Research Accomplishment Reports 2010

Biology and Management of Insects Attacking Turf and Woody Landscape Plants

D.A. Potter
Department of Entomology

 

Non-Technical Summary

Rapid urbanization in the USA during the past 50 years has increased the need for safe, effective management tactics for insect pests of landscapes and turf. Concerns about environmental impact and hazard of chemical pesticides, and loss of insecticide registrations have fueled this demand.

Pests such as root-feeding white grubs, Japanese beetles, scale insects, wood borers, and leaf-feeding caterpillars cause extensive damage to lawns, landscapes, nursery crops, street trees, parks, and golf courses, amounting to hundreds of millions of dollars in economic loss.

This project will develop new methods for dealing with insect pests of urban landscapes, and contribute better understanding of pest biology upon which future control strategies can be built. The project focuses on biological and cultural control, host plant resistance, and other sustainable tactics.

2010 Project Description

Ecotoxicology of a new class of reduced-risk turf and landscape insecticides (anthranilic diamides) versus prevailing insecticide chemistries (nicotinoids, pyrethroids, and combination products) was evaluated. Unlike the older insecticides, the new chemistry had no measurable adverse effects on predatory insects, earthworms, or soil decomposers, and was compatible with biological control of pests and breakdown of clippings and thatch. Because it is non-toxic to ants and earthworms, however, transitioning to the safer chemistry could result in some resurgence in casting and mounding problems with those secondary pests on golf courses.

A by-product of tea oil manufacture was shown to be highly effective for reducing problems caused by excessive earthworm casts on golf courses and sport fields, leading to a business agreement between UK and a manufacturer of organic fertilizers to market a product beginning in early 2011.

Field sampling and feeding studies confirmed that increased use of "livestock-friendly" improved tall fescue forages having soft texture or lacking ergot alkaloids will not aggravate problems with grass-feeding insects. Those grasses also were compatible with a baculovirus that is important in naturally dampening outbreaks of armyworms. Endophytic lawn grasses that are resistant to many insect pests were shown to be compatible with biological control of cutworms by some types of parasitic insects, but not with others, helping show how non-chemical tactics can be integrated for sustainable pest management.

Twelve species of perennials were screened for attracting beneficial wasps that parasitize green June beetle grubs, and several dozen species of Dutch-elm disease-resistant elms, magnolias, and oaks were evaluated for multiple pest resistance.

A new invasive elm pest, a leaf-notching and root-feeding weevil, was discovered (a new State record) and studies of its biology were initiated.

Members of my lab presented 29 outreach talks to many hundreds of attendees at the KY Turfgrass Council, KY Landscape & Nursery Association, and Central KY Ornamental and Turf Association's Annual Conferences, Winter Workshops, and/or Summer Field Days, as well a numerous out-of state conferences attended by turf and landscape practitioners.

2010 Impact

Our research is influential in supporting the US turfgrass industries' transition to classes of insecticides that are non-hazardous to people, bees, birds, fish, natural enemies, and the environment. In 2010 I received the US Golf Association's Green Section Award, given to one individual per year for lifetime service to industry, and our work in conservation biological control was profiled in three articles in their national magazine.

Our work on baculovirus suppression of turfgrass pests provides groundwork for developing organic pest control approaches for lawns, golf courses, and sport fields. Indeed, we have been contacted by two companies interested in commercialization of the KY-discovered virus.

Our work on earthworm mitigation was deemed "intellectual property" by the University and has led to a cooperative agreement to commercialize a product.

Our tall fescue work provides assurance that, at least from an entomological standpoint, improved tall fescues being developed collaboratively by UK scientists and the USDA Forage-Animal Production Research Unit (FAPRU) will not result in greater pasture losses from insects.

Our elm, magnolia, and oak evaluations are helping nursery growers, landscapers, and homeowners to choose tree cultivars that are resistant to insect pests and will not need to be regularly sprayed, reducing chemical inputs and costs.

We have published our work in high-impact refereed journals, book chapters, trade magazine articles, and University extension bulletins, and spoken directly to literally thousands of end-users helping to bring UK research directly into practice.

2010 Publications

Bixby, A.J., Potter, D.A. (2010). Influence of endophyte (Neotyphodium lolii) infection of perennial ryegrass on susceptibility of the black cutworm (Lepidoptera: Noctuidae) to a baculovirus. Biological Control, 54: 141-146.

Potter, D.A., Redmond, C.T., Meepagala, K.M., Williams, D.W. (2010). Managing earthworm casts (Oligochaeta: Lumbricidae) in turfgrass using a natural byproduct of tea oil (Camellia sp.) manufacture. Pest Management Science, 66: 439-446.

Condra, J., Brady, C., Potter, D.A. (2010). Resistance of landscape-suitable elms to Japanese beetle, gall aphids, and leaf miners, with notes on life history of Orchestes alni and Agromyza aristata in Kentucky. Arboriculture & Urban Forestry, 36:101-109.

Hammons, D.L., Kurtural, S.K., Potter, D.A. (2010). Japanese beetle defoliation reduces primary bud cold hardiness during vineyard establishment. American Journal of Enology and Viticulture, 61(1), 130-134.

Hammons, D.L., Kurtural, S.K., Potter, D.A. (2010). Impact of insecticide-manipulated defoliation by Japanese beetle (Popillia japonica) on grapevines from vineyard establishment through production. Pest Management Science, 66: 565-571.

Hammons, D.L., Kurtaral, S.K., Potter, D.A. (2010). Phenological resistance of grapes to the green June beetle, an obligate fruit-eating scarab. Annals of Applied Biology, 156: 271-279.

Vanek, S.J. and D.A. Potter. (2010). An interesting case of ant-created enemy-free space for magnolia scale (Hemiptera: Coccidae). Journal of Insect Behavior, 23: 389-395.

Bixby-Brosi, A.J. and D.A. Potter. (2010). Evaluating a naturally-occurring baculovirus for extended biological control of the black cutworm (Lepidoptera: Noctuidae) in golf course habitats. Journal of Economic Entomology, 103:1555-1563.

Vanek, S.J., Potter, D.A. (2010). Ant-exclusion to promote biological control of soft scales (Hemiptera: Coccidae) on woody landscape plants. Environmental Entomology 39(6) (in press).

Redmond, C.T., Potter, D.A., (2010) Incidence of turf-damaging white grubs (Coleoptera: Scarabaeidae) and associated pathogens and parasitoids on Kentucky golf courses.

Bixby, A.J., Potter, D.A. (2010). Season-long biological control of black cutworms. US Golf Association Green Section Record. March/April. 11-13.

Redmond, C.T., Potter, D.A. (2010). Continuing the search for biological control of white grubs. US Golf Association Turfgrass & Environmental Research Online 8(8):1-8.

Vanek, S.J., Potter D.A. (2010). Ant exclusion for sustainable management of soft scale outbreaks on woody landscape plants. UK Nursery/Landscape Program Research Report. UK-PR 602, pp. 13-15.

Vanek, S.J., Potter D.A. (2010) Host plant resistance among Magnolia spp. and Quercus spp. to soft scale pests. UK Nursery/Landscape Program Research Report. UK-PR 602, pp. 16-18

Hartman, J., Dixon, E., Potter, D.A., Hart, J., Fountain W. National elm trial, Kentucky data, 2009. UK Nursery/Landscape Program Research Report. UK-PR 602, p. 19.