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COVID-19 Updates: CCAPS and the University

NAFIWC Program: 5/28/21

Friday, May 28

All times are listed in Central Daylight Saving time.

 
8:30 a.m. – Business Meeting and Awards

 

9:00 – Concurrent Session 5

Moderator: Sam Ward

This session will cover several different mechanisms by which native and non-native forest insects undergo large scale shifts in their distributions and/or abundances. Presentations will focus on the drivers of invasions (arrival, establishment, and spread), range shifts, and outbreaks. Speakers will highlight the many contributions macroscale ecology (a growing subdiscipline in ecology) has already made to forest entomology, and identify areas in which the diversity of technologies used in macroscale investigations (e.g., remotely sensed and other forms of big data) can be further leveraged and integrated to understand the dynamics of insect populations.

 

Exploiting species-habitat networks to improve wood-boring beetle surveillance in areas surrounding entry-points

Davide Rassati, Manuela Branco, Claudine Courtin, Massimo Faccoli, Nina Feddern, Emily Franzen, André Garcia, Martin Gossner, Mats Jonsell, Matteo Marchioro, Petr Martinek, Alain Roques, Jon Sweeney, Lorenzo Marini

Ever-increasing international trade along with ongoing changes in trade networks is causing an impressive number of forest insect introductions. This trend is particularly evident for wood-boring Coleoptera, especially bark and ambrosia beetles, longhorn beetles, and jewel beetles. Traps baited with attractive lures placed around entry points are commonly used to complement visual inspections and improve chances of intercepting incoming species soon after their arrival. Nonetheless, it is still unclear which are the optimal sites where to set up these traps and how landscape composition can affect the chances of intercepting incoming species. In order to investigate these patterns, we used multi-funnel traps baited with a multi-lure blend in areas surrounding 13 entry-points, which were spread in a number of countries (France, Portugal, Italy, Sweden, Italy, USA, Canada, Switzerland and Czech Republic). Sixteen traps were deployed at each selected site based on a grid of 2 x 2 km defined a priori, with one trap per each cell of the grid. Selected sites covered a gradient of forest cover (from urban-dominated areas to forest-dominated areas). Traps were left in the field for five months and all trapped beetles were identified to species. Linking the structure of native and exotic wood-boring beetle communities to landscape composition at different spatial scales (i.e., within-site and among-sites) it will be possible to understand where exotic species are more prone to establish after their arrival in a new environment, and thus which are the optimal sites where to set up baited traps.

 

Alien forest pest explorer: an online portal for exploring ranges of non-indigenous forest pests and the status of their host tree species

Randall S. Morin, Songlin Fei, Andrew M. Liebhold, Susan J. Crocker

Invasions of damaging non-native forest pests are known to affect growth and mortality of host trees. National forest inventory data collected by the US Forest Service's Forest Inventory and Analysis (FIA) program can be used to quantify the impact of these pest species on host tree abundance as well as host growth and mortality rates. The Alien Forest Pest Explorer (AFPE) has been revamped as a portal for the exploration of spatial data describing the ranges of known damaging non-indigenous forest pests established in the United States and the status and trends in their host tree species. The online, interactive tool includes dozens of forest insects and about 15 species of forest pathogens. This site can be used to view and download maps and pest alerts for each of the forest pests as well as statistics about their host tree species from regional FIA data. The AFPE was designed as a data resource for forest health specialists, foresters, and the public. The home page includes a data dashboard that allows for national/regional examination of the number of pest invaders and host tree densities that are at risks. Additionally, individual data dashboards for the most widely distributed and damaging pests provide for investigation of pest range spread, host tree abundance trends, and host tree growth and mortality statistics. Such results demonstrate how forest pest invasions can profoundly modify forest dynamic processes, resulting in long-term changes in forest ecosystems.

 

Assessing drivers of local range expansion across the invasive range of a high-profile insect pest

Gabriela C. Nunez-Mir, Jonathan A. Walter, Kristine L. Grayson, Derek M. Johnson

Macroscale studies are able to produce useful insights for invasion management, particularly when localized information about the dynamics of specific invasive species is unavailable. Here, we present a macroscale study of the roles of invasion drivers on the local dynamics of a high-profile pest, Lymantria dispar. Specifically, we assessed the relative effects of various anthropogenic and environmental variables on local diffusive spread rates of this high-profile pest across its invasive range in the United States. We applied a Bayesian probabilistic framework to annual gypsy moth trap catch data from 1985 to 2015 in order to determine the probability of gypsy moth establishment in 5 by 5 km quadrats. We then calculated the establishment rate of 8,010 quadrats by measuring the number of years from first detection of L. dispar to the year when probability of establishment was 99% or more in these quadrats. To assess the effects of environmental and anthropogenic variables on each quadrat’s establishment rate, we performed linear mixed-effects regression models for three different sub-regions within the invasive range, plus a range-wide model.  Seasonal temperatures were found to be the primary drivers of local establishment rates across. Furthermore, the effects of some factors waiting times to establishment varied across sub-regions. Our findings describe a hierarchy of factors that influence local range dynamics of a high-profile pest, and describe how these interactions change across the U.S. invasive range, highlighting the utility of macroscale studies.

 

A review of forest disturbance attribution using remote sensing

Arjan J.H. Meddens, Amanda Stahl, Robbie Andrus

Ecological disturbances are an integral component of forest ecosystem dynamics. Remotely sensed data offer a spatially extensive and temporally consistent record over the past several decades (e.g., Landsat 1984 to present) for monitoring disturbances in forest ecosystems. Researchers have developed methods to successfully detect many types of abiotic and biotic disturbances that operate across a range of spatial and temporal scales during the last two decades. Many studies have highlighted that disturbances can be detected with relatively high levels of accuracy (~90%). Far fewer studies have demonstrated methods to accurately attribute detected disturbances to a specific disturbance type, and land managers need to know disturbance type to inform effects on forest dynamics. Our objective was to synthesize studies that report on (semi-) automated forest disturbance attribution using remotely sensed data and/or geospatial analysis. We report on the current state of algorithm development (i.e., methods), evaluation methods, and the accuracy of attribution by disturbance type. Finally, we make recommendations for future directions that will improve automated disturbance attribution.

 

Tree diversity and bark beetle outbreaks in subalpine forests of the Rocky Mountains

Sarah J. Hart

Coincident with recent warm and dry conditions, native bark beetles have killed conifer trees across 22.5 M hectares of forest in the western United States. In the Interior West, much of the tree mortality has been concentrated in subalpine forests, where the mountain pine beetle (MPB; Dendroctonus ponderosae), spruce beetle (SB; D. rufipennis), and western balsam bark beetle (WBBB; Dryocoetes confusus), have caused extensive mortality lodgepole pine (Pinus contorta), Engelmann spruce (Picea engelmannii), and subalpine fir (Abies lasiocarpa), respectively. Given these bark beetle species affect only one or several tree species, a common management goal to mitigate the effects is to promote species diversity. Yet, many stands are composed of a mix of pine, spruce, and fir and it remains poorly understood how tree species diversity affects tree survival in the face of multiple bark beetle outbreaks. Here, I use USFS Forest Inventory and Analysis (FIA) data to examine the effects of diversity on patterns of tree mortality due to MPB, SB, or WBBB activity across subalpine forests. I found the probability of either MPB, SB or WBBB occurring within a stand was greatest when all three hosts were present, but the severity of cumulative bark beetle activity was greatest when only one host was present. In stands with multiple hosts, the co-occurrence of multiple bark beetle species occurred infrequently (ca. 5% of plots), but generally resulted in higher severity infestation. These results highlight the importance of managing forests in the context of multiple bark beetle species.

 

A method for detecting fundamental changes in population dynamics across landscapes and over time

Devin W. Goodsman

I will introduce an approach that enables researchers to confirm that a fundamental change in population dynamics has occurred. This approach will enable researchers to delineate regions in which population dynamics have changed. I will then demonstrate the approach using several historical data-sets of insect abundance collected by the Canadian Forest Service.

Moderator: Brian Aukema

This session highlights forest insect and disease challenges of relevance to Minnesota, the state that was expected to be the host before the meeting went virtual.  This session showcases how state, federal, and university partnerships engage to prioritize and confront forest health challenges whose impact reaches beyond the state’s borders.  This session will highlight basic, applied, and regulatory issues across several forest types in the Great Lakes region.

  • The Minnesota Invasive Terrestrial Plant and Pest Center model: Rob Venette
  •  The search for associational protection in urban forests treating for emerald ash borer:  Dora Mwangola
  • Image analysis homes in on oak wilt pockets in Minnesota: Rachael Dube
  • Resurgence of larch casebearer: Samuel Ward
  • Trichoferis campestris, a new exotic woodborer now found in Minnesota: Grace Haynes
  • A new pest of concern in the state with regulatory implications: elongate hemlock scale: Angie Ambourn

Moderator: Tara Bal

Challenges with new associations between organisms continue to emerge due to multiple factors. Significant ‘exotic’ damaging agents may no longer be coming from a different continent, but with climate change and anthropogenic change, novel encounters will occur, as endemic species respond via range expansion, population dynamics, trophic interaction shifts, or in other ways. Forest pest management has been increasingly balancing efforts between "exotic" and "native" pests, which poses additional challenges for the larger social and political landscape as we develop a better understanding of how species will respond, leading to decisions about how species interactions are mitigated.

  • Eastern larch beetle: celebrating twenty years of outbreak (and counting): Brian Aukema
  • Phenological synchrony between eastern spruce budworm and its host trees increases with warmer temperatures in the boreal forest: Deepa Pureswaran
  • Drivers increasing ticks and tick-borne diseases in North America: Maria Diuk-Wasser
  • Southern pine beetle behavioral shifts through space and time: Steve Clarke
  • Shifting mountain Pine Beetle range and implications of host expansion in naïve forests: Allan Carroll

10:30 – Break

 

11:00 – Concurrent Session 6

Moderator: Scott Salom

Part of our changing world in forestry has been the devastation caused by non-native insects and plant pathogens. While there are literally hundreds of species that could be covered, five species, four of which have a long history of impacting our forest ecosystems and one more recent, are presented here in the context of: 1. Current spread, damage, and impacts; 2. Integrated efforts towards management; and 3. Predicting the aftermath of invasion and success in management. Each pest has had major investment in study, and as a result, demonstrate the challenges that are faced when non-natives flourish in North America attacking trees and other plants with little or no resistance to them. It is suggested that investment into the study and management of forest pests, whether native or non-native, requires urgency as we struggle to maintain healthy native forest ecosystems.

 

European gypsy moth

Tom Coleman

After more than 150 years gypsy moth still dominates forest pest management in the USA. Since the late 1860s, European gypsy moth continues to be a prominent threat to oak-dominated forests in the USA. Cyclical outbreaks continue to impact the eastern part of the country with recent outbreaks occurring in Connecticut, Massachusetts, and Rhode Island (2015 to 2018) and western Virginia (2016 to 2018). In recent years, populations have increased in Michigan and Pennsylvania, necessitating suppression treatments in 2021. Gypsy moth spread from quarantined areas has been limited by an aggressive management program.  The USDA National Gypsy Moth Management Program guides gypsy moth management with four strategies: 1) Suppression, 2) Slow-the-Spread, 3) Eradication, and 4) Regulatory activities. Recent eradication treatments have successfully eliminated outlying populations in several eastern, central, and western states. For 20 years, the National Gypsy Moth Slow the Spread Program, comprised of multiple state and federal agencies and a non-profit foundation, has been the focus of gypsy moth management. Slow the Spread annually monitors tens of thousands of traps and treats hundreds of thousands of acres with mating disruption and biological control strategies, which target newly established populations. The program has successfully slowed the rate of spread of gypsy moth with a comprehensive integrated pest management program. Eradication treatments and an international monitoring program have successfully prevented the establishment of Asian gypsy moth in the USA.

 

Spread, impact and management of hemlock woolly adelgid in eastern North America

Albert Mayfield, Scott Salom, Robert Jetton, Nathan Havill, Rusty Rhea

Seven decades after its initial introduction, the hemlock woolly adelgid (HWA) continues to gain new ground in its persistent invasion of hemlock forests in eastern North America. Although eastern hemlock is not a prized commercial timber species, substantial ecological and aesthetic impacts from HWA are compounded by economic costs associated with property value losses, management efforts, and research. Applications of existing tools and new developments in the areas of biological control, chemical control, silviculture, gene conservation, and host resistance are important near- and long-term components of an integrated management approach to this persistent invasive pest.

 

Protection of ash stands against emerald ash borer with biological control: Recent progress and potential for success

Jian J Duan, Therese Poland, Leah S. Bauer, Roy Van Driesche, Joe Elkinton

Ash trees (Fraxinus spp.) are an important component of both natural forests and urban plantings in the United States and Canada.  However, the unexpected arrival of emerald ash borer (EAB) (Agrilus planipennis Fairmaire) from Asia during the 1990s threatens the persistence of North American ash in mixed hardwood stands.  Despite early efforts by US and Canadian regulatory agencies to eradicate and contain EAB after its discovery in southeast Michigan in 2002, this invasive beetle has spread to 38 U.S. states and five Canadian provinces and has killed hundreds of millions of ash trees in both urban and natural forests.  Although systemic insecticides are now available to control EAB in ash trees, injections are used mainly to protect high-value landscape trees in urban areas.  Introduction and establishment of natural enemies from the pest’s native range (northeast Asia) for biological control provides a viable option for long-term and sustained suppression of EAB in natural forests.  Implementation of biological control for EAB began in 2007 in southern Michigan after APHIS issued permits allowing environmental release of three EAB parasitoid species from China.  These biocontrol agents included two larval parasitoids, Tetrastichus planipennisi (Eulophidae) and Spathius agrili (Braconidae), and an egg parasitoid, Oobius agrili (Encyrtidae).  In 2015, a fourth EAB larval parasitoid, Spathius galinae (Braconidae) from the Russian Far East, was approved for release.  With the help of researchers, land managers, and landowners, EAB parasitoids have been released over 25 EAB-infested states and two Canadian provinces since 2007.  In this presentation, we first briefly review the current EAB biocontrol program that involves introduction and establishment of hymenopteran parasitoids from northeast Asia and then present our most recent findings on the impact of these introduced natural enemies on EAB population growth and ash stand recovery in the aftermath of the initial EAB outbreak.  In particular, we will discuss whether natural enemies (parasitoids) can hold EAB populations to a low enough density to allow ash to regenerate and recover.

 

Status and impacts of laurel wilt disease in North America

John J. Riggins, John P. Formby, Frank H. Koch, Jason A. Smith, Marc Hughes, Adam Chupp, Natalie Dearing, Hannah Bares, Natraj Krishnan, Richard Brown, Kelly Oten, Don Duerr

Laurel wilt is a non-native tree disease that continues to impact native plants of the family Lauraceae in the United States. This disease is caused by an introduced vector (Xyleborus glabratus) and a pathogenic fungal symbiont (Raffaelea lauricola). All North American shrub and tree species in the plant family Lauraceae that have been tested thus far are susceptible. We estimated that over 300 million individual redbay trees (Persea borbonia), or >1/3 of the pre-invasion population, succumbed to the disease within the first 15 years of the invasion. Genetic markers indicated that the vector and pathogen entered North America as a single introduction. We studied the cold temperature ecophysiology of X. glabratus and concluded that less than 1% of sassafras trees in North America occur in a climate cold enough to limit the beetles’ eventual range. With apparent minor limitations on the spread of LWD, trophic cascades in the wake of this devastating invasion are possible. To document the radiating impacts of this disease on invertebrates that rely on hosts within the Lauraceae, we compiled a database of all known invertebrate interactions with North American Lauraceae, which yielded a list of 178 associated invertebrate species, at least 24 of which may suffer substantial declines alongside their lauraceous hosts. Overall, the lack of effective control options and a vector system well-suited to invading new territory in North America have enabled LWD to become one of the most destructive tree diseases on record.

 

Successful biological control of winter moth, Operophtera brumata, in the northeastern United States

Joseph S. Elkinton, George H. Boettner, Hannah J. Broadley, Richard Reardon, Ronald Weeks

Winter moth, Operophtera brumata L., native to Europe, invaded the northeastern United States in the late 1990s, where it caused widespread defoliation of forests and shade trees ranging from 2,270 to 36,360 ha per year between 2003 and 2015 in Massachusetts. In 2005, we initiated a biological control effort based on the specialist tachinid parasitoid Cyzenis albicans, which had successfully controlled winter moth in Nova Scotia in the 1950s and British Columbia in the 1970s. Each year for 14 years, we collected several thousand individuals of C. albicans from British Columbia and released them across widely spaced sites in the northeastern United States. As of 2020 we had established C. albicans at 41 of 44 sites from coastal Maine to southeastern Connecticut. By 2016 winter moth densities (pupae/m2) had declined at least 10-fold at six widely spaced release sites and the decline was coincident with the onset of 10-40% parasitism. At one site where this decline occurred in 2012, winter moth densities have remained low for eight subsequent years. Since 2016, defoliation by winter moth in Massachusetts has been reduced to undetectable levels by aerial survey. DNA sequencing of the CO1 barcoding region of the mitochondrial gene confirmed that all C. albicans reared from winter moth were distinct from flies reared from Bruce spanworm, Operophtera bruceata, the native congener of winter moth. Parasitism was thus the result of the introduced flies from Vancouver Island and not from native flies. As far as we know, winter moth represents the only example of biological control that has succeeded in reducing a major forest defoliator, attacking many tree species, to non-pest status anywhere in the world.

 

Impacts of spotted lanternfly on hardwood trees

Kelli Hoover, Osaiyekemwen Uyi, Emily Lavely, David Eissenstat

Spotted lanternfly (SLF) is a voracious, phloem-feeding planthopper first discovered in N. America in one county in Southeastern Pennsylvania about 6 years ago. There are now 32 PA counties in quarantine and breeding SLF populations in 8 other states, most with state-mandated quarantine zones. SLF adults use transportation corridors as a pathway for long distance spread; they hitchhike on railroad cars, trucks, and in cargo holds of airplanes. SLF is polyphagous in both its native and introduced ranges but has a strong preference for the invasive plant Ailanthus altissima (tree of heaven). In a study using four established hardwood tree species in large enclosures, half that contained Ailanthus and half that did not, SLF developed from egg to adult and produced viable eggs. However, it took adults two weeks longer to begin oviposition in the absence of Ailanthus. This study also allowed us to document host preference by life stage over the course of the season and there was a negative relationship between diameter growth and host preference. In studies using a common garden, red maple, silver maple, and Ailanthus had reduced photosynthesis, stomatal conductance, transpiration and carbohydrate content following moderate or high SLF feeding pressure. Documenting impacts on tree health (growth) in forest ecosystems is a difficult undertaking, in large part because of the unpredictable nature of this pest. SLF nymphs and adults can move long distances during a season that lasts from May through early November. Slowing the spread of SLF is proving to be a major challenge for pest managers.

Moderators: Lia Spiegel, Iral Ragenovich

In the late 1950s and early '60s Balsam woolly adelgid caused significant mortality in both the eastern and Pacific northwestern true fir communities. Almost 50-70 years later it has begun significant range expansion into the interior west, affecting new ecosystems. Changes in length of season and warming temperatures may be influencing populations. In areas where it has been long established, residual host may be growing into a new susceptible stage. There will be no formal presentations in this workshop, rather it will be a conversation about the most current knowledge and research, as well as making recommendations, and identifying research needs.

  • What do we know about BWA phenology and what is still missing?
  • What do we know about environmental effects on BWA, BWA range expansion, and ecological effects of BWA on resources?
  • What do we know about BWA impacts on trees, species susceptibility, and location?
  • What management options (e.g., suppression, genetic resistance, or silviculture) are currently available or needed?

 

As a soil amendment, biochar is useful for sequestering carbon, with other benefits related to its physical structure that increases the retention of H2O and nutrients while reducing soil acidity and nutrient leaching. Biochar treatments can directly impact plant health and improve habitat for beneficial microorganism but can also cause shifts in soil microbial communities. Additionally, some insects show delayed development, decreased fecundity, lowered egg hatch and increased mortality under various application conditions. Such indirect affects need further examination. The session will address direct and indirect effects of biochar on soil properties and biotic communities.

  • Changes in insect communities following biochar applications in restoration projects: Steve Cook
  • Biochar influence on termite populations and communities: Brad Kard
  • Fungal community composition following treatment with soil amendments: Daniel Lindner
  • Impact of biochar on physical and chemical properties of soil: Deborah Page-Dumroese

Moderator: Jeff Garnas

An argument in support of classical biological control of Chinese tallow tree (Triadica sebifera)

 

Comparing the role of propagule pressure in the colonization success of Hylurgus ligniperda and Ips pini

Kevin Chase, D Kelly, AM Liebhold, EG Brockerhoff 

A crucial factor affecting the colonization process of invading species is propagule pressure, the size and frequency of arriving populations. A key determinant contributing to propagule pressure effects on invasion success is the ‘Allee effect’, which is defined as increasing population growth with increasing abundance. We conducted parallel experimental releases using two species of bark beetles, Hylurgus ligniperda in New Zealand and Ips pini in North America, to (i) quantify colonization thresholds, (ii) empirically test for Allee effects, and (iii) assess the role propagule pressure in invasion success. Establishment success was positively associated with release density (i.e., propagule pressure) for both species but colonization success generally occurred at lower densities for H. ligniperda than for I. pini. We discuss the biological characteristics determining colonization success. Our results linking invasion failure to small founding population sizes generally support the theoretical literature on the role of propagule pressure and Allee effects in biological invasions.

 

Amitinol: A possible pheromone component for I. calligraphus that is generated post-release

Brian T. Sullivan, William P. Shepherd

The pine-killing bark beetle Ips calligraphus has been shown to release a two-component aggregation pheromone consisting of the monoterpenes ipsdienol and cis-verbenol; these are produced by attack-initiating males shortly after entering the phloem.  To identify attack-mediating semiochemicals for this species that may have been overlooked in previous research, we investigated beetle olfactory sensitivities using gas chromatography-electroantennographic detection (GC-EAD).  As expected, ipsdienol and cis-verbenol present in volatiles collections of male-initiated gallery entrances produced strong antennal responses; however, a third compound not previously reported in association with I. calligraphus, amitinol, also produced strong responses from antenna of both sexes.  Hindgut extracts of male beetles contained ipsdienol and cis-verbenol but no more than trace amitinol, whereas frass extruded from galleries contained all three compounds. A similar finding was reported for ipsdienol-producing species of Ips in Europe, and these researchers showed that amitinol could arise from rearrangement of ipsdienol under conditions of low pH.  Trapping experiments failed to find behavioral activity for amitinol with I. calligraphus when the compound was presented either with or without the known components of the aggregation pheromone.  The origins of amitinol and its possible role in the chemical ecology of Ips calligraphus and other species of Ips will be discussed.

 

Gene silencing as a novel tool for emerald ash borer management

Flavia Pampolini, Lynne K. Rieske

RNA interference (RNAi) is a naturally occurring cellular immune response triggered by exogenous double-stranded RNA (dsRNA) that induces the RNAi pathway, leading to silencing of genes and disruption of protein function. The sequence complementarity of the RNAi pathway allows for targeted suppression of genes essential for insect survival, which enables development of pest management strategies specific to a given pest species. Manipulating the RNAi pathway can cause mortality in the highly invasive emerald ash borer (EAB), Agrilus planipennis. We found no nontarget effects of dsRNAs targeting the EAB genes hsp, shi and sn-rnp in model insects representing five functional guilds, confirming a high degree of specificity to the target insect. Additionally, we found no effects of the EAB-specific dsRNAs on the classical biological control agents. Effective delivery of the dsRNA is challenging, particularly in systems with long-lived, endophagous insects such as the EAB. Using confocal microscopy we demonstrate uptake, movement, and insecticidal activity of labeled dsRNA in green, F. pennsylvanica, and tropical ash, F. uhdei, through root and/or petiole absorption. Although our findings provide a proof of concept that delivery of dsRNAs through topical or systemic application is feasible, in order to move this technology to the deployment stage practical delivery methods must be fully evaluated. Current efforts are focused on gaining a greater understanding of the spatial and temporal distribution of EAB-specific dsRNAs in ash seedlings.

 

Effects of prescribed fire and forest age on pollinator diversity in the longleaf pine ecosystem

Michael D. Ulyshen, J. Kevin Hiers, Scott M. Pokswinksi, Audrey C. Wilson, Gunnar C. Ohlson, Conor Fair

There is much interest in preserving and restoring the remaining fragments of longleaf pine forest on the southeastern US coastal plain.  This endangered ecosystem is famous for its high diversity of fire-adapted plants and other organisms, but few efforts have been made to describe the associated bee community or to develop management recommendations for conserving this fauna. Results from three studies aimed at addressing these questions will be discussed. The first study found a positive relationship between pyrodiversity (i.e., heterogeneity of burn history on the landscape) and the diversity of both bees and butterflies. It also suggests that high burn frequency over large areas may have a negative effect on these insects. The second study found a higher concentration of ground-nesting bee nests in regularly-burned forests than in forests burned less frequently. The third study found few differences in bee diversity between old-growth and mature secondary longleaf pine forests, suggesting that recovering forests can still support a high diversity of pollinators. In addition to establishing baseline knowledge about the bees of the longleaf pine ecosystem, this work will provide land managers with important information for protecting pollinators throughout much of the southeast.

 

Landscape and local factors driving species richness of longhorned beetles and bees in a fragmented landscape

C.R. Traylor, M.D. Ulyshen, J.V. McHugh

Insect communities respond to a variety of factors, ranging from local habitat conditions to processes operating at a landscape scale. Specific influences may vary between taxa that have different life histories or dissimilar resource requirements. Within forests, the diversity of saproxylic insects is often used as an indicator of overall forest health, and these species facilitate the decomposition of woody debris. In recent years, increased attention has also been given to pollinators in forests. Pollinators can obtain a variety of resources from forests, and they move between forests and other land uses. Yet, how these two groups respond to landscape factors in forests is relatively understudied. Here, we investigate how native longhorned beetle and bee diversity are affected by local forest conditions and landscape context. Longhorned beetles (Coleoptera: Cerambycidae) comprise a diverse family that mostly tracks fresh deadwood resources. Bees (Hymenoptera: Apoidea: Anthophila) are significant pollinators of native trees and forbs. We sampled these insects from forests in Athens, GA, along gradients of both forest age and landscape forest amount. Other local and landscape factors were also measured and included in the analysis. These relationships with species richness will be discussed along with implications for conservation.

12:30 p.m. – Adjourn