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The increase in cheese production, sale, and consumption due to the settled lives of societies has led to an increase in cheese‐related diseases. It has become essential to better understand cheese‐borne diseases and to develop control measures. In this study, cheese‐related diseases and precautions taken in the Ottoman Empire from the 19th to the 20th centuries were investigated in Ottoman archival sources. Of these documents, cheese spoilage was detected in 12 and cheese‐related disease in 9. Cheeses that caused diseases or disorders in the relevant period were called spoiled cheese. One document states that a person died of a cheese‐borne illness. Cheese poisoning occurs mainly from unsalted, fresh cheeses. It has been determined that tin‐free copper pots were used in cheese production and sales and covered with herbs such as hemlock during maturation. In the relevant period, microbiological and chemical analyses of cheeses in terms of health were carried out in food control laboratories. Since the mercury chloride solution is used to disinfect animal udders, it has been stated that it contaminates the milk used in cheese production. Authorities have requested a boric acid solution (5% boric acid in hot water) instead of this solution for udder disinfection. In the Ottoman Empire, it was requested to take necessary sanitation and hygiene measures to prevent spoilage and cheese‐related diseases in the production areas or sales places of cheese. Clean and tinned containers should be used in cheese production, storage, and sale, and poisonous herbs should not be used during cheese ripening. It was also essential to analyze them in laboratories at internal and external customs. Knowing the precautions taken in the past to prevent the deterioration of food or the occurrence of diseases has led to modern food safety practices being applied today. [ABSTRACT FROM AUTHOR]

Nuclear microsatellite markers were developed for the two Tsuga species native to the Japanese Archipelago, Tsuga diversifolia and T. sieboldii, and a population with genetic affinities to T. diversifolia on Ulleung Island, Korea. Tsuga diversifolia and T. sieboldii are widespread dominant trees of temperate and subalpine forests in Japan but to date no genetic markers have been developed for these species. Fifteen polymorphic loci were developed and characterized, of which 14 are reliably amplified in each taxon. Across both species and the Ulleung Island population, the number of alleles per locus ranged from 3 to 26 (average = 13.93) and observed heterozygosity ranged from 0.005 to 0.935 (average = 0.535). In addition, all 15 loci were successfully amplified in a single accession of the Chinese species, T. chinensis. These markers will be useful for investigating the species' biogeography, range-wide genetic diversity, conservation genetic issues and potential for hybridisation. [ABSTRACT FROM AUTHOR]

The isolated effects of a single insecticide can be difficult to assess in natural settings because of the presence of numerous pollutants in many watersheds. Imidacloprid use for suppressing hemlock woolly adelgid, Adelges tsugae (Annand) (Hemiptera: Adelgidae), in forests offers a rare opportunity to assess potential impacts on aquatic macroinvertebrates in relatively pristine landscapes. Aquatic macroinvertebrate communities were assessed in 9 streams in Great Smoky Mountains National Park (southern Appalachian Mountains, USA). The streams flow through hemlock conservation areas where imidacloprid soil drench treatments were applied for hemlock woolly adelgid suppression. Sites were located upstream and downstream of the imidacloprid treatments. Baseline species presence data (pre-imidacloprid treatment) were available from previous sample collections at downstream sites. Downstream and upstream sites did not vary in numerous community measures. Although comparisons of paired upstream and downstream sites showed differences in diversity in 7 streams, higher diversity was found more often in downstream sites. Macroinvertebrate functional feeding groups and life habits were similar between downstream and upstream sites. Downstream and baseline stream samples were similar. While some functional feeding group and life habit species richness categories varied, variations did not indicate poorer quality downstream communities. Imidacloprid treatments applied according to US Environmental Protection Agency federal restrictions did not result in negative effects to aquatic macroinvertebrate communities, which indicates that risks of imidacloprid use in forest settings are low. Environ Toxicol Chem 2017;36:3108-3119. © 2017 SETAC [ABSTRACT FROM AUTHOR]

Two of the most important resources in agriculture are soil and water. The quality of the soil determines the health and output of crops. Biochar has been recognized as being a useful soil amendment due to its perceived benefits of increasing water and nutrient retention. However, limited research has been conducted to compare the characteristics of biochar created from different feedstocks to determine which are the most effective at raising water holding capacity. This study compared the water holding capacity and chemical composition of biochar created from two different materials: eastern hemlock and switchblade grass. Results showed that both the hemlock char and switchblade grass char were able to significantly raise the water holding capacity of loamy sand. The switchblade grass increased the water holding capacity more than the hemlock biochar. For example, at a mixture rate of 10% biochar by weight, switchblade grass increased loamy sand's water holding capacity by 228%, compared with 133% for hemlock. The water holding capacity of the switchblade grass biochar alone was 448.69% of its weight and the hemlock biochar held 268.34% of its weight. These results suggest that switchblade grass may be better suited for improving water retention in sandy soils. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1474-1479, 2017 [ABSTRACT FROM AUTHOR]

Aim Predicting the migration of vegetation in response to climate change is often done using a climate-driven vegetation model; however, the assumption of full migration (where seeds are not limited by distance or barriers) is a common criticism. Previous efforts to incorporate limitations on seed dispersal have occurred exclusively in bioclimatic envelope models. This paper describes how limitations on seed dispersal were integrated into a physiologically based dynamic vegetation model, LPJ-GUESS. Location An idealized landscape, representative of temperate and boreal forests in North America. Methods LPJ-GUESS already simulates establishment, growth, reproduction and competition. I used a generic seed dispersal kernel to determine the probability of dispersal between grid cells, and a logistic function to determine the spread between patches within a grid cell. Plant functional types were parameterized to represent three temperate tree species, Acer, Pinus and Tsuga, by using published dispersal kernels and life-history measurements. Simulations were run with full and limited migration, and compared with past vegetation migration rates. Results Using the old assumption of full migration, the entire landscape was colonized at the same time (migration rates of 270-380 m year−1). With the new limited dispersal, species colonized the landscape one row at a time, at rates which corresponded well with independent migration estimates based on genetic or pollen reconstructions ( Acer, 141 m year−1; Pinus, 76 m year−1). Tsuga was the only species where simulated migration rates (85 m year−1) were quite a bit slower than historical migration estimates. Main conclusions The new model was able to simulate reasonable migration rates, which is a substantial improvement over previous assumptions of full migration. Migration estimates which include the effects of limitations on dispersal, demography, competition and plant physiology will also improve our understanding of how climate change and various other processes can influence plant range shifts. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: A 28-year-old man presented with acute flaccid paralysis and respiratory failure that persisted for 2 weeks after suicidal ingestion of unknown substances. Methods: Extensive clinical, nerve, laboratory, and neuroimaging testing excluded alternative causes of this neuromuscular syndrome. Prompted by clues provided by family members, liquid chromatography time-of-flight mass spectrometry was used to investigate for the presence of poison hemlock. Results: Testing of the residue in a jar used for the ingestion of a poisonous concoction confirmed the presence of the nicotinic alkaloid coniine. Analysis of patient serum suggested the presence of conhydrine. Concentrations of amitriptyline and diazepam were also found to be supratherapeutic, but only through the first few days of hospitalization. Conclusions: Herein we describe a case of reversible coma, flaccid quadriparesis, and neuromuscular respiratory failure caused by intentional ingestion of poison hemlock. Muscle Nerve 48:823-827, 2013 [ABSTRACT FROM AUTHOR]

ABSTRACT Vegetation canopies intercept and redistribute precipitation in space. Although throughfall patterns are challenging to correlate with plant characteristics, many studies have shown that the spatial patterns persist through time. This persistence leads to wet and dry spots that can affect recharge, transpiration, and other nonlinear ecohydrologic and biogeochemical processes. A stochastic framework is used to determine the effect of throughfall variability on hydrologic fluxes. Throughfall variability increases and concentrates recharge, and the magnitude of the effect depends on the character of throughfall variability along with characteristics of climate, soil, and vegetation. This framework is also used to explore specific differences in summertime recharge between stands of deciduous trees (birch, maple, and oak) and eastern hemlock ( Tsuga canadensis). Throughout the eastern United States, the invasive hemlock woolly adelgid poses a significant threat to hemlock forests, and replacement of hemlock forests by other species has the potential to alter hydrologic fluxes and other processes. Field investigations in 2009 and 2010 indicate that, relative to deciduous stands, hemlock canopies intercept more water and tend to produce dry rather than wet spots. Although deciduous stands produce more throughfall, model results indicate that differences in canopy interception are outweighed by large differences in peak transpiration rates, and predictions of summertime recharge are lower in deciduous forests than in hemlock. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We describe the isolation and characterization of 31 polymorphic di- and trinucleotide microsatellite marker loci for Carolina hemlock ( Tsuga caroliniana Englem.). In addition, primer pairs for 16 loci amplified scoreable alleles in six other Tsuga species. In eastern North America, both Carolina hemlock and eastern hemlock ( Tsuga canadensis [L.] Carr.) populations are declining due to infestation by hemlock woolly adelgid, Adelges tsugae. The markers described here should enhance population genetic studies of hemlocks, providing valuable information for conserving and restoring these important forest tree species. [ABSTRACT FROM AUTHOR]

One unexpected consequence of natural disturbances in forested areas is that managers often initiate activities that may impose greater ecosystem impacts than the disturbances themselves. By salvage logging areas affected by windstorms or other impacts, by harvesting host trees in advance of insect infestation or disease, or by preemptively harvesting forests in an attempt to improve their resilience to future disturbances and stresses, managers initiate substantial changes in the ecosystem structure and function. Much of this activity is undertaken in the absence of information on the qualitative and quantitative differences between disturbance impacts and harvesting. To provide insight for such decisions we evaluated the ecosystem consequences of two major disturbance processes in New England (U.S.A.)—intense windstorms and invasive pests and pathogens—and contrasted them with impacts from preemptive and salvage harvesting. Despite dramatic physical changes in forest structure resulting from hurricane impacts and insect infestation, little disruption of biogeochemical processes or other ecosystem functions typically follows these disturbances. Indeed, the physical and organic structures produced by these disturbances are important natural features providing habitat and landscape heterogeneity that are often missing due to centuries of land use. From an ecosystem perspective there are strong arguments against preemptive and salvage logging or the attempt through silvicultural means to improve the resistance or resilience of forests to disturbance and stress. There are often valid motivations for salvage or preemptive logging including financial considerations, human safety, and a desire to shape the long-term composition and resource-production characteristics of forests. Nonetheless, there are many ecological benefits derived from leaving forests alone when they are affected or threatened by disturbances and pest and pathogen outbreaks. [ABSTRACT FROM AUTHOR]

Reproducibility of vegetation measurements is critical for large-scale or long-term studies, where numerous observers collect data,but past studies have questioned reproducibility of some techniques. Five methods of evaluating understory composition were appraised for reproducibility among six observers in two forest types in south-central Alaska: ocular estimates in quadrats, overall community species rank and cover estimates, nested rooted frequency, horizontal-vertical profiles, and pin drop (systematic points). One forest type was selected to represent structure of coastal communities, another to represent structure of interior Alaska communities. Three general methods of evaluating reproducibility were considered: standard deviations (precision among observers), components of variance (percentage of total variance attributable to observers), and analysis of variance (significance of observer variance). Observer variances were generally similar among techniques and significant in most cases. No technique stood out as being more reproducible than others. Features of techniques other than reproducibility may be more important when selecting a technique. Management decisions based on vegetation cover data should consider the observer errors involved as well as biological significance. [ABSTRACT FROM AUTHOR]

Abstract Aim Despite decades of study we have limited insights into the nature of the pre-European landscape of the north-eastern USA and the forces and changes that shaped modern forest patterns. Information on such long-term forest dynamics would provide critical insights into the relationships among environmental change, land-use history and biotic responses and is greatly needed for conservation planning. To address these issues we used modern, historical, and palaeoecological approaches to reconstruct the 3500-year history of a New England upland region dominated by oak and (formerly) chestnut forests and to interpret the interactions among climate change, natural and human disturbance, and site factors in controlling vegetation patterns and dynamics at different spatial scales. Location The study focused on a broad upland ridge dominated by oak forests in the north-central Massachusetts town of New Salem. Detailed palaeoecological analyses were undertaken of wetland (Chamberlain Swamp) and lake (Lily Pond) basins in order to reconstruct local to regional scale vegetation dynamics, which were interpreted within the context of regional vegetation data from central Massachusetts. Methods Palaeoecological methods were used to reconstruct the vegetation, fire and land-use history of the local and subregional vegetation from the two basins and to place these in the context of regional information on vegetation and climate change based on other published data. Historical information including maps, archaeological and census data, and vegetation information were gathered for the landscape and areas surrounding the coring sites. Vegetation sampling in transects adjacent to the swamp coring area included tree cores for dendrochronological reconstructions. Results Stand, landscape and regional forest dynamics were most strongly driven by climate, notably an apparent cooling and increase in moisture availability c. 1500 yr bp, and European land-use activities... [ABSTRACT FROM AUTHOR]

Discusses the ecological changes brought about by the infestation of crops by exotic pathogens and pests. Changes in forest dynamics; Impact of the introduction and spread of fungal disease chestnut blight in North America; Ecological impact of the infestation of the hemlock woolly adelgid in New England.

Barrier zones are formed not only in response to mechanical wounds, but in response to interactions by microorganisms. The zones are an important non-specific response to various kinds of injuries and infectious. The response of large conifer roots to drill wounds resulted in compartmentalization of xylem and localization of bark lesions close to the wounds. Bands of resin ducts differentiated in the xylem and necrophylactic periderms confined the areas of dead bark around the wounds. Sections through the drill wounds made in balsam fir and hemlock roots show a record of cambial activity over the two years between wounding and harvest. The barrier zones of resin ducts were extensive when internal discoloration or decay was obvious in the roots. A drill wound alone did not initiate extensive bands of duets. Bands of ducts extended tip to 20 mm from the drill wounds in samples where no curl of callus and xylem had formed around the edge of the wound. When microorganisms had invaded the tissues in the vicinity of the wound, it was common that more than one ring of ducts formed. The cambium responded repeatedly if aggravated by infections, resulting in multiple bands of ducts. [ABSTRACT FROM AUTHOR]

Polymorphic microsatellite loci were developed for Western Hemlock [ Tsuga heterophylla (Raf.) Sarg], a prominent forest tree species in Western North America. Microsatellite-enriched libraries were screened for (CA) n dinucleotide repeats from which 33 positive clones were sequenced. Polymerase chain reaction (PCR) primers for 16 microsatellite loci were prepared and tested against DNA from unrelated Western Hemlock trees. The 12 most informative microsatellite loci are reported here. From four to 22 alleles per locus were observed, with an average expected heterozygousity of 0.799. [ABSTRACT FROM AUTHOR]

The hemlock woolly adelgid (HWA) is an insect native to Asia and likely western North America. First reported in eastern North America in 1951, it has devastated eastern hemlock (Tsuga canadensis) populations. Loss of hemlock will greatly affect the structure and function of eastern forests. Susceptibility to adelgid infestation varies within eastern hemlocks and across other hemlock species. Our study was conducted to determine whether eastern hemlocks share a similar stem (phyllosphere) microbial community with other co‐occurring hemlocks and whether community‐level shifts are associated within trees of the same species based on HWA infestation. Surprisingly, we found no difference in microbial community composition or diversity between trees of the same species based on the level of HWA infestation. However, microbial communities varied significantly across the four hemlock trees sampled, native T. canadensis and three non‐natives: Tsuga chinensis, Tsuga dumosa, and Tsuga sieboldii. Within these tree hosts, microbial communities from T. dumosa and T. chinensis clustered together, and microbial communities from T. canadensis and T. sieboldii clustered separately from all other tree species. Additionally, specific indicator taxa were identified for all the tree species sampled. These results indicate that Asian hemlocks might not fill the same niche in eastern forests as the native eastern hemlock. Further work should be conducted to determine how differences in hemlock species and associated microbial communities might scale up to alter organismal interactions involving hemlocks. [ABSTRACT FROM AUTHOR]

The post—glacial history of two adjacent sites in the Harvard Forest, a 10—ha swamp (Black Gum Swamp) and a 0.006—ha hollow (Hemlock Hollow) in a Tsuga canadensis forest were investigated using pollen analysis. The sites were selected in order to contrast the regional vegetation history revealed from the swamp sediments with the local history of the Tsuga forest reconstructed from the Hollow sediments. Specific objective were (1) to document the natural and anthropogenic disturbance history, (2) to examine the long—term vegetation dynamics of the two sites resulting from environmental change, species migration, and disturbance, especially with respect to Tsuga, and (3) to contrast the pre— and post—settlement vegetation and environments. The Swamp and Hollow cores contain continuous sediment records covering the past 12 300 and 9500 yr, respectively. Regional vegetation changes are delimited in six pollen zones: I, Herb zone (12 500—11 800 yr BP); II, Picea zone (11 800—9500 yr BP); III, Pinus—Quercus zone (9350—8350 yr BP); IV, Tsuga—northern hardwoods zone (8350—1750 yr BP); V, Tsuga—Castanea—hardwoods zone (1750—200 yr BP); and, VI Post—settlement zone (200 yr BP—present). No disturbances are detected in the periods of tundra or boreal vegetation from 12 500 to 8 350 yr BP. Since 8350 yr BP three distinct disturbance processes are detectable: (1) fires recorded in discrete charcoal horizons, (2) the apparent pathogenic decline of Tsuga (4700—3500 yr BP) and the blight of Castanea (° 1915 A.D.), and (3) post—settlement forest cutting, burning, land clearance, and cultivation (1750 A.D. to present). Log—ratio diagrams facilitate the differentiation of local vegetation history in the Tsuga forest from the regional upland history. Tsuga has been the dominant taxon at the Hollow for the last 8000 yr although its abundance has fluctuated with disturbance. Tsuga, Ulmus, Populus, Acer rubrum, A. saccharum, Betula, and Castanea apparently are more abundant locally than in the regional vegetation, which has a larger component of Pinus, Quercus, and Carya. Post—disturbance vegetation dynamics in the Tsuga forest are controlled by the type and intensity of disturbance and the pool of available species, determined by species migration and climate change. Tsuga decreases and subsequently recovers in 300—1200 yr following most disturbances. Northern hardwood taxa (Acer saccharum, Fagus, Betula spp., Ulmus, Fraxinus) generally decrease after fire and human activity and recover with Tsuga. For the period 8000—3000 yr BP Pinus, Quercus, and occasionally Populus and Nyssa increase following fire and the Tsuga decline at 4700 yr BP. However, since its immigration at °3000 yr BP Castanea has been the major species to increase upon disturbance of the Tsuga—northern hardwood forest. The study documents the long—term dominance of a forest stand by Tsuga canadensis and northern hardwood species despite repeated infrequent disturbances. The ability of these taxa to gradually reassume their former abundance following disturbance is presumably a consequence of their shade tolerance and longevity and the low frequency of disturbance., Organismic and Evolutionary Biology