HORTICULTURAL ENTOMOLOGY Comparing an IPM Pilot Program to a Traditional Cover Spray Program in Commercial Landscapes COLIN D. STEWART,1 S. KRISTINE BRAMAN,2 BEVERLY L. SPARKS,2 3 4 5 JEAN L. WILLIAMS-WOODWARD, GARY L. WADE, AND JOYCE G. LATIMER University of Georgia, GrifÞn, GA 30223Ð1797 J. Econ. Entomol. 95(4): 789Ð796 (2002) ABSTRACT An integrated pest management (IPM) pilot program for landscape plants was imple- mented during 1997 and 1998 on two commercial, two residential, and one institutional property managed by landscape professionals. When compared with preprogram, calendar-based cover spray program costs at these sites in 1996, the IPM program was cost-effective at one of the Þve sites in both 1997 and 1998, and cost effective at a second additional site in 1998 when the cooperator, initially skeptical of IPM, discontinued calendar-based cover sprays performed in 1996 and 1997. The mean cost per site was $703.40 (preprogram), $788.26, and $582.22 in 1996, 1997, and 1998, respectively. Volume of pesticide applied decreased a mean of 86.3% on the four sites not receiving cover sprays and increased 2.3% at site 2 (still using cover sprays) in 1997. In 1998, pesticide volume was reduced an average of 85.3% at all Þve sites compared with preprogram levels. The majority of insect pest problems were corrected using spot sprays of insecticidal soap or horticultural oil or by physical means such as pruning. One-third of the woody plant material on the commercial and institutional sites consisted of holly, juniper, and azalea. The most prevalent pests encountered were mites (Tet- ranychidae), aphids, lace bugs, scales, whiteßies, and Japanese beetle. Spiders were the most abundant group of predatory arthropod and ants, green lacewings, and lady beetles were also well represented in the managed landscapes. KEY WORDS integrated pest management, landscape, key plant, beneÞcial arthropods, pesticide use, spiders URBAN PLANTS ARE typically considered to be high value calendar sprays to time pesticide application, whereas and people attach great value to their upkeep (Hart- 55% made applications at the customerÕs request (Bra- man et al. 1986). Most urban residents believe that man et al. 1997). Only 46% of the surveyed Þrms arthropod feeding damage on landscape plants has a monitored pest populations. Cover sprays were the major impact on the quality of life (Paine et al. 1997) method-of-choice of arborists in the urban landscape and they spend a large amount of money maintaining in Illinois (Neely et al. 1984). the plantsÕ health and esthetic appearance. More than There is general agreement that public concern $1 billion per year is spent on commercial arboricul- over pesticide use is a driving force for increased ture for pruning, applying pesticides, and tree removal integrated pest management (IPM) adoption in urban (Neely et al. 1984). Pest control is a major function of areas (Koehler 1989). There is enough information landscape maintenance Þrms (Garber and Bondari available for arboriculture companies to begin effec- 1996). In 1993, 159 Þrms surveyed in the 20 county tive IPM programs and replacing cover sprays metropolitan Atlanta, GA, area purchased 13,210; (Nielsen 1989). In successful landscape IPM pro- 3,867; and 93,447 kg of active ingredients of insecti- grams, control measures were implemented by either cides/miticides, fungicides, and herbicides, respec- a contractor (Smith and Raupp 1986), the sponsoring tively (Braman et al. 1997). Thirty-two percent of the arboriculture company (Holmes and Davidson 1984), Þrms surveyed in the metropolitan Atlanta area used the homeowner (Hellman et al. 1982, Raupp and No- land 1984), or on-campus groundskeepers (Raupp and 1 Department of Entomology, University of Georgia, 1109 Experi- Noland 1984), but site monitoring was done entirely ment Street, GrifÞn, GA 30223Ð1797. Current address: University of by University personnel. Maine Cooperative Extension, 491 College Ave. Orono, ME 04473. Large or corporate Þrms in the metropolitan Atlanta 2 Department of Entomology, University of Georgia, 1109 Experi- area are more inclined to use nonchemical control ment Street, GrifÞn, GA 30223Ð1797. 3 Plant Pathology, University of Georgia, Athens, GA 30602. than small or independent Þrms (Hubbell et al. 1997) 4 Horticulture, University of Georgia, Athens, GA 30602. and 40% of the small Þrms surveyed predicted an 5 Virginia Tech Department of Horticulture, Blacksburg, VA 24061. increase in the use of pesticides in the future (Garber 0022-0493/02/0789Ð0796$02.00/0 ᭧ 2002 Entomological Society of America 790 JOURNAL OF ECONOMIC ENTOMOLOGY Vol. 95, no. 4 and Bondari 1996). Small Þrms were not as aware of sprays in addition to making additional pesticide ap- the available IPM products and information as were plications recommended by the landscape monitor medium and large Þrms. These Þrms requested work- (scout) in 1997. In 1998, this cooperator discontinued shops focused on IPM practices, seasonal newsletters, the cover sprays and implemented the scouting-based IPM reminders, increased public education, and “fre- IPM program. The program provided training, joint- quent on-site consultation” (Garber and Bondari scout cooperator monitoring, management recom- 1996). Forty-six percent of these Þrms cite lack of mendations, scouting tools, a reference guide (Wood- information on pest biology, whereas 66 and 73% cite ward and Sparks 2000), and pocket-sized cards for the lack of availability or ineffectiveness of alterna- arthropod and disease identiÞcation. The landscape tives to traditional pesticides as impediments to IPM monitor also prepared a collection of 50ϩ beneÞcials, implementation, respectively (Braman et al. 1998). other nontargets, and key pests for each cooperator. The IPM Pilot Project was designed to meet the Cooperators were taught to assess pest problems and needs of these small Þrms by evaluating IPM practices evaluate control measures in 1997 and 1998. In 1999, with a select group of landscape professionals. The joint scout-cooperator monitoring was discontinued objectives were to compare the costs of traditional and the scout served as an information resource, mak- pest management programs (calendar-based cover ing occasional site visits. sprays) to an IPM program, compare pesticide use, Plant Composition. The location and identiÞcation assess the appearance of the clientsÕ properties, de- (genus, species, and cultivar, when possible) of key termine the sitesÕ plant composition, assess key pest plant material at each site was mapped. Con-speciÞc and beneÞcial arthropod occurrence, better reÞne plant material with a continuous canopy was por- monitoring efforts, and demonstrate IPM techniques trayed as one plant unit (Raupp and Noland 1984). to the cooperators at their places of business for in- Key Pests and Beneficial Arthropods. Woody orna- corporation into management of their other proper- mentals were sampled bi-weekly for arthropod, patho- ties. These techniques included scouting for pest and gen, or abiotic stress, and beneÞcial arthropods from beneÞcial arthropods, soil sampling and fertilization, 9 April to 27 August 1997 and 26 March to 8 September using properly-timed spot sprays directed at the pestsÕ 1998. With the exception of the red imported Þre ant, most vulnerable stage, using lower toxicity pesticides Solenopsis invicta Van Buren, turf pests and diseases such as horticultural oils and insecticidal soaps, using were not monitored. Sampling tactics varied to ac- cultural controls such as pruning, and replacing highly commodate the diversity of plant material. Large susceptible plants with nonsusceptible or resistant shrubs (Ͼ1.5 m high) at all locations and tree-form plants. Burford hollies (Ilex cornuta ÔcanariensisÕ Poiret) at one commercial site (due to a dense canopy) were scouted by taking three beat samples over a 40 by Materials and Methods 20-cm white enamel pan. One beat sample was taken Site Selection. In 1996, County Extension Agents from small shrubs (Ͻ1.5 m high). Magnolias (Magnolia assisted in selecting Þve landscape sites located in x soulangiana Soulange-Bodin and M. stellata Siebold Clayton, Coweta, Fayette, and Pike Counties in Geor- & Zuccarini) were scouted by performing one, 30-s gia. All were established landscapes installed before foliar exam. Five, 30.5-cm branch terminals and the 1996 and contained a high degree of plant diversity. accompanying foliage from hemlock (Tsuga canaden- Sites were Ϸ0.2Ð0.4 ha or possessed a readily identi- sis (L.) Carriere.) and birch (Betula nigra Michaux Þable section of similar size. Commercial, residential, and B. papyrifera Marsh) were visually examined, as and institutional sites were included to provide a range were three terminals from all other trees. in type of client properties. All properties were man- The Þrst instar (crawler) is the most vulnerable aged by landscape professionals implementing calen- scale insect stage to contact insecticides because it dar-based cover spray programs. Three additional does not have the protective wax cover characteristic sites, for a total of eight properties (two of which had of later instars (Kosztarab 1996). Stem-infesting scale received no cover sprays) were scouted for 1 yr (1998) insects were monitored for crawlers by attaching dou- to educate cooperators and to obtain data on pest and ble-backed sticky tape to branches near female scales beneÞcial insect activity. or through direct observation of crawler activity. Fo- Pilot Program. Cooperators (landscape