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Showing 1 to 20 of 23 for “"tsuga canadensis"”.
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Development and properties of tracheids and their cell wall layers in eastern hemlock (Tsuga canadensis L.)
Changes in anatomical, physical and chemical properties within developing and one-year-old increments were investigated in a 52-year old eastern hemlock tree, felled in the latter part of July, 1968. Based on available previous knowledge, the zones of xylem maturation stages were determined by the …
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Fitness and Physiology of the Hemlock Woolly Adelgid, Adelges tsugae, in Relation to the Health of the Eastern Hemlock, Tsuga canadensis
The hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Sternorrhyncha: Adelgidae) is a small invasive insect that frequently causes hemlock (Tsugae spp.) mortality in the eastern United States. Studies have shown that once healthy hemlocks become infested by the adelgid, nutrients are …
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Impact of predation by Laricobius nigrinus (Coleoptera: Derodontidae) and Leucotaraxis spp. (Diptera: Chamaemyiidae) on Adelges tsugae (Hemiptera: Adelgidae) and Tsuga canadensis (Pinales: Pinaceae) tree health
The hemlock woolly adelgid (HWA), Adelges tsugae Annand, (Hemiptera: Adelgidae) is an invasive species in the eastern United States and Canada. This scale-like insect feeds on the xylem ray parenchyma cells of eastern hemlock, Tsuga canadensis (L.) Carrière, (Pinales: Pinaceae) and Carolina …
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In-Stream Hemlock Twig Breakdown and Effects of Reach-Scale Twig Additions on Appalachian Headwater Streams
Eastern hemlock (Tsuga canadensis) is a prominent tree in the forests of eastern North America, where it commonly grows along headwater streams. It is experiencing widespread mortality due to infestations of an introduced insect, the hemlock woolly adelgid (Adelges tsugae). Eliminations of tree …
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The Inhibitory Effect of Rhododendron maximum L. (Ericaceae) Thickets on Mycorrhizal Colonization of Canopy Tree Seedlings
… of red oak (Quercus rubra) and hemlock (Tsuga canadensis) were harvested at the end of the first and second growing seasons. Litter manipulation had no effect on total mycorrhizal colonization. Mycorrhizal colonization and ramification index (# mycorrhizae cm-1) were depressed and …
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Eastern Hemlock Needle Physiology as Impacted by Hemlock Wooly Adelgid and Treatment with Imidacloprid
Eastern hemlock (Tsuga canadensis [L.] Carr.) is a foundation species that occupies a unique niche in forest ecosystems and which often forms pure stands throughout the eastern United States. Throughout the last half of a century, widespread mortality of T. canadensis had been occurring with the …
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Radial growth response of eastern hemlock to infestation of hemlock woolly adelgid
Hemlock woolly adelgid (Adelges tsugae Annand) is causing defoliation and mortality of eastern hemlock (Tsuga canadensis (L.) Carrière) in the eastern United States. The objectives of this study were to quantify changes in tree-ring width and wood anatomy for trees that survived adelgid …
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Differential Canopy Leaf Flushing and Site Nitrogen Status Facilitate Invasive Species Establishment in Temperate Deciduous Forest Understories
… (black locust), and <em>Pinus </em>spp<em>./Tsuga canadensis</em> (pine/hemlock). Measures of understory light availability post-leaf expansion were significantly higher under quaking aspen than other canopies with the exception of black locust and white ash. Significant differences in …
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Forest Dynamics Of Two Multi-Aged Hemlock-Mixed Mesophytic Forests In The Northern Cumberland Plateau, Kentucky
<p>Tsuga canadensis (eastern hemlock) is a foundation species that performs a unique ecological role within the Appalachian mixed mesophytic forest of the eastern United States. However, the non-native hemlock woolly adelgid (HWA; Adelges tsugae Annand), a novel invasive colonizer, is significantly …
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Soil Respiration and Related Abiotic and Remotely Sensed Variables in Different Overstories and Understories in a High Elevation Southern Appalachian Forest
… under consideration were an eastern hemlock (Tsuga canadensis L. Carriere) dominated overstory, a hardwood overstory with little to no understory, a mountain laurel (Kalmia latifolia L.) dominated understory, and a cinnamon fern (Osmundastrum cinnamomeum (L.) C.Presl) dominated understory. …
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Vegetation distribution and site relationships in an Appalachian oak forest in southwest Virginia
… types. Stands dominated by Acer saccharum or Tsuga canadensis occurred mostly in relatively cool, moist conditions at mid to upper elevations, while most stands dominated by Liriodendron tulipifera were in moist locations at lower elevations. Results indicate that shifts in the composition of …
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Leveraging the Landsat Archive to Track Understory Evergreen Shrub Expansions in the Coweeta Basin, North Carolina
… parasitica) and hemlock woolly adelgid (Adelges tsugae), have permanently altered the overstory canopy of Appalachian forests by causing the dramatic die-offs of two ecologically significant tree species, American chestnut (Castanea dentata) and eastern hemlock (Tsuga canadensis). These canopy …
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Factors associated with Atlantic white -cedar seedling recruitment on microtopographic and landscape scales, Brown Mill Pond, Rye, New Hampshire
… red spruce (Picea rubens) and eastern hemlock (Tsuga canadensis) dominated the understory and were expected to replace cedar over successional time.</p>
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Interactive effects of hemlock mortality and nitrogen availability on nutrient pools and fluxes in the southern Appalachian Mountains
… remain poorly understood. Eastern hemlock (Tsuga canadensis) exerts strong control on nitrogen (N) dynamics, and its loss due to infestation by the hemlock woolly adelgid (Adelges tsugae) is expected to affect nutrient dynamics in impacted stands. I evaluated the potential for variation in N …
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Pre-release Evaluation of Laricobius osakensis Montgomery and Shiyake (Coleoptera: Derodontidae), a Potential Biological Control Agent for the Hemlock Woolly Adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), in the Eastern United States
Hemlock woolly adelgid, Adelges tsugae Annand, is an invasive pest threatening eastern (Tsuga canadensis (L.) Carrière) and Carolina hemlock (T. caroliniana Englem.) forests in the eastern US. A new predator, Laricobius osakensis Montgomery and Shiyake, has been found in association with A. tsugae …
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Biological Studies and Evaluation of Scymnus Coniferarum, a Predator of Hemlock Woolly Adelgid from Western North America
The hemlock woolly adelgid (HWA), Adelges tsugae Annand, is an invasive pest of eastern hemlock, Tsuga canadensis (L.) Carriere and Carolina hemlock Tsuga caroliniana Englem. in the eastern United States. A newly reported beetle predator for HWA, Scymnus (Pullus) coniferarum Crotch (Coleoptera: …
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The relationship between dominant forest mycorrhizal type and the belowground mycobiome of the sugar maple and eastern hemlock
… maple (Acer saccharum) and eastern hemlock (Tsuga canadensis) were identified, measured and harvested across four sites, Mont-Écho, Mégantic National Park, Lac-des-Plages, and the Station de biology des Laurentides. I characterized the root and soil fungal communities of maple and hemlock via …
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Studies on the Subterranean Activity of Laricobius spp. (Coleoptera: Derodontidae) using 3D X-ray Analysis and Three Imidacloprid Soil Application Techniques
The hemlock woolly adelgid (HWA) Adelges tsugae (Annand) (Hemiptera: Adelgidae), has spread throughout most of the range of eastern hemlocks, Tsuga canadensis (L.) and the entire range of Carolina hemlocks, Tsuga caroliniana (Engelman) in eastern North America. Forest managers often implement an …
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Laboratory rearing, establishment, subterranean survivorship, and thermal requirements of Laricobius spp. (Coleoptera: Derodontidae), biological control agents released for Adelges tsugae (Hemiptera: Adelgidae)
The hemlock woolly adelgid (HWA) (Adelges tsugae [Annand]) (Hemiptera: Adelgidae) is a non-native lethal pest to eastern hemlock (Tsuga canadensis [L.] (Pinales: Pinaceae), and Carolina hemlock (Tsuga caroliniana [Engelmann]) (Pinales: Pinaceae). In the early 2000's, a robust biological control …
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Abundance Of Songbirds In Eastern Hemlock Stands Following Chemical Treatment For Hemlock Woolly Adelgid
… the invasive Hemlock Woolly Adelgid (Adelges tsugae [hereafter, HWA]) began to spread west across the hemlock stands of the Eastern U.S. killing a significant number of Eastern Hemlock (Tsuga canadensis). While chemical treatments, primarily with the active ingredient imidacloprid, have been …
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