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Showing 1 to 20 of 21 for “"eastern hemlock"”.
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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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Abundance Of Songbirds In Eastern Hemlock Stands Following Chemical Treatment For Hemlock Woolly Adelgid
<p>In the 1960’s 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, …
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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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Development and properties of tracheids and their cell wall layers in eastern hemlock (Tsuga canadensis L.)
… 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 aid of a polarizing microscope. In accordance with the cellular structures described …
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The relationship between dominant forest mycorrhizal type and the belowground mycobiome of the sugar maple and eastern hemlock
… of the sugar 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 …
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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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Prey-mediated effects of imidacloprid on Laricobius nigrinus (Coleoptera: Derodontidae) and Sasajiscymnus tsugae (Coleoptera: Coccinellidae), two predators of hemlock woolly adelgid
… tsugae Sasaji and McClure after feeding on hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae). Two methods were evaluated for detecting imidacloprid in hemlock tissues: a commercially available enzyme linked immunoassay (ELISA) kit and a high performance thin-layer …
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The role of olfaction in host-finding by two specialist predators of hemlock woolly adelgid
The hemlock woolly adelgid (HWA), Adelges tsugae Annand (Homoptera: Adelgidae), is forest pest introduced to eastern North America in the early 1950's. Although this pest occurs on both landscape and nursery stock as well as in natural stands of hemlock forest, pesticides are only practical and …
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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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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
… vegetation types 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) …
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Leveraging the Landsat Archive to Track Understory Evergreen Shrub Expansions in the Coweeta Basin, North Carolina
… blight fungus (Cryphonectria 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 …
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Factors associated with Atlantic white -cedar seedling recruitment on microtopographic and landscape scales, Brown Mill Pond, Rye, New Hampshire
… driest community 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
… magnitude of effects 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 …
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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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Biology and Host-Range Testing of <i>Laricobius kangdingensis</i> sp. n. (Coleoptera: Derodontidae), a Newly Discovered Predator of Hemlock Woolly Adelgid, <i>Adelges tsugae</i> Annand (Homoptera: Adelgidae)
… n. (Coleoptera: Derodontidae), a new predator of hemlock woolly adelgid (HWA), <i>Adelges tsugae</i> Annand (Homoptera: Adelgidae) were investigated and compared with that of a related predator of HWA, <i>L. nigrinus</i> Fender. Adults became active in June 2003; the males emerged first and in …
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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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A Multi-scale Analysis of the Potential Impacts of Rapid Climate Change on Forest Lands Managed by the Department of Defense in the US
… warmer climate conditions projected for the northeastern U.S. Cover types characterized by species at the northern end of their ranges (e.g., species associated with oak (Quercus rubra, Q. alba)-hickory (Carya cordiformis) forest) increased in abundance, especially on more xeric sites such as sand …
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