| the use of ascorbic acid in the treatment of 2 cases of red maple (acer rubrum)-poisoned horses. | two horses with red maple (acer rubrum) toxicity responded to treatment with high doses of vitamin c (ascorbic acid), in addition to blood transfusions, and intravenous fluid therapy. the clinical course included heinz body anemia, marked methemoglobinemia, depression, and evidence of severe tissue anoxia. clinical recovery was dramatic with stabilization achieved 36 hours following the initiation of ascorbic acid therapy. | 1992 | 1643880 |
| hemolytic anemia in horses after the ingestion of red maple leaves. | signs of acute hemolytic anemia developed in 4 adult horses from 2 georgia farms 3 to 4 days after the ingestion of wilted leaves from cut red maple trees (acer rubrum). clinical findings included weakness, polypnea, tachycardia, depression, icterus, cyanosis, and brownish discoloration of the blood and urine. blood changes included methemoglobinemia, free plasma hemoglobin, decreased pcv, and heinz bodies in erythrocytes. these findings plus hemoglobinuria suggested intravascular hemolysis. thr ... | 1982 | 7056681 |
| heinz body anemia and methemoglobinemia in ponies given red maple (acer rubrum l.) leaves. | ponies given dried red maple (acer rubrum l.) leaves at a dose of 3.0 gm/kg body weight became ill and died one to five days after administration of the leaves. two clinical patterns of disease were seen. ponies given dried leaves collected after september 15 died by 18 hours, while ponies given dried leaves collected before september 15 became ill with a hemolytic syndrome and died by three to five days. freshly harvested leaves administered immediately after collection did not produce disease ... | 1982 | 7147611 |
| acute hemolytic anemia, methemoglobinemia, and heinz body formation associated with ingestion of red maple leaves by horses. | from june 1975 through june 1979, acute hemolytic anemia developed in 11 horses from 7 new york farms. of the 7 horses that died, 6 had methemoglobinemia. in the 4 horses that recovered, methemoglobinemia was not observed. but heinz body formation was seen in 3 of the 4. on 2 of the premises involved, frank methemoglobinemia was observed concurrently with heinz body formation, suggesting a relationship between the pathogenesis of methemoglobinemia and heinz body formation in the hemolytic proce ... | 1981 | 7263466 |
| suspected red maple (acer rubrum) toxicosis with abortion in two percheron mares. | horses develop severe and often fatal hemolytic anemia after ingesting dried leaves from red maple (acer rubrum) trees. toxicosis appears related to an unknown oxidant present in the dried or wilted leaves. this case report describes 2 horses that aborted and developed fatal hemolytic anemia after consuming wilted leaves from red maple (acer rubrum). while an absolute diagnosis was not confirmed due to lack of proper antemortem and postmortem examinations, red maple toxicosis appeared a reasonab ... | 1993 | 8351795 |
| hardwood seeding root and nutrient parameters for a model of nutrient uptake. | use of mechanistic models is an increasingly accepted way to evaluate complex processes. the barber-cushman model provides a means to simulate nutrient uptake once information on root system characteristics, nutrient uptake, and soil nutrient supply are developed. objectives of this study were to determine during a growing season: (i) root growth for 1-yr-old black cherry (prunus serotina ehrh.), northern red oak (quercus rubra l.), and red maple (acer rubrum l.) seedlings; (ii) net plant increa ... | 2001 | 11285903 |
| ice storm damage and early recovery in an old-growth forest. | we quantified the damage caused by a major ice storm to individual trees in two 1-ha permanent plots located at mont st. hilaire in southwestern québec, canada. the storm, which occurred in january 1998, is the worst on record in eastern north america; glaze ice on the order of 80-100 mm accumulated at our study site. all but 3% of the trees (dbh > or = 10 cm) lost at least some crown branches, and 35% lost more than half their crown. damage to trees increased in the order: tsuga canadensis, bet ... | 2001 | 11339708 |
| isolation, identification, and characterization of compounds from acer rubrum capable of oxidizing equine erythrocytes. | to identify compounds in acer rubrum that cause hemolysis or oxidation of equine erythrocytes and determine whether these toxins are found in other acer spp. | 2002 | 11939327 |
| energy investment in leaves of red maple and co-occurring oaks within a forested watershed. | despite its recent expansion in eastern us forests, red maple (acer rubrum l.) generally exhibits a low leaf photosynthetic rate, leaf mass per unit area (lma) and leaf nitrogen concentration ([n]) relative to co-occurring oaks (quercus spp.). to evaluate these differences from the perspective of leaf energy investment, we compared leaf construction cost (cc) and leaf maintenance cost (mc) with leaf photosynthetic rate at saturating photon flux density and ambient co2 partial pressure (amax) in ... | 2002 | 12184975 |
| optical properties of intact leaves for estimating chlorophyll concentration. | changes in leaf chlorophyll content can serve as relative indicators of plant vigor and environmental quality. this study identified reflectance, transmittance, and absorptance wavebands and band ratios within the 400- to 850-nm range for intact leaves that could be used to estimate extracted leaf chlorophyll per unit leaf area (areal concentration) with minimal error. leaf optical properties along with chlorophyll a, b, and a + b concentrations were measured for the planar-leaved sweetgum (liqu ... | 2002 | 12371158 |
| does canopy position affect wood specific gravity in temperate forest trees? | the radial increases in wood specific gravity known in many tree species have been interpreted as providing mechanical support in response to the stresses associated with wind loading. this interpretation leads to the hypothesis that individuals reaching the canopy should (1) be more likely to have radial increases in specific gravity and (2) exhibit greater increases than individuals in the subcanopy. wood specific gravity was determined for three species of forest trees (acer rubrum, fagus gra ... | 2003 | 12646497 |
| survival and development of lymantria monacha (lepidoptera: lymantriidae) on north american and introduced eurasian tree species. | lymantria monacha (l.) (lepidoptera: lymantriidae), the nun moth, is a eurasian pest of conifers that has potential for accidental introduction into north america. to project the potential host range of this insect if introduced into north america, survival and development of l. monacha on 26 north american and eight introduced eurasian tree species were examined. seven conifer species (abies concolor, picea abies, p. glauca, p. pungens, pinus sylvestris with male cones, p. menziesii variety gla ... | 2003 | 12650343 |
| growth and photosynthetic responses of four virginia piedmont tree species to shade. | to determine the effects of shade on biomass, carbon allocation patterns and photosynthetic response, seedlings of loblolly pine (pinus taeda l.), white pine (pinus strobus l.), red maple (acer rubrum l.), and yellow-poplar (liriodendron tulipifera l.) were grown without shade or in shade treatments providing a 79 or 89% reduction of full sunlight for two growing seasons. the shade treatments resulted in less total biomass for all species, with loblolly pine showing the greatest shade-induced gr ... | 1996 | 14871684 |
| estimates of net photosynthetic parameters for twelve tree species in mature forests of the southern appalachians. | leaf gas exchange, temperature, and incident radiation were measured in situ for 20 mature trees of 12 deciduous species spanning a range of heights from 7.9 to 30.1 m and growing in the southern appalachian mountains. air temperature, water vapor pressure, total radiation, photosynthetically active radiation, and carbon dioxide concentration were also measured. estimated mean, light-saturated net assimilation rates ( micro mol m(-2) s(-1)) were: quercus coccinea muenchh. (10.3), q. prinus l. (9 ... | 1996 | 14871725 |
| effects of elevated co(2) and light availability on the photosynthetic light response of trees of contrasting shade tolerance. | photosynthetic light response curves (a/ppfd), leaf n concentration and content, and relative leaf absorbance (alpha(r)) were measured in 1-year-old seedlings of shade-intolerant betula papyrifera marsh., moderately shade-tolerant quercus rubra l. and shade-tolerant acer rubrum l. seedlings were grown in full sun or 26% of full sun (shade) and in ambient (350 ppm) or elevated (714 ppm) co(2) for 80 days. in the shade treatments, 80% of the daily ppfd on cloud-free days was provided by two 30-min ... | 1996 | 14871736 |
| shade, leaf growth and crown development of quercus rubra, quercus velutina, prunus serotina and acer rubrum seedlings. | the study was conducted in an open field to determine the optimum irradiance for establishment and growth of two oak species and two major associated woody species. half-sib seedlings of black cherry (prunus serotina ehrh.), red maple (acer rubrum l.), northern red oak (quercus rubra l.) and black oak (q. velutina lam.) were grown for two years under shade-cloth tents. eight shade treatments (94, 70, 57, 45, 37, 27, 20 and 8% of full sunlight) with three replications each were used. measurements ... | 1994 | 14967644 |
| genotypic and phenotypic variation as stress adaptations in temperate tree species: a review of several case studies. | species that occupy large geographic ranges or a variety of habitats within a limited area deal with contrasting environmental conditions by genotypic and phenotypic variation. my students and i have studied these forms of ecophysiological variation in temperate tree species in eastern north america by means of a series of field and greenhouse experiments, including controlled studies with cercis canadensis l., fraxinus pennsylvanica marsh., acer rubrum l., prunus serotina ehrh. and quercus rubr ... | 1994 | 14967652 |
| comparative water relations of three successional hardwood species in central wisconsin. | water relations of co-occurring understory saplings of quercus ellipsoidalis e.j. hill, an early successional, xeric species, populus tremuloides michx., an early successional, mesic species, and acer rubrum l., a late successional species that occurs on both wet and dry sites, were evaluated on four dates during the 1986 growing season. the understory was characterized by high soil water content, low irradiance and low vapor pressure deficit throughout the growing season. stomatal conductance a ... | 1988 | 14972816 |
| environmental controls on sap flow in a northern hardwood forest. | our objective was to gain a detailed understanding of how photosynthetically active radiation (par), vapor pressure deficit (d) and soil water interact to control transpiration in the dominant canopy species of a mixed hardwood forest in northern lower michigan. an improved understanding of how these environmental factors affect whole-tree water use in unmanaged ecosystems is necessary in assessing the consequences of climate change on the terrestrial water cycle. we used continuously heated sap ... | 2005 | 15519983 |
| element accumulation patterns of deciduous and evergreen tree seedlings on acid soils: implications for sensitivity to manganese toxicity. | foliar nutrient imbalances, including the hyperaccumulation of manganese (mn), are correlated with symptoms of declining health in sensitive tree species growing on acidic forest soils. the objectives of this study were to: (1) compare foliar nutrient accumulation patterns of six deciduous (sugar maple (acer saccharum marsh.), red maple (acer rubrum l.), red oak (quercus rubra l.), white oak (quercus alba l.), black cherry (prunus serotina ehrh.) and white ash (fraxinus americana l.)) and three ... | 2005 | 15519989 |
| responses of floodplain forest species to spatially condensed gradients: a test of the flood-shade tolerance tradeoff hypothesis. | previous work in southeastern us floodplains led to the hypothesis that a tradeoff between flood and shade tolerance underlies species-specific responses to flooding and light, which drive forest regeneration. in systems where community turnover can occur with small-scale environmental changes, testing this hypothesis requires recognizing that turnover of species along the two gradients can be large relative to the spatial distances involved. we test the tradeoff hypothesis in an old-growth bott ... | 2006 | 16187107 |
| dark respiration rate increases with plant size in saplings of three temperate tree species despite decreasing tissue nitrogen and nonstructural carbohydrates. | in shaded environments, minimizing dark respiration during growth could be an important aspect of maintaining a positive whole-plant net carbon balance. changes with plant size in both biomass distribution to different tissue types and mass-specific respiration rates (r(d)) of those tissues would have an impact on whole-plant respiration. in this paper, we evaluated size-related variation in r(d), biomass distribution, and nitrogen (n) and total nonstructural carbohydrate (tnc) concentrations of ... | 2006 | 16585037 |
| red maple (acer rubrum) leaf toxicosis in horses: a retrospective study of 32 cases. | ingestion of wilted red maple leaves by horses can result in severe hemolytic anemia and methemoglobinemia. little is known about what factors influence the outcome of red maple leaf toxicosis in horses. | 2006 | 17063716 |
| agricultural legacies in forest environments: tree communities, soil properties, and light availability. | temperate deciduous forests across much of europe and eastern north america reflect legacies of past land use, particularly in the diversity and composition of plant communities. intense disturbances, such as clearing forests for agriculture, may cause persistent environmental changes that continue to shape vegetation patterns as landscapes recover. we assessed the long-term consequences of agriculture for environmental conditions in central new york forests, including tree community structure a ... | 2007 | 17489252 |
| impacts of an exotic disease and vegetation change on foliar calcium cycling in appalachian forests. | because of the high calcium content of its foliage, cornus florida (flowering dogwood) has been described as a calcium "pump" that draws calcium from deeper mineral soil and enriches surface soil horizons. however, over the last two decades an exotic fungal disease (dogwood anthracnose, discula destructiva) has decimated populations of this once-common understory species. its loss, combined with forest stand development, could alter intra-stand calcium cycling. we used data from long-term vegeta ... | 2007 | 17494403 |
| parenchyma cell respiration and survival in secondary xylem: does metabolic activity decline with cell age? | sapwood respiration often declines towards the sapwood/heartwood boundary, but it is not known if parenchyma metabolic activity declines with cell age. we measured sapwood respiration in five temperate species (sapwood age range of 5-64 years) and expressed respiration on a live cell basis by quantifying living parenchyma. we found no effect of parenchyma age on respiration in two conifers (pinus strobus, tsuga canadensis), both of which had significant amounts of dead parenchyma in the sapwood. ... | 2007 | 17617821 |
| relationships between advance oak regeneration and biotic and abiotic factors. | relationships between advance regeneration of four tree species (red maple (acer rubrum l.), white oak (quercus alba l.), chestnut oak (q. montana willd.) and northern red oak (q. rubra l.)) and biotic (non-tree vegetation and canopy composition) and abiotic (soil series and topographic variables) factors were investigated in 52, mature mixed-oak stands in the central appalachians. aggregate height was used as a composite measure of regeneration abundance. analyses were carried out separately fo ... | 2008 | 18450575 |
| senescence-related changes in nitrogen in fine roots: mass loss affects estimation. | the fate of nitrogen (n) in senescing fine roots has broad implications for whole-plant n economies and ecosystem n cycling. studies to date have generally shown negligible changes in fine root n per unit root mass during senescence. however, unmeasured loss of mobile non-n constituents during senescence could lead to underestimates of fine root n loss. for n fertilized and unfertilized potted seedlings of populus tremuloides michx., acer rubrum l., acer saccharum marsh. and betula alleghaniensi ... | 2009 | 19203982 |
| a modeling framework for inferring tree growth and allocation from physiological, morphological and allometric traits. | predictions of forest succession, diversity and function require an understanding of how species differ in their growth, allocation patterns and susceptibility to mortality. these processes in turn are affected by allometric constraints and the physiological state of the tree, both of which are coupled to the tree's labile carbon status. ultimately, insight into the hidden labile pools and the processes affecting the allocation of labile carbon to storage, maintenance and growth will improve our ... | 2009 | 19203984 |
| nematodes parasitic on forest trees: iii. reproduction on selected hardwoods. | the host-parasite relationships of 13 species of plant parasitic nematodes and five species of hardwoods native to the southeastern united states were tested on greenhouse-grown tree seedlings for 6-10 months. criteria for parasitism were completion o f life cycle and population increase of nematodes. belonolaimus longicaudatus, helicotylenchus dihystera, scutellonema brachyurum and tylenchorhynchus claytoni parasitized and reproduced on three or more of the species tested. hoplolaimus galeatus ... | 1971 | 19322363 |
| rapid decomposition of maize detritus in agricultural headwater streams. | headwater streams draining agricultural landscapes receive maize leaves (zea mays l.) via wind and surface runoff, yet the contribution of maize detritus to organic-matter processing in agricultural streams is largely unknown. we quantified decomposition and microbial respiration rates on conventional (non-bt) and genetically engineered (bt) maize in three low-order agricultural streams in northwestern indiana, usa. we also examined how substrate quality and in-stream nutrient concentrations inf ... | 2009 | 19323178 |
| simulating carbon dioxide exchange rates of deciduous tree species: evidence for a general pattern in biochemical changes and water stress response. | deciduous trees have a seasonal carbon dioxide exchange pattern that is attributed to changes in leaf biochemical properties. however, it is not known if the pattern in leaf biochemical properties - maximum rubisco carboxylation (v(cmax)) and electron transport (j(max)) - differ between species. this study explored whether a general pattern of changes in v(cmax), j(max), and a standardized soil moisture response accounted for carbon dioxide exchange of deciduous trees throughout the growing seas ... | 2009 | 19567419 |
| mapping urban forest tree species using ikonos imagery: preliminary results. | a stepwise masking system with high-resolution ikonos imagery was developed to identify and map urban forest tree species/groups in the city of tampa, florida, usa. the eight species/groups consist of sand live oak (quercus geminata), laurel oak (quercus laurifolia), live oak (quercus virginiana), magnolia (magnolia grandiflora), pine (species group), palm (species group), camphor (cinnamomum camphora), and red maple (acer rubrum). the system was implemented with soil-adjusted vegetation index ( ... | 2011 | 20140503 |
| northward migrating trees establish in treefall gaps at the northern limit of the temperate-boreal ecotone, ontario, canada. | climate change is expected to promote migration of species. in ecotones, areas of ecological tension, disturbances may provide opportunities for some migrating species to establish in otherwise competitive environments. the size of and time since disturbance may determine the establishment ability of these species. we investigated gap dynamics of an old-growth red pine (pinus resinosa sol. ex aiton) forest in the great lakes-st. lawrence forest in northern ontario, canada, a transition zone betw ... | 2010 | 20859751 |
| untangling positive and negative biotic interactions: views from above and below ground in a forest ecosystem. | in ecological communities, the outcome of plant-plant interactions represents the net effect of positive and negative interactions occurring above and below ground. untangling these complex relationships can provide a better understanding of mechanisms that underlie plant-plant interactions and enhance our ability to predict population, community, and ecosystem effects of biotic interactions. in forested ecosystems, tree seedlings interact with established vegetation, but the mechanisms and outc ... | 2010 | 21302835 |
| hydraulic patterns and safety margins, from stem to stomata, in three eastern u.s. tree species. | adequate water transport is necessary to prevent stomatal closure and allow for photosynthesis. dysfunction in the water transport pathway can result in stomatal closure, and can be deleterious to overall plant health and survival. although much is known about small branch hydraulics, little is known about the coordination of leaf and stem hydraulic function. additionally, the daily variations in leaf hydraulic conductance (k(leaf)), stomatal conductance and water potential (+¿(l)) have only bee ... | 2011 | 21724585 |
| the influence of land use and climate change on forest biomass and composition in massachusetts, usa. | land use and climate change have complex and interacting effects on naturally dynamic forest landscapes. to anticipate and adapt to these changes, it is necessary to understand their individual and aggregate impacts on forest growth and composition. we conducted a simulation experiment to evaluate regional forest change in massachusetts, usa over the next 50 years (2010-2060). our objective was to estimate, assuming a linear continuation of recent trends, the relative and interactive influence o ... | 2011 | 22073633 |
| the role of canopy structural complexity in wood net primary production of a maturing northern deciduous forest. | the even-aged northern hardwood forests of the upper great lakes region are undergoing an ecological transition during which structural and biotic complexity is increasing. early-successional aspen (populus spp.) and birch (betula papyrifera) are senescing at an accelerating rate and are being replaced by middle-successional species including northern red oak (quercus rubra), red maple (acer rubrum), and white pine (pinus strobus). canopy structural complexity may increase due to forest age, can ... | 2011 | 21939078 |
| identification of protoxins and a microbial basis for red maple (acer rubrum) toxicosis in equines. | the leaves of acer rubrum (red maple), especially when wilted in the fall, cause severe oxidative damage to equine erythrocytes, leading to potentially fatal methemoglobinemia and hemolytic anemia. gallic acid and tannins from a. rubrum leaves have been implicated as the toxic compounds responsible for red maple toxicosis, but the mechanism of action and toxic principle(s) have not been elucidated to date. in order to investigate further how red maple toxicosis occurs, aqueous solutions of galli ... | 2013 | 23242665 |
| insect herbivores increase mortality and reduce tree seedling growth of some species in temperate forest canopy gaps. | insect herbivores help maintain forest diversity through selective predation on seedlings of vulnerable tree species. although the role of natural enemies has been well-studied in tropical systems, relatively few studies have experimentally manipulated insect abundance in temperate forests and tracked impacts over multiple years. we conducted a three-year experiment (2012-2014) deterring insect herbivores from seedlings in new treefall gaps in deciduous hardwood forests in maryland. during this ... | 2017 | 28344904 |
| stomatal frequency responses in hardwood-swamp vegetation from florida during a 60-year continuous co2 increase. | in a stomatal frequency analysis of leaf remains of quercus nigra, acer rubrum, myrica cerifera, ilex cassine, and osmunda regalis that were preserved in precisely dated peat deposits of north-central florida, the stomatal index decreased as a response to an atmospheric co(2) increase from 310 ppmv to 370 ppmv over the past 60 years. the observations indicate that co(2) responsiveness may occur in different canopy levels of hardwood-swamp vegetation. apart from common woody plants, long-lived fe ... | 2005 | 21652447 |
| predicting and understanding forest dynamics using a simple tractable model. | the perfect-plasticity approximation (ppa) is an analytically tractable model of forest dynamics, defined in terms of parameters for individual trees, including allometry, growth, and mortality. we estimated these parameters for the eight most common species on each of four soil types in the us lake states (michigan, wisconsin, and minnesota) by using short-term (</=15-year) inventory data from individual trees. we implemented 100-year ppa simulations given these parameters and compared these pr ... | 2008 | 18971335 |
| biology and host associations of redbay ambrosia beetle (coleoptera: curculionidae: scolytinae), exotic vector of laurel wilt killing redbay trees in the southeastern united states. | the redbay ambrosia beetle, xyleborus glabratus eichhoff (coleoptera: curculionidae: scolytinae), and its fungal symbiont, raffaelea sp., are new introductions to the southeastern united states responsible for the wilt of mature redbay, persea borbonia (l.) spreng., trees. in 2006 and 2007, we investigated the seasonal flight activity of x. glabratus, its host associations, and population levels at eight locations in south carolina and georgia where infestations ranged from very recent to at lea ... | 2008 | 18767737 |
| deer herbivory alters forest response to canopy decline caused by an exotic insect pest. | hemlock woolly adelgid (hwa; adelges tsugae) infestations have resulted in the continuing decline of eastern hemlock (tsuga canadensis) throughout much of the eastern united states. while the initial impacts of hwa infestations have been documented, our understanding of forest response to this disturbance remains incomplete. hwa infestation is not occurring in isolation but within a complex ecological context. the role of potentially important interacting factors, such as elevated levels of whit ... | 2008 | 18488602 |
| oxidation of ingested phenolics in the tree-feeding caterpillar orgyia leucostigma depends on foliar chemical composition. | tannins are believed to function as antiherbivore defenses, in part, by acting as prooxidants. however, at the high ph found in the midguts of caterpillars, the oxidative activities of different types of tannins vary tremendously: ellagitannins >> galloyl glucoses > condensed tannins. ingested ascorbate is utilized by caterpillars to minimize phenolic oxidation in the midgut. thus, leaves that contain higher levels of reactive tannins and lower levels of ascorbate were hypothesized to produce hi ... | 2008 | 18473142 |
| contrasting below- and aboveground responses of two deciduous trees to patchy nitrate availability. | we investigated how patchy nitrate availability influences growth and functioning of plant roots and generates, through vascular constraints on long-distance transport, aboveground heterogeneity in plant growth and chemistry. we examined two broadleaf tree species, acer rubrum l. and betula papyrifera marsh. plants were grown either in a split-root setup where a single root received full nutrient supply and the rest of the root system received all nutrients except nitrogen (patchy treatment), or ... | 2008 | 17938112 |
| forest vegetation monitoring and foliar chemistry of red spruce and red maple at acadia national park in maine. | the usda forest service forest health monitoring (fhm) program indicators, including forest mensuration, crown condition classification, and damage and mortality indicators were used in the cadillac brook and hadlock brook watershed forests at acadia national park (anp) along coastal maine. cadillac brook watershed burned in a wildfire in 1947. hadlock brook watershed, undisturbed for several centuries, serves as the reference site. these two small watersheds have been gauged and monitored at an ... | 2007 | 17180435 |
| urbanization affects stream ecosystem function by altering hydrology, chemistry, and biotic richness. | catchment urbanization can alter physical, chemical, and biological attributes of stream ecosystems. in particular, changes in land use may affect the dynamics of organic matter decomposition, a measure of ecosystem function. we examined leaf-litter decomposition in 18 tributaries of the st. johns river, florida, usa. land use in all 18 catchments ranged from 0% to 93% urban which translated to 0% to 66% total impervious area (tia). using a litter-bag technique, we measured mass loss, fungal bio ... | 2006 | 17069372 |
| developing a media moisture threshold for nurseries to reduce tree stress and ambrosia beetle attacks. | exotic ambrosia beetles are among the most damaging pests of trees grown in nurseries. the primary pests xylosandrus crassiusculus motschulsky and xylosandrus germanus blandford use ethanol to locate vulnerable trees. research, primarily with x. germanus, has shown that flood-stressed trees emit ethanol and are preferentially attacked by ambrosia beetles. our goal was to develop a media (also called potting soil) moisture threshold as an integrated pest management (ipm) tactic and assess grower ... | 2016 | 27412195 |
| fast-growing acer rubrum differs from slow-growing quercus alba in leaf, xylem and hydraulic trait coordination responses to simulated acid rain. | we investigated the effects of historic soil chemistry changes associated with acid rain, i.e., reduced soil ph and a shift from nitrogen (n)- to phosphorus (p)-limitation, on the coordination of leaf water demand and xylem hydraulic supply traits in two co-occurring temperate tree species differing in growth rate. using a full-factorial design (n × p × ph), we measured leaf nutrient content, water relations, leaf-level and canopy-level gas exchange, total biomass and allocation, as well as stem ... | 2016 | 27231270 |
| interspecific variation in nighttime transpiration and stomatal conductance in a mixed new england deciduous forest. | transpiration is generally assumed to be insignificant at night when stomata close in response to the lack of photosynthetically active radiation. however, there is increasing evidence that the stomata of some species remain open at night, which would allow for nighttime transpiration if there were a sufficient environmental driving force. we examined nighttime water use in co-occurring species in a mixed deciduous stand at harvard forest, ma, using whole-tree and leaf-level measurements. diurna ... | 2006 | 16414920 |
| sapling growth as a function of light and landscape-level variation in soil water and foliar nitrogen in northern michigan. | interspecific differences in sapling growth responses to soil resources could influence species distributions across soil resource gradients. i calibrated models of radial growth as a function of light intensity and landscape-level variation in soil water and foliar n for saplings of four canopy tree species, which differ in adult distributions across soil resource gradients. model formulations, characterizing different resource effects and modes of influencing growth, were compared based on rel ... | 2006 | 16208492 |
| forest regeneration composition and development in upland, mixed-oak forests. | advance regeneration in 52 mature mixed-oak stands was analyzed and described. red maple (acer rubrum l.) was the most abundant species in the study area. among oak (quercus) species, northern red oak (q. rubra l.) was the most abundant within the allegheny plateau physiographic province, whereas chestnut oak (q. montana l.) was the most abundant within the ridge and valley physiographic province. sixteen stands, for which data are available through the fourth growing season following harvest, w ... | 2005 | 16137935 |
| does predation contribute to tree diversity? | seed and seedling predation may differentially affect competitively superior tree species to increase the relative recruitment success of poor competitors and contribute to the coexistence of tree species. we examined the effect of seed and seedling predation on the seedling recruitment of three tree species, acer rubrum (red maple), liriodendron tulipifera (yellow poplar), and quercus rubra (northern red oak), over three years by manipulating seed and seedling exposure to predators under contra ... | 2005 | 15719246 |
| responses of hybrid poplar clones and red maple seedlings to ambient o(3) under differing light within a mixed hardwood forest. | the responses of ramets of hybrid poplar (populus spp.) (hp) clones ne388 and ne359, and seedlings of red maple (acer rubrum, l.) to ambient ozone (o(3)) were studied during may-september of 2000 and 2001 under natural forest conditions and differing natural sunlight exposures (sun, partial shade and full shade). ambient o(3) concentrations at the study site reached hourly peaks of 109 and 98 ppb in 2000 and 2001, respectively. monthly 12-h average o(3) concentrations ranged from 32.3 to 52.9 pp ... | 2004 | 15158034 |
| environmental control of stomatal conductance in forest trees of the great smoky mountains national park. | to determine if stomatal conductance (g(s)) of forest trees could be predicted from measures of leaf microclimate, diurnal variability in in situ g(s) was measured in black cherry (prunus serotina), red maple (acer rubrum), and northern red oak (quercus rubra). relative to overstory trees, understory saplings exhibited little diurnal variability in g(s) and ozone uptake. depending on species and site, up to 30% of diurnal and seasonal variation in g(s )of overstory trees was explained by photosy ... | 2000 | 15092837 |
| effect of landfill leachate irrigation on red maple (acer rubrum l.) and sugar maple (acer saccharum marsh.) seedling growth and on foliar nutrient concentrations. | greenhouse experiments were conducted to investigate the nature and severity of stresses imposed on northern hardwood tree species (red maple (acer rubrum l.) and sugar maple (acer saccharum marsh.)) by the application of municipal landfill leachate. red maple seedlings received applications of untreated and pretreated (lime, activated carbon) leachate, to both leaves and soil, at irrigation rates consistent with evapotranspirational demands. plant height measurements indicated no significant gr ... | 1989 | 15092473 |
| ethyl m-digallate from red maple, acer rubrum l., as the major resistance factor to forest tent caterpillar, malacosoma disstria hbn. | an ethanolic extract of red maple (acer rubrum l.) leaves (rme) applied to trembling aspen (populus tremuloides michx.) leaves reduced feeding in choice test assays with forest tent caterpillar larvae (malacosoma disstria hbn.) (ftc), whereas a trembling aspen foliage extract, similarly applied, stimulated feeding. compounds isolated from the rme were gallic acid, methyl gallate, ethyl gallate, m-digallate, ethyl m-digallate, 1-o-galloyl-beta-d-glucose, 1-o-galloyl-alpha-l-rhamnose, kaempferol 3 ... | 2001 | 11789956 |
| food processing by animals: do beavers leach tree bark to improve palatability? | beavers store and consume tree parts in the bodies of water where they live. we examined whether such soaking renders food more palatable by leaching out undesirable compounds. in experiment 1, saplings of red maple, acer rubrum (rm), were first soaked in a pond for periods of 2, 18, and 36 days, then offered to free-ranging beavers. soaking for two days rendered rm slightly more acceptable to beavers. to further examine the time window around two days, rm sticks were soaked in distilled water i ... | 2001 | 11471937 |
| responses of leaf respiration to temperature and leaf characteristics in three deciduous tree species vary with site water availability. | we measured responses of leaf respiration to temperature and leaf characteristics in three deciduous tree species (quercus rubra l., quercus prinus l. and acer rubrum l.) at two sites differing in water availability within a single catchment in the black rock forest, new york. the response of respiration to temperature differed significantly among the species. acer rubrum displayed the smallest increase in respiration with increasing temperature. corresponding q(10) values ranged from 1.5 in a. ... | 2001 | 11390301 |
| cosmetic applications of glucitol-core containing gallotannins from a proprietary phenolic-enriched red maple (acer rubrum) leaves extract: inhibition of melanogenesis via down-regulation of tyrosinase and melanogenic gene expression in b16f10 melanoma cells. | the red maple (acer rubrum) is a rich source of phenolic compounds which possess galloyl groups attached to different positions of a 1,5-anhydro-d-glucitol core. while these glucitol-core containing gallotannins (gcgs) have reported anti-oxidant and anti-glycative effects, they have not yet been evaluated for their cosmetic applications. herein, the anti-tyrosinase and anti-melanogenic effects of a proprietary phenolic-enriched red maple leaves extract [maplifa(™); contains ca. 45% ginnalin a (g ... | 2017 | 28283753 |
| colonization of three maple species by asian longhorned beetle, anoplophora glabripennis, in two mixed-hardwood forest stands. | asian longhorned beetle (alb), anoplophora glabripennis (motschulsky), is an invasive insect that has successfully established multiple times in north america. to investigate host colonization and reproductive success (exit holes/eggs), two alb infested forest stands were sampled in central massachusetts, usa. infested acer platanoides l., acer rubrum l., and acer saccharum marsh. were felled, bucked into 1 m sections and dissected to determine indications of alb infestations, such as presence o ... | 2013 | 26462582 |
| inhibitory effects on bacterial growth and beta-ketoacyl-acp reductase by different species of maple leaf extracts and tannic acid. | it is important to develop new antibiotics aimed at novel targets. the investigation found that the leaf extracts from five maples (acer platanoides, acer campestre, acer rubrum, acer saccharum and acer truncatum bunge collected in denmark, canada and china) and their component tannic acid displayed antibacterial ability against 24 standard bacteria strains with the minimum inhibitory concentration of 0.3-8.0 mg/ml. unlike the standard antibiotic levofloxacin (lfx), these samples inhibited gram- ... | 2010 | 19444866 |
| interspecific coordination and intraspecific plasticity of fine root traits in north american temperate tree species. | fine roots play an important role in nutrient and water absorption and hence overall tree performance. however, current understanding of the ecological role of belowground traits lags considerably behind those of aboveground traits. in this study, we used data on specific root length (srl), fine root diameter (d) and branching intensity (bi) of two datasets to examine interspecific trait coordination as well as intraspecific trait variation across ontogenetic stage and soil conditions (i.e., pla ... | 2013 | 23874347 |
| host species identity, site and time drive temperate tree phyllosphere bacterial community structure. | the increasing awareness of the role of phyllosphere microbial communities in plant health calls for a greater understanding of their structure and dynamics in natural ecosystems. since most knowledge of tree phyllosphere bacterial communities has been gathered in tropical forests, our goal was to characterize the community structure and assembly dynamics of phyllosphere epiphytic bacterial communities in temperate forests in quebec, canada. we targeted five dominant tree species: acer saccharum ... | 2016 | 27316353 |
| native leaf-tying caterpillars influence host plant use by the invasive asiatic oak weevil through ecosystem engineering. | we tested the effect of leaf-tying caterpillars, native ecosystem engineers, on the abundance and host feeding of an invasive insect, the asiatic oak weevil, cyrtepistomus castaneus (roelofs). leaf quality was previously thought to be the sole factor determining host use by c. castaneus, but adult weevils congregate in leaf ties made by lepidopteran larvae (caterpillars). adult weevil abundance was naturally higher on quercus alba and q. velutina compared to four other tree species tested (acer ... | 2014 | 25039212 |
| is climate an important driver of post-european vegetation change in the eastern united states? | many ecological phenomena combine to direct vegetation trends over time, with climate and disturbance playing prominent roles. to help decipher their relative importance during euro-american times, we employed a unique approach whereby tree species/genera were partitioned into temperature, shade tolerance, and pyrogenicity classes and applied to comparative tree-census data. our megadata analysis of 190 datasets determined the relative impacts of climate vs. altered disturbance regimes for vario ... | 2015 | 24953341 |
| tree phyllosphere bacterial communities: exploring the magnitude of intra- and inter-individual variation among host species. | the diversity and composition of the microbial community of tree leaves (the phyllosphere) varies among trees and host species and along spatial, temporal, and environmental gradients. phyllosphere community variation within the canopy of an individual tree exists but the importance of this variation relative to among-tree and among-species variation is poorly understood. sampling techniques employed for phyllosphere studies include picking leaves from one canopy location to mixing randomly sele ... | 2016 | 27635335 |
| incorporating interspecific competition into species-distribution mapping by upward scaling of small-scale model projections to the landscape. | there are a number of overarching questions and debate in the scientific community concerning the importance of biotic interactions in species distribution models at large spatial scales. in this paper, we present a framework for revising the potential distribution of tree species native to the western ecoregion of nova scotia, canada, by integrating the long-term effects of interspecific competition into an existing abiotic-factor-based definition of potential species distribution (psd). the ps ... | 2017 | 28207782 |
| variation in whole dna methylation in red maple (acer rubrum) populations from a mining region: association with metal contamination and cation exchange capacity (cec) in podzolic soils. | although a number of publications have provided convincing evidence that abiotic stresses such as drought and high salinity are involved in dna methylation reports on the effects of metal contamination, ph, and cation exchange on dna modifications are limited. the main objective of the present study is to determine the relationship between metal contamination and cation exchange capacity (cec) on whole dna modifications. metal analysis confirms that nickel and copper are the main contaminants in ... | 2017 | 28204976 |
| effects of structural complexity on within-canopy light environments and leaf traits in a northern mixed deciduous forest. | canopy structure influences forest productivity through its effects on the distribution of radiation and the light-induced changes in leaf physiological traits. due to the difficulty of accessing and measuring forest canopies, few field-based studies have quantitatively linked these divergent scales of canopy functioning. the objective of our study was to investigate how canopy structure affects light profiles within a forest canopy and whether leaves of mature trees adjust morphologically and b ... | 2017 | 28100711 |
| foliar damage beyond species distributions is partly explained by distance dependent interactions with natural enemies. | plant distributions are expected to shift in response to climate change, and range expansion dynamics will be shaped by the performance of individuals at the colonizing front. these plants will encounter new biotic communities beyond their range edges, and the net outcome of these encounters could profoundly affect colonization success. however, little is known about how biotic interactions vary across range edges and this has hindered efforts to predict changes in species distributions in respo ... | 2016 | 27859086 |
| effects of two fungicide formulations on microbial and macroinvertebrate leaf decomposition under laboratory conditions. | aquatic fungi contribute significantly to the decomposition of leaves in streams, a key ecosystem service. little is known, however, about the effects of fungicides on aquatic fungi and macroinvertebrates involved with leaf decomposition. red maple (acer rubrum) leaves were conditioned in a stream to acquire microbes (bacteria and fungi) or leached in tap water (unconditioned) to simulate potential reduction of microbial biomass by fungicides. conditioned leaves were exposed to fungicide formula ... | 2016 | 27110671 |
| determination of dna methylation associated with acer rubrum (red maple) adaptation to metals: analysis of global dna modifications and methylation-sensitive amplified polymorphism. | red maple (acer rubum), a common deciduous tree species in northern ontario, has shown resistance to soil metal contamination. previous reports have indicated that this plant does not accumulate metals in its tissue. however, low level of nickel and copper corresponding to the bioavailable levels in contaminated soils in northern ontario causes severe physiological damages. no differentiation between metal-contaminated and uncontaminated populations has been reported based on genetic analyses. t ... | 2016 | 27547351 |
| litter species composition and topographic effects on fuels and modeled fire behavior in an oak-hickory forest in the eastern usa. | mesophytic species (esp. acer rubrum) are increasingly replacing oaks (quercus spp.) in fire-suppressed, deciduous oak-hickory forests of the eastern us. a pivotal hypothesis is that fuel beds derived from mesophytic litter are less likely than beds derived from oak litter to carry a fire and, if they do, are more likely to burn at lower intensities. species effects, however, are confounded by topographic gradients that affect overstory composition and fuel bed decomposition. to examine the sepa ... | 2016 | 27536964 |
| evaluating the ecological impacts of salvage logging: can natural and anthropogenic disturbances promote coexistence? | salvage logging following windthrow is common throughout forests worldwide even though the practice is often considered inimical to forest recovery. because salvaging removes trees, crushes seedlings, and compacts soils, many warn this practice may delay succession, suppress diversity, and alter composition. here, over 8 yr following windthrow, we experimentally evaluate how salvaging affects tree succession across 11 gaps in eastern deciduous forests of pennsylvania, wherein each gap was divide ... | 2016 | 27459786 |
| modeled effects of soil acidification on long-term ecological and economic outcomes for managed forests in the adirondack region (usa). | sugar maple (acer saccharum) is among the most ecologically and economically important tree species in north america, and its growth and regeneration is often the focus of silvicultural practices in northern hardwood forests. a key stressor for sugar maple (sm) is acid rain, which depletes base cations from poorly-buffered forest soils and has been associated with much lower sm vigor, growth, and recruitment. however, the potential interactions between forest management and soil acidification - ... | 2016 | 27179322 |
| glucitol-core containing gallotannins inhibit the formation of advanced glycation end-products mediated by their antioxidant potential. | glucitol-core containing gallotannins (gcgs) are polyphenols containing galloyl groups attached to a 1,5-anhydro-d-glucitol core, which is uncommon among naturally occurring plant gallotannins. gcgs have only been isolated from maple (acer) species, including the red maple (acer rubrum), a medicinal plant which along with the sugar maple (acer saccharum), are the major sources of the natural sweetener, maple syrup. gcgs are reported to show antioxidant, α-glucosidase inhibitory, and antidiabetic ... | 2016 | 27101975 |
| drought and shade deplete nonstructural carbohydrate reserves in seedlings of five temperate tree species. | plants that store nonstructural carbohydrates (nsc) may rely on carbon reserves to survive carbon-limiting stress, assuming that reserves can be mobilized. we asked whether carbon reserves decrease in resource stressed seedlings, and if nsc allocation is related to species' relative stress tolerances. we tested the effects of stress (shade, drought, and defoliation) on nsc in seedlings of five temperate tree species (acer rubrum marsh., betula papyrifera marsh., fraxinus americana l ., quercus r ... | 2015 | 27069619 |
| aboveground net primary productivity in a riparian wetland following restoration of hydrology. | this research presents the initial results of the effects of hydrological restoration on forested wetlands in the mississippi alluvial plain near memphis, tennessee. measurements were carried out in a secondary channel, the loosahatchie chute, in which rock dikes were constructed in the 1960s to keep most flow in the main navigation channel. in 2008-2009, the dikes were notched to allow more flow into the secondary channel. study sites were established based on relative distance downstream of th ... | 2016 | 26861409 |
| potential new associations of north american parasitoids with the invasive asian longhorned beetle (coleoptera: cerambycidae) for biological control. | the asian longhorned beetle, anoplophora glabripennis (motschulsky), is a polyphagous wood-boring insect native to asia. since it invaded north america in the 1990s, the beetle has been continuously targeted by quarantines and eradication programs in the united states and canada. we examined the potential for development of new species-associations between a. glabripennis and hymenopteran parasitoids collected from cerambycids and other wood-boring insects infesting red maple (acer rubrum l.) tr ... | 2016 | 26602779 |
| effects of nitrogen fertilization on potato leafhopper (hemiptera: cicadellidae) and maple spider mite (acari: tetranychidae) on nursery-grown maples. | although leaf nitrogen (n) has been shown to increase the suitability of hosts to herbivorous arthropods, the responses of these pests to n fertilization on susceptible and resistant host plants are not well characterized. this study determined how different rates of n fertilization affected injury caused by the potato leafhopper (empoasca fabae harris) and the abundance of maple spider mite (oligonychus aceris (shimer)) on 'red sunset' red maple (acer rubrum) and 'autumn blaze' freeman maple (a ... | 2015 | 26470249 |
| red maple (acer rubrum) aerial parts as a source of bioactive phenolics. | the bark and stems of red maple (acer rubrum) are reported to contain bioactive phenolics but its aerial parts, namely, flowers and leaves, remain largely unexplored. this is unfortunate considering that various parts of the red maple were used for traditional medicinal purposes by the indigenous peoples of eastern north america, where this species is found. herein, we report the identification of twenty-five (1-25) phenolics, including two new galloyl derivatives (1 and 2), from red maple flowe ... | 2015 | 26434129 |
| detrital stoichiometry as a critical nexus for the effects of streamwater nutrients on leaf litter breakdown rates. | nitrogen (n) and phosphorus (p) concentrations are elevated in many freshwater systems, stimulating breakdown rates of terrestrially derived plant litter; however, the relative importance of n and p in driving litter breakdown via microbial and detritivore processing are not fully understood. here, we determined breakdown rates of two litter species, acer rubrum (maple) and rhododendron maximum (rhododendron), before (pre) and during two years (yr1, yr2) of experimental n and p additions to five ... | 2015 | 26405746 |
| anthelmintic effect of plant extracts containing condensed and hydrolyzable tannins on caenorhabditis elegans, and their antioxidant capacity. | although tannin-rich forages are known to increase protein uptake and to reduce gastrointestinal nematode infections in grazing ruminants, most published research involves forages with condensed tannins (ct), while published literature lacks information on the anthelmintic capacity, nutritional benefits, and antioxidant capacity of alternative forages containing hydrolyzable tannins (ht). we evaluated the anthelmintic activity and the antioxidant capacity of plant extracts containing either most ... | 2013 | 23102761 |
| pharmacy research at uri: mining red maple (acer rubrum) trees for novel therapeutics to manage diabetes. | | 2012 | 23094425 |
| molecular analysis of red maple (acer rubrum) populations from a reclaimed mining region in northern ontario (canada): soil metal accumulation and translocation in plants. | red maple (acer rubrum) species is one of the most widespread deciduous (hardwood) trees of eastern north america. it is among the dominant tree species in the northern ontario after land reclamation. to date, the effects of heavy metal contamination from the mining activities on terrestrial ecosystems are not well understood. the main objectives of the present study are (1) to determine the level of phytoavailable metal in soil and accumulation in a. rubrum, and (2) to compare the levels of gen ... | 2015 | 25560741 |
| early autumn senescence in red maple (acer rubrum l.) is associated with high leaf anthocyanin content. | several theories exist about the role of anthocyanins in senescing leaves. to elucidate factors contributing to variation in autumn leaf anthocyanin contents among individual trees, we analysed anthocyanins and other leaf traits in 27 individuals of red maple (acer rubrum l.) over two growing seasons in the context of timing of leaf senescence. red maple usually turns bright red in the autumn, but there is considerable variation among the trees. leaf autumn anthocyanin contents were consistent b ... | 2015 | 27135339 |
| oxidant-induced damage to equine erythrocytes from exposure to pistacia atlantica, pistacia terebinthus, and pistacia chinensis. | two horses were referred for methemoglobinemia and hemolytic anemia following 5 acute deaths in their herd from an unidentified toxin source. horses have a greater risk than other mammalian species of developing methemoglobinemia and hemolytic anemia following ingestion of oxidizing toxins, due to deficiencies in the mechanisms that protect against oxidative damage in erythrocytes. their susceptibility to oxidative erythrocyte damage is evident in the numerous cases of red maple (acer rubrum) to ... | 2014 | 25227420 |
| do cities simulate climate change? a comparison of herbivore response to urban and global warming. | cities experience elevated temperature, co2 , and nitrogen deposition decades ahead of the global average, such that biological response to urbanization may predict response to future climate change. this hypothesis remains untested due to a lack of complementary urban and long-term observations. here, we examine the response of an herbivore, the scale insect melanaspis tenebricosa, to temperature in the context of an urban heat island, a series of historical temperature fluctuations, and recent ... | 2015 | 25163424 |
| community-specific impacts of exotic earthworm invasions on soil carbon dynamics in a sandy temperate forest. | exotic earthworm introductions can alter above- and belowground properties of temperate forests, but the net impacts on forest soil carbon (c) dynamics are poorly understood. we used a mesocosm experiment to examine the impacts of earthworm species belonging to three different ecological groups (lumbricus terrestris [anecic], aporrectodea trapezoides [endogeic], and eisenia fetida [epigeic]) on c distributions and storage in reconstructed soil profiles from a sandy temperate forest soil by measu ... | 2013 | 24597228 |
| experimentally reduced root-microbe interactions reveal limited plasticity in functional root traits in acer and quercus. | interactions between roots and soil microbes are critical components of below-ground ecology. it is essential to quantify the magnitude of root trait variation both among and within species, including variation due to plasticity. in addition to contextualizing the magnitude of plasticity relative to differences between species, studies of plasticity can ascertain if plasticity is predictable and whether an environmental factor elicits changes in traits that are functionally advantageous. | 2014 | 24363335 |
| drought enhances symbiotic dinitrogen fixation and competitive ability of a temperate forest tree. | general circulation models project more intense and frequent droughts over the next century, but many questions remain about how terrestrial ecosystems will respond. of particular importance, is to understand how drought will alter the species composition of regenerating temperate forests wherein symbiotic dinitrogen (n2)-fixing plants play a critical role. in experimental mesocosms we manipulated soil moisture to study the effect of drought on the physiology, growth and competitive interactions ... | 2014 | 24337710 |
| functional analysis of embolism induced by air injection in acer rubrum and salix nigra. | the goal of this study was to assess the effect of induced embolism with air injection treatments on the function of xylem in acer rubrum l. and salix nigra marsh. measurements made on mature trees of a. rubrum showed that pneumatic pressurization treatments that created a pressure gradient of 5.5 mpa across pit membranes (δp pit) had no effect on stomatal conductance or on branch-level sap flow. the same air injection treatments made on 3-year-old potted a. rubrum plants also had no effect on w ... | 2013 | 24069025 |
| age, allocation and availability of nonstructural carbon in mature red maple trees. | the allocation of nonstructural carbon (nsc) to growth, metabolism and storage remains poorly understood, but is critical for the prediction of stress tolerance and mortality. we used the radiocarbon ((14) c) 'bomb spike' as a tracer of substrate and age of carbon in stemwood nsc, co2 emitted by stems, tree ring cellulose and stump sprouts regenerated following harvesting in mature red maple trees. we addressed the following questions: which factors influence the age of stemwood nsc?; to what ex ... | 2013 | 24032647 |
| analysis of spatial and temporal dynamics of xylem refilling in acer rubrum l. using magnetic resonance imaging. | we report results of an analysis of embolism formation and subsequent refilling observed in stems of acer rubrum l. using magnetic resonance imaging (mri). mri is one of the very few techniques that can provide direct non-destructive observations of the water content within opaque biological materials at a micrometer resolution. thus, it has been used to determine temporal dynamics and water distributions within xylem tissue. in this study, we found good agreement between mri measures of pixel b ... | 2013 | 23885258 |
| variation in leaf and twig co2 flux as a function of plant size: a comparison of seedlings, saplings and trees. | rates of tissue-level function have been hypothesized to decline as trees grow older and larger, but relevant evidence to assess such changes remains limited, especially across a wide range of sizes from saplings to large trees. we measured functional traits of leaves and twigs of three cold-temperate deciduous tree species in minnesota, usa, to assess how these vary with tree height. individuals ranging from 0.13 to 20 m in height were sampled in both relatively open and closed canopy environme ... | 2013 | 23872734 |
| future species composition will affect forest water use after loss of eastern hemlock from southern appalachian forests. | infestation of eastern hemlock (tsuga canadensis (l.) carr.) with hemlock woolly adelgid (hwa, adelges tsugae) has caused widespread mortality of this key canopy species throughout much of the southern appalachian mountains in the past decade. because eastern hemlock is heavily concentrated in riparian habitats, maintains a dense canopy, and has an evergreen leaf habit, its loss is expected to have a major impact on forest processes, including transpiration (e(t)). our goal was to estimate chang ... | 2013 | 23865229 |
| simulated herbivory advances autumn phenology in acer rubrum. | to determine the degree to which herbivory contributes to phenotypic variation in autumn phenology for deciduous trees, red maple (acer rubrum) branches were subjected to low and high levels of simulated herbivory and surveyed at the end of the season to assess abscission and degree of autumn coloration. overall, branches with simulated herbivory abscised ∼7 % more leaves at each autumn survey date than did control branches within trees. while branches subjected to high levels of damage showed a ... | 2014 | 23832182 |
| testing a growth efficiency hypothesis with continental-scale phenological variations of common and cloned plants. | variation in the timing of plant phenology caused by phenotypic plasticity is a sensitive measure of how organisms respond to weather and climate variability. although continental-scale gradients in climate and consequential patterns in plant phenology are well recognized, the contribution of underlying genotypic difference to the geography of phenology is less well understood. we hypothesize that different temperate plant genotypes require varying amount of heat energy for resuming annual growt ... | 2014 | 23775129 |