Riparian Ecosystem Response To Hemlock Woolly Adelgid Adelges Tsugae Induced Eastern Hemlock Tsuga Canadensis Mortality In The Great Smoky Mountains National Park Usa

Download Riparian Ecosystem Response To Hemlock Woolly Adelgid Adelges Tsugae Induced Eastern Hemlock Tsuga Canadensis Mortality In The Great Smoky Mountains National Park Usa full books in PDF, epub, and Kindle. Read online Riparian Ecosystem Response To Hemlock Woolly Adelgid Adelges Tsugae Induced Eastern Hemlock Tsuga Canadensis Mortality In The Great Smoky Mountains National Park Usa ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!

Riparian Ecosystem Response to Hemlock Woolly Adelgid (Adelges Tsugae) Induced Eastern Hemlock (Tsuga Canadensis) Mortality in the Great Smoky Mountains National Park, USA

Author : Misty Dawn Huddleston
Publisher :
ISBN 13 :
Total Pages : 134 pages
Book Rating : 4.:/5 (793 download)

DOWNLOAD NOW!

Book Synopsis Riparian Ecosystem Response to Hemlock Woolly Adelgid (Adelges Tsugae) Induced Eastern Hemlock (Tsuga Canadensis) Mortality in the Great Smoky Mountains National Park, USA by : Misty Dawn Huddleston

Download or read book Riparian Ecosystem Response to Hemlock Woolly Adelgid (Adelges Tsugae) Induced Eastern Hemlock (Tsuga Canadensis) Mortality in the Great Smoky Mountains National Park, USA written by Misty Dawn Huddleston and published by . This book was released on 2011 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: An invasive insect, hemlock woolly adelgid (HWA), has initiated widespread hemlock decline and mortality in the Great Smoky Mountains National Park (GSMNP). Riparian hemlock mortality impacts on vegetative and aquatic systems of first-order, headwater streams were evaluated. Reference sites for this study were representative of the best available conditions within the GSMNP, with initial stages of HWA presence. Impacted sites were defined as areas with over 90 percent hemlock mortality. Impacted streams had decreased canopy coverage and increased light availability. Residual red maple, yellow birch, and sweet birch capitalized on the loss of hemlock, with increases in relative basal area and species importance values. Rosebay rhododendron responded with increased density and height at impacted sites, thereby preventing woody regeneration. Since long-term regeneration and post-mortality canopy recruitment are limited, alterations of vegetative composition and structure in the stream riparian zone are expected. A seasonal assessment (Sept. 2009 -- March 2010) of aquatic impacts revealed increased diurnal variation in stream temperature and exhibited cooler temperatures during the colder months than reference streams. Impacted streams exhibited greater amounts and larger size classes of large woody debris (LWD). Higher concentrations for several nutrients, including silicon, sodium, potassium, magnesium, chlorine, and copper were detected in impacted streams than detected in reference streams. Impacted streams were characterized by higher pH and increased acid neutralization capacity, while reference streams exhibited nitrate concentrations three times higher than impacted stream concentrations. Reference streams were experiencing the initial stage of HWA-induced defoliations, increasing stream nitrate concentrations, while impacted sites had levels suggesting nitrate concentrations have returned to pre-infestation levels. A seasonal assessment of macroinvertebrates found species diversity, abundance, and taxa richness were not affected by hemlock mortality. Impacted streams had a lower density of Chironomidae and Ephemeroptera when compared to reference streams, while Pleuroceridae snails were virtually eliminated at impacted stream sites. Reference streams were dominated by the collector/filter functional feeding group (FFG), while impacted streams were dominated by the scraper FFG. Hemlock mortality induced by the presence of HWA has resulted in short-term impacts to vegetative and aquatic dynamics in stream riparian areas of the Great Smoky Mountain National Park.

Impacts of Hemlock Woolly Adelgid on Tsuga Canadensis Forest Communities in Great Smoky Mountains National Park, USA

Author : Kurt J. Krapfl
Publisher :
ISBN 13 :
Total Pages : 83 pages
Book Rating : 4.:/5 (666 download)

DOWNLOAD NOW!

Book Synopsis Impacts of Hemlock Woolly Adelgid on Tsuga Canadensis Forest Communities in Great Smoky Mountains National Park, USA by : Kurt J. Krapfl

Download or read book Impacts of Hemlock Woolly Adelgid on Tsuga Canadensis Forest Communities in Great Smoky Mountains National Park, USA written by Kurt J. Krapfl and published by . This book was released on 2010 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tsuga canadensis (L.) Carr. (eastern hemlock), a long lived and shade tolerant coniferous tree species native to eastern North America, is currently threatened by the hemlock woolly adelgid ( Adelges tsugae Annand, HWA). This exotic, invasive insect poses a serious threat to T. canadensis stands throughout their native range. The loss of this unique tree species is often coupled with numerous ecological consequences. HWA-induced mortality has exceeded 95% in some forest types, and will likely continue to decimate T. canadensis populations in the coming years. Shortly after HWA was found in Great Smoky Mountains National Park (GSMNP), long-term monitoring plots were established across a gradient of T. canadensis associated forest communities to monitor HWA impacts and stand decline. Our objectives were to (1) determine how T. canadensis populations have changed in conjunction with HWA infestation, and (2) document how HWA has affected vegetative community dynamics following five to six years of infestation in GSMNP.

Preparing for the Onset of Hemlock Mortality in Great Smoky Mountains National Park

Author :
Publisher :
ISBN 13 :
Total Pages : 107 pages
Book Rating : 4.:/5 (71 download)

DOWNLOAD NOW!

Book Synopsis Preparing for the Onset of Hemlock Mortality in Great Smoky Mountains National Park by :

Download or read book Preparing for the Onset of Hemlock Mortality in Great Smoky Mountains National Park written by and published by . This book was released on 2006 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: Currently the Hemlock Woolly Adelgid (Adelges tsuga) is spreading across forests in eastern North America, causing the decline and mortality of the eastern hemlock and the Carolina hemlock. Investigation into the impact of hemlock mortality on ecosystem processes has only recently begun and is not yet fully understood. The loss of hemlock from riparian forests in Great Smoky Mountains National Park (GSMNP) could reasonably be expected to result in significant alterations to stream environments. The goal of this study was to assess the influence of riparian hemlock stands on stream conditions and estimate possible impacts from hemlock loss in GSMNP. I paired hardwood-and hemlock-dominated streams that were similar in topography, geology, land use, and disturbance history using Geographic Information Systems (GIS) analysis and statistical techniques. I then monitored each stream pair for water temperature, nitrate concentrations, pH, and discharge over eleven months. I found that differences between hemlock- and hardwood-dominated streams could not be explained by dominant forest type alone; the presence of hemlock or hardwood riparian forest does not appear to exert a consistently dominant signal on measured conditions of headwater streams in GSMNP. The variability in the results suggests that other landscape variables, such as the influence of understory Rhododendron species, may exert more control on stream conditions than differences between hemlock and hardwood canopies. For example, Rhododendron was found to reduce light levels reaching the forest floor and streambeds in both hemlock- and hardwood- dominated forest stands. Evidence from recent peer-reviewed literature suggests that short-term stream condition impacts from forest disturbances can be severe. However, research also indicates that conditions can return to pre-disturbance levels within five to ten years. In GSMNP, the return to long-term stability of stream conditions after hemlock mortality will depend on the type of replacement species and how quickly the replacement species can establish in disturbed sites. There is evidence that deciduous hardwood species are most likely to replace hemlock. The results of this study suggest that hemlock and hardwood stream conditions are similar in GSMNP. Therefore, if hardwood species are able to replace hemlock in GSMNP and streams are able to recover from short term impacts, the long term impacts from hemlock mortality on stream conditions will be minimal. However, the presence of Rhododendron in riparian hemlock forests in GSMNP may prevent hardwood species from effectively replacing hemlock, which could hinder the return to long-term stability.

Eastern Hemlock Forests

Author : Jeffrey S. Ward
Publisher :
ISBN 13 :
Total Pages : 36 pages
Book Rating : 4.:/5 (319 download)

DOWNLOAD NOW!

Book Synopsis Eastern Hemlock Forests by : Jeffrey S. Ward

Download or read book Eastern Hemlock Forests written by Jeffrey S. Ward and published by . This book was released on 2004 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Xylem Transport Models Optimize Effectiveness of Systemic Insecticide Applications for Controlling Hemlock Woolly Adelgid (Adelges Tsugae)

Download Xylem Transport Models Optimize Effectiveness of Systemic Insecticide Applications for Controlling Hemlock Woolly Adelgid (Adelges Tsugae) PDF Online Free

Author : Chelcy R. Ford
Publisher :
ISBN 13 :
Total Pages : 16 pages
Book Rating : 4.3/5 (91 download)

DOWNLOAD NOW!

Book Synopsis Xylem Transport Models Optimize Effectiveness of Systemic Insecticide Applications for Controlling Hemlock Woolly Adelgid (Adelges Tsugae) by : Chelcy R. Ford

Download or read book Xylem Transport Models Optimize Effectiveness of Systemic Insecticide Applications for Controlling Hemlock Woolly Adelgid (Adelges Tsugae) written by Chelcy R. Ford and published by . This book was released on 2010 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hemlock woolly adelgid (HWA, Adelges tsugae Annand) is causing widespread decline and mortality of eastern hemlock trees (Tsuga canadensis (L.) Carr.). Stem injection of insecticide is widely used as a control measure, but its effectiveness depends on individual tree hydraulic characteristics. Recent work has shown that eastern hemlock daily water use is exponentially related to tree diameter, with smaller-diameter trees using significantly less water than largerdiameter trees. In this study we modeled daily water use for 20 eastern hemlock trees across a range of diameters. Based on expected daily water use and, thus, potential xylem transport of insecticide, we applied a dosage estimated to achieve a lethal and uniform xylem sap concentration of imidacloprid to half the trees (xylem transport treatment), and treated the remaining half based on the manufacturerrecommended dosage (MFR treatment), which is a linear function of tree diameter. At 4 and 56 weeks after treatment, we assessed all trees for the presence or absence of new shoot growth and live HWA population density. We found that both treatment dosages significantly reduced live HWA populations; however, 4 weeks after treatment, live HWA population density was 32 percent lower (LSMEANS) on xylem transport treatment trees compared with MFR treatment trees (treatment by time interaction, P = 0.006). Both treatment dosages also significantly increased the proportion of new shoot growth; however, over time xylem transport treatment trees had a significantly greater increase in new shoot production compared with MFR treatment trees. We conclude that dosages based on a xylem transport model not only significantly improved tree health more than the trees receiving the current recommended dosage, but also caused greater reductions in the live HWA population. Improving treatment dosages would reduce treatment cost, nontargeted effects, and would allow land managers to treat a greater number of trees.

City promenade Deventer, elke stap waard

Author :
Publisher :
ISBN 13 :
Total Pages : 36 pages
Book Rating : 4.:/5 (73 download)

DOWNLOAD NOW!

Book Synopsis City promenade Deventer, elke stap waard by :

Download or read book City promenade Deventer, elke stap waard written by and published by . This book was released on 1976 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Life History of Hemlock Woolly Adelgid, Adelges Tsugae Annand, on Eastern Hemlock, Tsuga Canadensis (L.) Carriere

Author :
Publisher :
ISBN 13 :
Total Pages : 76 pages
Book Rating : 4.:/5 (224 download)

DOWNLOAD NOW!

Book Synopsis Life History of Hemlock Woolly Adelgid, Adelges Tsugae Annand, on Eastern Hemlock, Tsuga Canadensis (L.) Carriere by :

Download or read book Life History of Hemlock Woolly Adelgid, Adelges Tsugae Annand, on Eastern Hemlock, Tsuga Canadensis (L.) Carriere written by and published by . This book was released on 2007 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies were conducted in 2005 and 2006 at Baxter Orchard, Great Smoky Mountains National Park, Tennessee to optimize survival of Sasajiscymnus tsugae (St) (Sasaji and McClure) released as eggs on eastern hemlock, Tsuga canadensis (L.) Carriere, for biological control of Adelges tsugae (HWA) Annand. Studies investigated annual abundance and seasonality of HWA lifestages, weekly field and laboratory survival of St, and survival of St egg cohorts of various ages and densities. HWA was determined to be bivoltine on eastern hemlock in Tennessee with an aestivation period between July and October. Lifestages preferred as food by St were present from February through June with peak abundance ca. late March. Weekly survival of St placed in the field and laboratory as eggs was investigated. Less than 10% of St eggs placed in the field between 8 February to 22 March survived because of freezing field temperatures. Survival rose to 30-40% on 30 March and persisted at that level until 7 June, when survival decreased below 10% due to scarcity of food. Studies were conducted to investigate the effect of St egg density on survival of St. Four densities of St eggs (50, 100, 150, and 200 eggs/container) were placed in the field and laboratory. In the laboratory, survival was higher for lower densities of St eggs, implying cannibalism increases with density. Three egg age classes (0-2, 3-5, and 6-8 days old) were used to test the effect of St egg age on survival. St in field cages showed poor survival, likely due to freezing temperatures. However, the oldest (6-8 day) age class showed significantly greater survival in the field than the younger age classes. The two oldest age classes showed significantly greater survival than the youngest (0-2 day) age class in the laboratory. Results of multiple studies over two years support the release of St eggs to enhance biological control efforts against HWA. Studies showed St established as eggs in the field could successfully develop into adults. Survival of St from egg releases is highest when St eggs are released between late March and May, in low densities, and in older age classes.

Predicting Infestations of Hemlock Woolly Adelgid (Adelges Tsugae) in Great Smoky Mountains National Park, Tennessee/North Carolina, USA

Download Predicting Infestations of Hemlock Woolly Adelgid (Adelges Tsugae) in Great Smoky Mountains National Park, Tennessee/North Carolina, USA PDF Online Free

Author : Snider Scott F.
Publisher :
ISBN 13 :
Total Pages : 61 pages
Book Rating : 4.:/5 (592 download)

DOWNLOAD NOW!

Book Synopsis Predicting Infestations of Hemlock Woolly Adelgid (Adelges Tsugae) in Great Smoky Mountains National Park, Tennessee/North Carolina, USA by : Snider Scott F.

Download or read book Predicting Infestations of Hemlock Woolly Adelgid (Adelges Tsugae) in Great Smoky Mountains National Park, Tennessee/North Carolina, USA written by Snider Scott F. and published by . This book was released on 2004 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Benefits and Risks of Imidacloprid-based Management Programs for Hemlock Woolly Adelgid

Author : Elizabeth Paige Benton
Publisher :
ISBN 13 :
Total Pages : 206 pages
Book Rating : 4.:/5 (974 download)

DOWNLOAD NOW!

Book Synopsis Benefits and Risks of Imidacloprid-based Management Programs for Hemlock Woolly Adelgid by : Elizabeth Paige Benton

Download or read book Benefits and Risks of Imidacloprid-based Management Programs for Hemlock Woolly Adelgid written by Elizabeth Paige Benton and published by . This book was released on 2016 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hemlock woolly adelgid, Adelges tsugae (Annand) (HWA) (Hemiptera: Adelgidae), has caused widespread decline of eastern hemlock, Tsuga canadensis (L.) Carriére. This collaborative retrospective analysis with Great Smoky Mountains National Park (GRSM) provides research-based management guidance on imidacloprid treatments and nontarget risks to aquatic systems. Imidacloprid and olefin concentrations were assessed in foliage from different diameter at breast height (DBH) size hemlocks 4 -- 7 yr post-imidacloprid treatment. Imidacloprid concentrations were below the LC50 [lethal concentration] for HWA, but olefin was above the LC50 4 yr post-treatment. HWA populations were suppressed, and hemlock canopies were healthy. Treatment efficacy can last up to 7 yr post-treatment. Hemlocks from the larger (61 and 76 cm) size classes generally had higher concentrations of imidacloprid and olefin. Concentration data from foliage of different size hemlocks were used to develop a model to optimize dosages based on tree diameter. Smaller ( 30 cm) and larger ( 63 cm) hemlocks can be given lower imidacloprid doses, while maintaining > 80% HWA mortality in hemlocks. Impacts to stream water quality and aquatic macroinvertebrates were assessed in ten streams in hemlock conservation areas. Water samples were collected upstream and downstream from conservation areas and in nearby control streams. Imidacloprid was present in seven downstream locations in concentrations from 28.5 to 379 ppt, which is below USEPA aquatic life benchmarks. Aquatic macroinvertebrate bioassessments were conducted at downstream and upstream locations, and downstream baseline data were available. Diversity measures at downstream samples did not vary from those at upstream and baseline samples. Imidacloprid treatments did not negatively affect aquatic macroinvertebrate communities. Imidacloprid treatments suppress HWA populations for up to 7 yr. Dosages can be optimized based on the DBH size of the hemlock. Imidacloprid risks to aquatic systems for this HWA management program were minimal and within USEPA benchmarks.

Invasive Species in Forests and Rangelands of the United States

Author : Therese M. Poland
Publisher : Springer Nature
ISBN 13 : 3030453677
Total Pages : 455 pages
Book Rating : 4.0/5 (34 download)

DOWNLOAD NOW!

Book Synopsis Invasive Species in Forests and Rangelands of the United States by : Therese M. Poland

Download or read book Invasive Species in Forests and Rangelands of the United States written by Therese M. Poland and published by Springer Nature. This book was released on 2021-02-01 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book describes the serious threat of invasive species to native ecosystems. Invasive species have caused and will continue to cause enormous ecological and economic damage with ever increasing world trade. This multi-disciplinary book, written by over 100 national experts, presents the latest research on a wide range of natural science and social science fields that explore the ecology, impacts, and practical tools for management of invasive species. It covers species of all taxonomic groups from insects and pathogens, to plants, vertebrates, and aquatic organisms that impact a diversity of habitats in forests, rangelands and grasslands of the United States. It is well-illustrated, provides summaries of the most important invasive species and issues impacting all regions of the country, and includes a comprehensive primary reference list for each topic. This scientific synthesis provides the cultural, economic, scientific and social context for addressing environmental challenges posed by invasive species and will be a valuable resource for scholars, policy makers, natural resource managers and practitioners.

The Effect of Hemlock Woolly Adelgid Infestation on Water Relations of Carolina and Eastern Hemlock

Author :
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (656 download)

DOWNLOAD NOW!

Book Synopsis The Effect of Hemlock Woolly Adelgid Infestation on Water Relations of Carolina and Eastern Hemlock by :

Download or read book The Effect of Hemlock Woolly Adelgid Infestation on Water Relations of Carolina and Eastern Hemlock written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In North America, hemlock woolly adelgid (HWA; Adelges tsugae Annand) is an exotic insect pest from Asia that is causing severe decimation of native eastern hemlock (Tsuga canadensis (L.) Carr.) and Carolina hemlock (Tsuga caroliniana Engelm.). Extensive research has been committed to the ecological impacts and potential control measures of HWA, but the exact physiological mechanisms that cause tree decline and mortality are not known. Eastern and Carolina hemlock may be reacting to infestation in a manner similar to the response of Fraser fir (Abies fraseri (Pursh.) Poir.) to infestation by balsam woolly adelgid (BWA; Adelges picea Ratz.). It is known that Fraser fir produces abnormal xylem in response to BWA feeding. This abnormal xylem obstructs water movement within the trees, causing Fraser fir to die of water-stress. In this study, water relations within 15 eastern and Carolina hemlock were evaluated to determine if infestation by HWA was causing water-stress. Water potential, carbon-13 isotope ratio, stem conductivity, and stomatal conductance measurements were conducted on samples derived from those trees. In addition, branch samples were analyzed for possible wood anatomy alterations as a result of infestation. Pre-dawn branch water potential (Î ̈) measurements were more negative in infested hemlock than in non-infested trees. Carbon isotope ratios (normalized Î ́13C vs. VPDB) of the branches were more positive for infested trees, while stomatal conductance (gs) was lower in infested trees. These results indicate that infested eastern and Carolina hemlock are experiencing drought-like symptoms. Wood anatomy of the branches provided evidence that infested hemlocks are experiencing abnormal wood production in the xylem.

Landscape Ecology in Theory and Practice

Author : Monica G. Turner
Publisher : Springer Science & Business Media
ISBN 13 : 0387216944
Total Pages : 353 pages
Book Rating : 4.3/5 (872 download)

DOWNLOAD NOW!

Book Synopsis Landscape Ecology in Theory and Practice by : Monica G. Turner

Download or read book Landscape Ecology in Theory and Practice written by Monica G. Turner and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: An ideal text for students taking a course in landscape ecology. The book has been written by very well-known practitioners and pioneers in the new field of ecological analysis. Landscape ecology has emerged during the past two decades as a new and exciting level of ecological study. Environmental problems such as global climate change, land use change, habitat fragmentation and loss of biodiversity have required ecologists to expand their traditional spatial and temporal scales and the widespread availability of remote imagery, geographic information systems, and desk top computing has permitted the development of spatially explicit analyses. In this new text book this new field of landscape ecology is given the first fully integrated treatment suitable for the student. Throughout, the theoretical developments, modeling approaches and results, and empirical data are merged together, so as not to introduce barriers to the synthesis of the various approaches that constitute an effective ecological synthesis. The book also emphasizes selected topic areas in which landscape ecology has made the most contributions to our understanding of ecological processes, as well as identifying areas where its contributions have been limited. Each chapter features questions for discussion as well as recommended reading.

The Effect of Hemlock Woolly Adelgid Infestation on Water Relations of Carolina and Eastern Hemlock

Author : Laura Newman Walker-Lane
Publisher :
ISBN 13 :
Total Pages : 61 pages
Book Rating : 4.:/5 (32 download)

DOWNLOAD NOW!

Book Synopsis The Effect of Hemlock Woolly Adelgid Infestation on Water Relations of Carolina and Eastern Hemlock by : Laura Newman Walker-Lane

Download or read book The Effect of Hemlock Woolly Adelgid Infestation on Water Relations of Carolina and Eastern Hemlock written by Laura Newman Walker-Lane and published by . This book was released on 2009 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: introduced pest species, host response, tsuga canadensis, tsuga caroliniana, adelges tsugae.

Prioritizing Eastern Hemlock (Tsuga Canadensis) for Secondary Imidacloprid Treatment Against the Invasive Hemlock Woolly Adelgid (Adelges Tsugae) in Shenandoah National Park

Download Prioritizing Eastern Hemlock (Tsuga Canadensis) for Secondary Imidacloprid Treatment Against the Invasive Hemlock Woolly Adelgid (Adelges Tsugae) in Shenandoah National Park PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 29 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis Prioritizing Eastern Hemlock (Tsuga Canadensis) for Secondary Imidacloprid Treatment Against the Invasive Hemlock Woolly Adelgid (Adelges Tsugae) in Shenandoah National Park by :

Download or read book Prioritizing Eastern Hemlock (Tsuga Canadensis) for Secondary Imidacloprid Treatment Against the Invasive Hemlock Woolly Adelgid (Adelges Tsugae) in Shenandoah National Park written by and published by . This book was released on 2016 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shenandoah National Park (SNP) contains over 20,000 eastern hemlocks (Tsuga canadensis); a foundation species in the southern Appalachian Mountains. Hemlock is shade-tolerant and retains a dense needle canopy year-round, creating a unique microclimate providing habitat for many species. The decline in eastern hemlock from hemlock woolly adelgid (Adelges tsugae; HWA) infestation has negative implications for the overall function of forest ecosystems. The effect of slope aspect and time since imidacloprid insecticide treatment on crown health change and diameter growth of eastern hemlock in SNP was quantified. Data was compared from hemlock trees located on southeastern (SE) and northwestern (NW) aspects at sites that were either treated two, five or eight years ago. Trees at control sites received no treatment. Change in crown health was significantly affected by aspect and time since treatment (p

Modeling The Effects Of The Hemlock Woolly Adelgid On Carbon Storage In Northern New England Forests

Author : Jeffrey John Krebs
Publisher :
ISBN 13 :
Total Pages : 126 pages
Book Rating : 4.:/5 (18 download)

DOWNLOAD NOW!

Book Synopsis Modeling The Effects Of The Hemlock Woolly Adelgid On Carbon Storage In Northern New England Forests by : Jeffrey John Krebs

Download or read book Modeling The Effects Of The Hemlock Woolly Adelgid On Carbon Storage In Northern New England Forests written by Jeffrey John Krebs and published by . This book was released on 2014 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hemlock woolly adelgid (HWA, Adelges tsugae Annand) is an invasive insect that threatens to eradicate native eastern hemlock (Tsuga canadensis (L.) Carr.) across the eastern United States. In southern New England and southern Appalachian forests, HWA-induced hemlock mortality has impacted carbon (C) flux by altering stand age, litter composition, species composition, and coarse woody debris levels. However, no one has examined how total C storage and sequestration may be impacted by these changes. Further, while projections are that HWA will ultimately infest hemlock across its entire geographic range, the majority of studies have been limited to southern New England and Appalachian forests where HWA infestation has been ongoing. To address these gaps, we examined how HWA might alter C dynamics in northern New England forests using the Forest Vegetation Simulator (FVS) and Forest Inventory Analysis (FIA) data to model C storage and successional pathways under three different scenarios: preemptive harvesting of hemlock, HWA-induced hemlock mortality, and a control mimicking natural stand development absent of disturbance. Our 150 year simulation showed that, while all treatments differed significantly in C storage in the short term, there was no significant difference in total C stocks between HWA infestation and presalvage treatments by the 75th year. Compared to the control, both simulated treatments resulted in a significant decrease in total C storage, with greater impacts on stands with higher hemlock densities. However, net C losses over the 150 year simulation were significantly higher for the presalvage scenario, indicating that allowing HWA infestation to progress naturally through a stand may result in the least impact to long-term C sequestration for the region's forests.

Assessment of Factors Affecting Establishment of Biological Control Agents of Hemlock Woolly Adelgid on Eastern Hemlock in the Great Smoky Mountains National Park

Download Assessment of Factors Affecting Establishment of Biological Control Agents of Hemlock Woolly Adelgid on Eastern Hemlock in the Great Smoky Mountains National Park PDF Online Free

Author : Abdul Hakeem
Publisher :
ISBN 13 :
Total Pages : 121 pages
Book Rating : 4.:/5 (125 download)

DOWNLOAD NOW!

Book Synopsis Assessment of Factors Affecting Establishment of Biological Control Agents of Hemlock Woolly Adelgid on Eastern Hemlock in the Great Smoky Mountains National Park by : Abdul Hakeem

Download or read book Assessment of Factors Affecting Establishment of Biological Control Agents of Hemlock Woolly Adelgid on Eastern Hemlock in the Great Smoky Mountains National Park written by Abdul Hakeem and published by . This book was released on 2013 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eastern hemlock in the Great Smoky Mountains National Park (GRSM) is threatened by hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae). To manage this invasive pest in GRSM, ca. 550,000 Sasajiscymnus tsugae (Sasaji and McClure) (Coleoptera: Coccinellidae) and 7,857 Laricobius nigrinus Fender (Coleoptera: Derodontidae) have been released. Limited information is available on their establishment in GRSM. To fill this gap, a study was initiated to assess establishment of these predators and their impact on hemlock health. To determine factors affecting establishment of these predators, 65 release sites were sampled from 2008 to 2012. Several factors were evaluated for their association with establishment and recovery of S. tsugae. Predatory beetle release information, topographic features, and temperature data were obtained from GRSM personnel. These factors were evaluated using stepwise logistic regression and Pearson correlation. High resolution digital imagery was used in conjunction with field-conducted tree-health surveys to test association between S. tsugae and tree health. S. tsugae were recovered from 13 of 65 sites (20%); recovery was significantly associated with older release sites which indicates that S. tsugae may require more time to reach readily detectable levels. Regression analysis indicated that establishment was positively associated with the average maximum temperature seven days following release and elevation. Several significant correlations were found between presence of S. tsugae, and year of release, season of release, and temperature variables. These results indicate that S. tsugae should be monitored for establishment for at least five years following releases to enhance knowledge of establishment. Coexistence of three predatory beetles, S. tsugae, L. nigrinus and L. rubidus, was observed on the same hemlock trees. Significant differences between normalized difference vegetation index values and S. tsugae presence was observed. For understory and overstory hemlock, percent crown transparency, percent live crown, and percent branch dieback was also significant with presence of S. tsugae. Coexistence of S. tsugae and L. nigrinus on eastern hemlock may provide prolonged feeding on HWA. Predictive models would assist land managers in selecting appropriate times and sites for future releases. Application of digital imagery could be used to evaluate other natural enemies in forest landscapes.

Spatial, Temporal, and Tri-trophic Distribution of Imidacloprid, Olefin and 5-hydroxy and Their Effect on Hemlock Woolly Adelgid, Adelges Tsugae Annand, (Hemiptera: Adelgidae).

Download Spatial, Temporal, and Tri-trophic Distribution of Imidacloprid, Olefin and 5-hydroxy and Their Effect on Hemlock Woolly Adelgid, Adelges Tsugae Annand, (Hemiptera: Adelgidae). PDF Online Free

Author : Carla Irene Coots
Publisher :
ISBN 13 :
Total Pages : 147 pages
Book Rating : 4.:/5 (842 download)

DOWNLOAD NOW!

Book Synopsis Spatial, Temporal, and Tri-trophic Distribution of Imidacloprid, Olefin and 5-hydroxy and Their Effect on Hemlock Woolly Adelgid, Adelges Tsugae Annand, (Hemiptera: Adelgidae). by : Carla Irene Coots

Download or read book Spatial, Temporal, and Tri-trophic Distribution of Imidacloprid, Olefin and 5-hydroxy and Their Effect on Hemlock Woolly Adelgid, Adelges Tsugae Annand, (Hemiptera: Adelgidae). written by Carla Irene Coots and published by . This book was released on 2012 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extensive mortality of eastern hemlock, Tsuga canadensis (L.) Carrière, resulting from infestation by hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae) (HWA), has occurred throughout the eastern United States. Imidacloprid, a systemic insecticide, is used to control hemlock woolly adelgid. The metabolism of imidacloprid in eastern hemlock produces two metabolites of toxicological interest, olefin and 5-hydroxy. The objectives of this study were to 1.) determine the distribution and persistence of the metabolites in eastern hemlock in the southern Appalachians, 2.) their effect on hemlock woolly adelgid mortality, 3.) assess the tri-trophic movement of these compounds, 4.) evaluate the effects of hemlock woolly adelgid infestation levels on water stress, and 5.) assess the use of near-infrared spectroscopy for predicting imidacloprid concentrations in needle tissue. Imidacloprid and 5-hydroxy concentrations in sap was highest at 12 months post-treatment and in twig and needle tissue was highest at 15 months post-treatment. Imidacloprid was detected through month 36 post-treatment and 5-hydroxy was detected through month 15 post-treatment. Olefin concentrations progressively increased in both sap and twig and needle tissue through month 36 post-treatment. Concentrations of imidacloprid were highest in the bottom stratum of the canopy and lowest in the top stratum. Concentrations of olefin and 5-hydroxy were highest in the top stratum and lowest in the bottom stratum. A significant relationship was found between imidacloprid concentrations > 158 ppb and olefin concentrations > 7 ppb and hemlock woolly adelgid mortality greater than 80% in field studies. In dose-response tests imidacloprid concentrations greater than 131 ppb and olefin concentration greater than 7 ppb were associated with high levels of hemlock woolly adelgid mortality (> 80%). Tri-trophic movement of imidacloprid and olefin was documented through 2 years post-treatment. The highest level of water stress was found in those trees with hemlock woolly adelgid infestation levels greater than 75%. The lowest level of water stress was found in those trees with less than 25% hemlock woolly adelgid infestation levels. Near-infrared spectroscopy results indicate that it can be used to predict concentrations of imidacloprid in needle tissue.