We found that among wetland conifer, wetland mixed pine/oak, upland (dry) conifer, and upland mixed pine/oak stands, those with a high percentage of pine were infested with higher probability than mixed pine/hardwood stands, regardless of whether the stands were upland or wetland habitats. The effects of stand type (wetland or upland) were overridden by the effect of stand composition. Research from the south has found that wet or waterlogged stands tend to be more susceptible to SPB, potentially due to lower tree defenses. Our finding that wetland/upland status is less important than stand composition suggests that defenses were not the primary determinant of stand susceptibility. Also in contrast to southern findings, site index did not predict infestation status. More in line with previous work in the south, we found that stands with high percentage pine and high pine basal area were more susceptible. Stands composed of smaller, closer together, shorter, and younger trees, with lower percent live crown, were also more susceptible. Discriminant analyses found that a simple model including DBH, pine basal area, and percent live crown could be used to successfully separate and prioritize stands more likely to be infested in the future. Our results suggest that thinning is an appropriate management strategy for forest managers seeking to build resilience, and that all else being equal, conifer stands should receive priority for management attention over mixed stands. [ABSTRACT FROM AUTHOR]

Fire history reconstructions provide fire managers with valuable information regarding historical fire regime dynamics. Yet, in the Central Hardwood Forest Region (CHF), there is an absence of dendroecological studies where frequent wildfires have persisted into the twenty-first century. This study presents the first documented tree-ring reconstruction of fire history in the Pennsylvania anthracite coal-producing region. An approximately 150-year fire chronology was developed from fire-scarred pitch pine (Pinus rigida) and sassafras (Sassafras albidum) collected on Spring Mountain in Schuylkill County. Principal component analysis andk-means cluster analysis were used to identify four fire regime clusters based on interacting fire and non-fire parameters. Results indicate that fires occurred under a variety of moisture conditions and that a mid-twentieth century increase in fire activity on Spring Mountain was associated with the collapse of the regional anthracite industry and possibly amplified by the 1960s drought. Fires continue to burn on Spring Mountain in the twenty-first century, contrary to the dominant pattern of fire exclusion across the CHF. Future research needs are highlighted regarding historical fire regime dynamics and cultural ties to landscape burning in the Pennsylvania Anthracite Region. [ABSTRACT FROM PUBLISHER]

The mesosphytic forests of eastern North America represent a forest region characterized by dramatic 20th century changes in disturbance regimes, notably the exclusion of fire. Tree-ring reconstructions of forest disturbance can inform restoration and management plans by placing these changes into a historical context. This study examined forest disturbance with regard to land use change and drought in the New River Gorge region of West Virginia. I developed a 182-year pitch pine ( Pinus rigida) growth chronology (1833-2014) using samples collected from 33 trees along 2 km of southand southwest-facing slopes at Babcock State Park. Samples cut from fire-scarred pitch and Virginia pine ( Pinus virginiana) were used to generate a fire chronology for the site. Temporal trends in pitch pine growth variability were assessed using regime shift and growth release detection methods. There was no change in pitch pine growth during the transition from the early settlement to industrial era (ca. 1885), while a significant decrease in annual growth variability characterized the post-industrial era (1963-2014). Seventeen fire events were recorded between 1887 and 1968. Growth releases displayed a temporal relationship with fire and there was a strong, but not significant, association between drought and fire years. These results suggest a coupled system in which anthropogenic fires driven by periodic drought maintained pitch pine before and during industrialization. Reintroducing fire to the post-industrial forest may not meet management objectives as decades of fire exclusion have altered forest fuels and species composition such that its effects would be difficult to predict. [ABSTRACT FROM AUTHOR]

• We assessed forest structure and composition across different pitch pine barren community types and management strategies. • Pine barrens are a landscape mosaic maintained by human and environmental disturbance regimes. • Prescribed fire, thinning, and their combination are effective in maintaining pine barrens communities. • A lack of active management may lead to a transition towards mesophytic forests. Pitch pine (Pinus rigida Mill.) barrens are a globally rare, fire-dependent ecosystem of great ecological, social, and cultural significance found primarily in the northeastern US. In many cases, fire has been excluded from these systems leading to habitat degradation and biodiversity loss as pine barrens landscapes homogenize into closed-canopy forests of shade-tolerant, mesophytic species. This study aims to support the adaptive management of pine barrens ecosystems in the face of mesophication by contributing baseline information on their structure and composition. Specifically, we (1) assessed how stand conditions differ between community types and management strategies at the two sites and (2) placed this work in the broader context of pine barrens ecology and management. We sampled overstory structure and composition across five community types (successional northern sandplain grasslands, pitch pine-scrub oak barrens, pitch pine-scrub oak thicket, pitch pine-scrub oak woodland, and pitch pine-oak forest) and four management strategies (burning, thinning, burning and thinning, and no management). Differences in structure and composition between communities supported the concept of pine barrens as a landscape mosaic maintained by multiple unique disturbance regimes. Results suggest that burning, thinning, and their combination are all effective in maintaining conditions historically associated with pine barrens communities, and that a lack of active management may lead to a transition away from these characteristics. The range of pine barrens conditions documented in this and previous studies underscores the importance of management regimes that utilize a diversity of treatments applied at frequencies and intensities consistent with historic disturbance regimes for each pitch pine community type. Such strategies would maintain the mosaic of habitat conditions required to support the suite of species endemic to these communities, and would confer resilience to emerging stressors, such as southern pine beetle (Dendroctonus frontalis), which often generates greatest impacts in unmanaged, homogeneous forests. [ABSTRACT FROM AUTHOR]

Wood samples of Pinus rigida , Juglans nigra , and Fagus sylvatica were superficially inoculated with three mold fungi ( Penicillium selerotigenum , Paecilomyces variotii , and Aspergillus niger ). The changes in wood surfaces and the elemental composition were observed by scan electron microscope (SEM) and the electron dispersive X-ray spectroscopy (EDX), respectively. Wood elemental composition was an indication of the growth of mold fungi, in which P. selerotigenum , and A. niger have consumed high amount of carbon (C) of F. sylvatica wood compared to control treatment. Also, P. selerotigenum consumed high amount of C of J. nigra wood compared to the control. While, the three mold fungi showed little changes in C content in P. rigida wood. The nitrogen element in the studied woods was completely consumed by the three mold fungi. Cl element increased in the three woods as inoculated by the three fungi compared to untreated woods. Other elements such as S, Si, Ca, Zn, Cu, and Fe varied in their content in accordance to the interaction among wood species and fungi. The growth of the three mold fungi showed distribution and structures of spores and hyphae covering deteriorated wood surfaces. The study suggests that the three mold fungi metabolize the carbon-rich constituents of the investigated wood species in a proportional manner and produce large fruiting structures that release vast numbers of spores in nature. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Variation in a species is a blend of adaptive, random, and migratory responses. Pitch pine (Pinus rigida), a highly variable eastern conifer, has occupied multiple glacial refugia, whose harsh conditions favored adaptations enhancing subsequent dispersal and recolonization of newly deglaciated sites. We assessed phenotypic diversity in long-term growth trials to elucidate both the adaptations and likely refugia. METHODS : Pitch pine progeny from 31 areas were grown in common gardens in six locations, from eastern Massachusetts to Korea. KEY RESULTS: Survival increased with source latitude, but seedlings from southern latitudes were tallest in the first (postplanting) year, but that advantage dissipated in later years. Progeny from northern latitudes were precocious, highly fecund, had smaller seeds, and more seeds per cone. Seed mass decreased with latitude in both parents and progeny. Serotinous cones were notably common in the New Jersey Pine Plains and Acadia National Park. Various disease agents and frost burn exhibited latitudinal trends that were nonlinear, with a break in the regression slope at about 40°N latitude. Cluster analysis identified both northern and southern groups, largely split between unglaciated and deglaciated terrain, but with Acadia and the Pine Plains as unique outliers. Within the southern group, provenances were organized into contiguous subgroups, but geographic structure was less evident in the northern group. CONCLUSIONS: The present range of pitch pine was colonized by migrants from at least three different refugia, including at least one on the exposed continental shelf during the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

The Panther Knob Preserve is important in the Central Appalachians because it is the region's largest high-elevation pitch pine ( Pinus rigida) community, containing numerous rare and threatened plants and animals. Plant community structure and evidence of fire in 2008 were quantified to (a) document successional changes since 1985, and (b) test the hypothesis of pitch pine regeneration failure without recent fire. Diameter at breast height (dbh) of trees and percent cover of plants within 19 plots, each 20 × 20 m, were measured. Increment borings were used to estimate stand age, and evidence of fire, such as bark charring and soil charcoal, was recorded. Mineral soil from the top 10 cm was collected to evaluate the connection between soil characteristics and plant composition. Cluster analysis of percent cover values identified four plant community types. Diameter distributions, age structure, and the presence of only seven seedlings indicated little recent pine regeneration on the plateau. Comparisons with Fleming's (1985) observations showed that pines are taller but declined in percent cover, that ericaceous shrubs are denser, and that the threatened variable sedge, Carex polymorpha, has declined. Charred woody debris, fire scars, or soil charcoal occurred at 16 of 19 sites. Plant community structure, represented by nonmetric multidimensional scaling (NMS) ordination axes, was not correlated directly with the presence of fire evidence or soil mineral nutrients (principal components analysis [PCA] axes). A new conceptual model of pine dynamics on Panther Knob is introduced. Successional pathways with and without fire are discussed in the context of management. [ABSTRACT FROM AUTHOR]

In this study, coniferous (pitch pine,Pinus rigida) and broad-leaved (Oriental oak,Quercus variabilis) trees were gasified in a bubbling fluidized bed reactor, and the effects of reaction temperature and catalyst species on product yields and selectivities were systematically investigated. Upon increasing the gasification temperature from 800 to 900°C, the gas yield ofP. rigidamaintained similar values at 75.15–78.41%, while the gas yield ofQ. variabilisdecreased from 71.05 to 58.15% and the char and oil yields increased. The composition of gaseous products was affected according to catalyst species. When dolomite-based catalysts were used for fog biomass gasification, the hydrogen fraction increased substantially, while the carbon monoxide fraction decreased. [ABSTRACT FROM PUBLISHER]

Abstract: The essential oils of the leaves of three Pinus species (Pinus densiflora, P. thunbergii, P. rigida) were analyzed by gas chromatography/mass spectrometry (GC/MS). Analysis of the oils from P. densiflora, P. thunbergii and P. rigida revealed the presence of α-humulene (18.09%, 19.59%, 14.08%), caryophyllene (7.69%, 5.32%, 10.20%), β-pinene (4.95%, 4.45%, 7.39%), β-cadinene (3.28%, 1.30%, 3.71%), cinnamic acid (2.62%, 1.24%, 2.87%), α-terpinolene (2.10%, 0.51%, 0.3%), spathulenol (2.04%, 0.34%, 2.78%), α-cadinol (1.85%, 0.97%, 2.60%), caryophyllene oxide (1.82%, 0.23%, 0.13%) and α-pinene (1.79%, 0.68%, 0.13%) as major constituents. Essential oil from P. thunbergii showed stronger inhibitory activity against Bacillus subtilis, Bacillus natto, Staphylococcus aureus, Escherichia coli, Salmonella typhosa and Pseudomonas aeruginosa than the other two Pinus species, and essential oils of the three Pinus species showed strong antimicrobial activity against Salmonella enteritidis and P. aeruginosa. The essential oils from the three Pinus species also showed higher antimicrobial activity against Gram-negative bacteria than Gram-positive bacteria. Saccharomyces cerevisiae (yeast) was not inhibited by any essential oil. [Copyright &y& Elsevier]

Premise of the study: Fire in the New Jersey Pine Plains has selectively maintained a dwarf growth form of pitch pine (Pinus rigida), which is distinct from the surrounding tall forest of the Pine Barrens and has several other inherited adaptations that enable it to survive in an environment dominated by fire. Methods: Pitch pine progeny from two Pine Plains sites, the West and East Pine Plains, were grown in common garden environments with progeny from two Pine Barrens stands. Batsto and Great Egg Harbor River. The tests were replicated in five locations: in New Jersey, Connecticut, two sites in Massachusetts, and Korea. One of the tests was monitored for up to 36 yr. Key results: Progeny of Pine Plains origin were, in general, shorter, more crooked, precocious, bore more cones, had a higher frequency of serotinous cones, and had a higher frequency of stem cones than did Pine Barrens progeny, wherever they were grown. Conclusions: The Pine Plains is an ecotype that has evolved in response to disturbance. The several characters that distinguish it from the surrounding tall forest of the Pine Barrens are inherited. The dwarf stature and crooked form not only enable the ecotype to persist in an environment of frequent fires but also increase its flammability. [ABSTRACT FROM AUTHOR]

This study compared the antimicrobial activity and total phenolic content of three Pinus plants (Pinus densiflora, P. thunbergii, P. rigida) for the first time. The antimicrobial activity of the water fraction of methanol extract of fresh leaves was stronger than that of fallen leaves at any concentrations. The water fraction of crude methanol extract from fresh leaves of P. thunbergii showed a higher growth inhibitory activity against gram-positive and gram-negative bacteria than that of P. densiflora and P. rigida. The results from the disc diffusion method followed by measurements of minimal inhibition concentration (MIC) indicate that Bacillus subtilis was the most sensitive microorganism with the lowest MIC value. The highest total phenolic content was found in fresh leaves of P. rigida and P. thunbergii. The assay showed that the fresh leaves of the three Pinus plants contained higher total phenolic content than fallen leaves of the three plants. The antimicrobial activity was related with the total phenolic content. [ABSTRACT FROM AUTHOR]