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Sunday 15 January 2017

Asian Longhorned Beetle

Adult Trapping System 

Research Issue

Ways to detect new Asian longhorned beetle (Anoplophora glabripennis) (ALB) infestations, monitor ALB population levels, and verify that eradication has taken place were needed.  Prior to the research reported here, there was no effective way to attract and trap adult ALB.  Monitoring of ALB using ground or tree climbing surveys is labor intensive, highly inefficient, and sometimes ineffective.  The usual approach to monitoring insects was followed to develop pheromone-baited traps because of their specificity and potential distances over which they can operate.  An operationally effective trap to monitor the Asian longhorned beetle has been a goal of the ALB eradication program since the first beetle was found in New York in 1996. Research on reproductive behaviors has shown that more than one pheromone is involved in the process.  The Semio-chemicals involved have been identified but the location of receptors is still unknown.  Compounds have been selected, evaluated and shown to be effective as lures in adult traps.  Further work to improve the trap design is still needed.

Our Research

Antennal receptors
Work to delineate sensory structures on the antennae of male and female ALB, that might be responsive to chemical attractants has been conducted. Antennae have been examined using light microscopy and scanning and transmission electron microscopy, and a number of types of receptors have been identified.

[image:] Adult ALB in trapPheromones and the development of traps 

The goals of this project are to: 1) characterize ALB behavioral responses to two different pheromones, one male produced and one female produced, as potential candidates for monitoring and/or management of this destructive tree pest, 2) to develop an efficient lure and monitoring trap to monitor ALB at low populations. 

Expected Outcomes

An adult trap that can be used to detect ALB at low population levels. 

Research Results

Antennal receptors

The antenna of each sex has 11 segments – a scape, pedicel, and 9 similar annuli that make up the flexible flagellum. Because the scape and pedicel bear few surface structures, it is unlikely that they are involved in chemoreception. The flagellum is covered with dense hairs arranged in broad alternating black and white bands. The hairs are socketed and their surface is uniformly sculptured with fine ridges running along the axis. The hairs measure approximately 8 μm x 55 μm and appear identical to hairs found on the elytra. Three other types of setae are found on the flagellum. Long hairs (10 μm x 250 μm) are located at the junctions of annuli. There are 12-25 of these per segment; their position indicates that they likely function as mechanoreceptors. Somewhat shorter setae (8 μm x 120 μm) are located just proximal to the junction of annuli (20-40 per segment), and several (2-40 per segment) long setae (8 μm x 350 μm) are located in the midregion of each annulus. Their histology indicates that the setae function as mechanoreceptors. To date, there is no evidence of pores or pore canals within the setae that would be indicative of chemoreception.
Several structures have been identified on the flagellum of male and female ALB antennae that may function as chemoreceptors. The terminal annulus of both male and female antennae has at its apex 11-20 basiconic pegs, approximately 2.8 μm in diameter and height. Pores generally are located near the pegs. However, histological examination of the pegs reveals they closely resemble contact chemoreceptors described in other insects. Observations of adult ALB behavior lend support to the hypothesis that these pegs function as contact chemosensilla.
Shields KS, Mikus DR. 2000. A preliminary description of Anoplophora glabripennis antennal sensory receptors. In: Fosbroke SLC, Gottschalk KW, eds. Proceedings, US Department of Agriculture Interagency Research Forum on Gypsy Moth and Other Invasive Species 2000. Gen. Tech. Rep. NE-273. Abstract, p.55

Laboratory and field evaluation in China of potential lure and trap designs 

In 2002, two male-produced volatiles were isolated from ALB that stimulated antennae of both sexes of ALB. The components were synthesized and consisted of an aldehyde (4-(n-heptyloxy)butanal) and an alcohol (4-(n-heptyloxy) butan-1-ol).
Behavioral tests conducted in the laboratory in 2006 showed a significant attraction of virgin female ALB toward the alcohol. In July 2007 and 2008, field trapping experiments using ALB male-produced pheromone were performed in Ningxia province in China. Results showed a significantly higher total trap catch in the pheromone blend-baited traps, followed by traps baited with the pheromone blend + plant volatiles. Alcohol-baited traps caught only females, supporting previous lab results. Coupling plant volatiles with the male pheromone appeared to increase the attractiveness of females to the traps. 
Over the 2012 and 2013 field seasons, a total of 160 flight intercept panel traps were deployed in Harbin, China, which trapped a total of 65 beetles.  In 2012, traps using lures with a 1:1 ratio of the male-produced pheromone components (4-(n-heptyloxy)butanal and 4-(n-heptyloxy)butan-1-ol) designed to release at a rate of 1 or 4 mg/day/component in conjunction with the plant volatiles (-)-linalool, trans-caryophyllene and (Z)-3-hexen-1-ol caught significantly more A. glabripennis females than other pheromone release rates, other pheromone ratios, plant volatiles only, and no lure controls. Males were caught primarily in traps baited with plant volatiles only. In 2013, 10x higher release rates of these plant volatiles were tested, and linalool oxide was evaluated as a 4th plant volatile in combination with a 1:1 ratio of the male-produced pheromone components emitted at a rate of 2 mg/day/component. Significantly more females were trapped using the pheromone with the 10-fold higher 3 or 4 plant volatile release rates compared to the plant volatiles only, low 4 plant volatile + pheromone, and control.  Our findings show that the male-produced pheromone in combination with plant volatiles can be used to detect A. glabripennis. Results also indicate that emitters should be monitored during the field season since release rates fluctuate with environmental conditions and can be strongly influenced by formulation additives.
Meng, P.S.; Trotter, R.T.; Keena, M.A.; Baker, T.C.; Yan, S.; Schwartzberg, E.G.; Hoover, K. 2014. Effects of pheromone and plant volatile release rates and ratios on trapping Anoplophora glabripennis (Coleoptera: Cerambycidae) in China.Environmental Entomology. 43(5): 1379-1388.
Nehme, M.E.; Keena, M.A.; Zhang, A.; Baker, T.C.; Xu, Z.; Hoover, K. 2010. Evaluating the use of male-produced pheromone components and plant volatiles in two trap designs to monitor Anoplophora glabripennis. Environmental Entomology. 39(1): 169-176. 
Nehme, M.E.; Keena, M.A.; Zhang, A.; Baker, T.C.; Hoover, K. 2009. Attraction of Anoplophora glabripennis to male-produced phermonone and plant volatiles. Environmental Entomology. 38(6): 1745-1755. 

Successful Trapping of ALB in the United States

[photo:] Female ALB in trap.Over four years of trap evaluation (2009-2012), 1013 intercept™ panel traps were deployed, 876 of which were baited with 3 different families of lures. The families included lures exhibiting different rates of release of the male A. glabripennis pheromone, lures with various combinations of plant volatiles, and lures with both the pheromone and plant volatiles combined. Overall, 45 individual beetles were captured in 40 different traps. Beetles were found only in traps with lures. In several cases, trap catches led to the more rapid discovery and management of previously unknown areas of infestation in the Worcester county regulated area. Analysis of the spatial distribution of traps and the known distribution of infested trees within the regulated area provides an estimate of the relationship between trap catch and the nearest known infestation source.  Studies continue to optimize lure composition and trap placement.
[photo:] Checking an ALB trap in Massachusetts.The current findings show that traps baited with male beetle pheromones, presented alone or in combination with plant-derived volatile compounds, can be effectively deployed in invaded landscapes to detect beetles. Indeed, the trapping efforts led in some cases to the detection of previously undiscovered beetle infestations in areas that had not yet been surveyed (for example, in Shrewsbury, MA, east of the core of the infestation in Worcester in 2011). Increasing the speed of detection, thus reducing the time available for beetle population growth prior to the initiation of control efforts, has major implications for management. And the use of trapping data to prioritize areas for tree climbing surveys and other interventions appears to have significant potential in this regard.
Traps may also prove useful as a tool for confirming the presence of infested trees in previously surveyed areas.  In several cases over the course of the four-year study, trap captures guided the eradication team to trees with cryptic infestations that had not been detected in earlier surveys. For example, in 2009, two beetles were trapped in Dodge Park, an area where ALB initial surveys had been completed, and on Doyle Street where host trees are scarce and scattered. Guided by these trap catches, two new infested trees were found in Dodge Park. Similarly, in 2010 and 2011, a total of 4 females were trapped in baited traps hung on the same tree on Lansing Avenue near Indian Lake and finally after surveying the area both years after the beetles were trapped, a small boxelder across the street was discovered that is thought to be the source of the beetles. Furthermore, the identification of some of these infested trees triggered expansion of the regulated boundary to the west. (It is worth noting, however, that in some cases, the source of beetles found in our traps has not been determined despite targeted surveys in the surrounding areas).  
This study complemented and provided a check on the applicability of the findings of both previous and current work in China where higher beetle densities facilitate investigation of lure composition.  Earlier studies conducted in high beetle density areas in China indicated a combination of male-produced pheromone and plant volatiles were most effective at drawing ALB into traps (e.g., Nehme et al. 2010).  These findings are consistent with the overall pattern observed in the current study, though the relatively small number of beetles caught prevents the statistical verification of this pattern.  While the current findings show that baited traps can be effective in trapping beetles in an invaded landscape, more work remains to be done to optimize the lures used. 
[image:] Graph of distance to nearest known ALB infested tree in metersAn important goal in optimizing the use of ALB traps is to determine the best spacing for the traps.  In the urban/forested landscapes where ALB infestations have been found placing traps in a simple gridded array will not work because trees are unevenly distributed and traps work best when placed on open grown or edge trees.  The current findings provide a preliminary estimate to use for trap spacing of 85 + 21 m based on the average distance a beetle traveled in one season from the closet known infested tree to the trap (see figure).  It should be noted that these distance estimates can only provide a distance to the possible tree the beetle emerged from and not how close to the trap the beetle had to be before it would orient toward the lure.  Also, the current data support only limited conclusions in this regard, because of the relatively small number of beetle captures, potential effects of wind direction and strength, human aided movement (e. g. moving infested work or beetles riding on vehicles) and because not all infested trees on the landscape are known. 
The traps are hung in the lower canopy of trees from June until September. The solution in the cup at the bottom is a saturated salt solution with a couple drops of dish washing liquid added, which will safely kill the beetles that fall into it.  The traps are hung out of reach and checked once every two weeks.  We again this year have traps deployed in Worcester, MA and some of the adjacent towns to assist the eradication program and to continue refining the lures.
Nehme ME, Trotter RT, Keena MA, McFarland C, Coop J,  Hull-Sanders H, Meng P, C.M. De Moraes, M.C. Mescher, and Hoover K. 2014. Development and evaluation of a trapping system for Anoplophora glabripennis in the United States.  Environ. Entomol. 43:1034-1044.

Identification of a sex specific trail pheromone

[photo:] Male ALB choosing which branch to take to follow the female’s trailWe discovered a pheromone produced by female ALB that is laid down as a trail when they walk across the surface of the tree. Four chemicals were isolated and identified from the trails of virgin and mated females when they are about 20 days old, which corresponds to the timing of when they are fertile. These compounds are attractive to males, but repel virgin females, probably to help females avoid competition for a mate. This provides us with more information about the series of complex behaviors, as well as chemical and visual cues and signals that facilitate mate location and help the male find the female initially on a huge tree and to relocate her in order to guard her from other males. These compounds have been synthesized and could potentially be useful in managing the invasive beetles in the field using a lure and kill method. 

Hoover, Kelli; Keena, Melody; Nehme, Maya; Wang, Shifa; Meng, Peter; Zhang, Aijun. 2014. Sex-specific trail pheromone mediates complex mate finding behavior in Anoplophora glabripennis. Journal of Chemical Ecology. 40(2): 169-180. 

 

Research Participants

Principal Investigators

  • Maya Nehme, Department of Environmental Engineering, Faculty of Agricultural and Veterinary Sciences, Lebanese University, Dekwaneh, Beirut
  • Kelli Hoover, Pennsylvania State University, Professor 
  • Peter Meng, Pennsylvania State University, recent Master’s Student
  • Kelli Hoover, Pennsylvania State University, Professor 
  • Aijun Zhang, USDA Agricultural Research Service, Invasive Insect Biocontrol and Behavior Laboratory Research Chemist
  • Melody Keena, US Forest Service- Northern Research Station Research Entomologist
  • Talbot Trotter, III, US Forest Service- Northern Research Station Research Ecologist
  • Kathleen Shields, US Forest Service- Northern Research Station Research Entomologist (Retired) 

Research Funding and Support Sources

  • Alphawood Foundation of Chicago (Funding 2006-present)
  • USDA Animal Plant Health Inspection Service Plan Protection and Quarantine, Center for Plant Health Science and Technology, Buzzards Bay, MA (supplies 2009 and staff 2010-11) 
  • US Forest Service, State and Private Forestry Northeastern Area, Technology & Methods Development    10-CA-11420004-316 (Funding 2011-13) 
  • Horticultural Research Institute (funding 2012)
  • Massachusetts Department of Conservation and Recreation and Agriculture and Markets (gaining permissions)
  • New York Agriculture and Markets (staff 2010)
  • ALB eradication programs in New York City and Worcester (climbers and information)

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/alb/risk_detection_spread/adult_trapping_system/

Asian Longhorned Beetle

Detection and Survey Tools 

[photo:] Scientist uses acoustic detector to locate ALB-infested treesResearch Issue

Anoplophora glabripennis (ALB, Coleoptera: Cerambycidae), was inadvertently introduced into North America, probably in solid wood packing material associated with imports from eastern China or Korea where it is native The first established population in North America was discovered in New York in 1996.  Infestations have since been found in Illinois, New Jersey, Massachusetts, and Ontario, Canada.  Because of its wide host range and its ability to attack and eventually kill apparently healthy trees, ALB has the potential to cause serious economic and ecological damage nationwide.  Therefore, eradication programs under the direction of the USDA Animal and Plant Health Inspection Service (APHIS) and the Canadian Food Inspection Agency (CFIA) have been underway at all North American infested sites since their discovery.  Intensive surveys are conducted to locate all infested trees, which are then cut down and chipped. 
The eradication program relies on accurate location and destruction of all infested trees.  Infested trees can be difficult to identify during the initial stages of infestation.  Early signs of attack include oviposition pits, sap leakage from egg-laying sites, and frass or boring dust produced by larval feeding and expelled through the egg-laying site.  Initial attacks occur in the upper branches of trees where cryptic oviposition pits are particularly difficult to see.  Later, circular exit holes made by emerging adult beetles, and crown dieback become evident.  However, by the time exit holes are visible, beetles have already emerged and potentially spread to other trees. 
Currently, locating infested trees is based entirely on visual surveys.  Initially, surveys were conducted from the ground using binoculars; however, in 1999 ground-based surveys were supplemented using bucket trucks and tree climbers, revealing many more infested trees.  Nevertheless, visual surveys are not very effective and are extremely costly, labor intensive, and time consuming.  More sensitive means of detection are necessary to locate newly infested trees.  A simple detection device that can be easily operated by a single user from the ground and which is highly sensitive to very low levels of beetles present inside upper branches of trees, would greatly facilitate survey and detection and enhance the eradication program. 
The adults of several insect species including many bark beetles and woodborers produce sounds that are used in mate attraction and recognition. Audible sounds are also produced incidentally by moving and feeding activities of wood-infesting insects within trees or logs.  Vibrational cues may be exploited for detection of insects hidden within their hosts through the use of acoustic technology.  Acoustic monitoring has been used for decades to detect insects including termites and pests in stored products.  Development of practical methods for acoustic detection of this beetle requires the solution of technical problems involving transmission of resonant frequencies in wood and high background noise levels in the urban environments where most infestations have occurred. Rapid advances in computing and electronics have allowed for the development of automated acoustic-based recognition systems.  Such systems could be designed for hand held use for the detection and recognition of pest species.  In many instances it is sufficient to be able to detect the presence of insect pests without precise species identification.  However, to impose regulatory action against quarantined pests it is important to accurately detect and identify the quarantined species.  

Our Research

The goal of this project was to develop a field deployable, easily used, hand-held instrument that could detect the presence of ALB larvae at ports of entry and potential areas of infestation.  The instrument would perform the analyses necessary to distinguish ALB feeding vibrations from those of other similar insects that could also be infesting trees and wood products.   
Studies were conducted in collaboration with researchers at the Oak Ridge National Laboratory.  We recorded feeding sounds from ALB larvae as well as larvae of several native woodborers including: cottonwood borer, linden borer, locust borer, red oak borer, sugar maple borer, and whitespotted sawyer in order to identify unique acoustic signal descriptors associated with ALB.
We developed filter algorithms that match sounds of feeding larvae in both trees and cut logs.  The algorithms were incorporated into a data collection and analysis system and installed on a laptop computer.  The analysis of the data is completed in real time and results are displayed on the computer’s screen in real time.  We compared acoustic vibration data for ALB larvae feeding in trees of different species, at different distances from the sensor, and for different sizes and ages of ALB larvae.  

Expected Outcomes

The results of our research may lead to the development of a field deployable, easily used, hand-held instrument that could detect the presence of ALB larvae at ports of entry and potential areas of infestation.  This would ultimately lead not only to improved applications for detection of important, hidden insect pests but also to new insights into insect behavior. 

Research Results

Overall, feeding sounds of woodborer larvae were quite similar but ALB feeding sounds do have unique signal descriptors.  Older larvae feed deeper in the sapwood of the tree and their feeding produced larger amplitude vibrations.  The amplitude of larval feeding vibrations diminished with distance between the sensor and the larva.  In trees, vibrations appeared to move most strongly with the wood grain.
The acoustic detection system was successful in detecting the presence of infestations in sample logs and in trees in natural settings in China.  We recorded ALB larvae feeding in infested elm, poplar, and willow trees in China.  Recordings have been of larvae that were feeding at distances of up to 7 m away from the sensor.  A Generation II system was assembled at ORNL that can be used in the field.  The Generation II system incorporates the same data acquisition and analysis hardware and software on a “belt-worn” format computer.  “Belt-worn” computers are much smaller, lighter, and more portable than laptop computers and are carried in a mesh “belt” worn around the user’s waist.  This Generation II system paves the way to produce an inexpensive, hand-held instrument for detection of the ALB. 

Research Participants

Principal Investigators:

  • Robert A. Haack, US Forest Service Northern Research Station Research Entomologist 
  • Therese M. Poland, US Forest Service Northern Research Station Research Entomologist 

Research Partners:

  • Glenn Allgood, Oakridge National Laboratory
  • Cyrus Smith, Oakridge National Laboratory

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/alb/risk_detection_spread/detection_survey_tools/

Asian Longhorned Beetle

Effects and Impacts

[photo:] Tree specialist in bucket truck inspects tree branches up close in New York CityALB has the potential to cause extensive economic impact given its ability to infest and eventually kill hardwood trees in more than 15 plant families. If not eradicated, ALB will negatively affect forest product industries, maple syrup production, tourism and recreation, as well as trees in urban, rural and natural ecosystems. Research is underway to quantify the eradication costs of ALB in the United States and other countries that have become infested with ALB, and to quantify the tree species composition of the urban forests in the United States and use that information to predict potential risk or loss due to ALB.

Our Research

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/alb/effects_impacts/

Asian Longhorned Beetle

Control and Management 

[photo:] Insecticide is delivered to tree using mauget injection systemEfforts are underway to develop environmentally safe, biologically-based methods to control ALB that do not entail destruction of the entire infested tree.  The potential for using nematodes and several pathogens has been evaluated.  Systemic insecticides have also been evaluated as a method to kill adults and larvae, and as a method to prevent infestation of trees within the quarantine zones.

Our Research

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/alb/control_management/

Asian Longhorned Beetle

Biology and Ecology 

[image:] Collage of ALB damageAnoplophora glabripennis (ALB) is native to China and the Korean Peninsula.  In China, it is considered a major pest of several deciduous broadleaf tree species and causes severe damage from 21°--43°N latitude and from 110°--127°E longitude. The primary host trees of ALB in China include species of Acer (maple), Populus (poplar), Salix (willow), and Ulmus (elm), and it is reported to feed on more than 24 genera of hardwood trees. Eggs are laid beneath the bark and early larval instars feed under the bark, whereas later instars enter the wood. In China, ALB takes 1 or 2 years to complete development depending on the timing of adult emergence; later emerging adults lay eggs that may not hatch until spring a year later and some larvae require a chill period after they reach full size. 
Northern Research Station scientists have been conducting research on biology and ecology of ALB since 1999.  This research has been directed toward providing the biological basis for predicting potential dispersal, developmental phenology, predicting population dynamics at low population levels, and attack rates in different environments.  Also, methods to increase the availability of insects for use in research have been developed. 

Our Research

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/alb/biology_ecology/

Asian Longhorned Beetle

Risk, Detection, and Spread 

[photo:] Crates lined up for inspectionEarly detection of new ALB infestations is critical to slow their spread and reduce the time needed for eradication.  Accurate delimitation of the area infested by ALB is also critical for regulatory officials who establish quarantine boundaries and eradication areas.  Survey crews rely on signs and symptoms to detect ALB-infested trees: adult exit holes, oviposition pits, sawdust from larval feeding, sap oozing from limbs, and branch die-back.  Further improvements are still needed in methods to monitor ALB population levels and to verify that eradication has been successful .  In addition, regulatory officials need to know the origin of the ALB infestations to better target their inspection efforts at ports-of-entry to prevent future introductions and to understand better the behavior and biology of existing ALB infestations.

Our Research

Last Modified: 09/04/2009



For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/alb/risk_detection_spread

Asian Longhorned Beetle

[image:] Adult Asian longhorned beetleAnoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), referred to as the Asian longhorned beetle (ALB), is one of the more recently introduced non- native invasive species with potential to become a major pest in the United States.  It was first discovered in the New York City area in August 1996, and additional infestations were discovered in the Chicago area (July, 1998) and Jersey City, NJ (October, 2002), and Toronto and Vaughan, Ontario, Canada (September, 2003).  In August 2008, a large infestation was found in Worcester, MA and 66 square miles are now (2009) under quarantine with more likely to be added as the area is surveyed.  As of 2009, established populations of ALB have also been found in Austria (2001), France (2003, 2004, 2008), Germany (2004, 2005), and Italy (2007).  In the United States, the USDA Animal and Plant Health Inspection Service (APHIS) has implemented an eradication program whereby all trees with signs of beetle infestation (oviposition pits or exit holes) are removed and destroyed. The eradication program for ALB has greatly impacted the local areas where this beetle has been found because of the removal of thousands of trees, which has cost millions of dollars. The United States has implemented stricter trade regulations to prevent further introductions. If the established populations of ALB are not eradicated, the beetle could threaten the maple sugar industry, fall-foliage tourism, natural ecosystems, recreational areas, and many beloved backyard and street trees. 
Little was known about ALB when it was first discovered in the United States, however, scientists have since provided considerable new information on detection and control methods now used by USDA APHIS in their ALB eradication program. Although APHIS is progressing in its goal to eradicate ALB, additional improvements in control methods are still needed to reduce costs, improve efficiency, and ensure successful eradication.

 Our Research

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/alb/

Emerald Ash Borer


[photo:] Adult emerald ash borers emerging from exit holes.The emerald ash borer (EAB), Agrilus planipennis(Coleoptera: Buprestidae), was discovered as the cause of extensive ash tree (Fraxinus spp.) decline and mortality throughout southeastern Michigan in June 2002. Evidence suggests that A. planipennis first entered Michigan from China in the 1990s, presumably from solid wood packing materials used to transport manufactured goods. EAB has subsequently been found in at least 24 US states and 2 Canadian provinces as of March 2016. (View distribution map.) Spread of EAB results from EAB flight and human transport of infested ash firewood, logs, lumber, and nursery stock. 
To limit human-assisted spread of this pest from areas infested with EAB, states imposed quarantines and regulations on the transport of ash trees and ash wood products. Federal quarantines were imposed by USDA Animal and Plant Health Inspection Service and the Canadian Food Inspection Agency. 

 Our Research

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/eab/

The Gypsy Moth, Lymantria dispar (L.)


The Gypsy Moth, Lymantria dispar (L.)

[image:] Gypsy moth larvaThe gypsy moth (GM) is an invasive nonnative insect with larvae that feed voraciously on the foliage of many North American plants. GM caterpillars prefer oaks and aspens, but do not eat conifer needles unless they are starving. Preferred hosts are concentrated in the Northeast, Midwest, and southern Appalachians and Ozarks. GM was introduced about 130 years ago near Boston and has chomped its way through New England and Mid-Atlantic regions; the current “invasion front” stretches from North Carolina across to Minnesota. 
At the invasion front, trees are being attacked for the first time and are usually completely defoliated, sometimes for a second time if they re-foliate. Behind the front, GM live at various densities, and populations can quickly increase (or “erupt”) every 5 to 10 years. Defoliation reduces trees’ growth, vigor, and resistance to biotic and abiotic stressors and cause direct mortality. Although less than 20% of the trees in most forests will die, tree mortality can be heavy in some places. Tree mortality reduces timber value; residential costs are associated with GM defoliation and nuisance— caterpillar hairs cause allergic reactions in humans and caterpillar “frass” (essentially excrement) can literally rain down from trees.
Fortunately, in forests behind the invasion front, several of the biological controls that were introduced at various times generally keep GM populations at reasonable numbers, although outbreaks do occur. Chemical insecticides are no longer used for spraying, only biocontrol agents such as the lepidoptera-specific bacterium Bacillus thuringiensis (Bt); a viral pathogen (Gypchek); and mating disrupters are now mostly used. For over 100+ years, the GM has been the focus of intensive study as federal, state, and academic entomologists, ecologists, and other scientists have worked to control and understand this voracious pest and stop its spread. 
Much of the biology and behavior of GM has been studied and reported in the scientific literature and many control measures have been developed; they will be discussed in the sections below. Currently, Northern Research Station research focuses on newer goals — (1) slowing the spread of this insect into new susceptible habitats; (2) developing and improving biological controls; and (3) determining what factors influence eruptions or outbreaks. 

 Our Research

Last Modified: August 17, 2015

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/gm/

Hemlock Woolly Adelgid

Hemlock woolly adelgid nymphs settled at the base of hemlock needles.  Note that these young adelgids have just begun to form the white wool around the edges.The hemlock woolly adelgid, Adelges tsugae(HWA), a tiny sap-sucking insect related to aphids, is causing widespread death and decline of hemlock trees in the eastern United States. This species, native to Asia and the Pacific Northwest, was first noted in the eastern United States in 1951 in a park in Richmond, VA. The genotype present in eastern North America originated in Japan and was probably introduced unintentionally with ornamental Japanese hemlocks. It initially spread slowly until the late 1980s when it reached natural forests and began to kill trees by the thousands. It has since spread into at least 17 states from the Smoky Mountains to southern Maine. The HWA has few natural enemies in eastern North America, and our native eastern hemlock species are neither resistant to nor tolerant of adelgid feeding. Without these natural defenses, the adelgid poses a very serious threat to the sustainability of eastern hemlocks. 
Research on the HWA by scientists at the Northern Research Station and their cooperators is focused on outlining the scope of the problem and identifying management options. Specifically, work on the HWA falls into four inter-related areas.
  • Risk, Detection, and Spread: Understanding if, when, and how the adelgid is likely to infest new forests provides critical information for managers as they work to identify areas that are at high risk and allows managers to prioritize control efforts based on where and when those efforts will be most effective. 
  • Biology and Ecology: Work is underway to improve our understanding of the biology of the HWA, including its life history, reproduction, and ecological role.  The data can provide the basis for evaluating where, when, and under what conditions the adelgid is likely to cause damage, as well as what basic mechanisms may act to control populations.  
  • Control and Management: Data collected by evaluating adelgid biology, ecology, landscape risk, and spread are used to develop control and management techniques.  These techniques include the development of resistance to the adelgid in our native eastern and Carolina hemlocks.  Control and management efforts also include the development of appropriate natural enemies as biological controls.  Although chemical controls, such as the use of systemic insecticides and horticultural oil, have proven effective in controlling adelgids in yards, gardens, and parks, the cost, effort, and environmental consequences associated with these chemicals make them inappropriate for forests at the landscape scale.
  • Effects and ImpactsAssociated with efforts to control and manage the adelgid are efforts to understand the nature and magnitude of adelgid impacts on eastern forests.  Current work includes efforts to identify those impacts both directly through the loss of hemlock species and indirectly through changes in the structure and biodiversity of eastern forests. This information can be used to evaluate the severity and nature of the threat to eastern forests posed by the HWA.             
For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/hwa/

Nun Moth


[image:] Adult nun mothsThe nun moth, Lymantria monacha (nun moth), is closely related to gypsy moth in appearance and behavior.  Nun moth is not known to be established in North America, is an Eurasian pest of conifers (spruce, fir, larch and pine) that poses an ever-present threat of being accidentally introduced because of its biology and behavior.  It is distributed over most of Europe, across Siberia and the Russian Far East, within a band between lat 43º to 57º N. It is a major pest in Central and Eastern Europe and southeastern Siberia, as well as Spain.  For example, in Poland, during the period 1987-94, the nun moth caused enormous tree losses on more than 6.3 million ha.  Its establishment in North America would be disastrous because of its polyphagous feeding habits, ability to colonize new habitats, and capacity to be spread rapidly by vagile adults. Adults are readily attracted to artificial lights and have been observed in Russian Far East ports.  Nun moth has a high potential to be transported via commerce because, although eggs are normally laid in tree back crevices they also could be deposited in crevices on containers, pallets, ships, etc.  Regions of highest risk in North America, based on host plant availability and climate, include some 70,000 ha of western forests west of the Cascade Range, high-elevation spruce/fir/pine, and northeastern North America.  We have been studying this insect in quarantine since 1996 to proactively develop tactics to prevent its introduction and establishment in North America and to provide eradication options should it be introduced.  

The proactive research done under quarantine

For further details log on website :
https://www.nrs.fs.fed.us/disturbance/invasive_species/nun_moth/

What Is the Difference Between a Straight Bar & Curl Bar?

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What Is the Difference Between a Straight Bar & Curl Bar?
A young woman lifting a straight bar Photo Credit prudkov/iStock/Getty Images
The main differences between a straight bar and curl bar are in their weight, shape and the hand positioning you can utilize when using them for different exercises. These are two of the most common pieces of exercise equipment you will find in a gym that has a resistance training section. These bars can sometimes be used interchangeably, which is beneficial if the particular bar you want to use or the bar type you want to use is unavailable; however, there are some things to consider when using the bars as substitutes for each other.

Weight

Straight bars and curl bars are available is a variety of weights. This is important in determining how much weight you are actually lifting. The total amount is the bar weight added to the amount of plate weights you've mounted on the bar. An Olympic straight bar typically weighs 45 lbs., but smaller versions are available that weigh 35 lbs. A curl bar usually weighs 25 to 30 lbs. The discrepancy in weight is mainly due to the curl bar being smaller in length than the straight bar.

Shape

What Is the Difference Between a Straight Bar & Curl Bar?
A curl bar allows for a more natural hand position. Photo Credit Comstock/Comstock/Getty Images
As its name implies, the straight bar, also called a barbell, is a cylindrical rod with a straight shape. On each end of the barbell are two attached rods that are also cylindrical and straight. This is the area of barbell where the weight plates are put on to increase the resistance. The curl bar is smaller in size and has a cambered “W” shape. On each end of the cambered bar are straight rods where the weight plates are added to increase resistance.



Hand Positioning

The reason for the difference in the two bars ultimately boils down to how the hands are positioned on the bars. Because a standard barbell is straight, you can assume either an overhand or underhand grip. The angle of your wrists with a standard barbell is straight; however, your wrists are slightly rotated when using a curl bar meaning your wrists will be slightly angled. A curl bar allows you to grip with an underhand based “natural” grip with your wrists slightly supinated, or turned out. You can also use an overhand based “reverse” grip on the curl bar with your wrists slightly pronated, or turned inward.

Considerations

The curl bar is traditionally used for exercises that work smaller muscle groups such as your bicep and triceps. These muscles normally require less weight than exercises that use the straight bar such as the chest and legs. Because the curl bar already weighs less, it makes it possible to select a weight between 25 lbs. and 45 lbs. when performing exercises that target the smaller muscles. Also realize that the curl bar has a more natural hand position for exercises that require bending of the elbows. The straight bar increases the amount of torque in the wrists because you must actively hold your wrists in a straight position when they want to naturally turn outward or inward depending on the exercise. This can lead to pain or injury in the wrists if you are unaccustomed to using a straight bar or have poor wrist strength.
For further information log on website :
http://www.livestrong.com/article/447669-what-is-the-difference-between-a-straight-bar-curl-bar/

Difference Between an Energy Bar and a Granola Bar

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Difference Between an Energy Bar and a Granola Bar
Granola bars can be a good source of energy. Photo Credit ian600f/iStock/Getty Images

If you become tired and have difficulty focusing between meals, consider eating a snack to boost your energy levels. Granola bars and energy bars are small, portable snacks that give you fuel during the day. No clear criteria define the differences between granola bars and energy bars. Some energy bars contain granola, and granola bars can be excellent sources of energy during the day. Energy bars sometimes contain higher levels of protein, vitamins and minerals than granola bars. The major nutritional differences between energy bars and granola bars depends on the brand you choose.

Sources of Energy

Energy bar manufacturers often claim their products improve physical performance or boost mental alertness. The sources of energy from an energy bar are the same as from any other food product: fats, protein and carbohydrates. Nutrition experts measure the amount of energy found in a food by calculating its calorie content. Both energy bars and granola bars contain nutrients that boost your calorie intake, giving your body energy

Ingredients

The ingredients of energy bars and granola bars often overlap. In general, the primary ingredient in granola bars is a granola made from rolled oats, puffed rice or other grains. Some energy bars contain rice crisps, rolled oats and toasted oats. Sugar syrups, oils, fruit pastes and other sticky materials hold the grains together in a bar form.

Protein

One primary difference between granola bars and energy bars is their protein levels. Regular granola bars contain approximately 1 g of protein per bar. Energy bars, on the other hand, may contain 10 to 20 g of protein per serving. Common sources of energy bar protein include gelatin, collagen, milk, soy or eggs. Some energy bars also contain nuts or seeds that boost their protein content.

Vitamins and Minerals

Many energy bar manufacturers claim their products provide your body with important nutrients needed to boost your energy levels. Some energy bars are fortified with vitamins and minerals, such as calcium, iron, vitamin C, vitamin K, B vitamins and zinc. Plain granola bars sometimes contain small amounts of vitamins and minerals but may not be fortified with extra nutrients. In general, getting important nutrients from energy and granola bars is not as healthy as eating a variety of fruits and vegetables.

Considerations

Many of the nutritional differences between granola bars and energy bars depend on the manufacturer. Energy bars tend to contain relatively high protein levels. Granola bars, on the other hand, tend to be lower in calories and protein. Products may also differ in size, which affects nutrient content per serving. Carefully check the nutritional labels of energy bars and granola bars to determine their nutrient content before purchasing.
For further information log on website :
http://www.livestrong.com/article/548682-difference-between-an-energy-bar-and-a-granola-bar/

Advantages and Disadvantages of Fasting for Runners

Author BY   ANDREA CESPEDES  Food is fuel, especially for serious runners who need a lot of energy. It may seem counterintuiti...