Journal articles: 'North American trees'

1

Schmid, Rudolf, and Arthur Lee Jacobson. "North American Landscape Trees." Taxon 45, no. 3 (1996): 580. http://dx.doi.org/10.2307/1224175.

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Pregitzer, Kurt S., Jared L. DeForest, Andrew J. Burton, Michael F. Allen, Roger W. Ruess, and Ronald L. Hendrick. "FINE ROOT ARCHITECTURE OF NINE NORTH AMERICAN TREES." Ecological Monographs 72, no. 2 (2002): 293–309. http://dx.doi.org/10.1890/0012-9615(2002)072[0293:fraonn]2.0.co;2.

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Hollingsworth, Phillip R., and C. Darrin Hulsey. "Reconciling gene trees of eastern North American minnows." Molecular Phylogenetics and Evolution 61, no. 1 (2011): 149–56. http://dx.doi.org/10.1016/j.ympev.2011.05.020.

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Hemmerly, Thomas E. "The living earth book of North American trees." Economic Botany 48, no. 1 (1994): 75. http://dx.doi.org/10.1007/bf02901384.

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Kawa, Nicholas C., Bradley Painter, and Cailín E. Murray. "Trail Trees: Living Artifacts (Vivifacts) of Eastern North America." Ethnobiology Letters 6, no. 1 (2015): 183–88. http://dx.doi.org/10.14237/ebl.6.1.2015.410.

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Living trees historically modified by human populations, oftentimes referred to as “culturally modified trees” (CMTs), are found throughout the North American landscape. In eastern North America specifically, indigenous populations bent thousands of trees to mark trails, and some of these still exist in the region today. In this article, we present a synthesis of current knowledge on trail trees, including their speculated functions, formation, and selection. We also examine the theoretical implications of these living artifacts (or vivifacts) and how they may open new avenues for investigation by archaeologists, environmental historians, and ethnobiologists. To conclude, we make a call for expanded public recognition and documentation of trail trees, discussing the need for their incorporation into forest and park management plans.

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Schlachter, Kyle J. "Range Shape and Range Elongation of North American Trees." Physical Geography 31, no. 1 (2010): 40–57. http://dx.doi.org/10.2747/0272-3646.31.1.40.

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Xing, Dingliang, Nathan G. Swenson, Michael D. Weiser, and Zhanqing Hao. "Determinants of species abundance for eastern North American trees." Global Ecology and Biogeography 23, no. 8 (2014): 903–11. http://dx.doi.org/10.1111/geb.12167.

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Morin, Xavier, and Martin J. Lechowicz. "Niche breadth and range area in North American trees." Ecography 36, no. 3 (2012): 300–312. http://dx.doi.org/10.1111/j.1600-0587.2012.07340.x.

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Navar, Jose, Felipa de Jesus Rodriguez-Flores, and Julio Rios-Saucedo. "Biomass estimation equations for mesquite trees in the Americas." PeerJ 7 (April 25, 2019): e6782. http://dx.doi.org/10.7717/peerj.6782.

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Mesquite trees are the preferred dendroenergy sources in arid and semi-arid forests. In spite of their relative importance, regional aboveground biomass (AGB) equations for mesquite trees are scarce in the scientific literature. For that reason, the aims of this study were to: (a) harvest trees and develop regional biomass equations; (b) contrast measured data with equations developed previously; and (c) test the applicability of the fitted equation for mesquite trees in the arid and semi-arid forests of the Americas. We harvested 206 new mesquite trees from arid and semi-arid forests in northern Mexico (Coahuila, Nuevo Leon, and Tamaulipas) in addition to using two other previously compiled data sets from Mexico (N = 304) to develop a regional equation. To test the validity of this equation, for biomass equations reported for the rest of the country, as well as for North and South American mesquite trees, we contrasted AGB measurements with predictions of fitted equations. Statistical analysis revealed the need for a single, regional, semi-empirical equation as together the three data sets represented the variability of the aboveground biomass of mesquite trees across northern Mexico, as well as mesquite trees in America’s arid and semiarid regions. Due to the large quantity of mesquite trees harvested for sampling and their variability, the regional biomass equation developed encompasses all other North and South American equations, and is representative of mesquite trees throughout the arid and semi-arid forests of the Americas.

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Asbeck, T., M. Basile, J. Stitt, J. Bauhus, I. Storch, and K. T. Vierling. "Tree-related microhabitats are similar in mountain forests of Europe and North America and their occurrence may be explained by tree functional groups." Trees 34, no. 6 (2020): 1453–66. http://dx.doi.org/10.1007/s00468-020-02017-3.

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Abstract Key message Drivers of the abundance and richness of tree-related microhabitats are similar in mountain forests of Europe and North America and their occurrence may be explained by tree functional groups. Abstract A common approach to support forest-dwelling species in managed forests is to preserve valuable habitat trees. To assess the quality of habitat trees, a hierarchical typology of tree-related microhabitats (TreMs) is applied in the European context for inventory standardization. The first aim of this study was to evaluate whether it is possible to use this hierarchical typology as a standard protocol regardless of location, which is important for potentially standardizing future studies of TreMs, by testing whether the typology could be applied to the western North American mountain forests of Idaho. The second aim of the study was to analyse drivers that influence TreMs in forests of the region. Thirdly, we assessed whether the occurrence of TreMs could be explained by functional groups of trees across the western mountain forests of Idaho and Central European mountain forests, using TreM inventory data previously collected in the Black Forest, Germany. Abundance and richness of TreMs per tree were analyzed as a function of tree species, live status (dead vs. live trees), diameter at breast height (DBH), and site factors (latitude and altitude). Our results show that the TreM typology could be applied with slight modifications in the forests of Idaho. The abundance and richness of TreMs per tree increased with DBH. Snags offered more TreMs per tree than live trees. We were able to group tree species from the two continents in functional groups that were related to the occurrence of certain TreMs. Tree functional groups offer an opportunity to predict the role of certain tree species for habitat provision through TreMs. Combinations of trees from different functional groups could be used to optimize provisioning of TreMs within forest stands.

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11

Hu, L., D. B. Millet, S. Y. Kim, et al. "North American acetone sources determined from tall tower measurements and inverse modelling." Atmospheric Chemistry and Physics Discussions 12, no. 11 (2012): 30869–908. http://dx.doi.org/10.5194/acpd-12-30869-2012.

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Abstract. We apply a full year of continuous atmospheric acetone measurements from the University of Minnesota tall tower Trace Gas Observatory (KCMP tall tower; 244 m a.g.l.), with a 0.5° × 0.667° GEOS-Chem nested grid simulation to develop quantitative new constraints on seasonal acetone sources over North America, and assess the corresponding impacts on atmospheric chemistry. Biogenic acetone emissions in the model are computed based on the MEGANv2.1 inventory. An inverse analysis of the tall tower observations implies a 37% underestimate of emissions from broadleaf trees, shrubs, and herbaceous plants, and an offsetting 40% overestimate of emissions from needleleaf trees plus secondary production from biogenic precursors. The overall result is a small (16%) model underestimate of the total primary + secondary biogenic acetone source in North America. Our analysis shows that North American primary + secondary anthropogenic acetone sources in the model (based on the EPA NEI 2005 inventory) are accurate to within approximately 20%. An optimized GEOS-Chem simulation incorporating the above findings captures 70% of the variance (R=0.83) in the hourly measurements at the KCMP tall tower, with minimal bias. The resulting North American acetone source is 10.9 Tg a−1, including both primary emissions (5.5 Tg a−1) and secondary production (5.5 Tg a−1), and with roughly equal contributions from anthropogenic and biogenic sources. The North American acetone source alone is nearly as large as the total continental volatile organic compound (VOC) source from fossil fuel combustion. Using our optimized source estimates as a baseline, we evaluate the atmospheric impact of some potential future shifts in acetone sources over North America. Increased biogenic acetone emissions due to surface warming are likely to provide a significant offset to any future decrease in anthropogenic acetone emissions, particularly during summer.

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Hu, L., D. B. Millet, S. Y. Kim, et al. "North American acetone sources determined from tall tower measurements and inverse modeling." Atmospheric Chemistry and Physics 13, no. 6 (2013): 3379–92. http://dx.doi.org/10.5194/acp-13-3379-2013.

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Abstract. We apply a full year of continuous atmospheric acetone measurements from the University of Minnesota tall tower Trace Gas Observatory (KCMP tall tower; 244 m a.g.l.), with a 0.5° × 0.667° GEOS-Chem nested grid simulation to develop quantitative new constraints on seasonal acetone sources over North America. Biogenic acetone emissions in the model are computed based on the MEGANv2.1 inventory. An inverse analysis of the tall tower observations implies a 37% underestimate of emissions from broadleaf trees, shrubs, and herbaceous plants, and an offsetting 40% overestimate of emissions from needleleaf trees plus secondary production from biogenic precursors. The overall result is a small (16%) model underestimate of the total primary + secondary biogenic acetone source in North America. Our analysis shows that North American primary + secondary anthropogenic acetone sources in the model (based on the EPA NEI 2005 inventory) are accurate to within approximately 20%. An optimized GEOS-Chem simulation incorporating the above findings captures 70% of the variance (R = 0.83) in the hourly measurements at the KCMP tall tower, with minimal bias. The resulting North American acetone source is 11 Tg a−1, including both primary emissions (5.5 Tg a−1) and secondary production (5.5 Tg a−1), and with roughly equal contributions from anthropogenic and biogenic sources. The North American acetone source alone is nearly as large as the total continental volatile organic compound (VOC) source from fossil fuel combustion. Using our optimized source estimates as a baseline, we evaluate the sensitivity of atmospheric acetone and peroxyacetyl nitrate (PAN) to shifts in natural and anthropogenic acetone sources over North America. Increased biogenic acetone emissions due to surface warming are likely to provide a significant offset to any future decrease in anthropogenic acetone emissions, particularly during summer.

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Nathan, Ran, Nir Horvitz, Yanping He, Anna Kuparinen, Frank M. Schurr, and Gabriel G. Katul. "Spread of North American wind-dispersed trees in future environments." Ecology Letters 14, no. 3 (2011): 211–19. http://dx.doi.org/10.1111/j.1461-0248.2010.01573.x.

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Abdullina, R. G. "NORTH-AMERICAN SPECIES OF ROWAN TREES FROM THE COLLECTION OF THE SOUTH-URAL BOTANICAL GARDEN." Ekosistemy, no. 22 (2020): 66–71. http://dx.doi.org/10.37279/2414-4738-2020-22-66-71.

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A brief description of three North-American species of rowan trees from the collection of the South-Ural Botanical Garden-Institute of Ufa Federal Research Centre of Russian Academy of Sciences (UFRC RAS): Sorbus decora, Sorbus americana and Sorbus scopulina is given. The climatic conditions of introduction area are similar in temperature to the parameters of the natural range of the North American S. decora: they are not optimal for it, but the plants bloom and give viable seeds. It can be assumed that vital signs of S. decora would be higher in milder climate and favorable water-physical soil conditions. According to the analysis of variance, it is revealed that the conditions of the year and species characteristics significantly affect all the phenological phases of development of North American rowan trees. At the same time, they are more dependent on the temperature conditions of the year (F=17.4 at p<0.001) and less on species characteristics (F=6.2, at p<0.001), although the sequence of phenophases is maintained from year to year. The average vegetation period of rowan trees is 154–163 days. S. decora growing in the Botanical Garden for a long time (planted in 1960–1974) and relatively new species for the collection – S. mericana and S. scopulina (2009–2013) can be considered promising decorative crops for growing in the climatic conditions of Ufa and the Bashkir Urals

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Kremer, D., J. Čavlović, and I. Anić. "The characteristics of diameter growth and increment of introduced North American ash species at the sites of common alder." Journal of Forest Science 51, No. 6 (2012): 237–43. http://dx.doi.org/10.17221/4559-jfs.

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Research was conducted into diameter growth and increment of introduced American ash species at the sites of common alder (Alnus glutinosa[L.] Gaertn.) in three mixed stands of introduced ash and common alder in the lowland part of Croatia. About 10 samples of increment cores of each species were taken from trees in the diameter class of the mean basal area. In the process, an attempt was made to reach the centre of the trees with the purpose of getting an insight into the development of the trees over a long period, i.e. from the moment when the trees reached breast height. The increment cores were analysed by measuring the width of each individual ring to the tenth of the millimetre. Bark thickness was also measured. The results obtained from the analysis of the increment cores yielded trends of ring widths for individual trees as well as trends of the average ring widths for each species within a locality. On the basis of the increment core analysis, parts of the diameter growth curve of the mean stand tree were obtained. The increment curve of mean stand diameter was obtained by deriving the growth curve of mean stand diameter. Introduced ash was found to have average ring widths from 0.92 to 4.21 mm. The measured minimal and maximal values of ring widths in total were 0.2 and 6.5 mm, respectively. Consequently, introduced ash may have significantly large ring widths in conditions of prolonged flooding as well. Therefore, its pioneering role is not irrelevant at poor sites naturally inhabited by common alder. The average ring width of introduced ash is the highest up to the age of 30 years, after which it retains the value of 2 mm or less. In common alder, the average ring width in the studied stand ranged from 1.40 to 4.59 mm. The measured minimal and maximal values of ring widths in total were 0.4 and 7.0 mm, respectively. A comparison of average ring widths of introduced ash and common alder revealed that in Draganić locality common alder had a statistically significantly larger average ring width than introduced ash. In the localities Karlovac and Đurđevac the difference was not statistically significant.

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Marek, Paul E., and David H. Kavanaugh. "The evolutionary relationships of North American Diplous Motschulsky (Coleoptera:Carabidae:Patrobini) inferred from morphological and molecular evidence." Invertebrate Systematics 19, no. 2 (2005): 145. http://dx.doi.org/10.1071/is04011.

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Individuals of the ground beetle genus Diplous Motschulsky, 1850 occur in riparian areas predominately throughout boreal North America and Asia. In order to infer the species phylogeny of the North American Diplous, we examined 97 morphological characters (56 quantitative characters and 41 qualitative characters) and 458 bp of the mitochondrial cytochrome oxidase subunit I region. We used the four North American species, four Palearctic species, and one undescribed species of a closely related genus to test the monophyly and the direction of character state change in North American Diplous. Overall, we found that North American Diplous appear to represent a monophyletic group, but that the morphological and molecular evidence did not support the same relationships in the placement of one of the species. We found that the total evidence trees agreed most with biogeography and considerations of accelerated morphological evolution. In this paper, we present a morphological phylogenetic tree, a molecular phylogenetic tree, a total evidence phylogenetic tree, a species key, species diagnoses, and a distribution map of Nearctic Diplous.

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Brydon-Williams, Rhys, I. A. Munck, and H. Asbjornsen. "Incidence and ecology of the chaga fungus (Inonotus obliquus) in hardwood New England – Acadian forests." Canadian Journal of Forest Research 51, no. 1 (2021): 122–31. http://dx.doi.org/10.1139/cjfr-2020-0144.

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Inonotus obliquus (Ach. ex Pers.) Pilát is a fungal pathogen of birch trees (Betula spp.) and other hardwoods that produces a sterile conk known colloquially as chaga. Chaga has medicinal value as an anti-mutagen and for gastro-peptic relief. Chaga harvesting has recently increased throughout its natural range in North America, including the White Mountain National Forest (WMNF). There is currently a lack of knowledge on chaga resource incidence and ecology in North America, which this project sought to rectify. Two surveys were conducted in 2017 and 2018 in the WMNF, totaling 2611 sampled trees. Positive correlations were found between chaga presence and mean stand tree age, diameter at breast height, and elevation. Overall chaga frequency was low (3.75%); however, sclerotia were widely distributed throughout the study area, with infected trees clustering. Chaga presence did not correlate with stand-level species composition or annual basal area increment, though it did appear with significantly greater frequency in yellow birch trees compared with other birch species. Additional damages related to biotic and abiotic stressors did not correlate with chaga presence, except for those resulting directly from chaga presence. These results have important silvicultural and forest management implications for chaga harvest practices across its North American range.

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Taylor, Anthony R., Donnie A. McPhee, and Judy A. Loo. "Incidence of beech bark disease resistance in the eastern Acadian forest of North America." Forestry Chronicle 89, no. 05 (2013): 690–95. http://dx.doi.org/10.5558/tfc2013-122.

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Beech bark disease (BBD) is a fatal affliction of American beech (Fagus grandifolia Ehrh.) in North America. Although natural resistance to BBD has been observed, reports vary with respect to incidence of resistance, with 1% being most commonly acknowledged. In this paper, we provide the first formal, empirical estimate of BBD resistance over a wide geographical area where BBD has been prevalent for longest in North America. We conducted our study in the Acadian Forest region of eastern Canada. Thirty-five beech-dominated stands (>5 ha each) were surveyed across the provinces of New Brunswick, Nova Scotia, and Prince Edward Island, spanning a time since infection (TSI) period between 1890 and 1975. Stands were surveyed for incidence of disease-free beech trees, which was used as a proxy for BBD resistance. Across our study area, the average percentage of disease-free trees observed was 3.3%; however, the occurrence of disease-free trees varied significantly geographically, with the oldest, most southerly TSI zone indicating 2.2% and the youngest, most northerly TSI zone showing 5.7%. Although geographic variation of disease-free beech trees may reflect disease exposure time, we speculate that lower minimum winter temperatures, combined with less intensive land-use history are the underlying mechanisms that explain the higher observed percentage of disease-free trees in the most northerly TSI zones.

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Murphy, Helen T., Jeremy VanDerWal, and Jon Lovett-Doust. "Distribution of abundance across the range in eastern North American trees." Global Ecology and Biogeography 15, no. 1 (2006): 63–71. http://dx.doi.org/10.1111/j.1466-822x.2006.00194.x.

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Morin, Xavier, and Martin J. Lechowicz. "Geographical and ecological patterns of range size in North American trees." Ecography 34, no. 5 (2011): 738–50. http://dx.doi.org/10.1111/j.1600-0587.2010.06854.x.

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Murphy, Helen T., Jeremy VanDerWal, and Jon Lovett-Doust. "Signatures of range expansion and erosion in eastern North American trees." Ecology Letters 13, no. 10 (2010): 1233–44. http://dx.doi.org/10.1111/j.1461-0248.2010.01526.x.

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O’Connell, Kyle A., and Eric N. Smith. "New molecular sequence data and species trees for North American whipsnakes." Data in Brief 18 (June 2018): 1995–99. http://dx.doi.org/10.1016/j.dib.2018.04.067.

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Glawe, Dean A. "First Report of Powdery Mildew of Platanus occidentalis caused by Microsphaera platani (Erysiphe platani) in Washington State." Plant Health Progress 4, no. 1 (2003): 33. http://dx.doi.org/10.1094/php-2003-0818-01-hn.

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American sycamore (Platanus occidentalis L.) is a common native species in eastern North America and is planted widely as a landscape tree in other regions. During a survey of powdery mildew diseases in Washington State, the fungus Microsphaera platani Howe was found on American sycamore trees in Madison Park, Seattle. This report documents the presence of M. platani in Washington State and presents information on the fungus. Accepted for publication 30 July 2003. Published 18 August 2003.

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Underwood, Lucien M. "Descriptive Catalog of the North American Hepaticae, North of Mexico." Illinois Natural History Survey Bulletin 2, no. 1-8 (2019): 1–134. http://dx.doi.org/10.21900/j.inhs.v2.84.

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The Hepaticae include quite diverse forms of vegetation, judging from the outward habit of the plants composing the group, yet all are more or less intimately related in their essential, that is. their reproductive characters. The lower forms consist of a mere expansion of tissue with no differentiation of stem and leaves. These thalloid forms are quite frequently confused with certain forms of lichens, but can be easily distinguished by the fact that while the lichen is usually rather dry and crustaceous or leathery, the hepatic is more loosely cellular or spongy in texture, and presents a moist or somewhat juicy appearance under pressure. Some of the aquatic forms have also been mistaken for algae. The higher forms of Hepaticae are more moss-like in general appearance, consisting of a stem and leaves usually closely creeping over some substance, which may be the ground itself, rotten wood, living trees, or rocks. These higher forms are sometimes confused with the true mosses (Musci), but can usually be distinguished by having the leaves two-ranked, while the mosses proper have them in several or many ranks. The more technical differences will be made apparent at a later paragraph.

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EDWARDS, DALE D., MALCOLM F. VIDRINE, and BRIAN R. ERNSTING. "Phylogenetic relationships among Unionicola (Acari: Unionicolidae) mussel-mites of North America based on mitochondrial cytochrome oxidase I sequences." Zootaxa 2537, no. 1 (2010): 47. http://dx.doi.org/10.11646/zootaxa.2537.1.4.

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Water mites of the genus Unionicola Haldeman, 1842 are common symbionts of molluscs, living on the gills or mantle and foot of their hosts and using these tissues as sites of oviposition. Phylogenetic relationships among species that comprise the genus are poorly understood and what is known has been based on a limited number of morphological and life history characters or molecular sequence data using closely-related taxa. The present study uses sequence data from the cytochrome oxidase subunit I (cox1) gene (664 bp) to reconstruct evolutionary relationships among representative species of North American Unionicola from eight subgenera that occur in symbiotic association with freshwater mussels. Maximum parsimony and maximum likelihood analysis yielded trees with similar topologies, and most of the branches have moderate to high bootstrap support. The topologies of these gene trees are mostly congruent with a previously published morphologically-derived tree. Specifically, the gene trees support monophyly among mites from subgenera that occur in association with the gill tissues of host mussels. The molecular trees of Unionicola mites generated by this study must, however, be interpreted with caution, given that the analysis is based exclusively on Unionicola subgenera from North America. A more robust phylogeny of Unionicola mussel-mites will require the addition of molecular sequence data from taxa outside of North America.

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Sinclair, W. A., A. M. Townsend, H. M. Griffiths, and T. H. Whitlow. "Responses of Six Eurasian Ulmus Cultivars to a North American Elm Yellows Phytoplasma." Plant Disease 84, no. 12 (2000): 1266–70. http://dx.doi.org/10.1094/pdis.2000.84.12.1266.

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Elms (genus Ulmus) of six clonal cultivars representing Eurasian species and hybrids were grafted when 2 to 3 years old with bark patches from U. rubra infected with an elm yellows phytoplasma or were left untreated as controls. The cultivars were U. glabra × minor ‘Pioneer’, U. minor × parvifolia ‘Frontier’, U. parvifolia ‘Pathfinder’, U. wilsoniana ‘Prospector’, and the complex hybrids ‘Homestead’ and ‘Patriot’. Trees were evaluated for infection and symptoms 1 or 2 years after inoculation. Infection was detected via the 4′,6-diamidino-2-phenylindol e·2HCl (DAPI) fluorescence test in 26 of 86 grafted trees representing five cultivars. Infection of selected trees was confirmed by polymerase chain reaction (PCR) amplification of a fragment of phytoplasmal rDNA, and the phytoplasma was identified by restriction fragment length polymorphism (RFLP) analysis of the amplified DNA using restriction enzymes AluI, RsaI, and TaqI. Elm yellows phytoplasma was also identified by nested PCR and RFLP analysis in two of seven inoculated, healthy-appearing, DAPI-negative trees and one noninoculated control tree. All RFLP profiles were identical to that of reference strain EY1. Phytoplasma-associated symptoms, observed in five cultivars, included suppressed growth, progressive size reduction of apical shoots and leaves, chlorosis, foliar reddening, witches'-brooms, and dieback. Phyto-plasma was not detected in cv. Homestead. Possible resistance of this cultivar to elm yellows phytoplasma was indicated by localized phloem necrosis in stems below inoculum patches.

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Butler, B. W., B. W. Webb, D. Jimenez, J. A. Reardon, and J. L. Jones. "Thermally induced bark swelling in four North American tree species." Canadian Journal of Forest Research 35, no. 2 (2005): 452–60. http://dx.doi.org/10.1139/x04-194.

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Bark protects both the living phloem and the vascular cambium of trees. For some tree species the bark has been observed to swell in the radial direction when heated by nearby flames, possibly providing additional protection from thermal injury. In this study, detailed measurements of bark swelling (tumescence) are reported for four species: Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), ponderosa pine (Pinus ponderosa Dougl. ex Laws.), chestnut oak (Quercus prinus L.), and red maple (Acer rubrum L.). Tests were conducted on over 574 samples extracted from 44 separate trees. The results clearly show that bark swelling occurs in the mature bark of Douglas-fir and to a lesser degree in chestnut oak. Ponderosa pine and red maple did not exhibit statistically significant swelling, but rather a modest decrease in overall bark thickness with heating. Significant swelling in Douglas-fir bark began at approximately 125 °C and resulted in a 15%80% increase in overall bark thickness. Swelling of chestnut oak was observed to begin at an average temperature of 225 °C and resulted in a 5%10% increase in total bark thickness. The increase in bark thickness occurred primarily in the radial direction in mature bark.

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Boraks, A., and K. D. Broders. "Butternut (Juglans cinerea) health, hybridization, and recruitment in the northeastern United States." Canadian Journal of Forest Research 44, no. 10 (2014): 1244–52. http://dx.doi.org/10.1139/cjfr-2014-0166.

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Butternut (Juglans cinerea L.) trees are being extirpated from their natural range by an epidemic caused by a fungal pathogen. Widespread mortality is reminiscent of past epidemics on American chestnut (Castanea dentata (Marsh.) Borkh.) and American elm (Ulmus americana L.). Butternut has remained relatively understudied, resulting in unsampled areas and gaps in our understanding of this forest epidemic and the future outlook of this species in North America. The previously unsampled area consisting of the northeastern United States was surveyed for the presence of J. cinerea, and several population health metrics were recorded, including recruitment, disease pressure, and hybridization. A total of 252 butternut trees were sampled. Analysis indicates that there is insufficient J. cinerea recruitment to maintain population sizes. Further compounding low recruitment, butternut saplings demonstrate elevated levels of disease impact from the fungal pathogen Ophiognomonia clavigignenti-juglandacearum Broders & Boland. Natural hybridization of butternut with introduced congenics such as Juglans ailantifolia Carrière is strongly associated with lower disease impact. Hybrid trees displayed an average of 2.4 cankers per tree compared with 4.5 cankers for nonhybrid butternut. Further niche and resistance studies are required to assess whether butternut hybrids can replace butternut in a natural setting. It still remains uncertain whether tree size or habitat affect disease impact; however, smaller trees, often residing in riparian habitats, were found to have a greater number of cankers. The data presented here, combined with past studies, provide critical information for use in butternut management strategy plans.

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McKenney, Daniel W., John H. Pedlar, Kevin Lawrence, Kathy Campbell, and Michael F. Hutchinson. "Potential Impacts of Climate Change on the Distribution of North American Trees." BioScience 57, no. 11 (2007): 939–48. http://dx.doi.org/10.1641/b571106.

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Greene, D. F., and E. A. Johnson. "Modelling the temporal variation in the seed production of North American trees." Canadian Journal of Forest Research 34, no. 1 (2004): 65–75. http://dx.doi.org/10.1139/x03-188.

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Many aspects of temporal variation in tree seed production (e.g., the proability distribution, periodicity, uni modality) are poorly understood. In this paper, we used 32 annual seed production records from 22 species to show that there are no discernible endogenous cycles, and there is a modest (but seldom significant) tendency for a high seed production year to be followed by an unusually low production year. Finally, we found that all of the records conformed to a single lognormal probability distribution, although our ability to discriminate among species, given short and extremely variable records, is admittedly very limited. We used the lognormal to develop the distribution of the sums of local seed production events (summed across 4 years) as an aid in predicting postharvest or postfire tree regeneration success. Our conclusion is that reliable (defined as 90% of the time) adequate stocking at the edge of an area source requires that the species of interest must comprise a very large fraction of the total basal area per area. Indeed, if the species constitutes less than about 50% of the source, neither burns nor even very narrow strip cuts will be reliably stocked.

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Strauss, Steven H., Allan H. Doerksen, and Joyce R. Byrne. "Evolutionary relationships of Douglas-fir and its relatives (genus Pseudotsuga) from DNA restriction fragment analysis." Canadian Journal of Botany 68, no. 7 (1990): 1502–10. http://dx.doi.org/10.1139/b90-191.

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We used restriction fragment analysis of chloroplast, nuclear, and mitochondrial DNA to study phylogeny in the genus Pseudotsuga. Total genomic DNA from one outgroup (Larix occidentalis Nutt.) and five Pseudotsuga species from Japan, mainland China, Taiwan, and North America were digested with 20 restriction enzymes, blotted, and probed up to 17 times with cloned DNA fragments. A total of 38 shared fragment characters were subjected to Wagner parsimony analysis coupled with bootstrapping to evaluate statistical significance of the phylogenetic trees. The complex patterns that we observed for actin gene fragments were evaluated via a Fitch–Margoliash distance-matrix analysis. Both parsimony and distance-matrix analyses indicated that relationships among species in the genus coincide with their current geographic distribution; genetic similarity declines with migration distance around the Pacific Rim. The Asian and North American species form well-differentiated and statistically significant monophyletic groups. Pseudotsuga japonica is the Asian species closest to the North American species. Affinities to the outgroup Larix occidentalis suggest that Pseudotsuga originated in North America and then migrated into Asia. Key words: parsimony, phylogeny, biogeography, conifer, Pinaceae.

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Newhouse, Andrew E., Jesse E. Spitzer, Charles A. Maynard, and William A. Powell. "Chestnut Leaf Inoculation Assay as a Rapid Predictor of Blight Susceptibility." Plant Disease 98, no. 1 (2014): 4–9. http://dx.doi.org/10.1094/pdis-01-13-0047-re.

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American chestnuts (Castanea dentata), effectively eliminated from eastern North America by chestnut blight in the twentieth century, are the subject of multiple restoration efforts. Screening individual trees (or tree types) for blight resistance is a critical step in all of these programs. Traditional screening involves inoculating stems of >3-year-old trees with the blight fungus (Cryphonectria parasitica), then measuring resulting cankers a few months later. A quicker, nondestructive, quantitative assay, usable on younger plants, would enhance restoration efforts by speeding the screening process. The assay presented here meets these requirements by inoculating excised leaves with the blight fungus and measuring resulting necrotic lesions. Leaves can be collected from few-month-old seedlings or fully mature trees, and results are measured after less than a week. Leaves from several lines of both American and Chinese chestnuts were inoculated, as well as the congener Allegheny chinquapin, and experimental leaf assay results correlate well with stem assay results from these species. Inoculations with virulent and hypovirulent blight fungi strains also showed relative patterns similar to traditional inoculations. Given the correlations to established stem assay results, this procedure could be a valuable tool to quickly evaluate blight resistance in American chestnut trees used for restoration.

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Holtz, C. T., A. R. Tull, and S. A. Merkle. "Influence of species and hybrid status on induction of somatic embryogenesis in Castanea." Canadian Journal of Forest Research 47, no. 3 (2017): 382–88. http://dx.doi.org/10.1139/cjfr-2016-0362.

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The American chestnut (AC; Castanea dentata (Marsh.) Borkh.) once dominated the forests of eastern North America prior to the introduction of chestnut blight in the late 19th century. A somatic embryogenesis (SE) system developed for American chestnut is potentially applicable for clonally propagating blight-resistant trees produced by The American Chestnut Foundation’s hybrid backcross breeding program. In this program, AC trees are hybridized with blight-resistant Chinese chestnut (CC; Castanea mollissima Blume) trees, followed by multiple generations of backcrossing to AC trees. It is possible, however, that the proportion of CC parental contribution in the hybrid backcross material could affect the success of SE using the AC protocol. Over three years of culture initiations, we tested the effects of the relative parental contributions of AC and CC on the success of SE induction using our standard AC culture initiation protocol and, subsequently, a published protocol for SE in European chestnut (Castanea sativa Mill.). With our standard AC protocol, open-pollinated AC and open- and control-pollinated hybrid backcross BC3F3 seed explants, as well as open-pollinated BC2 seed explants, successfully produced embryogenic tissue, while CC, F1, and BC1 explants did not. The European chestnut protocol produced Chinese chestnut embryogenic tissue and, subsequently, somatic embryos. The first BC3F3 somatic seedlings are currently growing in field tests.

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Morin, Patrick, Dominique Berteaux, and Ilya Klvana. "Hierarchical habitat selection by North American porcupines in southern boreal forest." Canadian Journal of Zoology 83, no. 10 (2005): 1333–42. http://dx.doi.org/10.1139/z05-129.

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In habitat-selection studies, a multi-scale approach is considered necessary to ensure that all elements of selection are depicted and that management decisions accurately reflect the needs of the species under study. We examined hierarchy in summer habitat selection in North American porcupines (Erethizon dorsatum (L., 1758)) in Eastern Canada at the scales of landscape, home range, and single tree. We used radiotelemetry to locate and observe animals visually to record their behaviour and exact location in the habitat. Den use in summer was unexpectedly high for some of our animals, which forced us to use a restricted number of locations per individual for comparison among scales. Although porcupines are generalists at the landscape level, selection patterns appear at the home-range and tree levels. Human-used land and conifer forests were least selected features of home ranges, while deciduous forests dominated by trembling aspen (Populus tremuloides Michx.) and mixed forests were most selected. At the tree scale, trembling aspen was found to be selected over other deciduous trees. However, fruit-producing trees were even more selected. This study shows the importance of a multi-scale approach that includes fine-scale selection.

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35

Brown et al. (iss. eds.), Kent. "Sixth NACW." Rangifer 16, no. 4 (1996): 7. http://dx.doi.org/10.7557/2.16.4.1213.

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The Sixth North American Caribou workshop was attended by over 200 people from across North America, as well as four special guests from Russia. Participants were very surprised to see and hear about caribou living in large cedar forests and on mountain-tops where snow depths exceeded several meters, and the only available forage was the lichens growing on trees. We believe that the workshop was a major success with many excellent presentations and posters, as well as opportunities for the participants to meet and discuss caribou research, ecology, and management with their counterparts from across North America. These proceedings include a wide range of excellent papers that provide a permanent record of the workshop. The editors thank the authors and reviewers for their efforts to produce and review these papers.

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Havill, Nathan P., Christopher S. Campbell, Thomas F. Vining, Ben LePage, Randall J. Bayer, and Michael J. Donoghue. "Phylogeny and Biogeography of Tsuga (Pinaceae) Inferred from Nuclear Ribosomal ITS and Chloroplast DNA Sequence Data." Systematic Botany 33, no. 3 (2008): 478–89. http://dx.doi.org/10.1600/036364408785679770.

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Hemlock, Tsuga (Pinaceae), has a disjunct distribution in North America and Asia. To examine the biogeographic history of Tsuga, phylogenetic relationships among multiple accessions of all nine species were inferred using chloroplast DNA sequences and multiple cloned sequences of the nuclear ribosomal ITS region. Analysis of chloroplast and ITS sequences resolve a clade that includes the two western North American species, T. heterophylla and T. mertensiana, and a clade of Asian species within which one of the eastern North American species, T. caroliniana, is nested. The other eastern North American species, T. canadensis, is sister to the Asian clade. Tsuga chinensis from Taiwan did not group with T. chinensis from mainland China, and T. sieboldii from Ullung Island did not group with T. sieboldii from Japan suggesting that the taxonomic status of these distinct populations should be reevaluated. The Himalayan species, T. dumosa, was in conflicting positions in the chloroplast and ITS trees, suggesting that it may be of hybrid origin. Likelihood-based biogeographic inference with divergence time estimates infers an Eocene basal crown group diversification and an initial widespread circumpolar distribution with subsequent vicariance and extinction events leading to the current disjunct distribution.

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Lee, Chang-Shook, and Stephen R. Downie. "Phylogenetic relationships within Cicuta (Apiaceae tribe Oenantheae) inferred from nuclear rDNA ITS and cpDNA sequence data." Canadian Journal of Botany 84, no. 3 (2006): 453–68. http://dx.doi.org/10.1139/b06-016.

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The genus Cicuta (Apiaceae tribe Oenantheae Dumort.) is the most virulently poisonous group of flowering plants native to the north temperate zone. A recent treatment recognized four species ( C. bulbifera L., C. douglasii (DC.) J.M. Coult. & Rose, C. maculata L., and C. virosa L.), with C. maculata divided into four varieties. We present results of phylogenetic analyses of the nuclear ribosomal DNA (rDNA) internal transcribed spacer (ITS) locus and the region bounded by the chloroplast genes psbI and trnK 5′ exon to determine taxonomic limits and relationships among these taxa, and to assess the taxonomic status of C. douglasii, a polyploid thought to be derived from C. maculata and C. virosa. Cicuta bulbifera and C. virosa are each resolved as monophyletic, the latter is a sister group to all other species. Discordance between the ITS- and plastid-derived phylogenies and lack of resolution in the ITS trees preclude unequivocal hypotheses of relationship; all trees do suggest, however, that the allotetraploid C. douglasii is polyphyletic and possibly polytopic, with all examined accessions but one nested within C. maculata. This single outstanding accession is from California and, pending further study, might warrant recognition as a distinct species. The diploid C. bulbifera may also be of hybrid origin, as revealed by significant discordance between data sets. Within C. maculata, only the western North American var. angustifolia Hook. is resolved in the ITS trees. In the cpDNA trees, C. maculata var. angustifolia comprises a strongly supported clade with C. maculata var. bolanderi (S. Watson) G.A. Mulligan and C. douglasii, both of primarily western North American distribution. The eastern North American taxa, C. maculata vars. maculata and victorinii (Fernald) B. Boivin, also comprise a clade, sister group to C. bulbifera.

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Kolyada, N. A. "THE ESTIMATE OF PERSPECTIVENESS OF INTRODUCTION OF SOME NORTH-AMERICAN SPECIES OF FAMILY ROSACEAE JUSS IN THE ARBORETUM OF MOUNTAIN-TAIGA STATION OF FAR-EASTERN BRANCH OF THE RUSSIAN ACADEMY OF SCIENCES." Vestnik of Samara University. Natural Science Series 17, no. 5 (2017): 153–60. http://dx.doi.org/10.18287/2541-7525-2011-17-5-153-160.

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The estimate of perspectiveness of 20 species of North-American trees andbushes of the family of Rosaceae which are cultivated in the arboretum ofMountain-Taiga station of FEB RAS. Higher indicators (96–97 points) haveAmelanchier spicata, A. alnifolia, Aronia melanocarpa, Physocarpus opulifolia,P. monogynus, P. capitatus, Prunus americana, Rubus odoratus, Rubus occidentalis. Quite perspective (82–90 points) are Cerasus besseyi, Crataegus flabellate,C. macracantha, C. rotundifolia, C. submollis, Padus pensylvanica, P. serotina,P virginiana, Rosa nutcana, Sorbus americana. Less perspective (67 points) anddemanding further study is Rosa Palnstris.

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39

Dusabenyagasani, M., G. Laflamme, and R. C. Hamelin. "Nucleotide polymorphisms in three genes support host and geographic speciation in tree pathogens belonging toGremmeniellaspp." Canadian Journal of Botany 80, no. 11 (2002): 1151–59. http://dx.doi.org/10.1139/b02-103.

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We detected nucleotide polymorphisms within the genus Gremmeniella in DNA sequences of β-tubulin, glyceraldehyde phosphate dehydrogenase, and mitochondrial small subunit rRNA (mtSSU rRNA) genes. A group-I intron was present in strains originating from fir (Abies spp.) in the mtSSU rRNA locus. This intron in the mtSSU rRNA locus of strains isolated from Abies sachalinensis (Fridr. Schmidt) M.T. Mast in Asia was also found in strains isolated from Abies balsamea (L.) Mill. in North America. Phylogenetic analyses yielded trees that grouped strains by host of origin with strong branch support. Asian strains of Gremmeniella abietina (Lagerberg) Morelet var. abietina isolated from fir (A. sachalinensis) were more closely related to G. abietina var. balsamea from North America, which is found on spruce (Picea spp.) and balsam fir, and European and North American races of G. abietina var. abietina from pines (Pinus spp.) were distantly related. Likewise, North American isolates of Gremmeniella laricina (Ettinger) O. Petrini, L.E. Petrini, G. Laflamme, & G.B. Ouellette, a pathogen of larch, was more closely related to G. laricina from Europe than to G. abietina var. abietina from North America. These data suggest that host specialization might have been the leading evolutionary force shaping Gremmeniella spp., with geographic separation acting as a secondary factor.Key words: Gremmeniella, geographic separation, host specialization, mitochondrial rRNA, nuclear genes.

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40

Fry, Joel T. "An international catalogue of North American trees and shrubs: the Bartram broadside, 1783." Journal of Garden History 16, no. 1 (1996): 3–66. http://dx.doi.org/10.1080/14601176.1996.10435636.

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41

Fell, Michael, and Kiona Ogle. "Refinement of a theoretical trait space for North American trees via environmental filtering." Ecological Monographs 88, no. 3 (2018): 372–84. http://dx.doi.org/10.1002/ecm.1294.

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42

Qian, Hong, John J. Wiens, Jian Zhang, and Yangjian Zhang. "Evolutionary and ecological causes of species richness patterns in North American angiosperm trees." Ecography 38, no. 3 (2014): 241–50. http://dx.doi.org/10.1111/ecog.00952.

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Peltier, Drew M. P., and Kiona Ogle. "Legacies of La Niña: North American monsoon can rescue trees from winter drought." Global Change Biology 25, no. 1 (2018): 121–33. http://dx.doi.org/10.1111/gcb.14487.

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Hewitt, Nina. "Seed size and shade-tolerance: a comparative analysis of North American temperate trees." Oecologia 114, no. 3 (1998): 432. http://dx.doi.org/10.1007/s004420050467.

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45

Giencke, Lisa M., Martin Dovčiak, Giorgos Mountrakis, Jonathan A. Cale, and Myron J. Mitchell. "Beech bark disease: spatial patterns of thicket formation and disease spread in an aftermath forest in the northeastern United States." Canadian Journal of Forest Research 44, no. 9 (2014): 1042–50. http://dx.doi.org/10.1139/cjfr-2014-0038.

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Beech bark disease (BBD) has affected the composition, structure, and function of forests containing a significant proportion of American beech (Fagus grandifolia Ehrh.) across North America. BBD spread has been investigated at landscape and regional scales, but few studies have examined spatial patterns of disease severity and spread within stands where forest management mitigation measures can be implemented. We analyzed changes in forest composition between 1985 and 2009 and fine-scale spatial patterns of BBD between 2000 and 2009 in a ∼2 ha northern hardwood stand in the Adirondack Mountains of New York using location and disease severity of beech trees. A bivariate point pattern analysis was implemented to examine spatial patterns of beech thicket formation and BBD spread to beech saplings. Abundance of beech saplings increased near highly diseased canopy beech trees and around dead beech and sugar maple (Acer saccharum Marsh.). Disease severity of beech saplings was highest in close proximity to highly cankered canopy beech trees. Thus, BBD leads to the formation of beech thickets, and thickets are often located where saplings are most likely to become infected, increasing the likelihood that secondary killing fronts will develop and lead to heavy BBD-induced mortality in aftermath northern hardwood forests of North America.

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Rahmani, Aviva. "The Music of the Trees: The Blued Trees Symphony and Opera as Environmental Research and Legal Activism." Leonardo Music Journal 29 (December 2019): 8–13. http://dx.doi.org/10.1162/lmj_a_01055.

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The Blued Trees project is a transdisciplinary thought experiment, physically manifested across miles of the North American continent. It melds ideas about music, acoustics, art and environmental policy. Hundreds of GPS-located individual trees in the path of proposed natural gas pipelines were painted with a sine wave sigil. Each “treenote” contributed to an aerially perceivable composition employing the local terrain. The score is the formal skeleton for systemic changes challenging several laws. A mock trial explored how this project might open new directions in legal activism for Earth rights and contribute to an operatic libretto.

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Martinson, S. J., A. A. Fernádez Ajó, A. S. Martínez, et al. "Attack rates ofSirex noctilioand patterns of pine tree defenses and mortality in northern Patagonia." Bulletin of Entomological Research 109, no. 2 (2018): 141–49. http://dx.doi.org/10.1017/s0007485318000184.

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AbstractAccidental and intentional global movement of species has increased the frequency of novel plant–insect interactions. In Patagonia, the European woodwasp,Sirex noctilio, has invaded commercial plantations of North American pines. We compared the patterns of resin defenses andS. noctilio-caused mortality at two mixed-species forests near San Carlos de Bariloche, Argentina. We observed lower levels of resin flow and higher levels of mortality inPinus contortacompared withPinus ponderosa. In general,S. noctilioattacked trees with lower resin compared with neighboring trees. Resin production inP. ponderosawas not related to growth rates, but forP. contorta, slower growing trees produced less resin than faster growing conspecifics. For all infested trees, attack density and number of drills (ovipositor probes) per attack did not vary with resin production. Most attacks resulted in one or two drills. Attack rates and drills/attack were basically uniform across the bole of the tree except for a decrease in both drills/attack and attack density in the upper portion of the crown, and an increase in the attack density for the bottom 10% of the tree. Planted pines in Patagonia grow faster than their counterparts in North America, and produce less resin, consistent with the growth-differentiation balance hypothesis. Limited resin defenses may help to explain the high susceptibility ofP. contortato woodwasps in Patagonia.

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Setliff, E. C. "The wound pathogen Chondrostereum purpureum, its history and incidence on trees in North America." Australian Journal of Botany 50, no. 5 (2002): 645. http://dx.doi.org/10.1071/bt01058.

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Since Percival's inoculation studies in 1902 with the wound pathogen Chondrostereum purpureum (Pers.�:�Fr.) Pouz. on plum trees in England, this fungus has become well known as the cause of silver-leaf disease of rosaceous fruit trees. However, its pathological impact on forest trees has been little studied and appreciated. Therefore, the question is raised about the pathogenic role and incidence of C. purpureum on other trees in damaged forests. A survey of 561 collections of this fungus in herbaria of Canada and the United States found that the highest incidence occurred in the Betulaceae (45%), especially Betula (27%) and Alnus (15%). The second-most favoured host family was the Salicaceae (20%) with a 15 and 5% occurrence on Populus and Salix, respectively. The third-most favoured substrate was apparently the Rosaceae at 11%, but this reflected a bias of agricultural research in orchards. A 6% incidence was found in the Fagaceae, 4% in the Aceraceae and 3% in the Ulmaceae. From 1 to 3% of the collections occurred for each of the Cornaceae, Juglandaceae, Magnoliaceae and Pinaceae. Incidences <1% were indicated for each of the Aquifoliaceae, Caprifoliaceae, Cupressaceae, Grossulariaceae, Hamamelidaceae, Hippocastanaceae, Myrtaceae, Oleaceae, Rhamnaceae and Tiliaceae. The host survey data indicate that C.�purpureum is an important pathogen with epidemic potential in forest trees, especially species in the Betulaceae and Salicaceae. The silvering symptom is inconspicuous in birch and other non-rosaceous trees. Forests with greatest vulnerability are those subjected (1) to physical forces that cause stem injuries to susceptible trees, (2) to environmental conditions conducive for infection and (3) to high levels of basidiospore inoculum from fruiting bodies on hardwood slash that result from timber harvesting and storm damage. Silver-leaf is an important fungal disease of many tree species in North America and is largely responsible for the birch dieback in North American forests. Control data from several mycoherbicide experiments support this conclusion.

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Dara, Surendra K., Cristian Montalva, and Marek Barta. "Microbial Control of Invasive Forest Pests with Entomopathogenic Fungi: A Review of the Current Situation." Insects 10, no. 10 (2019): 341. http://dx.doi.org/10.3390/insects10100341.

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The health of the forestlands of the world is impacted by a number of insect pests and some of them cause significant damage with serious economic and environmental implications. Whether it is damage of the North American cypress aphid in South America and Africa, or the destruction of maple trees in North America by the Asian long horned beetle, invasive forest pests are a major problem in many parts of the world. Several studies explored microbial control opportunities of invasive forest pests with entomopathogenic bacteria, fungi, and viruses, and some are successfully utilized as a part of integrated forest pest management programs around the world. This manuscript discusses some invasive pests and the status of their microbial control around the world with entomopathogenic fungi.

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McIlwrick, Ken, S. Wetzel, T. Beardmore, and K. Forbes. "Ex situ conservation of American chestnut (Castanea dentata (Marsh.) Borkh.) and butternut (Juglans cinerea L.), a review." Forestry Chronicle 76, no. 5 (2000): 765–74. http://dx.doi.org/10.5558/tfc76765-5.

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Two tree species native to North America, American chestnut (Castanea dentata (Marsh.) Borkh.) and butternut (Juglans cinerea L.), which have experienced rapid declines in their populations due to similar stressors (disease and changes in land use), are used as examples of how these species would benefit from ex situ conservation efforts. Current and past ex situ and in situ conservation efforts for these species are discussed and the focus of this review is on two key research areas: 1) what needs to be preserved (genetic information) and 2) how to preserve these trees or germplasm. Key words: butternut, American chestnut, Cryphonectria parasitica, Sirococcus clavigignenti-juglandacearum, ex situ conservation

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Journal articles on the topic 'North American trees'

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