For a decade, the main battle in America’s fields and orchards has been a chemical war on farming pests. But the pesticide war record is like Vietnam. While pesticide use has risen, crop losses to pests have not declined and public concern is on the rise. Now the war is at a crossroads.
At this important juncture, many farming operators are giving up on bombing the enemy and are turning instead to Mother Nature’s managers, integrated pest management (IPM) specialists who rely primarily on biological and ecological interventions, such as using the pests natural enemies and resistant varieties. Even the federal government, usually slow to take a new road, has placed an IPM freeway on-ramp at the crossroads. California farmers are directing traffic up this on-ramp, according to a new Consumers Union (CU) book, Pest Management at the Crossroads, (PMAC) by Charles M. Benbrook.
The release of PMAC marks the beginning of what CU promises will be an ongoing, several year effort to change the way pests are managed in America -- both in agriculture and urban settings. The 288-page book is the most complete look yet at IPM in a total and up-to-date context, while managing to be both proactive and interesting. It provides a first-ever analysis of the impacts of regulation on overall pesticide risk levels, and concludes that risks today are just as high, if not higher than the late 1960s -- the heyday of regulation. The book is loaded with over 150 pictures and graphics, and interesting facts about pest management systems and their performance, including many in California.
The book sets out a "roadmap" for change so that we will all become Mother Nature’s managers over the next 25 years. To this end the book will be used to help focus the efforts of a broad coalition of growers, pest management professionals, consumers and environmentalists committed to advancing biointensive IPM. In an interview, Benbrook points out that "USDA has tried for three years -- and failed because of opposition in Congress -- to change the focus and direction of its programs impacting pest management. We hope PMAC will help convince a wide coalition of groups to work together in breaking the logjam in the next Congress."
The need for this coalition-built change is highlighted in this telling passage: "If USDA’s $64-billion annual budget were sliced into 2,000 pieces, one [slice] would represent biointensive IPM research and education funding -- a meager investment given that 30 percent of total U.S. agricultural production is still lost to pests and that rising reliance on pesticides poses serious risks to the environment and public health, as well as agricultural sustainability in many regions."
To prod this shift PMAC purposes and CU endorses a number of multiple strategies. Key among them are:
Mother Nature’s managers have already cleared a path for this freeway to follow. Today, most of the innovation in pest management is occurring on farms, especially in California and the Pacific Northwest, but throughout the United States.
But giving Mother Nature a helping hand is not new, at least not in California. A number of beneficial insects have been used to control citrus red scale, with considerable success, over the last 50 years in Southern California. As a result, insecticides have been needed on only about 1 percent of the region’s citrus acreage to control California red scale. Today it is estimated that parasitoids are released on about one-third of California’s citrus acreage.
This marked the beginning of what would be a new industry in California. Begun in the 1970s, the California pesticide regulatory program issued its first compilation of suppliers of beneficial organisms in 1979. Today industry sales are estimated at between $20 million-$50 million per year.
From this early beginning, California has been at the vanguard of change toward biologically based pest management. A few among the many leaders of change include pear growers and leaders of the Randall Island Project, the University of California, California Clean Growers, the Biologically Integrated Orchard Systems Project, the Lodi-Woodbridge Winegrape Commission and Cal-EPA's Department of Pesticide Regulation (DPR).
It should be added that USDA Deputy Secretary Richard Rominger, a Woodland farmer, has led the federal effort at USDA to shape and pursue a national IPM initiative. His farming sons Rick, Charlie and Bruce, actively practice and promote biologically based farming systems.
The pear farm run by Doug and Cathy Hemly near Cortland is part of the Randall Island Project (RIP), one of the nation's most successful farmer-driven participatory IPM research and demonstration projects. Success in reducing reliance on Guthion, an organophosphate insecticide used to control codling moths, earned the project an "IPM innovator" award from DPR. Several Randall Island Project team members, some involved since the early 1980s, are active in refining biointensive IPM. Growers involved in addition to Greene & Hemly, Inc. include David Elliot and Sons, Inc., Wurster Ranch, Frieders Orchards and Lincoln Chan Farms.
But managing Mother Nature takes teamwork and the success of RIP extends beyond farm owners. In fact, it is a public-private partnership in all phases and aspects of technology development, refinement and delivery to the field. Mother Nature's managers of RIP include more than a dozen professionals from private industry, university specialists, grower groups, independent and pest industry consultants, technical reps and state government.
The codling moth is the most economically damaging insect species to plague pear and apple growers in California, the Pacific Northwest and around the world. The moth does its damage during its worm stage as it matures inside the fruit.
Codling moth mating disruption (CMMD) involves placing small twist-ties impregnated with codling moth pheromone (a scent released by the female moth) about 10 inches long up high in the trees. It takes about 400 twist ties per acre to fill an orchard with enough scent to thoroughly confuse the male moths. Under most conditions, an application last 100 days, so on any single day, a few one-hundredths of an ounce is released into the orchard. It is highly specific to just one species and is non toxic to farmworkers or the environment.
The Hemlys and other Randall Island growers have had to use one or two applications of Guthion or other insecticides to augment mating disruption, but this is much less than half the quantity of Guthion used in the late 1980s. Independent pest-control consultant Pat Weddle found in a study for CU that farmers using this biointensive IPM system were generally able to reduce pesticide use from about 35 pounds of active ingredient per acre under conventional systems to 13 pounds. Under biointensive IPM, pear yields typically reached the 12- to 25-tons per acre range, depending on the density of trees and orchard health. THis yield is well above the 10- to 15-ton average yields harvested under conventional management systems.
As with many biointensive IPM systems, cost is a concern and in some cases, a constraint. The codling moth pheromone active ingredient is expensive to make and available from only one firm. Placing 400 twist-ties per acre is far more labor intensive than driving through an orchard with a sprayer, which costs just a few dollars per acre. Also, mating disruption, like most biopesticide-based approaches, has to be carried out with skill and attention to detail. These steps require time, effort, experience and money.
Several technical refinements in the CMMD system are under active exploration. Scientists and IPM experts in the Northwest, for example, are working with customized aerosol dispensers linked to weather stations and mini-computers. Together with field scouting data on population levels, such a system could make it possible to reduce pheromone costs and increase efficacy. PMAC describes the future of CMMD as an example of "precision farming at its best."
As these refinements and the Randall Island Project suggests, information is a common denominator in all successful biointensive IPM systems. In general, the more pest managers rely on biology and prevention, the greater their need for information, coupled with timely and proper translation of that information into field-based action. Computers and telecommunications are lowering the cost of obtaining, analyzing and acting on information about pests, natural enemies, the weather and other factors affecting the performance of pest management systems.
PMAC states: "Farmers and other pest managers possess valuable experience which, when systematically tapped and shared with other farmers and pest managers seeking solutions to similar pest problems, can rapidly accelerate progress along the IPM continuum." The book challenges USDA and the land- grant university system to build on the Internet-based "National IPM Network," a system drawn upon and praised throughout the book, by tapping into and sharing the "enormous well of on-farm innovation" in pest management systems.
In partnership with the University of California Statewide IPM Program, growers in Napa, Sonoma and Kern counties have pioneered use of automated weather stations linked to computers and disease forecasting models developed over many years of effort by teams of U.S. researchers. The Statewide IPM Project is working to replicate such networks in all major fruit and vegetable producing regions. State and federal grants have supported this effort because of the potential to reduce reliance on fungicides.
Campbell Soup Co., a project collaborator in California, has made great strides in Mexico, California and Ohio in applying disease forecasting models in tomatoes, potatoes and other crops over 20,000 acres. Campbell’s records show that across this acreage fungicide applications have been reduced more than 50 percent -- from around 10 applications per acre to about four. One of the strengths of Pest Management at the Crossroads is that it displays dozens of World Wide Web (WWW) sources for IPM information. But it asks for more, noting that there is a bias toward insects and relatively little information on plant diseases and even less on weed management on the Internet. Information on pesticide impacts on beneficials, performance of forecasting models and trends in resistance are among the topics lacking, but well-suited to Internet dissemination.
Practicing what he preaches, author Benbrook has developed a World Wide Web site to discuss the issues addressed in the book. The Pest Management at the Crossroads web page can be found at http://www.pmac.net, and contains interesting sections on the book, "IPM in the Field", "IPM and Policy" and the recently passed "Food Quality Protection Act." The web page previews CU reports-to-come and offers, as you might expect, an easy way to order the book.
Biotechnology could also enhance the understanding and viability of biointensive IPM systems. But a review of new characteristics associated with genetically engineered crop varieties planned for introduction by the year 2000, show that only three plants engineered for virus resistance may be compatible with biointensive IPM. In contrast, 20 plants are engineered to be compatible with chemically intensive farming systems.
In the recommendations chapter, PMAC takes a hard line on applications of biotechnology. It calls on EPA not to approve any more, and pull back recently approved, registrations of Bt-transgenic plant varieties and plants engineered to resist herbicides, if there is credible evidence of resistance in the field. This recommendation is bound to face strong opposition from companies just now marketing transgenic plant varieties. Given serious control problems with Bt-cotton this year, and the emergence of weeds resistant to Roundup, this book is not the first red flag raised about how biotechnologies are to be used in the future.
It is clear that a central feature of biointensive IPM success is a reliance on information for making timely management decisions. What is not so clear, however, is what exactly IPM is and where do pesticides fit into an IPM program? Some, for example, argue that IPM is being practiced when pesticide use is cost effective or a herbicide tolerant or a Bt-transgenic plant variety is planted.
Pest Management at the Crossroads argues instead that IPM systems fall along a continuum of adoption: No IPM (pest management that is largely reliant on chemical control); low IPM; medium IPM; and high or biointensive IPM. The defining characteristic of each level is the extent to which ecological and biological IPM methods are relied upon compared to reliance on pesticides. High end, or biointensive IPM is defined as:
"A systems approach to pest management-based on an understanding of pest ecology. It begins with steps to accurately diagnose the nature and source of pest problems, and then relies on a range of preventive tactics and biological controls to keep pest populations within acceptable limits. Reduced-risk pesticides are used if other tactics have not been adequately effective, as a last resort and with care to minimize risk."
"Our emphasis on designing IPM systems with minimal pesticide reliance is not based on a judgement that all pesticides are hazardous or ecologically disruptive," Benbrook elaborates. "Healthy and sustainable-farming systems tend to be both biologically balanced and diverse. The need to apply pesticides reflects imbalance among species and pesticide use can often make matters worse, since most pesticides, especially insecticides, are toxic to many organisms beside the target pest."
Thus, biointensive IPM systems must evolve in step with new pests; changes in the economics of crop production, tillage and planting systems; technology and many other factors. Systems that work in one region often will not in others. Mother Nature’s managers must be ever alert and flexible to damage, weather, markets and their linkage to the cycles and productivity of the system as a whole.
It is estimated that about 6 percent of U.S. crop acreage is currently managed with high (biointensive) IPM, and another 25 percent is now under medium IPM. PMAC proposes to raise the bar so that acreage under biointensive IPM would double by the year 2000, that 75 percent should be in "high" and "medium" by the year 2010, and essentially 100 percent should achieve the "high" range by the year 2020. Perhaps more than anything, Mother Nature’s managers have taken a mind- set and attitude turn at the crossroads. Now they are field, soil, insect and disease "systems" managers, not the bug and disease "spray control" managers of the past.
