Department of Entomology
288 Farm Lane Room 347
East Lansing, MI 48824
Area of Expertise:
Pest Management in Turfgrass and Nursery PlantsHome gardening questions? Call 1-888-678-3464 or Ask Extension
PhD - North Carolina State University (1985)
MS - University of Georgia (1980)
BS - Michigan State University (1978)
Dr. Smitley works closely with the turfgrass, nursery and floriculture industries on identifying insect pest problems, and researching best management practices to address them. Basic and applied research is followed with extension recommendations for growers. In 1991, Dr. Smitley worked with Dr. Bauer to introduce Entomophaga maimaiga, a natural fungal pathogen of gypsy moth, into Michigan. E. maimaiga is now widespread throughout the state and forest defoliation due to gypsy is less than 1/10th of what it was in the early 1990’s. From 2003 to 2010, cooperative research between the Smitley lab and industry led to the development of new management strategies for emerald ash borer, including a product that homeowners can purchase at the garden center, and the most widely used professional product for landscape trees: trunk injection with emamectin benzoate (TREEäge). Dr. Smitley introduced Ovavesicula popilliae, a natural pathogen of Japanese beetle, into Michigan in 1999 to help suppress populations of Japanese beetle. After 17 years, populations of Japanese beetle have declined in southern Michigan. In the last four years the Smitley lab has worked with the greenhouse and nursery industries to develop best management strategies for growing annuals, perennials, trees and shrubs that will be safe for pollinators. This led to organizing a national conference on ‘Protecting Pollinators in Urban and Rural Habitats’ and a regional extension bulletin: Protecting and Enhancing Pollinators in Urban Landscapes, MSU Extension Bulletin E3314, available at: bit.ly/IPMpollinators.
Current assignment: Teaching 15% | Research 35% | Extension 50%
ENT 364. Turfgrass Entomology is taught each fall semester to a class of 20 to 30 students, consisting mostly of Turf Management students in the 2-year or 4-year program. For six years I also taught a similar class at Sichuan Agricultural University in Ya’an, China, as part of the MSU Sino-American Turfgrass Management program. The turfgrass entomology class focuses on the identification and management of the most important turfgrass insect pests. There is one 2.5 hour lab and two lectures each week. Students have an exam every other week, make a collection of at least 70 species of insects, complete a laboratory practical, and a final exam. Objectives for the class are for all students to be able to sight identify the most important turfgrass pests and beneficials, be able to discuss practical management options, and to write a scouting and pest management plant, including a budget for the golf course, lawn care company, or sports complex where they work. An additional objective is to teach students about graduate school options, including how to apply to graduate schools and how to apply for teaching or research assistantships.
ISB 201. I teach Integrative Studies Biology: Insects, Global Sustainability and Science Literacy, each spring semester. Enrollment is 150 - 160. ISB 201 is an Environmental Science course. Major themes are (1) Scientific Literacy: how to interpret data and theories that appear in the news, (2) Global Sustainability: critical analysis of the costs and the benefits of human activities that impact natural systems, and (3) Insect Ecology: the interdependence of life on earth.
In 2014 my lab began work on developing best management strategies for nursery and greenhouse growers that allows them to produce high quality plants that will also be safe for pollinators. We are now evaluating the potential impact of systemic insecticides on pollinators by looking at residues in pollen and nectar at various time intervals after they are applied. We are also working with Dr. Cristi Palmer and a team of 8 entomologists around the country to evaluate how attractive the top 30 types of annuals and perennials sold in garden centers are to pollinators.
In 1999 and 2000 my lab collected a newly discovered microsporidean pathogen of Japanese beetle, Ovavesicula popilliae, from Connecticut and introduced it to 8 research sites in Michigan. In the following 17 years, O. popilliae has built-up to epizootic levels and spread rapidly to surrounding areas. During this time period populations of Japanese beetle have sharply declined as the infection rates of the pathogen increased. We are continuing our research on the long-term impact of O. popilliae on Japanese beetle. I am also working with Phil Lewis, USDA-APHIS on ‘Facilitating spread of the microsporidian pathogen, Ovavesicula popilliae, for long-term suppression of Japanese beetle’. This project will introduce O. popilliae to key locations in from the Midwest to the Rocky Mountains to facilitate the spread of the pathogen to leading-edge infestations of Japanese beetle in the United States.
A top priority has been to provide new information on how to protect pollinators to extension specialists and educators, nation-wide. At an Ornamentals Workshop in Kanuga, Steve Frank at NCSU and I began plans to organize the “First Protecting Pollinators in Ornamental Landscapes Conference”. It was held Oct. 12-14, 2015, in Hendersonville, North Carolina. 187 participants from 35 states and three countries attended the conference to see 22 speakers from 11 Universities. We just completed the second ‘Protecting Pollinators in Urban Landscapes’ conference, held October 9 – 11, 2017, in Traverse City Michigan): http://protectingpollinators.org. Following the first conference my lab published the regional Extension publication: ‘Protecting and Enhancing Pollinators in Urban Habitats’. It has become a standard resource for nursery, landscape and arborist industries in the North Central Region.
I am currently working with Dr. Cristi Palmer (Rutgers) and a team of researchers on an SCRI grant, 'Protecting Pollinators with Economically Feasible and Environmentally Sound Ornamental Horticulture’. Information generated from this research will be used to develop more detailed best management strategies for protect pollinators, and to determine which of the most widely grown annuals and perennials are good food sources for pollinators.
Michigan is currently ranked #3 in the nation in floriculture production. My lab is working with Dr. Rose Buitenhuis in Ontario, and our Extension Horticulture Educator, Heidi Lindberg, to help growers use more biological control strategies. This includes research on products compatible with the release of predators and parasitoids, and a series of educational programs to provide growers with the information and tools they need to begin relying on biological control.
- Protecting pollinators on ornamental plants
- Long-term biological control of Japanese beetle
- Development of new pest management strategies compatible with biological control in greenhouses and nurseries
- 1999 - Present - Professor, Dept. of Entomology, Michigan State University
- 1993-1999 - Associate Professor, Dept. of Entomology, Michigan State University
- 1985-1993 - Assistant Professor, Dept of Entomology, Michigan State University
- Smitley, David R., Daniel A. Herms, and Terrance W. Davis. 2015. Efficacy of soil-applied neonicotinoid insecticides for long-term protection against emerald ash borer (Coleoptera: Buprestidae). J. Econ. Entomol. 109: 1 – 10.
- Smitley, D.R. 2012. European chafer. Pp. 33 – 35 In Handbook of Turfgrass Insect Pests, Entomological Society of America, Lanham, Md.
- Smitley, D. R., Jo, Y. and I. Hudson. 2011. Association of Ovavesicula popilliae (Microsporida: Ovavesiculidae) with winter mortality of larvae and reduced fecundity of female Japanese beetles (Coleoptera: Scarabaeidae). Environ. Entomol. 40: 589 – 596.
- Doccola, J.J., D.R. Smitley, T.W. Davis, J.J. Aiken, and P.M. Wild. 2011. Tree wound responses following systemic insecticide trunk injection treatments in green ash (Fraxinus pennsylvanica Marsh.) as determined by destructive autopsy. Arbor. & Urban Forestry 37(1): 6–12.
- Smitley, D.R., J.J. Doccola and D.L. Cox. 2010. Multiple-year protection of ash trees from emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), with a single trunk injection of emamectin benzoate and single-year protection with an imidacloprid basal drench. Arboriculture & Urban Forestry 36: 206 - 211.
- Smitley, D.R., E.J. Rebek, R.N. Royalty, T.W. Davis and K.F. Newhouse. 2010. Protection of individual ash trees from emerald ash borer (Coleoptera: Buprestidae) with basal soil applications of imidacloprid. J. Econ. Entomology 103: 119 – 126.
- Rebek, Eric J., Daniel A. Herms, and David R. Smitley. 2008. Interspecific variation in resistance to emerald ash borer (Coleoptera: Buprestidae) among North American and Asian ash (Fraxinus spp.). Environ. Entomol. 37: 242 – 246.