Source: PURDUE UNIVERSITY submitted to
SAFEGUARDING DOMESTIC LANDSCAPES FROM EXOTIC AND ESTABLISHED PESTS THROUGH THE ADOPTION OF BEST MANAGEMENT PRACTICES IN PRODUCTION AND URBAN LANDSCAPES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0153341
Grant No.
(N/A)
Project No.
IND011461
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2010
Project End Date
Sep 30, 2015
Grant Year
(N/A)
Project Director
Sadof, C.
Recipient Organization
PURDUE UNIVERSITY
(N/A)
WEST LAFAYETTE,IN 47907
Performing Department
Entomology
Non Technical Summary
Unlike agronomic crops that are valued for their food, ornamental plants are valued for their appearance. As such ornamental plants can be damaged when pests harm their health or simply detract from their aesthetic appeal. For this reason plant producers in the greenhouse and nursery industry have a very low tolerance for pests and apply pesticides frequently to preserve the economic value of their plants. Landscape managers and urban foresters are caught in the middle between demands for healthy looking plants and the public aversion to pesticides. Pest management tactics must meet specific management objectives if they are to achieve goals while minimizing pesticide use. In domestic nurseries and greenhouses we work with them produce an economically viable plant for the domestic market. In an established landscape substantially higher amounts of injury can be tolerated. Our research for producers and landscapes targets these different management goals. The threat of exotic invasive pests and the identification of the ornamental industry as a conduit for their spread have provided a new set of management contexts with a zero tolerance for new pest introductions. Internationally, there is a need to work offshore in exporting countries to provide management approaches that reduce the flow of pests into the US on imported plants. Domestically, there needs to be a tracking system in place that can trace these plants through the production chain in the event of an interception in order to intercept infested plants before they are spread throughout the continent. For this reason we work with regulatory agencies and industry both here and abroad to develop approaches for intercepting pests and controlling their spread in an economically efficacious manner. Early detection of exotic wood boring pests by urban foresters can trigger timely management responses that can greatly reduce the extent of damage to city trees. For example, the early detection of the Asian longhorned beetle in Chicago resulted in the death of thousands of trees and not the hundreds of thousand likely to be lost in Worcester, Massachusetts where detection occurred later. Despite the importance of early detection, it is unreasonable to expect urban foresters to maintain a vigilant surveillance of the 70% of forest susceptible to these pests. Foresters need some kind of tool to focus their efforts on trees that are most susceptible to borers. Although most street tree inventories include a ranking for tree vigor, these schemes were primarily developed to help forest managers predict and plan for tree maintenance activity. We simply do not know the relationship between these rankings and the probability of attack and mortality of trees by boring insects. Understanding the relationship between standard arborist rankings of tree vigor and the probability that a borer will attack a tree will pave the way for development of new early detection tools. Through early detection of new invasive species, control programs will be more capable of preventing the catastrophic loss of trees to these pests.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1242199113030%
2052199113010%
2112199113030%
2152199113030%
Goals / Objectives
Objectives: 1.Identify tactics for reducing pest problems in production and landscape systems that improve plant quality while minimizing pesticide inputs. 2.Develop systems for reducing pest abundance in offshore ornamental productions systems and tracking the movement of pests through the domestic and off-shore supply chain. 3.Develop tools to early detection and rapid response of exotic invasive pests of urban forests. Outputs: 1. New pest management tactics will be produced. 2. New systems for reducing pest abundance in domestic and offshore production will be produced. 3. Monitoring tools will be developed to detect invasive species.
Project Methods
1. Our research seeks to develop new tactics for controlling pests that rely less on pesticide inputs than other management techniques which reduce the susceptibility of plants to pests. These techniques begin by determining how practices used by growers and landscape manager influence pest abundance. This assessment is conducted at multiple trophic levels. First we determine how a practice affects the pests by directly altering its capacity to grow and reproduce. Then we examine how these changes affect the capacity of beneficial insects to attack and regulate pest populations. Once the impacts are determined, we work with our collaborators to determine how a practice influences plant growth, marketability and the economic viability of a production operation. Our investigations range from the identifying mechanisms of host plant resistance, to examining the impacts of fertilization practices, weed control, landscape design, and type and frequency of pesticides used. 2. We will work with domestic and offshore growers to produce a clearly defined set of best management practices (BMPs) that will reduce the abundance of key pests and pesticide use during production and post harvest processing. This will be accomplished by adopting Hazard Analysis Critical Control Point (HACCP) principles to identify key problems and potential control points throughout the supply chain. 3. Currently, urban foresters routinely conduct street tree inventories to help them develop plans to manage hazards resulting from failing trees and to improve forest health. During these inventories, arborists record subjective rankings of tree condition and/or pest incidence; however the extent of insect attack is rarely quantified. Moreover, we do not know how the assessment of tree vigor provided by city foresters during these inventories relates to the likelihood of woodborer infestation. To detect exotic borers, foresters need a tool to focus their efforts on trees whose degraded condition make them most susceptible to these pests. The goal of this work is to explore the relationship between standard arborist rankings of tree vigor and the probability that a borer will attack a tree, to pave the way for development of new early detection tools. We will first survey and validate current assessment schemes of tree vigor used by arborists and correlate these schemes with the incidence of borer infestation. Secondly, we will use a validated assessment scheme of tree vigor to measure ash decline in urban areas with and without EAB. We will then determine if the subjective measures of tree vigor and pest incidence on which assessment schemes are based correlate with an objective measure of tree stress and other predictors of tree stress. Finally, through participatory research involving the private sector and state and local agencies, we will evaluate the capacity of arborists to use existing and proposed ranking schemes to detect invasive borers. 3.

Progress 10/01/10 to 09/30/15

Outputs
Target Audience:My audience included urban forester, landscape producers, the nursery industry and home horticulture. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The PI was awarded a Fulbright grant to study non-target effects of pesticides at the Politecnic Institure in Madrid, Spain from Jan 2014- April 2014. How have the results been disseminated to communities of interest?Papers have been published in journals. The PI has gone to trade shows around the country to promote the use of tools to protect trees against emerald ash borer. The PI has also used this information to inform topic selection for a national webinar series that he runs called Emerald Ash Borer University What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? 1. Over the course of this project we published a series of papers about pests in Costa Rican Dracaena boutnd for export to the US. These provided the justification for modifiying regulations that would expand the market for producers following our pest managment protocols. 2. We developed pest threshold for managing pests of maples that reduced the use of pyrethroid insecticides and spider mite problems. 3. We developed a web based cost calculator in use that helps cities make decisions about managing their ash trees. 4. We developed a set of apps that help homowners reduce pesticide use by helping them identifying the pest before applying insecticide

Publications

  • Type: Journal Articles Status: Awaiting Publication Year Published: 2015 Citation: Peterson D. L., Duan J.J., Yaninek J.S., Ginzel MD1, C. S. Sadof. 2015. Development of Larval Agrilus planipennisi (Coleoptera: Buprestidae) and Fitness of Tetrastichus planipennisi (Hymenoptera: Eulophidae) in Blue Ash (Fraxinus quadrangulata) and Green Ash (F. pennsylvanica) Environmental Entomology DOI: http://dx.doi.org/10.1093/ee/nvv122 In press December 2015
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Prado, J., A. R. Witte, S. D. Frank, and C. S. Sadof. 2015. Do leaf domatia mediate intraguild predation and host plant resistance to Oligonychus aceris (Shimer) on Red Sunset Maple (Acer rubrum)? Biological Control 90:187-192.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Prado, J., M. Mickelbart, C. Quesada, and C.S. Sadof. 2015. Effects of Fertilization on Potato Leafhopper and Maple Spider Mite on Nursery Grown Maple. Journal of Economic Entomology. 108:1221-1227.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Hughes, G. Sadof, C.S. and M. D. Ginzel 2015. A Borer-specific Assessment Scheme for Identifying Sentinel Trees to Delimit Invasive Borers in Urban Forests. Arboriculture and Urban Forestry.41: 125-135.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Eschen, R.1, Britton, K.2, Brockerhoff, E.3, Burgess, T.4, Dalley, V.5, Epanchin-Niell, R.S.6, Gupta, K.7, Hardy, G.4, de Hoop, M.B.8, Huang, Y.9, Kenis, M.1, Kimani, E.10, Li, H.-M.11, Liebhold, A.M.12, Olsen, S.5, Ormrod, R.13, Otieno, W.14, Sadof, C.15, Tadeu, E.16, Theyse, M. 2015 International differences in national phytosanitary legislations and regulations, despite common basis. Environmental Science and Policy. 51:228-237


Progress 10/01/13 to 09/30/14

Outputs
Target Audience: My audience included urban forester, landscape producers, the nursery industry and home horticulure. Our research on maple spider mites outbreaks have indicated that the presence of leaf domatia on red maples reduce intraguild predation and the potential for spider mite outbreaks. A paper was published on this research in the Journal of Economic Entomology. Two papers were published on my student’s work in reducing invasive species movement on Dracaena from Costa Rica. I was invited to be a part of a SESYNC work group to examine movement of insects on nursery stock. We conducted insecticide trials and areawide management programs to determine effectiveness of insecticides against emerald ash borer. The EAB cost calculator was modified to include an invasion wave model that predicts tree mortality. We now have 4 apps developed to support decision making on ornamental plants and trees (Purdueplantdoctor.com). We have sold over 6000 copies since the inception of the Purdue Tree Doctor App in 2012. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? I have been disseminating information at regional meetings and conferences. How have the results been disseminated to communities of interest? Identify tactics for reducing pest problems in production and landscape systems that improve plant quality while minimizing pesticide inputs. Based on our maple research, we have advised nursery producers to avoid using early season pesticides on varieties of maple that are subject to spider mite problem. The new emerald ash borer cost calculator has been used in cities from North Carolina to Colorado to justify the use of insecticides to save trees. Develop systems for reducing pest abundance in domestic and offshore ornamental productions systems. None Develop tools for early detection and rapid response to exotic invasive pests of urban forests. We conducted insecticide trials and areawide management programs to determine effectiveness of insecticides against emerald ash borer. . We now have 4 apps developed to support decision making on ornamental plants and trees (Purdueplantdoctor.com). We have sold over 6000 copies since the inception of the Purdue Tree Doctor App in 2012. What do you plan to do during the next reporting period to accomplish the goals? Identify tactics for reducing pest problems in production and landscape systems that improve plant quality while minimizing pesticide inputs. I am conducting resaerch on scale insects attacking honeylocust and pine trees in the landscape. Develop systems for reducing pest abundance in domestic and offshore ornamental productions systems. I will be working with the Maryland SESYNC group on reducing invasive pest movement on live plants grown for planting. Develop tools for early detection and rapid response to exotic invasive pests of urban forests. I will continueto keep my apps updated andhave plans to develop a turf app. My EAB cost calculator will also be maintained.

Impacts
What was accomplished under these goals? Identify tactics for reducing pest problems in production and landscape systems that improve plant quality while minimizing pesticide inputs. Outputs. Our research on maple spider mites outbreaks have indicated that the presence of leaf domatia on red maples reduce intraguild predation and the potential for spider mite outbreaks. A paper was published on this research in the Journal of Economic Entomology Develop systems for reducing pest abundance in domestic and offshore ornamental productions systems. Two papers were published on my student's work in reducing invasive species movement on Dracaena from Costa Rica. I was invited to be a part of a SESYNC work group to examine movement of insects on nursery stock. 3. Develop tools for early detection and rapid response to exotic invasive pests of urban forests. We conducted insecticide trials and areawide management programs to determine effectiveness of insecticides against emerald ash borer. The EAB cost calculator was modified to include an invasion wave model that predicts tree mortality. We now have 4 apps developed to support decision making on ornamental plants and trees (Purdueplantdoctor.com). We have sold over 6000 copies since the inception of the Purdue Tree Doctor App in 2012.

Publications

  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Prado, J, C. Quesada, and C. Sadof. 2014 Effects of pesticide application on arthropod pests of nursery grown maple. Journal of economic entomology 107 (2), 708-717
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Sadof, M. Linkimer, E. Hidalgo, F. Casanoves, K. Gibson, and T.J. Benjamin 2014 Effects of weed cover composition on insect pest and natural enemy abundance in a field of Dracaena marginata (Asparagales: Asparagacae) in Costa Rica. Environmental Entomology 43: 320-327.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Nagle, A.M., R. Usborne, A. Stone, D.McCullough and C. S. Sadof 2014. Power hours-invasive species communication through collaborative webinars. Journal of Extension April 2014. Vol. 52. No 2.http://www.joe.org/joe/2014april/iw1.php of Extension 52.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Beckerman, J.L., and C. S. Sadof 2013. Caught with your plants down? Theres an app for that! Journal of Extension. April 2013 Vol. 51. No. 2. 2TOT3. http://www.joe.org/joe/2013april/tt3.php
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Hidalgo, E., T. J. Benjamin, F. Casanoves, and C. S. Sadof 2013. Factors influencing the abundance of pests in production fields and rates of interception of Dracaena marginata imported from Costa Rica. J. Econ. Entomol. 106:2027-2034.


Progress 10/01/12 to 09/30/13

Outputs
OUTPUTS: Our research on maple spider mites outbreaks have indicated that the presence of leaf domatia on red maples reduce intraguild predation and the potential for spider mite outbreaks. Research on calico scales on honeylocust in downtown Indianapolis suggest that bifenthrin provides good control, but has an increased potential for spider mite outbreaks. The emerald ash borer cost calculator has been revised to incorporate an invasion wave model for predicting tree mortality in the absence of insecticide treatment. This also provides the capacity to stage infestation to more realistically quantify costs and benefits of various management schemes to control the emerald ash borer. My two PhD students working on pests of Dracaena received their PhD in spring of 2012. These students are studying the relationships between pest management practices of Dracaena, the abundance of weed and insect pests in the field and the rates of interception. We evaluated field plots in Indianapolis and Lafayette to determine the relationship between the presence of borer holes in sites at the crest and cusp of EAB infestations and tree. We are in the process of evaluating our third season of data. We also developed an I-phone app called the Purdue Tree Doctor that allows rapid identification of 175 plant disorders on 60 genera of trees. These results have been disseminated in trade journal articles, and meetings. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Our research targets municipalities, nursery producers in the US and Costa Rica. Our research changed export regulations for Dracaena. Our I-phone app is designed to target professional and homeowners who may have problems on trees. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
In June of 2012, rules for exporting Dracaena from Costa Rica were changed based on research conducted with my students and colleagues at CATIE in Costa Rica. The only producers allowed to export are those who use the best management practices we developed in our research program. These producers are allowed to ship Dracaena plants up to 54 inches based on the finding that the number of quarantined pests on large Dracaena was not significantly more than those on small plants. The new emerald ash borer cost calculator has been used in cities from Maryland to Minnesota to justify the use of insecticides to save trees.Based on our maple research, we have advised nursery producers to avoid using early season pesticides on varieties of maple that are subject to spider mite problem. This has resulted in substantial reduction in pesticide use on Autumn blaze maples grown in nurseries. Our honeylocust research has identified two new times to apply pesticides. As a result many landscapers are beginning to apply pesticides at these times to get better control. By October 1 over 100 copies of the Purdue Tree Doctor app was sold.

Publications

  • Frank, S.D. and Sadof, C.S. 2011 Reducing insecticide volume and non-target effects of ambrosia beetle management in nurseries. Journal of Economic Entomology. 104:1960-1968.
  • Blubaugh, C. K, V. A. Caceres, I. Kaplan, J. Larson, C. S. Sadof and D. S. Richmond 2011. Ground beetle (Coleoptera: Carbabidae) phenology, diversity, and response to weed cover in a turfgrass ecosystem. Environmental Entomology Vol: 40 1093-1101.


Progress 10/01/10 to 09/30/11

Outputs
OUTPUTS: We continued research on the abundance of maple spider mites found on Red Sunset red maple and Autumn blaze Freeman maple in Indiana nurseries. We determined that spider mite problems resulted from early season applications of insecticides against leafhoppers. A field trial was conducted to identify best management practices for managing calico scales on honeylocust in downtown Indianapolis. Impacts of these practices on calico scale and spider mite populations were evaluated. Results of these studies have been distributed during outreach sessions during trade shows. A cost calculator was developed to quantify costs and benefits of various management schemes to control the emerald ash borer. This calculator has been posted on the eabindiana.info website and has over 800 users to date. I travelled to Costa Rica to work with my two PhD students at CATIE . These students are studying the relationships between pest management practices of Dracaena, their abundance in the field and the rates of interception. To date their focus has been on weed control and how size impacts pest abundance. In particular we examined if there was a scientific basis for size restrictions on exported Dracaena. We found no relationship between plant size and pest abundance. We evaluated field plots in Indianapolis and Lafayette to determine the relationship between the presence of borer holes in sites at the crest and cusp of EAB infestations and tree. We are in the process of evaluating our second season of data. PARTICIPANTS: Students Julia Prado, Carlos Quesada, Adam Witte, Ashley Kissick Institutions CATIE, USDA APHIS, USDA FS, Indiana Department of Natural Resources TARGET AUDIENCES: Nursery industry, Urban foresters, homeowners, Master Gardeners, PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Based on our maple research, we have advised nursery producers to avoid using early season insecticides on varieties of maple that are subject to spider mite problem. This has resulted in substantial reduction in insecticides use on Autumn blaze maples grown in nurseries. Our honeylocust research has identified two new times to apply insecticides. As a result many landscapers are beginning to apply pesticides at these times to get better control. The emerald ash borer cost calculator has been used in cities from Maryland to Minnesota to improve decision making and management of ash trees. Our research has stimulated a proposed regulatory change for Costa Rican Dracaena. There is a proposal now to increase the maximum allowed plant size from 18" to 45". This could open up markets for Costa Rican farmers and provide consumers with higher quality plants at a lesser cost.

Publications

  • England, K. M., C. S. Sadof, L. A. Canas, C. H. Kuniyoshi, and R. G. Lopez 2011. Effects of selected fertilizers on the life history of Bemesia tabaci, biotype B. Journ. Econ. Entomol. 104:548-554.
  • Sadof, C. S., L. Purcell, F J. Bishop, C. Quesada, and, Zhang, Z. W. 2011. Evaluating restoration capacity and costs of managing the emerald ash borer with a web-based cost calculator in urban forests. Arboriculture and Urban Forestry 37:74-83.


Progress 10/01/09 to 09/30/10

Outputs
OUTPUTS: A cost calculator was posted on the web to help arborists project the costs of managing ash trees for emerald ash borer over the course of a 25 year period. Use of this calculator was presented in research and Extension seminars in 4 states. The calculator was also the topic of a 2 national webinars. An article on how the calculator can be used to explore the economic consequences of management choices has been submitted for publication. Two research articles were published in refereed journals to describe how bagworms, a key pest of urban landscapes disperse and how these dispersal choices affect survival. PARTICIPANTS: Matthew D. Ginzel, Forest Entomology, Dept. of Entomology Purdue Jeffrey D. Holland, Landscape Ecologist, Dept. of Entomology Purdue Lindsey Purcell, Department of Forestry and Natural Resources , Purdue Marc Rhainds, Agriculture Canada TARGET AUDIENCES: Seminars were given to members of the green industry in Kentucky, Indiana, Illinois, Wisconsin and Minneapolis as well as in a national webinar to promote the EAB Cost Calculator. Extension Collaborators Dan Herms, Ohio State Deborah McCullough, Michigan State Chris Williamson, Wisconsin Phil Nixon, Illinois John Lloyd, Rainbow Tree, Minneapolis MN Jodie Ellis, Purdue University PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Development of the emerald ash borer cost calculator has been used by over 800 arborists in 21 states. The tool has been used in Minneapolis, St Louis, Indianapolis, Milwaukee and Chicago to make important decisions on how to protect trees. Arborists have used them to manage over 850,000 Trees. Bagworm dispersal has been found to be largely limited to the host tree. Dispersal, however can extend large distance during wind. Few larvae survive. The patchy distribution of bagworms suggest that control practices should involve close inspection of trees for pest to identify hot spots that can be controlled with insecticides.

Publications

  • Rhainds, M., C. Sadof, and C. Quesada 2010. Dispersal and development of bagworm larvae on three host plants. Journ. Applied Entomol. 134:81-90.
  • Rhainds, M. and C. S. Sadof. 2009. Fitness consequence of pupation site for bagworms (Lepidoptera: Psychidae) on arborvitae. Applied Entomol. and Zool. 44: 323-329.


Progress 10/01/08 to 09/30/09

Outputs
OUTPUTS: EMERALD ASH BORER:. We developed a calculator for cities to estimate costs of control, replacement, and projected size of forests over a 25 year period. http://extension.entm.purdue.edu/treecomputer/index.php EVERGREEN BAGWORMS: We have published studies on three new insecticides for use against the evergreen bagworm. Two of these products, applied as foliar material, buprofizen and chlorantraniprole are reduced risk products with a low toxicity to natural enemies of spider mites. A third product, dinotefuran can be applied as a soil systemic. NURSERY BEST MANAGEMENT PRACTICES PROGRAMS. Ornamental nursery stock is a significant source of invasive pests. We worked with Dracaena marginata growers in Costa Rica to identify sources of pests that were intercepted on plants at the port in Miami. We developed a sampling system and systematically studied the impact various grower practices on the abundance of key pests. Research was coordinated out of CATIE in Turrialba, Costa Rica. Three masters students received their degrees in entomology during the research project, Julia Prado, Gerardo Perez and Adriana Villalobos. BORERS IN SOLID WOOD PACKING: In response to the introduction of exotic invasive wood borers we conducted surveys to identify a target audience for training how to look for exotic woodboring pests that could be located in warehouse. PARTICIPANTS: Partner organizations include: Indiana Department of Natural Resources, USDA APHIS, The Ohio State University, TARGET AUDIENCES: City foresters, nursery producers, landscape managers, regulatory agencies attended workshops and seminars about nursery best management practices, the emerald ash borer, and the biology of bagworms. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
EMERALD ASH BORER: Over 400 forest managers have registered to use this calculator from cities throughout the known North American range of the emerald ash borer/ BAGWORM: Three new insecticide treatments are now available for use in the nursery and landscape industry. The availability of a soil applied insecticide will help homeowners treat heavy infestations without the need for spray equipment and drift. NURSERY BEST MANAGEMENT PRACTICES PROGRAMS.:. Identification of practices responsible for increased pest abundance resulted in creation of workshops for growers. Growers participating in a cleanstock program reduced their interceptions to near zero. BORERS IN SOLID WOOD PACKING:. A survey of pest control operators indicated that while most individuals wanted to respond appropriately to the detection of an invasive species few knew the appropriate action to take in response to the detection of an insect. This stimulated us to develop a course to teach pest control operators how to respond in a manner that notifies authorities and prevents the spread of solid wood borers to the native forest.

Publications

  • Rhainds, M. Leather, S. R., and C. S. Sadof. 2008. Polyphagy, flightlessness and reproductive output of females: a case study with bagworms (Lepidoptera: Psychidae. Ecological Entomology. 33:663-672.
  • Prado, J. C., F. Casanoves, E. Hildago, T. Benjamin, and C. S. Sadof. 2008. Effects of production practices on the abundance of quarantine pests in Dracaena marginata in Costa Rican production fields. Journ. Econ. Entomol. 101: 1779-1785.
  • 3Walter , Ashley D., Ellis, J. A. and C. S. Sadof. 2009. Developing a program to increase early detection and reporting of exotic woodboring pests. American Entomologist. 55:26-28.
  • Rhainds, M. and C. S. Sadof. 2009. Control of bagworms (Lepidoptera: Psychidae) using contact and soil applied systemic insecticides. Journ. Econ. Entomology. 102:1164-1169.
  • Rhainds, M. and C. S. Sadof. 2009. Fitness consequence of pupation site for bagworms (Lepidoptera: Psychidae) on arborvitae. Applied Entomol. and Zool. 44: 323-329.


Progress 10/01/07 to 09/30/08

Outputs
OUTPUTS: DRACAENA CLEANSTOCK PROGRAM. Ornamental nursery stock is a significant source of invasive pests. We worked with Dracaena marginata growers in Costa Rica to identify sources of pests that were intercepted on plants at the port in Miami. We developed a sampling system and systematically studied the impact various grower practices on the abundance of key pests. Research was coordinated out of CATIE in Turrialba, Costa Rica. Three masters students received their degrees in entomology during the research project, Julia Prado, Gerardo Perez and Adriana Villalobos. BORERS IN SOLID WOOD PACKING: In response to the introduction of exotic invasive wood borers we conducted surveys to identify a target audience for training how to look for exotic woodboring pests that could be located in warehouse. EMERALD ASH BORER:. We developed a preparedness plan for Emerald ash borer in Indiana to help municipalities plan for the arrival of this pest in their cities. http://www.entm.purdue.edu/EAB/management/for_city_town.shtml EVERGREEN BAGWORMS:. To better understand the movement of bagworms we studied their population dynamics on white pine., Pinus strobus (L). at 12 sites within a 50-km radius in central Indiana. The number of live bagworms declined over time by up to 95% in some sites, and the rate of population decline increased with the initial density of larvae. A comparison of population density of bagworms in past generations with that of the current-year generation revealed that sites heavily infested with bagworms from previous years carried a high number of live larvae early but not late in the season. The positive relationship between densities of bagworms in past and current generations observed at five of 122 sites suggests that larvae commonly do not disperse, when they emerge on a suitable host. However. there was considerable variation relative to this pattern, suggesting that dispersal is common as well. Pupation and emergence of adults occurred in late summer and early fall, with some level of phenological asynchrony observed at different sites. Dates corresponding to 50% pupation or adult emergence varied by upto 12 d at different sites. Males suffered higher mortality than females during the pupal stage. The positive correlation between the mortality level of female pupae and previous years population density may be related to a buildup of populations of natural enemies in sites that were previously heavily infested with bagworms. PARTICIPANTS: Three students obtained MS Degrees at CATIE in Turrialba Costa Rica. One of these students, Julia Prado is studying at Purdue to get her PhD Partner organizations include the Minstry of Agriculture of Costa Rica, Corporacion Nacional de Production de Costa Rica, USDA APHIS, Indiana DNR. TARGET AUDIENCES: The target of my research efforts include the domestic green industry, landscaper managers, nursery and greenhouse production and home owners. Internationally I am working with growers in other countries developing an export market to the US. PROJECT MODIFICATIONS: The arrival of emerald ash borer into Indiana has caused me to shift my focus to emphasize invasive species. For these reason a substantial part of my work involves managing invasives like EAB that are already in Indiana, and working with nursery exporters to prevent the importation of invasive species. In the process I am continuing to take the basic ecological approach that was part of my orignial proposal. The major difference is the scale at which this is applied.

Impacts
DRACAENA CLEANSTOCK PROGRAM:. Identification of practices responsible for increased pest abundance resulted in creation of workshops for growers. Growers participating in a cleanstock program reduced their interceptions to near zero. BORERS IN SOLID WOOD PACKING:. A survey of pest control operators indicated that while most individuals wanted to respond appropriately to the detection of an invasive species few knew the appropriate action to take in response to the detection of an insect. This stimulated us to develop a course to teach pest control operators how to respond in a manner that notifies authorities and prevents the spread of solid wood borers to the native forest. EMERALD ASH BORER: Cities in Indiana now have a system in place for planning for the arrival of the emerald ash borer in their communities. BAGWORM: We have demonstrated that the limited ability of bagworms to disperse indicates that bagworm population growth is largely determined by the local population of bagworms in previous years. As such, control of bagworms should be implemented on a local scale.

Publications

  • Walters A.D., and C. S. Sadof 2008. Safe and Sound: Purdue researchers help PCOs implement safer inspection practices to detect invasive species. Pest Control Technology, March, 130-132.
  • Sadof, C. S. , Benjamin T. Hidalgo, E. 2008. Lock Stock and Barrel, The Dracaena cleanstock program brings new opportunities for Florida and Costa Rican growers. Ornamental Outlook March, 42-44
  • Rhainds M. Sadof C. 2008. Elements of population dynamics of bagworm (Lepidoptera : Psychidae) on hedge rows of white pine. [Article] Annals of the Entomological Society of America. 101(5):872-880


Progress 10/01/06 to 09/30/07

Outputs
OUTPUTS: In no-choice laboratory assays, foliar applications of azadirachtin caused low rates of morbidity to adult beetles and were unable to deter feeding. In contrast, both foliar applied carbaryl and soil applied imidacloprid caused high rates of morbidity and reduced feeding injury. In the field, foliar sprays of azadirachtin and carbaryl, deterred feeding on foliage under low beetle pressure (maximum of 25% defoliation in untreated controls), when applied once weekly after first beetle flight or every two weeks after a 5% injury threshold was reached. A single foliar application of these materials at the 5% injury level did not significantly reduce peak defoliation. Soil applications of imidacloprid also deterred foliar feeding in the field. Blooms were more difficult to protect with both foliar and soil applied insecticides with only weekly application of foliar insecticides providing significant reductions in bloom injury. Removing beetles and/or blooms provided only marginally greater reductions in leaf and flower injury. This suggests that blocking the feeding induced aggregation response of Japanese beetles can provide only modest levels of control in roses where both flowers and feeding-induced volatiles recruit beetles to plants. A second study evaluated azadirachtin and imidacloprid for their ability to reduce injury by Japanese beetles [Popillia japonica (Coleoptera: Scarabaeidae)], on floribunda type roses (Rosa sp. 'Acadia Sunrise'), either applied to foliage or as a soil drench. Roses were arranged in field plots and exposed to resident adult beetle populations. Insecticides were evaluated in field and laboratory trials PARTICIPANTS: Justin Vitullo carried out these experiements as part of his training to get a Masters in Entomology. The project was funded by a combination of funds from IR-4 and small grants from Bayer and PBI Gordon. Master Gardeners were also part of the research project. TARGET AUDIENCES: The project was designed to help provide advice for home gardeners and public gardens. Information has been presented to the Illinois Indiana Rose growers, and in Master Gardener meetings throughout the state of Indiana.

Impacts
Field studies of roses indicated that applications of foliar insecticide every other week was as effective as weekly applications. Although many studies have demonstrated that floral resource plants will attract natural enemies near pest infested plants few have been able to demonstrate their impact pest abundance. Our research demonstrates that floral resource plants have subtle, but significant effects on the abundance of scale insects. Indeed we found that the presence or absence of flowers only occasionally contributed to rates at which parasites attacked euonymus scales. The ability of these resource plants to elevate the rates of biological control was more related to the ability of these resource plants to add vegetative mass in the newly planted landscapes of euonymus ground cover. Initially, during the first 2 summers after establishing this landscape, the rates of parasitism were enhanced only in plantings of euonymus that were surrounded by flowers. As this ground cover and the floral resource plants matured over time, rates of parasitism increased throughout the entire landscape, and thereby lowering the entire population of scales. Thus planting floral resource plants can be a good way for consumers to jumpstart biological control in newly planted landscapes. In a second study laboratory assays of leaves collected from plants 14 d after soil applications of azadirachtin were less preferred by adult beetles than those collected from untreated controls. Plants in field trials that received soil treatments of either imidacloprid or azadirachtin had defoliation levels that were below 8% throughout the entire season, whereas untreated control plants were 20% defoliated. Addition of foliar sprays to soil applied insecticides provided no added protection to foliage. Rose blooms were more difficult to protect with both foliar and soil-applied insecticides. Bloom injury of untreated controls varied between 20% to 30%, while plants receiving soil applications of azadirachtin varied between 0.2% to 18%. Soil applications of imidacloprid provided somewhat better protection of blooms with injury ranging between 0.2% to 8%. Foliar applications of azadirachtin gave no added protection to blooms of plants treated with imidacloprid. Adding carbaryl foliar treatments every 2 weeks improved control to less than 2% injury, a level that was comparable to weekly application of carbaryl. Soil-applied azadirachtin has the potential to reduce the need for foliar applications of carbaryl in rose gardens.

Publications

  • Vitullo, J.M. Sadof, C.S. 2007. Effects of Pesticide Applications and Cultural Controls on Efficacy of Control for Adult Japanese Beetles (Coleoptera: Scarabaeidae) on Roses Journal of economic entomology. 100: 95-102.
  • Vitullo, J.M. Sadof, C.S. 2007. Efficacy of Soil and Foliar-applied Azadirachtin in Combination with and in Comparison to Soil-applied Imidacloprid and Foliar-applied Carbaryl Against Japanese Beetles on Roses. HortTechnology. 17:. 316-321.


Progress 10/01/05 to 09/30/06

Outputs
We tested the hypothesis that regulation of an herbivorous pest of ornamental plants would be improved by providing floral resources for adult natural enemies. The herbivore was euonymus scale, Unaspis euonymi (Comstock) (Homoptera: Diaspididae), a serious pest of woody ornamental plants. The experimental landscape consisted of 3 x 3 m plots, each containing a central bed of Euonymus fortunei (Turcz.) that was infested with the scale. Floral resource plants were cultivars of four species that overlapped in bloom periods to provide a continuous supply of floral resources during summer, including Trifolium repens L., Euphorbia epithymoides L., Coreopsis verticillata L. var. Moonbeam, and Solidago canadensis L. var. Golden Baby. Plots contained either low or high densities of all four species, or no resource plants. Densities of euonymus scale were typically lower in plots containing resource plants than in plots without them. Parasitism by Encarsia citrina (Craw.) (Hymenoptera: Aphelinidae) was rarely influenced by the experimental treatments, flower biomass, whole-plant biomass, or scale density, but in some cases was inversely correlated with density of scales within a generation and in the previous generation. Parasitism occasionally reduced densities of scales in plots containing resource plants, but this effect apparently was more related to vegetative qualities of plants than availability of floral resources. A steady increase in parasitism rate over the three-year course of the experiment at the spatial scale of the entire landscape was associated with decreasing density of scales, suggesting a numerical response by the parasitoid population. These findings suggest that the parasitoid is capable of effectively regulating euonymus scale in ornamental landscapes where environmental conditions are favorable.

Impacts
Although many studies have demonstrated that floral resource plants will attract natural enemies near pest infested plants few have been able to demonstrate their impact pest abundance. Our research demonstrates that floral resource plants have subtle, but significant effects on the abundance of scale insects. Indeed we found that the presence or absence of flowers only occasionally contributed to rates at which parasites attacked euonymus scales. The ability of these resource plants to elevate the rates of biological control was more related to the ability of these resource plants to add vegetative mass in the newly planted landscapes of euonymus ground cover. Initially, during the first 2 summers after establishing this landscape, the rates of parasitism were enhanced only in plantings of euonymus that were surrounded by flowers. As this ground cover and the floral resource plants matured over time, rates of parasitism increased throughout the entire landscape, and thereby lowering the entire population of scales. Thus planting floral resource plants is a good recommendation to clientelle wanting to jumpstart the capacity of conservation biological in newly planted landscapes.

Publications

  • Rebek, E. J., C. S. Sadof, and L. M. Hanks 2006. Influence of Floral Resource Plants on Regulation of an Armored Scale Pest by the Parasitoid Encarsia citrina (Craw.) (Hymenoptera: Aphelinidae) Biological Control 37:320-328


Progress 10/01/04 to 09/30/05

Outputs
We manipulated densities of flowering plants to test the hypothesis that ornamental landscapes with floral resource plants contain more natural enemies than landscapes without these plants. We established an experimental landscape consisting of 3 x 3 m plots that contained a central bed of Euonymus fortunei (Turcz.) and either low or high densities of four species of perennial flowering plants that were planted through wood mulch. Control plots included only mulch. The cultivars of perennials, Trifolium repens L., Euphorbia polychroma L., Coreopsis verticillata L. var. Moonbeam, and Solidago canadensis L. var. Golden Baby, were chosen because their staggered bloom periods would provide nectar and pollen for natural enemies throughout the summer months. We used yellow sticky cards and a vacuum sampler to collect arthropods from experimental plots in 2000-2003. Total natural enemies, and spiders and parasitic wasps, specifically, were typically most abundant in euonymus beds surrounded by flowering plants. The abundance of parasitic wasps and total natural enemies on sticky cards was positively correlated with biomass of Euphorbia polychroma within plots, and that of all flowering plants combined. Removal of inflorescences from plants in 2003 did not affect patterns of natural enemy abundance or dispersion of natural enemies within the landscape, suggesting that vegetative characteristics of plants, rather than flowers, influenced the abundance of natural enemies. We conclude that despite our inability to measure an effect of flowers per se, including floral resource plants in landscapes enhances the abundance of natural enemies. Populations of mimosa webworm, Homadaula anisocentra Meyrick, and its parasitoids, Elasmus albizziae (Burks) and Parania geniculata (Holmgren) were observed on thornless honeylocust, Gleditsia triacanthos var. inermis L., at the West Lafayette, IN campus of Purdue University between 1998 and 2001. Mimosa webworm populations were quantified by visually estimating percentage browning of each tree canopy. During the course of the study 71.5 percent of all parasitized mimosa webworm pupae were attacked by E. albizziae. The remaining parasitized pupae were attacked by P. geniculata. Total numbers of E. albizziae collected per tree in a season were positively correlated with the percentage of canopy turned brown by the second generation of webworms. Annual estimates of E. albizziae abundance was positively correlated with year to year declines in second generation webworm injury when average estimates per tree declined, but absent when average injury increased. The apparent numeric response of these parasitoids and their delayed negative density dependence suggest that these parasites can occasionally contribute to decline of mimosa webworms in an urban forest.

Impacts
Implementation of biological control in urban landscapes is hampered by lack of information on the effectiveness of natural enemies in the urban matrix. We have found that planting flowers can greatly increase local abundance of natural enemies by providing shelter, and food. We also document how populations of a beneficial wasp are able to track the population of mimosa webworms and reduce their abundance on street trees. Taken together, our findings provide clear evidence about how actions can be taken to conserve the beneficial insects that reduce the abundance of pests in the landscape. By demonstrating these effects we hope to convince landscape managers and homeowners about the utility of biological control as an alternative to pesticides.

Publications

  • Rebek, E. J., C. S. Sadof, and L. M. Hanks 2005. Manipulating the abundance of natural enemies with floral resource plants. Biological Control 33:203-216.
  • Sadof, C. S. and R. N. Snyder, 2005. Seasonal phenology of parasitoids of mimosa webworm on honeylocust. Environmental Entomology 34: 70-75.


Progress 10/01/03 to 09/29/04

Outputs
Home gardens are frequently treated with pesticides, and in many areas, per acre pesticide use in home gardens exceeds that of many agricultural commodities. We developed ACORN, An Alternative Control Outreach Research Network, to teach home gardeners about alternatives and how to conduct research on alternatives to pesticides in home gardeners. This web-based program laid the groundwork for research conducted by home gardeners and stimulated a significant proportion of them to replace pesticide use with biological control. Master Gardeners in Indiana and Illinois were taught alternatives to the use of insecticides in workshops that focused on biological control of insect pests in home gardens. Gardeners also learned to conduct experiments in their backyards and were encouraged to participate in a summer research program that tested specific control methods. Workshop participants were surveyed before the workshop, and in two successive growing seasons to measure changes in their pest management practices. Home gardeners participated in research on one of 5 alterntatives to pesticides. Over five hundred Master Gardeners in Indiana and Illinois were taught alternatives to the use of insecticides in workshops that focused on biological control of insect pests in home gardens between 1998 and 2002. A total of 282 research plots were established in home gardens over this period. Overall, a significant percentage of gardeners stopped applying insecticides for up to two consecutive growing seasons after attending workshops. In addition, the adoption of biological control by participants appeared to be linked to their insecticide use and willingness to participate in the research process. A significant increase in the adoption of biological control was noted among garden researchers who did not use insecticides before the workshop or had reduced insecticide use following the workshop. No such change was noted for gardeners that did not conduct research. Home gardeners testing how straw mulch impacted natural enemy communities were able to demonstrate significant changes in the abundance of predaceous ground beetles in the two state area.

Impacts
Extension educators in 20 states, from New Jersey to Georgia and Alaska, have downloaded training materials from the Web site. Follow-up surveys showed that more than 20 percent of participants stopped applying insecticides, herbicides, and fungicides for up to two consecutive growing seasons. The Web site was also featured in HGTV.COM as a useful resource for finding alternatives to managing garden pests. Gardeners who voluntarily participated in biological control research more often adopted biological control practices. More than 30 percent of this group reduced or eliminated pesticide use in their gardens. Further, research we conducted on alternatives demonstrated how gardeners can enrich communities of natural enemies that control pests, through simple garden practices like mulching or by purchasing and releasing natural enemies.

Publications

  • C. S. Sadof, R. J. O Neil, Heraux, F., and R. N. Wiedenmann 2004. Reducing Insecticide Use in Home Gardens: Effects of Training and Volunteer Research on Adoption of Biological Control. Hort Tech. 14:149-154.
  • Wiedenmann R.N, C. S. Sadof, and R. J. O Neil 2004. Ground Beetle (Coleoptera: Carabidae) Assemblages in Mulched and Non-Mulched Garden Plots. J. Kansas Ent. Soc. 77:99-109


Progress 10/01/02 to 09/30/03

Outputs
Both defensive and nutritional hypotheses have been used to explain the improved performance of sucking insects on variegated plants. With portions of leaves unable to photosynthesize, variegated plants are likely to have less carbon assimilate to allocate to the production of defensive compounds than green plants. Alternatively, like plants grown in the shade, variegated plants compensate for reduced photosynthesis by allocating more of their biomass to the production of leaf area. As such, the improved response of sucking insects may be to due greater mobility of amino acid nitrogen and carbohydrates in the phloem to fuel the production of more leaves. We examined the amino acid and sucrose content of stem phloem excised from red-variegated, yellow-variegated and green-leafed coleus, plants and their relation to the life history characteristics of citrus mealybug, to test these defensive and nutritional hypotheses. Our data reject the nutritional hypothesis. Green-leafed plants had more than twice the concentrations of amino acids and sucrose in their phloem than did the variegated cultivars. Analysis of amino acid composition indicates that green-leafed plants had greater levels of shikimic acid precursors than did the variegated plants. Furthermore, life history characteristics of citrus mealybugs were adversely affected by increasing amounts of shikimic acid precursors. In conclusion, we find that the improved suitability of variegated plants is more consistent with carbon-based theories of plant defense. A two-year greenhouse study was conducted to evaluate the seasonal population dynamics and use of an action threshold for western flower thrips, Frankliniella occidentalis (Pergande) in cut carnation, Dianthus caryophyllus L. An action threshold of 20 thrips/card/week was adopted to time insecticide applications. The highest numbers of thrips were caught on blue-colored sticky cards from June through September whereas the lowest thrips numbers were present from November through March of 1994 and 1995. Thrips abundance on blue sticky cards was significantly correlated with both numbers of thrips in flowers and a subjective ranking of flower quality. This study suggests that sticky cards can be an effective tool for reducing insecticide applications in regions where there are seasonal fluctuations of thrips abundance. We tested several biorational and traditional insecticides for their ability to control euonymus scale, Unaspis euonymi (Comstock), and their potential impacts on the aphelinid parasitoid, Encarsia citrina (Crawford). Soil-applied acephate and foliar-applied pyriproxyfen exhibited superior control of euonymus scale, but also reduced numbers of surviving E. citrina. Imidacloprid failed to control euonymus scale and decreased parasitism by E. citrina.

Impacts
Plants with multicolored leaves (variegated plants) have been found to grow more slowly and be less well defended against pests than their green leaved counterparts. Planting variegated plants is likely to require more intensive pest management. Greenhouse studies indicate that sticky card traps can be used to track thrips damage and reduce the need for growers to spray insecticides. Studies suggest that certain pest problems like armored scale insect can be made worse when an insecticide is applied that kills more beneficial insects than pests.

Publications

  • Rebek, E. J. and C. S. Sadof 2003. Effects of Pesticide Applications on the Euonymus Scale (Homoptera: Diaspididae) and Its Parasitoid, Encarsia citrina (Hymenoptera: Aphelinidae). J. Econ. Entomol. 96:446-452.
  • Sadof, C. S., J. Neal, and R. A. Cloyd. 2003. Effect of variegation on phloem composition of Solenostemon scutellarioides (L.) and life history characteristics of Planococcus citri (Risso).J. Environ. Entomol. 32:463-469.
  • Cloyd, R. A., and C. S. Sadof 2003, Seasonal abundance and the use of an action threshold for western flower thrips, Frankliniella occidentalis (Pergande), in a cut carnation, Dianthus caryophyllus L. greenhouse. HortTechnology 13:497-500.


Progress 10/01/01 to 09/30/02

Outputs
The green industry and homeowners lack effective controls for armored scales insects. Plants like wintercreeper euonymus are not planted on many landscapes. Outbreaks often occur in urban areas that lack the resources which support the beneficial insects that keep them from becoming problems in landscapes. Control of these scales requires control tactics that can both reduce scale populations and conserve the beneficial insects responsible for long term control. We worked with euonymus scale Unaspis euounymi and its parasitoid Encarsia citrina to identify pesticides that could reduce pest populations without adversely affecting natural enemies. We identified horticultural oil, and an insect growth regulator (pyriproxifen) as the most effective and least likely to cause outbreaks of other pests. Both of these pesticides are on EPA's list of reduced risk pesticides because of their safety to the environment and low toxicity. Like most of the other pesticides in the study we found these materials to reduce the numbers of parasites in direct proportion to their ability to kill scales. This insecticide treatment, a soil drench of imidacloprid, depressed the populations of parasitoids below that which would be expected from simple scale mortality. As such,we were able to explain why applications of this material in the landscape resulted in increased populations of this pest in our previous studies.

Impacts
Homeowners can now use oil to control scale insects without adverse impact on non-target species. Landscapers have an effective bio-based pesticide (pyriproxifen) that is effective in heavy infestations. Outbreaks of armored scales can be lessened by urging homeowners to avoid the use of imidacloprid in their euonymus beds.

Publications

  • Sadof, C. S. and C. S. Sclar 2002. Developing an aesthetic threshold for a public display garden. J. Econ. Entomol. 95:2:348-353.
  • Sadof, C.S 2002. Scale inects on shade trees and shrubs. Purdue Cooperative Extension Service Bulletin E-29. 6 pp.


Progress 10/01/00 to 09/30/01

Outputs
Initially, the ornamental honeylocust trees were thought to be trouble-free; however, widespread plantings and overuse soon gave rise to 3 serious pest problems, honeylocust plant bug, Diaphnocoris chlorionis (Say), honeylocust spider mite (Platytetranychus multidigitalis) and mimosa webworm, Homadaula anisocentra. We examined the relationship of insect pest abundance to 3 landscape characteristics, host plant density, species diversity, and proportion of paved area around each honeylocust tree. One hundred trees, each with a minimum trunk diameter of 25 cm and located on the Purdue West Lafayette Campus, were surveyed each week for incidence of pests. Landscape characteristics for each tree were calculated using ArcView. Although each landscape factor was related to pest abundance, the nature of that relationship varied among pests and spatial scales. These findings illustrate the utility of GIS and the importance of spatial scale in studying the landscape ecology of urban pests. Impacts of cover sprays of residual insecticides on arthropod pests and their natural enemies were studied on trees and shrubs in urban settings. Trees in residential landscapes that received three covers sprays annually for many years harbored a greater diversity of scale insect pests and were much more likely to be infested with scales than trees in landscapes treated with cover sprays for shorter periods of time. Oak trees in an institutional landscape treated with residual insecticides harbored significantly lower numbers of beneficial arthropods than trees treated with a pesticide that lacked residual activity. The suppressive effect of the residual insecticides on natural enemies was pronounced on the community of parasitic wasps that attack a common scale insect pest of oaks, the obscure scale. The effect of residual insecticides on individual wasp species persisted four weeks after the pesticides were applied. Movement of felled pines during the winter months from infested areas to sawmills in uninfested areas, however, may pose a serious risk of moving the quarantined pest, Tomicus piniperda. Mark-release-recapture experiments were performed with logs coated with fluorescent powder and containing overwintering T. piniperda adults that marked themselves as they emerged in spring. Overall, 481 T. piniperda galleries were found on the experimental logs recovered from the four simulated millyards combined, of which 88.6% were found on logs in the central log piles in which the beetles had been overwintering. Tomicus piniperda adults dispersed and attacked logs at distances up to 100 m from a release point in the simulated millyards, and were captured in a-pinene-baited multiple funnel traps at distances up to 230 m in simulated millyards, 400 m around operational sawmills, and 800 m in the field trapping study. Although the numbers of T. piniperda captured were low, in all cases some beetles dispersed outside of millyards, despite the presence of abundant suitable breeding material. Therefore, logs containing overwintering T. piniperda adults pose a risk of spreading T. piniperda if not processed prior to initiation of spring flight.

Impacts
Arborists managing pests of honeylocust trees need to consider qualities of the landscape around each tree that can contribute to outbreaks of pest problems. By reducing the use of cover sprays and residual insecticides, arborists may be able to conserve communities of natural enemies in managed landscapes. The capacity of the pine shoot beetle to fly away from millyards justifies the continuation of the quarantine against this pest in the United States.

Publications

  • Sperry, C. E., W. R Chaney, G. Shao, and C. S. Sadof 2001. Effects of tree density, tree diversity, and percentage of hardscape on three insect pests of honeylocust. Journ. Arboriculture 27:263-271.
  • Raupp, M. J. J. J. Holmes, C. Sadof, P. Shrewsbury, and J. A. Davidson 2001. Effects of cover sprays and residual pesticides on scale insects and natural enemies in urban forests. Journ. Arboriculture 27: 203-213.
  • Poland, T. M, R. A. Haack, T. R. Petrice, C. S. Sadof, and D.W. Onstad. 2000. Dispersal of pine shoot beetle, Tomicus piniperda, from operational and simulated millyards. Canadian Entomol. 132:853-866.


Progress 10/01/99 to 09/30/00

Outputs
Studies in pachysandra groundcovers revealed that a soil drench of Merit (imidacloprid) was not able to control euonymus scale when compared with plots sprayed with water. Horticultural oil gave the greatest level of control (99 %) when applied in the dormant season followed by an application that targeted mobile stages of the insects during summer. Summer applications of acephate gave commercially acceptable control (66%). Most of the live and parasitized scales were observed in the middle and basal portions of the groundcover canopy. Rates of parasitized scales never exceeded 25% in the control plots. Rates of parasitism were too low to distinguish differences among rates of parasitism in the four treatments. By transplanting scale-infested plants into a simple landscape, we have been studying a native scale species with a rich natural enemy guild and an introduced scale species with relatively few natural enemies. The native scale species, Pine needle scale, Chionaspis pinifoliae (Fitch), is being studied in Champaign-Urbana, Illinois on Scotch pine, Pinus sylvestris L. The introduced scale species Euonymus scale (ES), Unaspis euonymi (Comstock),is being studied in nearby (ca 160 km) West Lafayette, Indiana on a low-growing cultivar of euonymus (Euonymus fortunei Turcz.). Both of these insects are economically important pests of woody plants, and both plant species are commonly planted in landscapes. Experimental plots have been planted with a blend of four perennial flowering plant species that were selected, based on flower morphology and nectar and pollen production, to produce a steady supply of food for natural enemies. Preliminary results indicate that flower plantings are able to attract natural enemies to plots. Effects of flowers on scale populations and parasitism have yet to be determined. One hundred honeylocust trees on the Purdue West Lafayette campus have been sampled twice each month from May through September to collect data on pests in a uniform manner. After three years of monitoring we are beginning to see increased pest abundance when trees are surrounded by pavement and buildings. We are currently conducting studies to determine whether the underlying mechanism is caused by the impact of the paved area on plant, and insect physiology, the natural enemies of insect pests, or all three factors. We expect our findings will be helpful in developing guidelines for landscape designers seeking to minimize pest problems. Ornamental plants are grown for their appearance. As such, one way to reduce reliance on pesticides is to increase public tolerance to insect injury. Surveys we conducted at Longwood Gardens indicate that people more tolerant of defoliation when they are distracted by showy flowers in an informal setting. In addition, people tend to be less discriminating when the best available plant has some pest injury. By far people were most discriminating when they were considering buying a plants. Thus any possibility of increase consumer tolerance to pest injury will be limited to landscapes, and not commercial sales situations.

Impacts
Horticultural oil has been identified as an effective way to control armored scales in groundcover plantings of euonymus. This reduced risk pesticide was more effective than application of the organophosphate insecticide Acephate, the industry standard for control.

Publications

  • Sadof, C. S. and D. C. Sclar. 2000. Effects of horticultural oil and foliar or soil applied systemic insecticides on euonymus scale in Pachysandra. J. Arboric. 26: 120-125.
  • Cloyd, R. A. and C. S. Sadof. 2000. Effects of plant architecture on the attack rate of Leptomastix dactylopii (Howard) (Hymenoptera: Pseudococcidae), a parasitoid of citrus mealybug, Planococcus citri (Risso) (Homoptera: Pseuodococcidae) Environ. Entomol. 29: 535-541.
  • Cloyd, R.A. and C. S. Sadof. 2000. Effects of a biorational insecticide on western flower thrips, Frankliniella occidentalis (Pergande), and comparison of natural enemy abundance inside and outside a greenhouse. HortTechnology 10: 359-362.


Progress 10/01/98 to 09/30/99

Outputs
Studies conducted with euonymus scale, Unaspis euonymi indicate that most armored scales are found deep within the canopy of the ground cover. Despite this canopy cover, the scale can still be effectively controlled with a high pressure spray oil in the dormant and the dormant season. The combination of dormant and foliar applications of horticultural oil gave better control of euonymus scale (99.5% reduction) than conventional materials (66% reduction with acephate). Systemic applications of imidacloprid were not effective ( a 45% increase). The effects of spinosad, on Western flower thrips, Frankliniella occidentalis, and its natural enemies were studied inside and outside of a greenhouse. Results indicated that spinosad conveyed effective thrips control in both conditions. More importantly, however, was that simply placing plants outside provided a significant measure of thrips control due to the actions of rainfall and natural enemies. Studies of Leptomastix dactylopii, a primary parasitoid of citrus mealybug, indicate that when given the same numbers of mealybugs on a plant, attack rates were proportional to most measures of plant size. This suggests that release rates against citrus mealybugs in greenhouses need to compensate for size of the plants being managed. Any convenient measure of plant size is equally effective for adjusting release rates.

Impacts
Landscape managers are likely to reduce their use of conventional pesticides because they can get better control of euonymus scale with horticultural oil than conventional materials. Similarly they can reduce pesticide use against western flower thrips by simply planting the plants out doors and letting the rainfall and natural enemies reduce populations. Greenhouse growers using biological control need to release more natural enemies as plant size increases.

Publications

  • Sadof, C. S. and C. S. Sclar 2000. Effects of horticultural oil and foliar or soil applied systemic insecticides on euonymus scale in Pachysandra. J. Arboriculture


Progress 10/01/97 to 09/30/98

Outputs
Research on tomicus piniperda culminated in the development of a compliance program for Christmas tree growers that is likely to reduce the risk of shipping infested trees out of the quarantined area. The compliance program reduces most of the pest population through strict applications of cultural controls such as sanitation and the use of trap logs. Work with western flower thrips has identified acephate as a potentially useful granular systemic insecticide. Research conducted on the citrus mealybug indicate that it is not likely to be controlled by parasitoid Leptomastix dactylopii on variegated plants when released at low rates.

Impacts
(N/A)

Publications

  • McCullough, D. G, and C. S. Sadof 1998. Evaluation of an Integrated Management and Compliance Program for Tomicus piniperda (Coleoptera: Csolytidiae) in Pine Christmas tree fields. J. Econ. Entomol 91:785-795.
  • Cloyd, R. A, and C. S. Sadof 1998. Flower quality, flower number, and wester flowerthrips density on Transvaal Daisy treated with granular insecticides. HortTechnology 8:567-570.
  • Cloyd, R.A., M. Brownbridge, and C. S. Sadof 1998. Greenhouse biological control of Western Flower Thrips. IPM Practitioner 20(8):1-9.
  • Yang, J., and C. Sadof 1997. Variation in the life history of the citrus mealybug parasitoid, Leptomastix dactylopii (Hymentoptera: Encrytidae) on three varieties of Coleus blumei. Environ. Entomol. 26:978-982.


Progress 10/01/96 to 09/30/97

Outputs
In Indiana growers will typically lose 25-50% of their crop to Zimmerman pine moth. This boring insect girdles the main stem of the tree, killing branches and limbs. After an 8 year study of Scotch pine Christmas tree varieties in a choose and cut plantation, we identified two varieties resistant to this pest. Resistant varieties tended to be of French and Belgian origin. Analysis of monoterpene content of twigs collected from the most resistant and most susceptible varieties failed to reveal a consistent pattern. By allowing trees to be sold in a choose and cut plantation, we were able to determine the relationship between the presence of wounds and consumer purchase. As expected, varieties with high rates of wounding had lower rates of sale. However, since a many of the trees sold were wounded, we questioned the idea of need having a zero tolerance for this pest in Christmas trees that are typically harvested 7-8 years after planting.

Impacts
(N/A)

Publications

  • Sadof, C. S. 1996. Resistance of Scotch pine varieties to Zimmerman pine moth (Lepidoptera: Pyralidae) and its impact on sales in a choose and cut Christmas tree plantation. Great Lakes Entomologist. 29:183-190
  • Sadof, C. S. and G. G. Grant 1997. Monoterpene composition of Pinus sylvestris varieties resistant and susceptible to Dioryctria zimmermani Grote (Lepidoptera: Pyralidae) J. Chemical Ecology. 23:1917-1927.
  • Haack R. A., R. K. Lawrence, D. G. McCullough, and C. S. Sadof . 1997. Tomicus piniperda in North America: An integrated response to a new exotic scolytid. pp 62-72. in J.C. Gregoire, A.M. Liebhold, F.M. Stephen, K.R. Day, and S.M. Salom (eds.) 1997. Proceedings: Integrating cultural tactics into the management of bark beetle and reforestation pests. USDA Forest Service General Technical Report NE-236 .


Progress 10/01/95 to 09/30/96

Outputs
After a two year pilot study in 18 fields in Indiana and Michigan we have developed procedures for Christmas tree growers that greatly reduce the population of pine shoot beetles in Scotch pine plantations. This protocol relies primarily on the cultural control of this pest through timely destruction of breeding material from the field. These procedures form the core of a USDA APHIS program that provides an alternative to crop inspection to reduce the risk of spreading this regulatory pest. Grower management records will be inspected to deterimine if they complied with the procedures we developed. This should facilitate timely shipment of the Christmas tree crop while reducing both the risk of shipping pine shoot beetle and the labor involved by inspection personel. The program will begin in January 1997.

Impacts
(N/A)

Publications

  • SADOF, C. S., WALTZ,R.D. and C. D. KELLAM. 1995. Differential shoot feeding by adult Tomicus piniperda L. (Coleoptera: Scolytidae) in mixed stands of native and introduced pine stands in Indiana. Great Lakes Entomol. 27:223-228.
  • YANG, J. and C. S. SADOF. 1995. Impact of red and yellow variegation in Coleus blumei on Planococcus citri (Homoptera: Psuedococcidae). Environ. Entomol. 20: 83-89.
  • SADOF, C.S. 1996. Maximizing Biological Control Opportunities, Arbor Age Magazine 16(4):pp28-32.


Progress 10/01/94 to 09/30/95

Outputs
Studies of leaf color variegation in Coleus plants indicated that this ornamentally valuable characteristic has significant impact on the life history of its principle pest, the citrus mealybug. Mealybugs on yellow-variegated and red-variegated Coleus, grew faster, produced more offspring and had a greater rate of successful colonization than when on green plants. When infested with similar numbers of citrus mealybugs, plants with variegated leaves died sooner than than green plants. This study suggests that a horticulturally important feature like leaf variegation can make a plant more vulnerable to pest injury.

Impacts
(N/A)

Publications

  • YANG, J. and SADOF, C. S. 1995. Variegation in Coleus blumei and the life history of citrus mealybug. (Homoptera: Pseudococcidae).


Progress 10/01/93 to 09/30/94

Outputs
Studies of pine shoot beetle in Christmas tree plantations indicate that infestations can potentially be reduced by using culled Christmas trees as baits. Placement of these trees out in the field during prior to the mating flight, attracts mating populations of beetles. Destruction of these trees prior to the emergence of their progeny was responsible for reducing the population of infested trees. A system of scouting, based on research conducted on consumer tolerance to insect injury on ornamentals, has been developed for landscapers. Implementation of this system in landscapes has reduced pesticide use by 50% on woody plants. Software has been developed for landscapers to help them rapidly summarize pest incidence and pesticide use in the landscape.

Impacts
(N/A)

Publications

  • SADOF, C. S., WALTZ, R. D. and KELLAM, C. D. 1994. Differential shoot feeding by adult Tomicus piniperda L. (Coleoptera: Scolytidae) in mixed stands of native and introduced pine stands in Indiana. Great Lakes Entomol. (in-press).
  • SADOF, C. S. and NAGARAJAN, K. 1994. Purdue Landscape IPM Software. Copyright Purdue Research Foundation. 94 pp.


Progress 10/01/92 to 09/30/93

Outputs
A survey of native pine species has shown that the newly introduced pine shoot beetle prefers native red pine trees over Scotch pine, its preferred host in Europe. Research also indicates that sanitation, or the removal of breeding material will be critical for control. We determined how variegation affects Leptomastix dactylopii, (Hymentoptera: Encyrtidae) a parasitoid of citrus mealybug on Coleus blumei. Studies indicate that red variegated plants and green plants produce mealybugs that are more suitable for L. dactylopii than yellow plants. Work is being conducted to determine the mechanism for this effect. We have also determined that the Korean Ladybeetle develop from an egg to an adult on oystershell scale. Work on life history parameters is being conducted to determine its potential use as an alternate host. Work conducted on consumer tolerance to pest injury suggest that the aesthetic standards of the landscape industry match those of their clientelle. Variability in clientelle response suggests the need for landscapers to discuss standards with their clientelle.

Impacts
(N/A)

Publications

  • SADOF, C.S. 1993. Keeping up Appearances. American Nurseryman 177(9):83-85.
  • SADOF, C.S., ALEXANDER, C. 1993. Determination of Aesthetic Injury Levels for T. urticae on Euonymus alatus compacta. J. Econ. Entomol. 86:1516-1521.
  • SADOF, C.S. and NEAL, J.J. 1993. Utilization of host plant resources by the Euonymus scale, Unaspis euonymi. Annals Entomol. Soc. Amer. 86:614-620.
  • EDDY, R.T. and SADOF, C.S. 1993. Training the mentally disabled as IPM Scouts. HortTechnology (in-press).
  • BULL, B.C., RAUPP, M.J. HARDIN, M.R. and SADOF, C.S. 1993. The suitability of five horticulturally important armored scale insects as hosts for an exotic predacious lady beetle. J. Environ. Hort. 11:28-30.


Progress 10/01/91 to 09/30/92

Outputs
We determined how feeding by Tetranychus urticae(Acari: Tetranychidae) affects the aesthetics and economic value of the deciduous shrub on Euonymus alatus. Less than 5% leaf discoloration reduced plant value in a retail nursery by 50%. A sampling plan was developed for predicting economic injury in the landscape. Work continues to determine the aesthetic preferences of different clientele groups. Preliminary work on variegated Coleus blumei and its principal pest the citrus mealybug, Plannococcus citri (Homoptera: Pseudococcidae) has been completed. Red and yellow variegated plants seem to be more susceptible to mealybug damage than green plants. This confirms the hypothesis generated from our previous work on Unaspis euonymi, that suggest variegated plants are more susceptible to plant injury than green plants. We continue to caution growers about the pest management consequences of choosing a variegated plant. Work is being conducted on the biological control of Unaspis euonymi by the Korean lady beetle Chilocorus kuwanae. Laboratory colonies have been established and field tests are underway to determine the host range of this scale natural enemy in Indiana.

Impacts
(N/A)

Publications

  • SADOF, C.S. AND RAUPP, M.J. 1992. Effect of leaf variegation in Euonymus japonica on Tetranychus urticae (Acari: Tetranychidae) Environ. Entomol. 21: 827-831.
  • WERREN, J.H., RAUPP, M.J., SADOF, C.S. AND ODELL, T.M. 1992. Host plants used by gypsy moth affect survival and development of the parasitoid Cotesia melanoscela. Environ. Entomol. 21:173-177.


Progress 10/01/90 to 09/30/91

Outputs
We elucidated the potential effects of variegated plants on patterns of herbivory and plant growth. Specifically we investigated Unaspis euonymi (Homoptera: Diaspididae) and Tetranychus urticae (Acari: Tetranychidae) on E. japonica var. aureus. Variegated cultivars of E. japonica had approximately 33% of their leaves lacking chlorophyll. This resulted in a 29% reduction in the plant relative growth rate. The fecundity of U. euonymi was higher on variegated plants than on green plants. The fecundity of T. urticae was unchanged on variegated plants. Furthermore, T. urticae preferred to feed on the green tissue of variegated leaves. Females laid the same number of eggs as did their cohorts on completely green leaves. This within-leaf pattern of feeding is opposite of preliminary findings with for Popillia japonica (Coleoptera: Scarabeiidae) feeding on Acer platanoides. However, P. japonica prefers to feed on variegated leaves. In summary we find additional support for the hypothesis that variegated plants pose potential maintenance problems in the landscape. They grow more slowly and are more susceptible to injury by common pests. We continue to caution landscapers and homeowners about this liability of variegated plants.

Impacts
(N/A)

Publications

  • SADOF, C.S. and M.J. RAUPP 1991. The impact of variegation in Euonymus japonica var. aureus on two phloem feeding insects. Environ. Entomol. 20:83-89.
  • SADOF, C.S. 1991. It's not easy being variegated. Amer. Nurseryman. 174(9):54-57.