In Oct. 1996, the San Francisco Board of Supervisors passed an ordinance that became Chapter 39 of the Administrative Code, mandating that City departments adopt integrated pest management (IPM) policies that promote nonchemical approaches to pest management and reduce or eliminate the use of pesticides. Eliminated on 1 Jan. 1997 were 1) category I chemicals (listed by EPA—most toxic; these are products marked “DANGER”); 2) cancer- or reproductive-toxicity chemicals (per State of California Safe Drinking Water and Toxic Enforcement Act of 1986); and 3) possible, probable, or definite human carcinogens (per EPA). Eliminated on 1 Jan. 1998 were category II chemicals (listed by EPA—next most toxic; these are products marked “WARNING”). Eliminated on 1 Jan. 2000 will be category III chemicals (listed by EP— relatively less toxic; these are chemicals marked “CAUTION”), except for a list to be developed by 1 Mar. 1999 of low-toxicity chemicals commonly used in IPM programs. To date, 10 exceptions have been approved. Several pesticide-free research projects have been embarked on and on-going IPM training is underway for all city employees, both technical and nontechnical. Challenges remain for pesticide regulators and pest managers in implementing policy and encouraging change.
David C. Frieders and Jackie Daries
R.G. Brumfield, F.E. Effiom and S. Reiners
Fresh tomatoes grown under three production cropping systems at the Rutgers University's Snyder Research and Extension Farm were compared for differences in yields, gross revenues, production costs and net returns. Maximum marketable yields were obtained using the Integrated Pest Management (IPM) system, followed closely by the conventional system. Yields of the organic plots were only 54 percent of the conventional yield. However, the organic plots yielded only 17 percent culls whereas the IPM plots yielded 37 percent culls. Fifty-two percent of the organic tomatoes were U.S. Number Ones, while only one third of the produce from the other two systems were U.S. Number One grade. Organic plots had lower chemical costs, but substantially higher labor costs than the other two systems.
Kenneth L. Steffen, Michael S. Dann, Jayson K. Harper, Shelby J. Fleischer, Sizwe S. Mkhize, Doyle W. Grenoble', Alan A. MacNab, Ken Fager and Joseph M. Russo
During the initial season of implementation, four tomato production systems differing in soil management, pest control practices, and level of inputs, such as labor, materials, and management intensity were evaluated. These systems were CON, a low input (no mulch, no trellising, overhead irrigation, preplant fertilization, scheduled pest control), conventional agrichemical system; BLD, a high input [straw mulch, trellising, trickle irrigation, compost fertility amendment, integrated pest management (IPM)], ecologically-oriented system that emphasized the building up of soil organic matter levels and used no agrichemicals to supply fertility or for pest control; BLD+, a system similar to BLD, except that agrichemical pesticides were used; and ICM, a high input system (black polyethylene mulch, trellising, trickle irrigation, fertigation, IPM pest control) that used agrichemicals to supply fertility and for pest control. Soil characteristics and fertility levels in the BLD and BLD+ systems were modified with extensive amendments of spent mushroom compost and well-rotted cattle manure. Levels of agrichemical NPK calculated to meet current crop needs were supplied to the CON and ICM systems, with 75% of fertility in the ICM system supplied through the trickle irrigation lines (fertigation). The BLD system had a greater soil water holding capacity and sharply reduced irrigation requirements. During a wet period, fruit cracking and evidence of water-mold root rot were significantly higher in the ICM system than the BLD and CON systems. Defoliation by Alternaria solani was greatest in the BLD system and least in the ICM system. The BLD and ICM systems resulted in a 1 week earlier peak yield compared to the CON system. The yield of No. 1 fruit was 55% to 60% greater in the BLD+ system than the other three systems, which were comparable in yield. Net return was highest in the BLD+ system, although the benefit/cost ratio was greatest in the CON system. This multidisciplinary study has identified important differences in the performance of diverse production systems during the unique transitional season.
Don C. Wilkerson, Dan R. Lineberger and Priscilla J. Files
In response to the goals set forth in Target 2000, a long-range environmental plan for the Texas/Floral Industry developed by the TAMU Nursery/Floral Management Team in cooperation with the Texas Association of Nurserymen (TAN), an interactive, World Wide Web-based integrated pest management program (hortIPM) has been developed for commercial nursery and greenhouse growers. The objective of Target 2000 is to assist growers in initiation of innovative cultural and structural practices, which will result in the following changes by the year 2000: 1) reduce water consumption to 1990 levels; 2) reduce current fertilizer and pesticide usage by 50%; 3) lower current energy consumption by 25%; 4) reduce current solid wastes from agricultural plastics by 75%; 5) develop applications for municipal wastes and composted materials for nursery and floral crop production. More so than in any other cropping system, ornamental stock producers apply pesticides on a calendar basis regardless of pest damage to prevent cosmetic injury to their crops, thus reducing their marketability. As justification for this misuse of insecticides, growers cite the extraordinary low damage thresholds associated with their crops. Nursery and floral crops producers that have better access to educational resources and recommendations may be more inclined to follow biologically sound pest management principles. HortIPM is designed as a tool to facilitate access to pest management information and enhance IPM programs already in place. Currently, hortIPM is in the developmental phase, on the cusp of release to a number of sites for preliminary evaluation.
Juan A. Villanueva-Jiménez and Marjorie A. Hoy
Florida citrus nursery growers were surveyed to learn about their citrus leafminer (Phyllocnistis citrella Stainton) (CLM) management practices as a preliminary step in developing an integrated pest management (IPM) program. All responses were kept anonymous. Survey responses from growers producing ≈4.2 million trees annually were obtained, which represents most of the estimated 5.2 million trees required to annually replant Florida groves. Large nurseries (20%) each produced ≥100,000 trees per year and jointly provided 88% of the trees produced annually. Small nurseries (80%) each produced <100,000 trees per year. The citrus leafminer was ranked the most important pest in nurseries during 1995. Pesticides used for CLM control included avermectin, azadirachtin, imidacloprid, fenoxycarb, diflubenzuron, and sulfur, in order of importance. Oil and soap also were used. Growers were concerned about the possibility that the CLM will develop resistance to pesticides. Producers potentially were willing to monitor CLM populations, switch pesticide types to improve survival of parasitoids of the CLM, and leave untreated trees inside the nursery to serve as refuges for CLM parasitoids. In order of importance, pest management advice was provided by private chemical companies, the Florida Citrus Pest Management Guide produced by the University of Florida/Institute of Food and Agricultural Sciences (UF/IFAS), UF/IFAS personnel, grower magazines, private consultants, the Florida Citrus Nurserymen's Association, and other growers.
Jeanne Briggs, Ted Whitwell, Melissa B. Riley and Tom Fernandez
This study investigated effects of two pesticide applications regimes, Integrated Pest Management (IPM), in which pesticides were only applied to affected plants when damage was noticed, and Traditional, in which pesticide applications were made on a scheduled and preventative basis, on growth and health of container grown plants. Field research was conducted at a large wholesale nursery in the piedmont region of South Carolina. An isolated portion of the nursery contained eight beds that housed 25 species of woody and herbaceous ornamentals. IPM beds were subjected to weekly in-depth scouting of indicator species, and all other plant materials in both treatments were visually checked for problems on a weekly basis. The study began in June 1998 with weekly scouting ending in late October. Monthly scouting continued through the winter of 1999. Runoff water was collected from the treatments after all pesticide applications and analyzed to determine concentrations of chemicals. Plant health was rated at study's end to allow comparison between treatments. Amounts of isoxaben detected in runoff water were 7.9 g for the traditional treatment and 0.9 g for the IPM treatment. Amounts of thiophanate-methyl and chlorothalinol were similarly lower for the IPM treatment. Preliminary results indicate that plant growth was similar for both treatments.
Oregon State University (OSU) developed an integrated pest management (IPM) program for hazelnut (Corylus avellana.) in the early 1980s, through a USDA grant. Sampling schemes and action thresholds were refined over a period of 4 years for the filbertworm (Cydia latiferreana), filbert aphid (Myzocallis coryli), filbert leafroller (Archips rosanus.), and obliquebanded leafroller (Choristoneura rosaceana), which are the most important insect pests in Oregon hazelnuts. A classical biological approach was employed in the mid-1980s when the filbert aphid parasitoid, Trioxys pallidus, was imported from Europe. Grower survey results for 1981 and 1997 showed that the amount of pesticides applied for filbert aphid control has declined by 93%. The registration of synthetic pyrethroids for filbertworm control and the use of pheromone trapping have reduced the amount of active ingredient applied in the industry by 96%. The annual cost savings to Oregon hazelnut growers due to use of the OSU IPM program are estimated at $0.5 million. Current research focuses on the use of less toxic insecticides, such as insect growth regulators for filbertworm and leafroller control. The most serious hazelnut disease, eastern filbert blight (EFB) caused by the fungus Anisogramma anomala was first reported in the Pacific northwestern U.S. in 1973. It has spread its way through two thirds of the hazelnut acreage. Current OSU IPM recommendations include preventative fungicide sprays in spring, scouting for and cutting out infections, and replacement of the most susceptible cultivars when possible. The long-term approach to EFB control is the development of EFB immune varieties.
Joseph H. Connell
Almond, [Prunus dulcis (synonym Prunus amygdalus)] planted on approximately 595,000 acres (240,797 ha), is California's largest acreage tree crop. California's Central Valley accounts for nearly 100% of the U.S. domestic production of almonds. Integrated pest management (IPM) programs that integrate cultural practices and pest and disease monitoring with selective controls have improved plant protection in almond. Methods of orchard floor management and their effects must also be taken into account. Minimizing dust reduces mites while harvesting earlier and the destruction of overwintering refugia are cultural practices that reduce worm damage. Improved methods for field sampling and monitoring have reduced the need for pesticide applications while improving timing and effectiveness of needed crop protection sprays. Selective controls have further reduced the impact on nontarget species. Augmentative parasite releases have also helped manage navel orangeworm (Ameylois transitella). Effective use of new selective fungicides will require precise application timing and greater knowledge of diseases and resistance management. A better understanding of disease life cycles leading to improved monitoring of the fungal diseases, shothole (Wilsonomyces carpophilus), almond scab (Cladosporium carpophilum), and anthracnose (Colletotrichum acutatum) have reduced fungicide applications. Future challenges include the potential loss of effective pest control products, the need to continually develop improved utilization strategies, and maintaining economic sustainability.
Alvaro del Cid, Ramiro Ortiz and H.R. Valenzuela
PRECODEPA was formed with the purpose of coordinating research and extension to improve small-farm potato production. The program involves 9 countries in North, Central America and the Caribbean with the cooperation of the International Potato Center (CIP). Research and extension work was planed based on identified bottlenecks. Work was coordinated when similar bottlenecks were identified in different regions and/or countries. The project strategies emphasized the following: training of personnel to coordinate the work between extension and research; development of integrated pest management (IPM) practices; technology generation and validation trials on farmers' fields, and market development for commercialization purposes. The success of this unique program should serve as a model for similar agricultural projects in the future.
R.W. McMahon, R.K. Lindquist, B.D. Baith, T.L. Makin and M.L. Casey
A 2-year demonstration study was conducted to compare the effectiveness of two sources of Encarsia formosa (EF) on the biological control of the sweetpotato whitefly (SPWF) (Bemisia tabaci Gennadius) on poinsettias (Euphorbia pulcherrima Wild.). Commercially produced EF were raised on the greenhouse whitefly (GHWF) (Trialuerodes vaporariorum Westwood), while the locally produced EF were raised on the SPWF. Results showed that SPWF populations were reduced considerably both years, and maximum nymph parasitism ranged from 60% to >80%. No large differences were observed in the ability of EF to control SPWF populations whether raised on SPWF or GHWF nymphs. This study suggests that there is potential for controlling SPWF populations on poinsettia by EF in conjunction with an integrated pest management (IPM) program.