Annual Reports

1999—IPM in Action

Multiple Tactics Explored in Grape Mealybug Battle

IPM Advisor Walt Bentley and his collaborators, Farm Advisors Don Luvisi, Bill Peacock, George Leavitt, and Paul Verdegal, have had considerable success in managing vine mealybug (Planococcus ficus) and grape mealybug (Pseudo-coccus maritimus), two mealybugs that pose a serious threat to grape growing, by identifying factors that impede biological control. Walt and his collaborators have taken their research to farmers and pest control advisers through several educational programs that have focused on mapping the movement of vine mealybug, first identified in the San Joaquin Valley in June 1998. Using flowering plants and sticky barriers to exclude ants (Formica and Solenopsis spp.) from vines, this team found significantly fewer grape mealybugs and greater parasitoid abundance than on vines under clean cultivated and nonexclusion treatments. Cultural factors, such as vine girdling to increase sugar content on table grape varieties, were also found to result in higher grape mealybug populations. Understanding such relationships allows growers and their PCAs to develop local approaches to managing grape mealybug, to implement both biological and cultural controls for the pest, and to use these techniques to evaluate the need for insecticide treatment.

IPM Project Establishes Center to Evaluate the Impact of IPM Efforts

Dr. Rose Krebill-Prather likes to get people's opinions, especially on IPM topics. Dr. Krebill-Prather leads the IPM Evaluation Center located at the UC Kearney Agricultural Center in Parlier. She comes to California from Washington State University where she ran a similar laboratory while she completed her doctoral degree in rural sociology.

The Evaluation Center will develop methodologies and conduct specific studies to measure the impact of IPM extension and research efforts and of projects conducted as part of the NIOSH Agricultural Health and Safety Center and the IPM Project's Pesticide Education Program. Quantifying the impact of IPM activities is important in both planning and reporting successful projects, and is now a requirement for receiving Smith-Lever IPM funds and Pesticide Applicator Training funds from the USDA. She has already been working with Pat O'Connor-Marer to evaluate pesticide safety training programs and the series of grape IPM workshops held in the past few years. Her current projects include characterizing IPM and measuring changes in almond and cotton systems. One study that is nearing completion was conducted with UC IPM's partners in the Almond Pest Management Alliance; the Almond Board of California; the Community Alliance with Family Farmers; the California Department of Pesticide Regulation; and the Almond Processors and Hullers Association.

Walnut Pest Management Alliance Formed to Reduce Pesticide Use for Codling Moth

Codling moth has become an increasingly difficult pest for walnut growers, who have had to apply more pesticides to achieve control in recent years. The Walnut Pest Management Alliance, supported by a grant from the Department of Pesticide Regulation, was formed to test reduced-risk pesticide practices.

The Alliance consists of the Walnut Marketing Board, UC Statewide IPM Project, Biological Integrated Orchard Systems (BIOS), UC researchers, UC Cooperative Extension farm advisors, growers, PCAs, DPR, and insectaries. The Alliance is managed by a team representing each of these groups.

Three regional implementation teams allow for interaction and planning between the members of the alliance and their cooperators. IPM Advisor Carolyn Pickel coordinates the monitoring of 12 paired-comparison walnut orchards that serve as demonstration for the project. Developing and implementing a reduced-risk management program that uses a multitactic approach for codling moth could result in a major reduction of pesticides in walnuts.

UC IPM's First Interactive CD-ROM Program to Be Released

A new interactive program on CD-ROM, Solving Garden and Landscape Problems: A University of California Interactive Guide, was sent to Cooperative Extension county offices in fall 1999. This program provides high quality, peer-reviewed material to master gardeners, extension agents, and others in UC Cooperative Extension offices who respond to calls from the public about garden and landscape problems. Using this CD-ROM, UCCE personnel will be able to recommend the least toxic management solutions to hundreds of garden and landscape problems. The CD-ROM is designed to run on both Macintosh and PC; a for-sale version will be released to the general public in early 2000.

Easily the most comprehensive garden problem-solver available, the program includes over 2,800 separate screens of information and 4,800 color photos. Common pests and disorders on 40 fruit and vegetable crops and more than 80 ornamental plants are covered.

Principal authors Mary Louise Flint and Joyce Strand, both of the Statewide IPM Project, and Pam Geisel, UCCE horticultural advisor from Fresno County, initiated the project. Cheryl Reynolds, principal designer and programmer, began developing the CD-ROM in fall 1995, using UC IPM publications Pests of the Garden and Small Farm and Pests of Landscape Trees and Shrubs as a basis of information. Faculty, farm advisors, horticultural advisors, master gardeners, and retail nursery representatives, along with cooperators from Washington State University and Oregon State University, helped identify the most common pests and disorders and also tested the program and reviewed technical information.

The program was supported by the Elvinia J. Slosson Foundation; USDA-Cooperative State Research, Education, and Extension Service Regional Funds; USDA Smith-Lever IPM Implementation Program; and the UC Statewide IPM Project.

CDFA Approves UC IPM-Developed Solarization Technique against Nematode Pest Infestation

California growers urgently need usable alternatives to methyl bromide because of its international regulatory phase-out by 2005. Led by IPM Advisor and plant pathologist Jim Stapleton, a team of UC Kearney Agricultural Center scientists tested various solarization techniques for their potential to disinfest soils of certain nematode and fungal pathogens. Moistened field soils, free of roots and large organic debris and naturally infested with nematode pathogens (including citrus, root lesion, root knot, ring, and others) and with the fungal pathogen Pythium ultimum, were placed in black polyethylene (poly) planting sleeves or left in piles. The best treatment was placing soil on a sheet of poly, covering it with two layers of transparent poly film separated by wire hoops, and exposing it to the open sun. Soil temperatures reached as high as 176°F reducing nematodes to undetectable levels as determined by soil extractions and root bioassays in susceptible test plants. Results of the experiments indicated that solarization may be used commercially in nursery operations in the San Joaquin Valley and other desert areas in California. A protocol for this treatment was recently approved by the California Department of Food and Agriculture for production of container, flat, and frame-grown nursery stock.

Identifying IPM Alternatives to Improve Water Quality

In recent years, levels of diazinon and chlorpyrifos that are toxic to the small invertebrate organism Ceriodaphnia dubia have been detected in the Sacramento and San Joaquin rivers at certain times during the year. The UC IPM Project has been working with the UC Davis Center for Ecological Health Research under a grant from the CALFED Bay-Delta Program to help identify and test alternatives to these insecticides used as dormant sprays in orchards, and to alert growers to regulatory concerns as well as to the feasible alternatives.

A second component of this study focuses on large-scale urban uses of diazinon and chlorpyrifos. UC IPM staff have been working with the Urban Pesticide Committee and the Sacramento/Feather River OP Pesticide Focus Group to provide technical information on pest management and alternatives to organophosphate insecticides. Mary Louise Flint and Senior Writer Pattie Gouveia, working with UC Cooperative Extension Advisor Ed Perry and CALFED Project Manager Mike Oliver, plan to develop a matrix of feasible alternatives to diazinon and chlorpyrifos, and to initiate an outreach program in the Modesto area. This year's efforts will concentrate on identifying the key pests and users of diazinon and chlorpyrifos in the urban area.

Reducing the Risk of Pesticide Runoff

Pesticides have been detected in surface and groundwater in California. IPM Advisor Tim Prather is developing techniques that use preemergent herbicides but reduce the risk of off-site movement. Located in Fresno and Tulare counties and conducted in conjunction with Farm Advisors Neil O'Connell, Mark Freeman, and Kurt Hembree, the research involves irrigation management, herbicide incorporation, application timing, herbicide injection, reduced rates, and cover cropping in grapes and citrus. In grapes, deep percolation of simazine can be avoided by proper irrigation management and a variable application of herbicide across a berm. Also, a woven fabric weed mulch that reduces weeds in vine rows benefit vineyards that are under drip irrigation. In citrus, rates can be reduced by 50% without increasing weed populations in the fall or spring. Chemical incorporation with surfactants shows some promise but additional work is necessary. Delaying preemergent applications unitl late winter avoids major runoff periods that begin in November and continue through March. Injecting herbicides through the irrigation system allows farmers flexibility in timing applications for weed control around emitters. Runoff prone areas, particularly hillside citrus orchards, benefit from cover cropping; up to a 10-fold reduction in runoff occurred when cover crops were used. The research was funded by grants from California EPA-DPR and Kings River Conservation District.

IPM Program Fights Avocado Thrips

The avocado thrips [62K] cirtothrips perseae, is the single most devastating arthropod pest that the California avocado industry has ever had to confront. First discovered in Ventura County, the pest quickly spread throughout commercial and backyard avocado plantings from San Luis Obispo County to San Diego County. Heavy thrips levels on young spring growth have caused leaf drop, but the greatest concern is the economic loss to the crop caused by the scarring of young, tender fruit tissue. Since the thrips was a newly introduced pest, there was no research or body of literature on this insect. As a result, a team of UC Riverside and Cooperative Extension scientists has been assembled to study the problem.

As part of this effort, IPM Advisor Phil Phillips and UCCE avocado Advisor Ben Faber are actively researching the field biology of avocado thrips in Ventura County. Their current research focuses on developing an economic threshold and an understanding of thrips biology. The long-term goal is to develop an IPM program for avocado growers to manage the invader, possibly involving biological control agents and/or selective insecticides. Significant progress has already been made towards determining when pest monitoring is critical and when control measures must be applied. Phillips and Faber's research shows that damage is primarily the result of thrips feeding during the first 2 to 3 weeks of fruit development. No thrips have been observed on fruit longer than 2 inches. These findings suggest that PCAs and growers will have to monitor very carefully during this early period of growth to prevent economic damage.

New Publications Address Home, Landscape, and Floriculture Problems

The UC IPM Pest Management Guidelines series continues to expand with the publication in 1999 of a new guideline for ornamental nurseries and floriculture. This guideline focuses on floriculture diseases and targets pests of ornamentals grown in the field, in containers, and in the greenhouse. Sections on the control of insects and mites and weed management are in review and should be published in early 2000.

In 1999, 15 new publications were added to the Pest Notes series, and 10 previously published Pest Notes were updated. New publications in the series include one on the recently introduced eucalyptus redgum lerp psyillid, several new publications on weed pests, including the southern California weed green kyllinga, and a series of three publications on the management of rose pests in the home landscape. Most of the Pest Notes are 2- to 4-page publications targeting single pests found in home gardens or in the home and focus on least-toxic control methods; a few of the Pest Notes, however, are geared toward professional landscapers or range managers.

Both Pest Notes and Pest Management Guidelines are available at the UC IPM Web site and from UC Cooperative Extension offices throughout the state. Senior Writer Barbara Ohlendorf is the coordinator for both series.

Pesticide Education Program Reaches Out to Non-English-Speaking Communities

The Pesticide Education Program (PEP) is expanding its outreach program to several traditionally underserved groups, including Spanish-speaking and Southeast Asian and Filipino farming communities and other non-English-speakers. PEP is committed to educating all pesticide handlers and agricultural workers about pesticide safety issues in an effort to reduce pesticide illnesses and injuries. In California this is a large task, because it is necessary to overcome many language and cultural barriers that hinder effective pesticide training efforts in immigrant communities.

PEP is undertaking two new projects to accomplish these goals. One is a contract awarded by the Department of Pesticide Regulation to conduct a feasibility study using an English as a Second Language (ESL) approach to teach non-English-speaking pesticide handlers how to read pesticide labels. The study, which was originally developed by PEP's Farmworker Pesticide Training Coordinator Melanie Zavala, will be conducted in both Spanish-speaking and Southeast Asian populations.

The second project involves teaming up with the Pesticide Applicator Training Program in Hawaii to conduct language-specific pesticide safety train-the-trainer workshops among immigrant Southeast Asian and Filipino farming communities in both states. An ultimate goal is to facilitate new links between community leaders and educational and regulatory agencies, so that these communities may have ongoing access to important information and assistance as they establish their own ongoing, community-based training programs.

Measuring IPM Progress in San Joaquin Valley Cotton

How do we measure progress toward biologically reliant IPM systems? Regional IPM Advisor Pete Goodell is working with Fresno cotton producers to help answer that question.

Counting pest control practices is a widely suggested approach for determining the degree of IPM adoption. This approach involves listing the number of possible practices and categorizing them on a continuum from low (chemically intensive) to high (biologically reliant). One method of counting practices separates them into four kinds of activities: prevention, avoidance, monitoring, and suppression. In all, 20 practices are included in these four groups. To be considered a minimum IPM practitioner, a farmer must utilize some tactics from three out of four groups.

Results of a survey of cotton growers conducted by Pete and by Rose Krebill-Prather, who are both located at the IPM Evaluation Center at Kearney Agricultural Center, show that these growers utilize eleven practices from all four kinds of IPM activities. This number indicates that growers are using a mid-range level of IPM tactics, which is considered a mature IPM system. Practices utilized include maintaining host-free periods; selecting cultivars with tolerance or resistance to disease; scheduling irrigations to minimize late-season excessive growth; adjusting planting dates to minimize disease and insect attack; scouting twice weekly; keeping written records; using pheromones for insect monitoring; preventing seedling disease through fungicide seed treatments; using action thresholds for insect management decisions; using bean strips to mitigate insect migration; adjusting planting density to manage pests; and alternating insecticides to prevent insects from developing pesticide resistance.

Thirty UC IPM Projects Funded in 1999

Thirty research projects by UC faculty and Cooperative Extension scientists throughout the state were funded for the 1999-2000 year through the UC IPM Project Research Grants program. These include projects in applied field ecology, biological control, biorational use of pesticides and biotic agents, cultural controls, and decision support in commodities ranging from poultry houses, rangeland, and turf to tomatoes, cotton, and pears. Twelve other projects ended in 1999. The projects are detailed on the UC IPM Web site. Information about the 2000-2001 funding cycle is on the UC IPM Web site.

The cultural control of an invasive weed that threatens both agricultural and natural ecosystems in California is the topic of research being conducted by Joseph DiTomaso, UC Davis weed scientist, on the use of fire to control yellow starthistle.

A critical issue in biological control, nontarget impacts from Trichogramma is addressed in an IPM-funded project conducted by Nicholas Mills, UC Berkeley. This type of work is needed to permit biological control to remain an effective alternative approach for IPM. It is also important because it deals with a biological control organism of a major crop pest usually treated with organophosphate insecticides. Of course, organophosphates are being critically reviewed under the U.S. Food Quality Protection Act.

An example of an IPM project that is aimed at developing alternatives to methyl bromide fumigation is UC Davis Plant Pathologist John Duniway's work on developing cultural practices for management of Verticillium wilt in strawberry.

Lucia Varela Studies Environmental Policy Making at U.S. EPA

The American Association for the Advancement of Science awarded IPM Advisor Lucia G. Varela an Environmental Science Fellowship to spend a year with the U.S. Environmental Protection Agency in Washington, D.C.

The fellowship program provides an opportunity to learn how scientific and technological information is used in environmental policy making in the U.S. Environmental Protection Agency. During her year at the Biopesticides and Pollution Prevention Division of the Office of Pesticides, Lucia learned about the Pesticide Environmental Stewardship Program, whose goal is to reduce the risks from pesticide usage by promoting increased use of biopesticides and integrated pest management strategies. She worked in the Field and External Affairs Division of the Office of Pesticides developing an international training module, "Disposal of Obsolete Pesticides in Developing Countries." This course is offered worldwide to aid in the disposal of large quantities of obsolete pesticides, primarily persistent organochlorines and organophosphates.

In addition, Lucia learned how the Agency sets policy to implement the Food Quality Protection Act of 1996 (FQPA) and how it performs risk assessments to set pesticide tolerances. The FQPA has put into place requirements for better assessing the effects of pesticides in children, the aggregate and cumulative toxic effects of pesticides, and the effects on the endocrine system.

(Chart adapted from Georghiou, G. P. 1990. In Managing Resistance to Agrochemicals: From Fundamental
Research to Practical Strategies,Green et al. [eds.] Washington, D. C.: Symph. Ser. Am. Chem. Soc.)

When some pesticides are used continuously without including another method of control to reduce the pest population, resistance to that pesticide can develop. Populations may also become resistant to other pesticides that have the same mode of action. As populations shift from susceptible to resistant, there is the tendency to apply more pesticide at more frequent intervals. However, this only serves to speed up the development of resistance. The good news is that there are ways to slow down or even avoid the development of pesticide resistance by rotating pesticides from different chemical classes or different modes of action and by using nonchemical methods such as mechanical, cultural, and biological controls.

Cheryl Wilen, area IPM advisor for ornamental production and landscapes, has developed a slide set titled "Pesticide Resistance: What It Is and How to Avoid It" to help teach pesticide applicators and pest control advisers about the different types of resistance, how resistance develops in pest populations, and what steps can be taken to reduce the likelihood of pesticide resistance. Insecticides, herbicides, and fungicides are covered separately since resistance management can vary by the type of pest. This slide set, along with a script, is available from DANR Communications.

Health Care Providers Receive Training in Pesticide Exposure Cases

In response to health care providers' requests for better resources and training programs to help them diagnose, treat, and report pesticide exposure cases, Pesticide Education Program (PEP) staff traveled to Salinas in November to launch a prototype workshop titled "Extending Pesticide Information and Resources to Health Care Providers."

The workshop was initially designed and promoted for health care providers who were interested in extending pesticide information to other medical personnel. However, PEP staff were surprised to discover that the program appealed not only to physicians and clinic staff, but also to farmworker advocacy groups, growers, and workers' compensation insurance company representatives.

Workshop participants attended six interactive sessions, which included information on reporting requirements and pesticide use in California; the latest tools for medical monitoring of pesticide exposure; and reference materials for recognizing and treating pesticide illnesses and injuries. Interactive training techniques were also emphasized to help participants develop interesting and effective training programs.

Productive discussions followed the session, focusing on legal issues, workers' rights, and what really happens in these situations. "We realized there is still more work to be done to identify barriers, issues, and informational gaps faced by health care providers and their patients," said Patrick O'Connor-Marer, pesticide training coordinator. "We will continue our effort to provide not only useful workshops and resources, but to develop links among medical personnel, farmworker advocacy groups, insurance companies, enforcement agencies, and others."

Spanish-Speaking Vineyard Workers Learn about IPM

Because vineyard workers spend many hours in close proximity to the vines, they can be the first to detect a pest problem. Although many vineyard workers have experience with pests and pest management from their native countries, they may be challenged by their knowledge of the California vineyard pest complex as well as by limited English proficiency.

During the summer of 1999, UCCE Farm Advisor Mario Moratorio organized and conducted eight hands-on workshops in Spanish in four north coast counties with funding provided from the Extension Smith-Lever IPM Program and administered by the UC IPM Project. These workshops were intended to provide Spanish-speaking vineyard workers with the opportunity to review their insect identification knowledge and to apply this knowledge in the vineyard.

Topics covered included identification of major insect pests found in the vineyard; identification of natural enemies; identification of grape pests not currently in the north coast region (e.g., variegated leafhopper, Western grape leaf skeletonizer); use of a hand lens; and introduction to sampling and monitoring techniques. Upon completion of the workshop, participants were able to distinguish between natural enemies and pests, and to convey this information to farm managers and pest control advisers.

With increased reliance on IPM in sustainable farming systems, proper monitoring and identification of pests and their natural enemies are more essential than ever.

Ecological Risk Assessment Symposium

The UC Statewide IPM Project is a key participant in several research and educational projects aimed at promoting the role of integrated pest management in reducing pesticide impacts on water quality. An important role of UC IPM is to facilitate discussions between different disciplinary units of the university, private organizations, and governmental agencies (including the State and Regional Water Resources Control Boards, the Department of Pesticide Regulation, and the U.S. Geological Survey) on IPM and the environment.

One such discussion took place at the International Conference on Ecosystem Health held in Sacramento during August, where UC IPM cosponsored a symposium on "Probabilistic Ecological Risk Assessment and Best Management Practices for Surface Water Protection." The two-day symposium addressed how probabilistic ecological risk assessment methods could be employed in the development of water quality standards and total maximum daily loads (TMDLs) for pesticides in California, and sought to gain a better understanding of the research and educational needs that are necessary to address issues involving pesticide impacts on surface waters.

Speakers presented concepts and definitions of TMDLs (including a regulatory overview, availability of tools for water quality protection, and probabilistic risk assessment case studies for two pesticides, diazinon and chlorpyrifos), defined the issues associated with pesticides and pesticide TMDL development, and described programs and initiatives aimed at minimizing agricultural and urban pesticide impacts on surface water quality. The symposium's structure provided an interactive forum to discuss what additional research and educational goals are needed to address pesticide surface water impacts.

In addition to UC IPM, cosponsors for this conference included the UC Davis John Muir Institute of the Environment and Center for Ecological Health Research; Society of Environmental Toxicology and Chemistry; Western Crop Protection Association; and Ecology and Environment, Inc.

PestCast Update: 1999 California Tomato Network

Blackmold and powdery mildew forecasts, an improved late blight model, and harvest forecasts for new tomato varieties are expected from recent work by UC advisors and specialists, Campbell Soup Research, and California Tomato Research Institute. In the 1999 growing season, UC IPM supplied 7 of 16 weather stations that comprised the California Tomato Network, in its fourth season of operation.

Hourly and daily weather data from stations placed in tomato fields across the southern Sacramento Valley were automatically collected, quality controlled, and stored each day, to be used by researchers and growers. Six late blight models are being compared to see which is most promising for California, and data collected in variety trials will be used to update a processing tomato phenology model that was developed in the mid-1980s using data from older varieties. Many growers are already using disease severity values, or DSVs, calculated from the weather data to forecast the need for blackmold sprays, and the data are also useful for predicting powdery mildew.

To access the weather data or for information on PestCast crop disease modeling projects, see UC IPM Funded Projects on our Web site.

Combating a New Invader: The Eucalyptus Lerp Psyllid

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