Final Report for AS95-023
Environmental and public health concerns have led to public demand for critical reassessment of current pest management tactics in urban surroundings, but have not reduced high aesthetic standards for urban landscapes and recreational turf areas. Pesticides and fertilizers are important potential pollutants of surface waters in urban areas. In order for landscape maintenance firms to successfully implement IPM strategies, clients must perceive that service is being provided even when a scouting-based diagnosis calls for no chemical treatment. Therefore, both providers and consumers were targeted for educational programs on the benefits of IPM in urban landscape systems. These programs were intimately tied to research efforts developing appropriate best management strategies in the Georgia Station Research and Education Garden. A Research/Extension team of eight interdisciplinary Ornamentals Working Group participated in this effort.
Twenty mini-landscapes were constructed in the Research and Education Garden at the Georgia Experiment Station. Each mini-landscape contains woody ornamentals, annual and perennial bedding plants, and turfgrass to simulate a home landscape. Portions of each contain either woody plants alone or bedding plants alone to evaluate the effect of each type of plant material on pest susceptibility. Plots are mirror image construction to allow evaluation of the cultural variable shade . Design was a split-split plot with management strategy as the main plot, randomized with four replications.
Management strategies included
1. Full traditional management in cooperation with TrueGreen ChemLawn’s Research Facility in Douglassville, GA
2. A scouting-based application program
3. Resistant plant-based landscapes
4. Untreated control plots with susceptible cultivars and, during 1997
5. Landscapes managed using products typically available to homeowners.
Plant Material and Key Pests included:
Azaleas: ‘Delaware Valley White’ and ’Plumleaf’; susceptible and resistant, respectively to azalea lace bug, Stephanitis pyrioides (Scott)
Hollies: ‘Savannah’ and ‘Nana’ burfordii; susceptible and resistant, respectively to two lined spittlebug, Prosapia bicincta Say.
Turfgrass: ‘Common’ centipedegrass and ‘Emerald’ zoysiagrass; susceptible and resistant, respectively to two lined spittlebug.
Bedding plants: New guinea impatiens and ‘Homestead Purple’ verbena. “Resistant plants” were those that had undergone a brushing treatment in the green house prior to transfer to the landscape. Previous research had shown that this form of growth regulation may also confer pest resistance. Pests evaluated on bedding plants were aphids, mites, whiteflies, thrips, and leafhoppers.
Ground-dwelling beneficial insects, mites and spiders were monitored in turf and ornamental beds using standard pitfall traps; beneficials were also evaluated on bedding plant foliage using visual inspections. Insect populations were assessed at intervals throughout the season. Damage ratings and plant quality data were also recorded.
Population levels of azalea lace bug and two lined spittlebug were influenced by management strategy and by the cultural variable shade during 1996 and 1997. Plots based on resistant plant material had no lace bugs or spittlebugs during this study. Plots with susceptible plant materials and no intervention supported high populations of both pests. Traditional management significantly reduced lace bug numbers, while scouting-based or targeted management supported intermediate levels of key pests.
Lace bugs were more common in plots in artificial 50% shade than in full sun. Spittlebugs were more abundant in the shaded half of plots during 1996 and slightly more common in unshaded plots during 1997.
Subplot, or the presence or absence of either woody or herbaceous plant material did not affect the abundance of either pest species on woody plants, but did affect plant quality and damage ratings for herbaceous plants. Annual bedding plant quality was reduced in plots exposed to full sun, although aesthetic quality of the perennial verbena was similar in both sun and shade. Few differences in pest population numbers were noted in bi-weekly samples. Winter survival of turfgrass (centipedegrass) was influenced by both shade and management strategy during 1995/1996, but not during 1996/1997. Ground-dwelling staphylinids, carabids, cicindellids, formicids, and arachnids were similar in both sunny and shaded plots and were unaffected by management strategy.
Acceptable plant quality was achieved in traditional, targeted, and resistant plant-based mini landscapes, although chemical inputs and man-hours required to maintain aesthetic quality varied. Simple shade, without the beneficial arthropod fauna characteristic of natural overstory shade, favored the development of lace bug populations, and sometimes enhanced population development of spittlebugs. Location of mini-landscapes in the Research and Education Garden provided a forum for immediate transfer of research results to a diverse clientele.
According to EPA estimates of the pesticide industry sales and usage, pesticide users in the U.S. account for one-quarter of the total active ingredients of conventional pesticides used in the world, about 1.1 billion pounds a.i. (Aspelin 1994). Although only about 25% of the total amount of pesticides sold in the U.S. is used for non-agricultural purposes, the use of many of these in densely populated urban areas increases the perceived impact of these traditional landscape management tools.
About $12.5 billion was spent on landscape and lawn care services in the U.S. in 1993 (Seed World 1993). The number of homeowners using professional landscape services increased 29% between 1992 and 1993 and was expected to increase another 6% in 1994 (Seed World 1993). There is now tremendous consumer interest in gardening, landscaping, and hobby-greenhouse activities. In 1993, lawn care continued to rank as the lawn and garden activity with the highest level of U.S. household participation and total spending, with an estimated 52 million households spending a total of $6.4 billion for lawn care related products and equipment (National Gardening Association 1994).
Managed landscapes are characterized by a tremendous diversity of plant material and associated potential pests compared with traditional agricultural (monoculture) situations. This degree of complexity confounds attempts to develop and implement integrated pest management (IPM) strategies. While prospects for the implementation of IPM on a broad scale are good, there are limitations which must be addressed. Foremost among these are clientele expectations of imperfection-free landscapes. Concerns over potential risks to human health and the environment have led to public demand for a critical reassessment of current management tactics, but have in no way lessened the demand for high quality landscapes.
Lawn and landscape maintenance firms must contend with competition and customer relations. Clients must perceive that service is being provided even when a scouting-based diagnosis calls for no chemical treatment. Combined educational efforts by industry and university professionals will be required to modify expectations about what constitutes responsible service as well as quality landscapes. Objectives of the project were designed to respond to impediments to IPM as identified by lawn care and landscape maintenance professionals in our 1994 survey of 350 companies in the Metro-Atlanta area survey (funded by the Pollution Prevention Assistance Division of the Georgia Department of Natural Resources). Impediments to the adoption of alternative management tactics identified by the industry include that alternatives to traditional chemicals are not available, too costly, or are unreliable; IPM practices are too time consuming or are not well received by clients; and, information about pest biology is lacking. Research is needed to develop practical, effective alternative management plans for urban landscape plants.
The first objective consisted of two sub-objectives.
1 a. Determine and demonstrate the aesthetic, economic, and environmental costs and benefits associated with traditional and alternative pest management methods applied to typical southeastern landscape plants.
b. Determine the interaction the cultural variable shade with various pest management strategies.
This objective involved quantification of the inputs required to maintain landscape designs under the following management methods: (a) traditional chemical management (b) targeted pest management (c) resistant plant based management and (d) a no-intervention control.
Specific pests and plant quality were monitored closely on identical mini-landscapes under different management plans in the Georgia Station Research and Education Garden. This design included common centipedegrass turf, ‘Savannah’ and ‘Nana’ hollies, ‘Delaware Valley White’ and ‘Plumleaf’ azaleas, ‘Homestead Purple’ verbena, and New Guinea impatiens. Insect and mite pests of importance on these plants included spittlebugs affecting the turfgrass and the hollies, azalea lace bugs on azaleas, and thrips, spider mites, whiteflies, and aphids infesting the herbaceous annual and perennial components of the system.
Our lack of knowledge of the biology, ecology, and potential for enhancement of naturally- occurring beneficial organisms is particularly daunting. This objective included efforts to document the occurrence and activity of indigenous beneficial arthropods within each management regime. Currently, remarkably little is known concerning natural enemies of two-lined spittlebug and azalea lace bug, especially.
The mainstay of insect pest management in the landscape has largely been conventional chemical insecticides. Use of a pesticide often remains the only practical method to prevent significant damage to turf or amenity plants from heavy or unexpected infestations. We believe the solution to many pest management problems lies in the use of resistant plant materials for the landscape. Reluctance of the nursery industry to increase production of pest-resistant plant materials, and failure of landscape architects to recommend their use are cited as primary obstacles to more widespread adoption of resistant plants for the landscape (Raupp et al. 1992).
A great range in susceptibility among plant species and cultivars has been documented for many ornamental plant/pest combinations (Raupp et al. 1992). Our recent collaborative work has identified species and cultivars of azalea and hollies resistant to the key pests of these plants, azalea lace bug and two-lined spittlebug (Braman et al. unpub.). Preliminary research also indicates that brushing (preconditioning) of bedding plants in the greenhouse reduces thrips feeding damage and aphid infestations (Latimer Oetting 1994). This objective sought to determine and document any associated reduction in pesticide inputs related to the use of resistant plant materials in landscape beds.
Cultural practices in the landscape also profoundly affect pest abundance or the expression of injury. Very little research has addressed the response of insect pests to the many cultural factors that could be modified to reduce the likelihood of infestation. Improper placement of ornamental plants in landscapes can strongly influence their degree of pest-proneness and success in the landscape. The effect of shade as a cultural variable on pest pressure was studied in the present project.
2. Determine the feasibility of and impediments to acceptance and implementation of alternative landscape management approaches.
Research and educational efforts that assess and change the public’s tolerance of moderate levels of pest damage and willingness to pay for alternative methods of pest control are a critical need. Studies conducted on ornamental plants revealed a general pattern that the public perceives and finds unacceptable, damage or defoliation that exceeds 10% (Raupp et al. 1989). Public acceptance of alternative management as a viable service and tolerance of pest pressure was evaluated during an Ornamentals Open House which took place during 1996.
Insect pest damage to ornamentals and turf is significant. For example, Georgia experienced an estimated $130 million in losses in 1991 while control costs, primarily for chemical pesticides, included $88 million in ornamentals and $22 million in lawns and turf (Hudson et al. 1991). A recent survey of Georgia landscape architects identified pesticide use reduction as a factor affecting landscape designs and plant use over the next 5 years (Garber 1993).
In concurrent planning, our interdisciplinary Georgia Station Ornamentals Working Group also identified the continuing decline in the effectiveness, availability, and ultimate use of pesticides as a problem area both in production and landscape use of ornamental plants. Therefore, one long-term goal of the Ornamentals Working Group is to define, develop, and establish urban landscape designs that utilize environmentally-tolerant plant material combined with natural enemies and limited use of biorational pesticides (soaps, oils and microbial pesticides).
The close proximity of the Georgia Station to Atlanta, a rapidly growing urban area with a booming horticultural industry, gives this team an ideal working environment and eager clientele. The 20-county Atlanta metropolitan area has experienced an influx of over 1.2 million people between 1970 and 1990 (Hartshorn and Ihlanfeldt 1993). Landscape services add $300 million to Georgia’s economy (Georgia Cooperative Extension Service). Forty-nine percent of the landscape firms are located in the metropolitan Atlanta area and more than half of these firms have been in business for less than 11 years (Hubbard et al. 1989).
Production practices that reduce the attractiveness of bedding plants to greenhouse and/or outdoor pests should also reduce the inoculation potential of those plants in the landscape. We proposed to determine the pest management potential for integrated landscapes composed of bedding plants, perennials, woody plants and turf for sustainability of the integrated system. The following discussion briefly touches on aspects of the holistic system; plants, pest, or beneficials and current trends related to their management that are relevant to the proposed project.
The use of pest- resistant plant material will reduce the need for chemical management in the landscape. In addition, management factors such as fertilization, shade, irrigation and mulching, can increase or reduce plant resistance to insect pests and also affect pest populations in the production site or landscape (Tingey and Singh 1980). Growth regulation of greenhouse-grown bedding plants can be accomplished with chemical plant growth regulators (PGRs), or nonchemically by mechanical conditioning (brushing), drought stress, or nutrient deprivation. These treatments can affect pest problems of treated plants. Daminozide reduced aphid and mite populations on chrysanthemums (Worthing 1969). PGR effects on natural enemies have only recently been evaluated. Preliminary research indicates that brushing of bedding plants reduced thrips feeding damage and aphid populations (Latimer and Oetting 1994). Moderate but continuous drought conditioning of seedlings reduced aphid populations.
Evergreen azaleas are attacked by the azalea lace bug (ALB) (Stephanitis pyrioides), an inadvertently introduced pest. Native deciduous species are generally less prone than evergreen species to infestation and damage, though a range of susceptibility has been observed among both types (Braman and Pendley, 1992; Schultz, 1993). We can accurately predict the activity of ALB in the landscape where four generations occur in the southern region (Braman et al. 1992).
Common centipedegrass and some hollies are preferred hosts for two-lined spittlebug, although these plants are otherwise regarded as relatively pest-free. Two-lined spittlebug, Prosapia bicincta (Say), has been considered a pest of forage grasses since the early 1950s (Beck 1963, Byers 1965, Pass and Reed 1965, Fagan and Kuitert 1969). Prosapia bicincta has now become a serious pest of turfgrasses and ornamentals in the southern region (Braman 1994).
Biological or natural control is an important component of reduced-input systems. Low maintenance turfgrass areas have fewer outbreaks of insect pests than do highly maintained lawns which suggests that cultural factors negatively impact indigenous natural enemies of lawn pests (Potter and Braman 1991). The presence or maintenance of natural enemies of the identified pests in each area of the landscape must be investigated.
Objective 1 This experiment, set up as a split-split plot design with four replicates, used pest management strategies and shade as the main plots and the individual landscape beds as subplots (please see accompanying figures). The design evaluated influence of traditional chemical management, targeted biorational pest management, resistant plant-based management, and untreated controls. Management plans were imposed in cooperation with TruGreen ChemLawn Research and Development Division. TruGreen ChemLawn representatives traveled from the Technical Center South in Douglasville, GA to provide a full program of lawn and tree and shrub care, to be applied on a regular basis. Treatments for the traditional program will consisted of seven applications per year timed for maximum effectiveness. The targeted treatment plan involved monitoring based decisions and use of biological and biorational materials as needed for pest suppression. Resistant plant-based plots received a similar targeted pest management program as necessary; the difference being the alternative plant materials. A minimum distance of 6 ft separated the landscape beds within a plot and the replicate plots to minimize interactions among the plots. Each plot was 1600 ft2 with a 50% shade treatment randomly assigned to one half of each plot. Sampling include visual and trap-catch (pit-fall) monitoring of both beneficial arthropods and landscape pests and ratings of plant damage due to pests. The problem pests found on each plant species under the mixed landscape conditions versus the homogenous herbaceous or woody beds was also evaluated. Insect populations and plant damage were monitored by nondestructive scouting throughout the growing season.
Objective 2 Surveys of homeowner’s and industry’s response and willingness to pay for various management services focused on management of azalea lace bug, a key pest identified under objective 1 were conducted in place during regularly scheduled field days and at the Southeastern Flower Show and at the Georgia Green Industry Trade Show in Atlanta. These responses will provide a basis for future educational efforts to modify public acceptance of alternative management tactics.
A cooperative project among research and extension scientists at the University of Georgia in the Departments of Entomology, Horticulture, Agricultural and Applied Economics, and Research Scientists in the Research Division of TruGreen ChemLawn was conducted that evaluated the suitability and likelihood of adoption of several landscape management options.
A split-split plot design involving 20 mini-landscapes constructed in the Georgia Station Research and Education Garden was used to evaluate and demonstrate quality of landscapes based on pest resistant plants and on common pest susceptible plant materials under traditional, alternative (scouting- based, targeted biological and biorational), and no intervention pest management programs. The cultural variable of shade vs. no shade was also evaluated for potential influence on susceptibility to pests of landscape plant materials chosen for study.
Sampling at intervals assessed relative pest pressure and plant quality. Pitfall traps were used to collect ground-dwelling beneficial insects and spiders under each regime. Public acceptance of insect-induced injury, as demonstrated during field days was assessed and will form the basis for targeted educational programs designed to modify public expectation of what constitutes acceptable pest pressure. Therefore, we have addressed a major impediment to the implementation of biologically-based landscape pest management.
Treatment Regimes: Results from the first (funded) year of study have already revealed the range in pest pressure resulting from differences in management strategy including varying levels of azalea lace bug on azaleas ranging from zero infestation on the resistant Plumleaf azalea to high levels of lacebugs per leaf on our completely untreated plots. Those under traditional chemical management supported only low levels of lace bugs, while those in our targeted pest management plots had intermediate levels. Plant quality assessments of these plants also varied accordingly.
A similar range in infestation levels of two-lined spittlebugs (TLS) on hollies and turfgrass was observed among our treatment regimes. Savannah hollies in untreated plots were heavily infested and new growth especially sustained high levels of damage. Common centipedegrass in these plots was also heavily infested by immature spittlebug nymphs. Beneficial insects and spiders collected in pitfall traps, however, showed little variation in population density among these plots.
Shade effects: The cultural variable shade induced striking differences in insect infestation levels and in plant quality for several of the pest and plant combinations in this study. Spittlebugs, for example were 41X more common in shaded centipedegrass turf than in the full sun plots, consistent with unpublished dogma concerning spittlebug preference for shady sites. Azalea lace bug infestations are reputedly more severe in sunny situations. In our study they were far more common in shaded plots. Recent published studies (Trumble and Denno 1996) revealed similar observations and attribute the usual lower likelihood for understory infestations to the activity of beneficial insects and spiders that are more common in wooded habitats. Ground-dwelling beneficials in this study, however, were slightly more common in the full-sun plots. Foliar beneficials on woody plants were not measured. Spiders and ground beetles were much more often collected in turfgrass than in adjacent bedding plant areas. Ants and other beneficials were more evenly abundant.
Centipedegrass in these 20 mini-landscapes experienced severe ‘winter-kill’ during the experimental period. Only 16% of centipedegrass plots in the shade had recovered by May of this year. Recovery in sunny plots was considerably greater (39%) regardless of management regime. When all centipedegrass plots (sun and shade) were evaluated, those receiving targeted management had the best recovery (37%), followed by the untreated control plots (25%), and then those under a full program (19%). Bedding plant quality was also affected by this cultural factor. New guinea impatiens in full sun plots steadily declined in plant quality resulting in quality measurements 16 weeks post-planting that were only half of those for plants grown in 50% shade. ‘Homestead Purple’ verbena, however, was much less severely affected.
Public acceptance: Surveys during field days of growers and consumers assessed the willingness of those surveyed to purchase azaleas sustaining some lace bug damage and to recommend treatment based on damage levels. The sharpest drop in acceptance occurred with plants that displayed 10% damage. Treatment of plants sustaining this level of damage (10%) was also recomended by 55% of those surveyed. Seventy percent of those surveyed were interested in using pest control strategies that limited pesticide use. A similar percentage expressed willingness to tolerate some damage to limit pesticide use.
Conclusions: A targeted pest management approach achieved an acceptable standard of landscape quality in terms of pest infestation levels and plant quality compared to untreated landscapes and in relation to a full chemical mangement program. Monitoring activities, however for this program are time consuming and expensive in terms of trained personnel. Resistant plant materials performed extremely well in reducing the numbers of target pests in these demonstration landscapes. Cultural management considerations were amply illustrated by effects on insect pest pressure and decline in plant quality for plants placed in improper sun or shade conditions. Workshop and field day participants expressed willingness towards an increased tolerance of insect pest pressure and low levels of damage to achieve the goal of reduction in pesticide use.
Educational & Outreach Activities
The following is a list of all publications emerging from the project, including those in progress.
Braman, S.K. and J.G. Latimer. 1997. Integrated pest management for urban landscapes. Pp. 225-234 In. New developments in entomology. K. Bondari (ed). Research Signpost, Trivandrum, India.
Refereed journal articles:
Latimer, J. G., S. K. Braman, R. B. Beverly, P. A. Thomas, J. T. Walker, R. D. Oetting, J. M. Ruter, W. Florkowski, D. L. Olson, C. D. Robacker, M. P. Garber, 0. M. Lindstrom & W. G.Hudson. 1996. Prevention of pollution from pesticides and fertilizers in the ornamental horticulture industry. II. Lawn Care and Landscape Maintenance. HortTech 6:222-232.
Robacker, C. D., M. A. Florkowski, K. Braman, Y. Wang & O. M. Lindstrom. 1996. Ocena odpornosci krzewow azalii no owada Stephanitis pyrioides (Scott). Erica No. 6. Poznan Poland.
Latimer, J. G. & S. K. Braman. 1997. Reducing environmental risks from pesticides in urban landscapes: metro-Atlanta as a case study. K. J. Hatcher [ed]. 1997 Georgia Water Resources Conference UGA. Athens, GA 537-539.
Latimer, J. G. & S. K. Braman. 1997. Reducing the pollution potential of pesticides and fertilizers in the environmental horticulture industry. K. J. Hatcher [ed.] 1997 Georgia Water Resources Conference UGA. Athens, GA. 156-157.
Hubbell, B. J., W. J. Flokowski, R. Oetting & S. K. Braman. 1997. Pest management in the landscape/lawn maintenance industry: A factor analysis. J. Prod. Agric. 10:331-335.
Braman, S. K., R. D. Oetting & W. Florkowski. 1997. Assessment of pesticide use by commercial landscape maintenance and lawn care firms. J. Entomol. Sci. 32:403-411.
Braman, S. K. & J. M. Ruter. 1997. Preference of twolined spittlebug for Ilex species, hybrids, and cultivars. J. Environ. Hort. 15:211-214.
Braman, S. K., J. G. Latimer & C.D. Robacker (1998). Factors influencing use of pesticides and implementation of IPM in GA. HortTechnology . 8:145-149.
Wang, Y., C.D. Robacker & S.K. Braman (1998). Identification of resistance to azalea lace bug among deciduous azalea taxa. J. Am. Soc. Hort. Sci. 123:592-597.
Gillman, J.H., M.A. Dirr, and S.K. Braman. 1999. Gradients in susceptibility and resistance mechanisms of Buddleia L. taxa to the two-spotted spider mite (Tetranychus urticae Koch). J. Am. Soc. Hort. Sci. 124: 114-121.
Wang, Y., S.K. Braman, C.D. Robacker, J.G. Latimer, and K.E. Espelie. 1999. Composition and variability of epicuticular lipids of azaleas and their relationship to azalea lace bug resistance. J. Am. Soc. Hort. Sci. 124:
Ruter, J.M. and S.K. Braman. 1999. Twolined spittlebug damage on Ilex species, hybrids, and cultivars. J. Am. Holly Soc. (In press).
Robacker, C., K. Braman, M. Florkowska, and O. Lindstrom. Ocena podatnaœci gatunkõw I odmian azalii na Rhabdopterus picipes (Oliver)-Susceptibility of deciduous azalea species and cultivars to Rhabdopterus picipes (Oliver)- cranberry rootworm. Erica Polonica 9: 43-50.
Braman, S.K. & J.G. Latimer. 1997. Research on display: Landscape management project. Southern Nurserymen’s Association 42nd Annual Resarch Conference Report.pp 476-477.
Robacker, C.D. & S.K. Braman. 1997. Susceptibility of deciduous azalea species and cultivars to cranberry rootworm. Southern Nurserymen’s Association 42nd Annual Reseach Conference pp 335-336.
Stewart, C.D., S.K. Braman, B.L. Sparks, J. Latimer, G. Wade & J. Woodward. 1997. The ornamentals working group and integrated plant health management pilot project: progress to date. Southern Nurserymen’s Association 42nd Annual Research Conference pp. 113-115.
Klingeman, W.E. & S.K. Braman. 1997. Purchasing and pest treatment trends in azaleas: A survey of Georgia ornamental growers and consumers. Southern Nurserymen’s Association 42nd Annual Research Conference. 42:98-100.
Latimer, J.G. & S.K. Braman. 1997. Reducing the pollution potential of pesticides in commercial and residential urban landscapes. Proc. National Pollution Prevention Roundtable, Denver, CO.
Robacker, C.R., K.Braman & Y. Wang. 1997. Evaluation of azalea lace bug resistance among deciduous azaleaas. GA Green Ind. Assoc. Jour. Technology Transfer issue 8(2):48-49.
Stewart, C.D., S.K. Braman, B. Sparks, G.L. Wade & J.G. Latimer. 1997. Outline of the UGA ornamental’s working group’s pilot IPM program. GA Green Ind. Assoc. Jour. Technology Transfer issue 8(2):46.
Gillman, J., M. Dirr & S.K. Braman. 1997. Buddleia: progress towards choosing cultivars and understanding spider mite resistance. GA Green Ind. Assoc. Jour. Technology Transfer issue 8(2):18-22.
Florkowski, W.J., C. Robacker, S.K. Braman, J.G. Latimer & J. Walker. 1997. The importance of pest management services among the Atlanta metro area lawn care and landscape maintenance firms. GA Green Ind. Assoc. Jour. 8(3):20-21.
Braman, S.K.. 1997. Biological control of insects and mites Ch. 7 In J.Williams-Woodward and B. Sparks (eds) Landscape Integrated Pest Management Manual. University of Georgia.
Braman, S.K. 1997. Host Plant Resistance Ch. 8 In J. Williams-Woodward and B Sparks (eds) Landscape Integrated Pest Management Manual. University of Georgia.
Stewart, C.D., S.K. Braman, B.L. Sparks, J.Latimer. G.Wade, and J. Woodward. 1997. Integrated plant health management pilot project. . Southern Nurserymen’s Association Annual Research Conference Proceedings. 42:113-115.
Klingeman, W.E. 1998. Developing decision making guidelines for the control of azalea lace bug, Stephanitis pyrioides (Scott) (Heteroptera: Tingidae). Ph.D. Dissertation, University of Georgia, 208 pp.
Publications in review:
Hubbell, B.J., W.J. Florkowski, R. Oetting, S.K. Braman & C. Robacker. Implications of lawn care and landscape maintenance firm profiles for adoption of pest management practices. Review of Agric. Econ.
Klingeman, W.E., S.K. Braman, and G.D. Buntin. Azalea growth in response to azalea lace bug (Heteroptera: Tingidae) feeding. J. Econ. Entomol.
Klingeman, W.E., S.K. Braman, and G.D. Buntin. Feeding injury of the azalea lace bug, Stephanitis pyrioides (Scott) (Heteroptera: Tingidae). J. Entomol. Sci.
Klingeman, W.E., S.K. Braman, and G.D. Buntin. Evaluating grower/landscape manager and consumer perceptions of azalea lace bug feeding injury. J. Econ. Entomol.
Klingeman, W.E., M.W. VanIersel, G.D. Buntin, and S.K. Braman. Whole-plant CO2 exchange measurements on azaleas injured by azalea lace bug feeding. J. Econ. Entomol.
Klingeman, W.E., G.D. Buntin, M.W. Van Iersel, and S.K. Braman. Leaf and whole-plant gas exchange responses of insecticide treated azaleas. Crop Protection.
Outreach programs and events reached a broad and diverse audience in Georgia. Programs that addressed industry and professional turfgrass and landscape managers included Pest Management Scout Schools conducted at several locations within the state including the Georgia Station where more than 100 people attended on Oct. 29, 1996. The workshops were designed to provide landscape professionals with additional training in pest management for landscapes. Those attending the schools included landscape management professionals, production nursery growers, and county extension agents. The classes included instruction in insect management strategies for ornamentals and turfgrasses and a scouting, examining and identifying hands-on workshop. Schools were repeated in Morrow GA, and in Savannah.
The Ornamentals Open House, held during 1996 and again in 1998 included activities on the landscape management plots and related studies and drew an audience of general consumers and industry professionals. A separate program for K-12 youth was conducted in conjunction with the 1998 open house.
Difference in inputs required to maintain landscape designs that are pest-resistant versus pest susceptible were dramatically illustrated during this project. Both traditional and targeted management plots required substantial intervention to reduce injury caused by the key pests, azalea lace bug and two lined spittlebug. Plots (mini-landscapes) constructed with plant material resistant to these key pests required no insecticide at any time during the course of the study. An increased understanding of the pest population dynamics in an integrated system was gleaned from the project as additional data was collected on ground-dwelling predators that may potentially serve as natural control agents for spittlebugs.
A direct benefit of the proposed project was the immediate demonstration of pest susceptible and pest resistant landscapes under varying levels of management. Subsequent educational efforts related to the project will modify public perception about appropriate and responsible use of pesticides and acceptance of alternative management strategies. This will foster a reduction in pesticide application in the landscape, reduce pesticide exposure to professional applicators, homeowners and the general public, and increased public education regarding pesticide use on ornamentals.
We gratefully acknowledge the collaboration with Mark Prinster, Tom Eckberg, and Randy McQueen of TruGreen ChemLawn Research Division, Douglassville, GA. They kindly provided their time and expertise in applying the industry standard as one of our treatments in the landscape management project.
Areas needing additional study
Aspelin, A.L. 1994. Pesticide industry sales and usage: 1992 and 1993 market estimates. Office of Pesticide Programs, US-EPA, Washington, DC.
Beck, E.W. 1963. Observations on the biology and cultural insecticidal control of Prosapia bicincta, a spittlebug, on coastal bermudagrass. J. Econ. Entomol. 56: 747-752.
Braman, S.K. 1994. Two lined spittlebug; Insect management and unique control considerations; and Insect /plant stress interactions. Entomol. Soc. Am. Handbook Series. (In press).
Braman, S.K. and A.F. Pendley. 1993. Relative and seasonal activity of beneficial arthropods in centipedegrass as influenced by management practices. J. Econ. Entomol. 86: 494-504.
Braman, S.K. and A.F. Pendley. 1992. Evidence for resistance of deciduous azaleas to azalea lace bug. J. Environ. Hort. 10:40-43.
Braman, S.K., A.F. Pendley, B. Sparks, and W.G. Hudson. 1992. Thermal requirements for development, population trends, and parasitism of azalea lace bug (Heteroptera: Tingidae). J. Econ. Entomol. 85: 870-877.
Byers, R.A. 1965. Biology and control of a spittlebug, Prosapia bicincta (Say), on coastal bermudagrass. Univ. of Georgia Agr. Exp. Sta. Tech Bull. N.S. 42. 26 p.
Fagan, E.B. and L.C. Kuitert. 1969. Biology of the two lined spittlebug, Prosapia bicincta, on Florida pastures (Homoptera: Cercopidae). Fla. Entomol. 52: 199-206.
Garber, M.P. 1993. Predicting plant needs. Am. Nurseryman 177(11):53-57.
Harbaugh, B.K., J.F. Price, and C.D. Stanley. 1983. Influence of leaf nitrogen on leafminer damage and yield of spray chrysanthemum. HortScience 18:80-881.
Hartshorn, T. and K. Ihlanfeldt. 1993. The dynamics of change: An analysis of growth in metropolitan Atlanta over the past two decades. Research Atlanta, Inc., GA St. Univ., Atlanta GA.
Hubbard, E.E., J.C. Purcell, and G.L. Wade. 1989. An economic profile of the commercial landscape industry in Georgia. Research Report 573, The GA Agr. Exp. Sta., Coll. of Agr., The Univ. of GA, Athens, GA.
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