Social Factors and Selective Technology Adoption - Practicing ...

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Human Organization, Vol. 51, No. 4, 1992 Copyright @ 1992 by the Society for Applied Anthropology 0018-72591921040367-12$!7011

Social Factors and Selective Technology Adoption: The Case of Integrated Pest Management ANNE-MARIE RIDGLEY and STEPHEN B. BRUSH The adoption of most introduced technologies is limited and often partial, even when their benefits have been proven through research and experimentation. This study illustrates the extent to which farmers are selective and adaptive in their adoption of Integrated Pest Management (IPM) practices for pears in California, USA. Adoption was studied in relation to five social factors: education, influence of agricultural extension, market strategy, farm diversity, and farm type (business or family). The incidence of selective adoption can have important consequences for the success or failure of agricultural technologies and should be a subject for adaptive research by social scientists. Key words: technology. pest management, farm type


NTERNALLY GENERATED INNOVATION and invention are inherent parts of all farming systems, and have historically accounted for much technological change in agriculture (Ruttan 1984). The diffusion of externally generated innovations, however, now plays a significant role in the process of technological change as a result of the development of national and international research and extension systems (Biggs and Clay 1981). The enormous initial success of such induced innovations as hybrid seeds, both in the United States and as a part of the green revolution technologies, led to a widespread belief that all farmers would and should eventually adopt these newly introduced technologies. Most innovation diffusion research categorized farmers as adopters or non-adopters of a particular technology with no grey area between (Feder, Just, and Zilberman 1985; Rogers 1983). Those fanners who were non-adopters were considered either irrational, ignorant, or resistant to change (Merrill-Sands 1986). Decades of research by anthropologists and other social scientists on the adoption of agricultural technology have dispelled

Anne-Marie Ridgley received an MS in International Agricultural Developmentfiom the Universityof California, Davis (1991).Stephen B. Brush is Associate Professor of Applied Behavioral Sciences at the same university. Funding was provided by the University of California Statewide Integrated Pest Management Project. The authors thank the pear growers of Sacramento and Lake counties for their full cooperation. Thanks also to Daniel Mountjoy, Heather Lee Jersild, William Barnett, Rachel Elkin, Greg e e l , Patrick Weddle, Broc Zoller, Mary Louise Flint, Milton Schroth, and Margaret Brush for their advice and assistance in this research. The authors take full responsibility/or the data and their interpretation.

the notions that non-adopters are irrational or that diffusion is explained by single socio-economicfactors. The adoption of most introduced technologies is limited and often partial, even when the benefits of the new technologies have been proven through agricultural research and experimentation. Recognition of this factor has sparked a renewed awareness of indigenous knowledge systems and farmers' capacity for experimentation and adaptation (Gladwin 1989, Merrill-Sands 1986). More researchers now accept the proposition that an understanding of local knowledge and informal experimentation is an essential element in the development of agricultural technologies (Brokensha, Warren, and Werner 1980; Byerlee and Collinson 1980; Gladwin 1989; Rhoades 1987; Rhoades and Bebbington 1988; Shaner, Phillips and Schmehl 1982; Tripp 1985). This type of adaptive research is being utilized more and more frequently as a means of developing innovations that are better suited to the particular needs of the farmers they are designed to help, especially in heterogeneous social, economic, and agricultural environments, and among resource-limited farmers. An understanding of the partial and selective nature of technology adoption is also an essential element in adaptive research, as shown here in a case study of US agriculture in California, where the social, economic, and agricultural environments are relatively homogeneous, and where the limits of farm resources are far less severe than in less developed regions. Selective technology adoption is positive because it allows farmers to use a general technology after adjusting it to their specific conditions (Horton 1986). Specific goals of induced innovation may, however, not be fully attained if the technology is only partially or selectively adopted. This situation is illustrated by the diffusion of an innovation in pest control known as Integrated Pest Management (IPM), an innovation developed in order to reduce the V O L . 5 1 , NO. 4 W I N T E R 1 9 9 2


amount of chemical pesticides that farmers use. Our research suggests that achieving IPM's general goal may be hampered, since many of the behavioral components of IPM technology have been partially adopted. This research confirms the important contributions that anthropological research can make to the design and implementation of IPM programs (Bentley and Andrews 1991; Goodell, Andrews, and Lopez 1990). It adds to this previous work by detailing exactly how farmers selectively adopt and adapt IPM technology. Despite an intensified focus on understanding of farmer decision-making processes regarding, publicly funded research and extension cannot generate agricultural technologies that are suitable to all circumstances; farmers will always carry out the final stage of testing the innovation themselves (Brammer 1980). The incidence of farmers' selective adoption of technologies can be reduced, but it will not disappear as a result of adaptive research. Most evaluations of technology adoption, however, continue to use a dichotomous measure of adoption, and frequently those farmers who have selectively adopted particular components of a technology, or who have modified the technology to suit their needs are considered non-adopters. The tendency to perceive adoption as dichotomous is perpetuated by the complexity of studying selective adoption, by limited agricultural research budgets, and by a mind-set that views agricultural change as a linear process whereby local variation is eliminated by adjustment to forces such as technology and prices. The view that technology adoption is dichotomous also reflects an emphasis on the hardware of technology. This emphasis is not suitable for many technologies, especially those like IPM that involve complex behavioral changes and new perceptions rather than new hardware. The message that adoption is only partial can be unwelcome to agricultural scientists and extension agents because it makes their work more difficult. The limited number of studies that have investigated the degree of selective adoption highlight the importance of expanding the definition of adoption to include partial adoption and modification of technologies (Franzel 1984, Gerhart 1975, Gladwin 1976, Ryan and Subrahmanyam 1975, Winkelmann 1976). The failure to recognize the importance of selective adoption frequently results in misrepresentation of farmers' willingness or ability to adopt innovations in addition to inaccurate assessments of the impact of technology adoption (Merrill-Sands 1986). In order to evaluate the degree to which farmers are adopting agricultural innovations, researchers must recognize that partial adoption is not equivalent to non-adoption, and that modification or adaptation of technologies is not improper but a natural part of the innovation process (Rice and Rogers 1980). Understanding partial adoption is also necessary to achieve the original goals of induced innovation, which lie outside of adoption per se. This paper describes the adoption of Integrated Pest Management practices among pear growers in two California counties in order to illustrate the degree to which farmers are selective in their adoption and use of recommended technologies. This selective adoption behavior is explained by the differences in the characteristics of individual farmers and farming operations.

use of synthetic organic pesticides has been the dominant method of control for pests of all types (including insects, pathogens, and weeds). California farmers have become accustomed to applying pesticides on a set schedule in order to prevent the buildup of pests that could be damaging to their crops. The adverse effects of this heavy reliance on synthetic chemicals have appeared with increasing frequency. Pests that were formerly controlled by natural enemies have begun to cause significant crop damage, and many pests demonstrate resistance to previously effective chemical applications (Zalom and Flint 1990). In addition, growing public concern over the effects of pesticide use on the environment, the health of farm workers, and food safety is leading to increasingly stringent government regulation of pesticide use and registration. As a result, university researchers and growers are searching for alternatives to the current reliance on chemical methods of pest control. Integrated Pest Management is frequently cited as a viable alternative to conventional pest management programs that rely heavily on scheduled applications of pesticides (Flint 1989). Integrated Pest Management programs aim to reduce the pesticide load in the environment by increasing the predictability and effectiveness of pest control techniques and increasing the utilization of natural pest controls. The University of California Cooperative Extension has been conducting research and promoting IPM since the early 1970s. Pears were the first crop to have a formal set of IPM guidelines. IPM differs from conventional pest management programs in that it is a management intensive technology, requiring a dynamic decision-making process on the part of the grower. Rather than relying on predetermined prophylactic chemical applications with the goal of pest eradication, IPM emphasizes the importance of non-chemical preventive measures and the use of pesticides only when necessary based on economic threshold levels. Active management on the part of the growers is required; they must continually gather and evaluate information about pest, crop, and weather conditions. In addition, the use of IPM practices frequently requires a greater reliance on Pest control Advisors and university researchers. IPM programs have been established in various California crops for more than ten years. Although there is a growing body of research on IPM both in the United States and internationally (Antle and Park 1989; Bottrell 1987; Corbet 1981; Goodell 1984; Grieshop, Zalom, and Miyao 1988; Hall 1977; Kovach and Tette 1988; Wearing 1988; Whalon and Croft 1984), there is great variation in the findings of the research in terms of the degree to which IPM has been adopted, which factors influence the level of adoption, and the consequences of adoption. The results presented in this paper demonstrate that growers do not adopt IPM as a package technology; rather, they selectively adopt particular components of the technology that best suit their individual needs. The results also show that characteristics of the farm manager and the farming operation influence the decision about which components to adopt.

California Pear Production California Pest Management Pest management in California agriculture is in a period of transition (Lyons and Zalom 1990). Since the early 1940s, the



Orchard crops rank high in both their value and acreage in California agriculture. California ranks first in its share of US pear production (CDFA 1986). Pears are produced in 28 counties in California, covering 9,700 hectares in total. Fifty percent of

the bearing acreage is planted in Sacramento and Lake counties, and is divided among approximately 100 farmers (see Research Methods, below). The economic conditions of the pear production industry have been steadily declining over the past 15-20 years as a result of increased production, decreased demand, and rising production costs (O'Rourke 1982). The market demand for extremely high quality fruit, and the frequency and severity of pest and disease problem in pears have resulted in growers allocating nearly 25% of their total production costs for the control and prevention of insects, rodents, weeds, and disease in the orchards (Vogel, Klonsky, and DuBruille 1987). The pear crop is plagued by many insects and diseases, and we will focus on three of the most important ones. Codling moth (Cydiapomonella) is the major pest problem of the pear industry. This moth's larvae are a constant threat to pear orchards, capable of causing serious reduction in yields and in the market value of the crop. Growers control codling moths with pesticides, but they have proven to be a very resilient and persistent pest; as a result, frequency and rates of applications are always being increased in order to maintain control. Codling moth is a major target of both conventional spraying and IPM. Pear psylla (Psylla pyricola) and mites (e.g., pear rust mites, Epitrimeruspyri) are secondary pests, but both their populations and the extent of damage they cause are increasing. Pear psylla secrete honeydew, which blackens the fruit, and heavy infestations can cause partial defoliation. In addition, the pear psylla is associated with the spread of pear decline disease. Pear psylla are conventionally controlled by a combination of dormant oil and pyrethrum applications. several species of orchard mites can also cause serious defoliation of the trees, and they are conventionally controlled by dormant oil and one or more rniticide applications. The objective of IPM has been to reduce the amount of pesticides used to control these three pests by assisting growers to move from a scheduled to an "as-needednapplication of sprays, by recommending more pest-specific chemicals, and by using beneficial organisms to help control the buildup of pest populations. Adoption of IPM has been shown to reduce pesticide use in other tree crops (Kovach and Tette 1988). Our grower informants indicate that IPM has been very useful in helping them to manage pests, but that pesticides remain an important element in their control programs. Besides the grower, three different types of technical advisors are involved in the pest management of pears in California; farm advisors of the University of California Cooperative Extension, and certified pest control advisors (PCAs) who were either independent advisors or employees of chemical sales companies. The two types of PCA differ in that the latter represent outlets of companies that produce or market pesticides. Pest management strategies at the farm level fall along a continuum between two poles. At one pole a grower manages pests by using prescheduled pesticide applications. Because it is not sensitive to actual levels of pest infestation in the orchard, this type of management is conducive to heavy pesticide use. At the other pole, a grower uses the minimum amount of pesticide that is needed, based upon careful monitoring, use of beneficial organisms to combat pests, and economic evaluation. It is not obligatory for chemical company PCAs to recommend scheduled sprays and to eschew IPM, or for independent PCAs to do the opposite. Results of this study, however, indicate that there is a tendency for independent PCAs to emphasize IPM more heavily and for chemical company PCAs to rely on scheduled sprays.

Components of Pear IPM Program The University of California Cooperative Extension and Animal Plant Health Inspection Service of the USDA provided funds in 1973 to initiate an integrated pest management program for pears in California (Barnett, Davis, and Rowe 1976). The promotion and implementation phase of the project lasted from 1973-1976 with the number of growers participating varying from 66 to 87. In 1978 the University of California published Pear Pest Management (DAS 1978), a set of guidelines that incorporated much of the information that had been gathered about IPM for pears since 1971. The IPM program for Bartlett pears in ~aliforniaconsists of several components (see Table 1) that are meant to be used in combination with each other in order to gain the best possible control of pests in the orchard with the least disruption to the natural ecological system. Each of the components and the behavior required of the grower to implement them are described below,

PEST IDENTIFICATION. The IPM program emphasizes the need to know what the cause of the problem is, and to distinguish between pest problems and nutrient or soil deficiency problems. The program provides photographs, descriptions, and figures to assist in accurate pest identification.

PEST MONITORING.The IPM program provides specific schedules for monitoring different pest species throughout the year, indicating the most effective frequency and type of monitoring, based on the phenology of the pest and the trees' stage of development. Monitoring ranges from visual checks in the orchard, counting insects on leaves, and the use of pheromone traps.

USE O F BENEFICIALS.The pear IPM program emphasizes the importance of beneficial organisms as a means of natural pest control. The guidelines recommend taking regular population counts of the predators and parasites of the major insect pests. If beneficial populations are high enough, pest applications can be reduced or eliminated. These regular counts also serve as indicators of the degree to which chemical applications are reducing populations of beneficial organisms. WEATHER MONITORING.The IPM program provides detailed information on the best ways to monitor weather conditions, suggesting that growers obtain regular weather data from their own orchards rather than relying on less accurate radio and newspaper reports, which only give area-wide information. The calculation of accumulated degree days is recommended to forecast the development of codling moth populations.

CONTROL ACTIONGUIDELINES.This is a pivotal component of the IPM program. Control action guidelines, commonly

TABLE1. Components of IPM Adoption Pest identification Pest monitoring Use of beneficial organisms Weather monitoring Control action guidelines Management methods

V O L . 51, NO. 4 WINTER 1 9 9 2


referred to as economic threshold levels, indicate when a grower should take management actions to avoid economic crop losses. The use of control action guidelines is contingent on consistent and accurate monitoring of pests, weather, and other orchard conditions. The concept of economic thresholds requires that the grower allow pest populations to remain in the orchard at low levels, and apply chemicals or take other control measures only when pest populations reach levels that will cause economic damage to the crop. Many pest control guidelines have not been precisely established, and the grower must make use of all available information including extent of pest infestation, history of pest cycles in the orchard, the orchard's stage of development, and weather.

MANAGEMENT METHODS. One of the most important components of IPM is the use of management methods or cultural controls that prevent or reduce the possibility of pest outbreaks. These management methods include: selection of the proper site for planting an orchard; choosing cultivators and rootstocks that have some resistance to pests or disease; proper irrigation and pruning; good sanitation in the orchard; and the selection of pesticides that are least disruptive to the natural enemies in the orchard. Research Methods The IPM program is designed so that the combined use of all of the components will result in optimal pest control with the least use of harmful chemicals. It is possible, however, for growers to adopt certain components and not others, or to use the practices of one component differently from the optimal recommendation, as illustrated by the deceptively simple monitoring component. IPM recommends monitoring throughout the year for control of the three leading pests of pears (codling moth, mites, and pear psylla). Monitoring for codling moth occurs during five different periods of the yearly cycle (dormancy, budpetal fall, petal fall-fruit set, fruit set-harvest, and harvest-leaf fall); it should be accomplished by using four complementary methods (visual, leaf samples, traps, and fruit samples). Different monitoring techniques are used for both pear psylla and mites. The potential for large and continuous variability in monitoring means that the use of dichotomous behavioral measures (e.g., monitors/does not monitor) is virtually meaningless. Growers may adopt pest monitoring but not the economic threshold or the monitoring for beneficials components that are also designed to reduce the number or rate of chemical applications. A possible result of partial adoption is that the hoped for reduction in pesticide use from IPM adoption is not achieved. Partial adoption makes the data on IPM use difficult to gather and to analyze. Many farmers studied identify themselves as IPM users, even though their actual pest management methods are quite varied. Factor analysis was used in this study to create a scale of adoption, which measures the degree to which pear growers in Lake and Sacramento counties use four of the six components (pest monitoring, monitoring of beneficials, weather monitoring, and economic thresholds). The pest monitoring component was studied by looking separately at the monitoring of each pest. Data on each of the four key components of the IPM recommendations were gathered in a lengthy interview. These data were assembled by factor analysis into a scale that reflects



the extent to which growers were using the combined pest management practices that make up the IPM program. A high score (5) reflects close approximation of the ideal IPM recommendation. Factor analysis allows for the reduction of a large number of variables into a smaller number of factors (Kim and Mueller 1978). This reduction is necessary in the larger analysis of why growers use IPM differently. There are approximately 112 commercial growers who produce pears in Lake and Sacramento counties. A survey was designed in consultation with University of California IPM specialists, Farm Advisors, and independent pest control advisors (PCAs) with active businesses in advising pear producers in the two counties. Interviews were also conducted with all of the pest control advisors for pears in the two counties: two independent PCAs and five chemical company PCAs. We contacted 99 of the commercial pear growers from the two counties to inquire whether they were interested in participating in the study. Eightyone growers agreed to participate, but we were only able to schedule interviews with 64 (57 % of the total number of growers), and the information in this study was gathered from in-person interviews with these growers. Twenty-two growers from Sacramento County and 42 from Lake County were interviewed. The interviews took between one and two hours each and were usually conducted in the homes or businesses of the growers. Lake and Sacramento counties were chosen because they are the most important pear producing counties in California and because they represent different agricultural systems. Table 2 shows some of the similarities and differences between the pear farming systems of Sacramento and Lake counties. Sacramento County pear production is located in the Delta region, just south of the state's capital. It is characterized by larger farms and a generally higher capitalization in agriculture than Lake County. Lake County is in the cooler, hilly region of the California coast range, northeast of the San Francisco Bay region and northwest of the Sacramento Valley. The pear production of Sacramento County is primarily destined for processing into canned pears, fruit cocktail, and juice. Although Sacramento farmers tend to have larger farm size than Lake County farmers, none of these farms is representative of the monolithic corporate agribusiness operations that frequently characterize California farming. Most individual growers have fewer than 150 acres in pears and fewer than 300 acres in total. Many of the orchards were planted well over 100 years ago and have been farmed by the same families for more than two generations, sometimes as many as five or six. The growers surveyed were predominantly European Americans, but Sacramento has a small percentage of Asian growers, and Lake County has some Hispanic growers. The farmers in the sample had a fairly high level of formal education; only 2% of the respondents had less than a high school education, and 42% of the total sample had a college degree.

Partial Adoption of IPM Components Each of the four components was measured on a standardized scale of 1-5, with 5 representing the highest level of adoption. Table 3 summarizes the standardized mean scores, standard deviation, and coefficients of variance for each component. This table shows that codling moth monitoring and the use of economic thresholds have been nearly fully adopted by a majority

TABLE2. Characteristics of Pear Growers in Sacramento and Lake Counties ( n = 64) Sacramento county

Lake county

Ethnic background (%) European Asian Hispanic

97.6 0 2.4

Gender (%) Male Female

90.4 9.5

Mean age of grower


Education (%) High school degree only College degree

19.0 38.0

Farm structure Total farm size (mean, ha) Area in pears (mean, ha) Average number of crops % with farm manager % income from farm % business type farm operations

50.6 35.6 1.9 16.7 69.7 42.9

Self-identify as IPM user (%)


Pear production Fresh market (%) Yield (1987-1989) (met. tlha)

50.6 5.87

of the growers while the monitoring of beneficials and the use of weather monitoring show very low levels of adoption. Previous research has suggested that in the process of selective adoption, people are more likely to adopt innovations that are compatible with their current situation (Rogers 1983).Codling moth monitoring and economic threshold components of the IPM program, both aimed at more efficient use of pesticides, have been more readily adopted than the components that focus greater reliance on alternative or natural methods of pest control. The use of chemical pesticides has been an established part of pear production for 50 years. Growers are accustomed to using pesticides as a normal part of their pest management routine, and so the transition to using these pesticides more efficiently does not require major changes in this routine. Some are reluctant to rely on beneficial organisms as a means of control because of the perceived incompatibility of this practice with conventional

chemical pest management programs. Reliance on beneficials also entails more complex and time consuming management decisions that make it incompatible with current management strategies. Unequal adoption of the three monitoring components is also explained by the novelty of some methods and not others, by the history of infestations of different pests, and by the complexity of some methods. Pear industry quality and cosmetic standards are so high that any failure to control codling moth damage translates directly into crop losses. As a result, methods for monitoring of codling moth have steadily improved over the years, and the current use of pheromone trapping is well tested and quite effective. Because growers have been using some sort of trapping and monitoring method to gage codling moth populations for many years, the current monitoring methods may be considered an improvement of an old practice rather than a new practice to be adopted. The long-term use of monitoring has also reduced uncertainty about the practice, and growers have learned that IPM codling moth monitoring helps insure high quality fruit. The development of methods to monitor mites and pear psylla are a more recent phenomenon. Damage as a result of these pests is more indirect and has only become a major problem as a result of chemical applications to control codling moth. Monitoring for these two pests tends to be more time consuming and less precise, possibly resulting in the lower adoption rates by farmers. Complexity as a factor in adoption is also evident in the great variability in adopting the weather monitoring component. The farmers' perception is that calculating accumulated degree-days is overly complex. Consequently, most rely on areawide weather monitoring rather than taking actual temperature readings in their own orchards, a more accurate measure when using the degree-day system

Characteristics of Farms and Farmers that Influence IPM Adoption The variability in level of IPM adoption is particularly interesting because of the type of farming system that was studied and the fact that the innovation has been widely diffused throughout the two farming communities for over ten years. While there was variability among the total sample of growers studied, these growers are alike in important ways. They participate in the same commodity system, and their pest management is under similar economic and regulatory pressures. They operate in an atmosphere that is heavily charged with information and con-

TABLE3. Summary of Statistics for Grower Scores on Individual Factors Factors

Standardized mean* Standard deviation Coeff. of var. % scores > mean

* Standardized

I monitor psylla

I1 monitor codling moth.

4.0 892

4.8 692

21.9 55

14.5 85

Ill monitor beneficials 1.4 2.649 192.7 37


IV monitor mites

weather monitoring

VI economic threshold

3.8 775

3.3 989

4.7 733

20.2 64

29.9 57

scale of 0-5. V O L . 51. N O . 4 W I N T E R 1992

15.7 75

cern about pesticides. All of the growers use pesticides that require them to file use reports with the California Department of Food and Agriculture. The pear growers of this study all live and interact in the same communities, and many of them have family ties with each other, or have had the same neighbors throughout their lifetimes. Their children go to the same schools, and it is not surprising to find several pear growers sharing a morning cup of coffee or gathering in front of one of their barns. Despite close ties and natural sharing of information and ideas that goes on between these farmers, they have chosen to make different decisions about the adoption of IPM as an agricultural technology. The process of technology modification, or selective adoption, is the means by which growers fit the technology to their local situation, taking into consideration economic, physical, and social resources and constraints as well as the goals of the farming operation. The transformation of agricultural systems involves a changing balance between the major factors of production (land, labor, and capital) so that a change in one factor, such as the influx of capital, can alter the relations of production and thereby change the structure of agriculture. Social scientists have shown how these three factors of production shape the creation and diffusion of new technology. IPM is an interesting case because its genesis did not derive directly from a change in the relations of production, but rather from political pressure from biological scientists and the public to reduce the amount of pesticides. The diffusion of this technology is possibly explained by the different balance of land, labor, and capital on each farm, but the complexity of California agriculture makes it untenable to study these factors in any simple or direct way. Multiple regression models comparing farm size, household labor, and income to pear IPM adoption were consistently insignificant. In our sample, farm size, location, and marketing strategy are highly correlated because of the differences between the two counties (Table 2). We chose marketing strategy as a representative variable because it reflects a behavioral choice as well as locational and structural characteristics. We chose to examine five variables that reflect differences in land, labor, and capital. There is no one-to-one correspondence

between any of these variables and the major factors of production. Rather, each variable reflects the interaction of the major factors of production. In an effort to model the relationship between IPM adoption and the nature of farming systems, five characteristics were chosen as independent variables: education, Cooperative Extension influence, marketing strategies, farm type, and farm diversity. They were chosen because of the extensive social science literatureon the diffusion of agricultural technology, and our ethnographic knowledge of pear production in California. In order to test the importance of different social characteristics and management styles on the adoption of individual components of IPM and on the overall use of this technology, we ran separate multiple regressions on adoption of each of the four individual IPM components as the dependent variable. Finally, we ran the combined scores of these four components (scale of adoption) as a dependent variable in the same model. In testing the individual components, only two of the five equations (those for economic threshold and monitoring beneficials) were significant at the .05 level of confidence. The equation for the combined scores (scale) was significant at the .0001 significancelevel. These five characteristics and their influence on selective adoption decisions are described below; Table 4 summarizes the relationships.

EDUCATION.Previous research has shown that higher levels of education generally lead to higher levels of adoption of agricultural technologies (Feder, Just, and Zilberman 1985; Rogers 1983), and our study corroborates this finding for IPM adoption as well. Education is not significantly correlated with farm size or income. Those growers with more years of formal education showed higher levels of adoption for each of the components of the IPM program. The significance of this variable can be explained by the fact that the growers with higher levels of formal education had access to a wider array of information sources as a result of their contacts beyond the farming community. Level of formal education has implications for the source of information and its value to the grower. Growers with more education had more regular contact with university researchers and were more receptive to university-generated technologies. In con-

TABLE4. Characteristics of Farmers and Farm Operations and Their Relationship to IPM Adoption Dependent variables (standardized regression coefficients)

Independent variables Education Cooperative extension influence Fresh market strategy Family farm type Farm diversity

Overall adoption adjusted r2 = A l l p = .0001 (n = 54) .294** 245* 477*** 283* 1.677


Economic threshold adjusted r2 = ,212 p = .0038 (n = 57) 222** 055 203 - .265* 1.675*

Monitoring beneficials adjusted r2 = ,277 p = .006 (n = 56) .202** 135 484*** .334** 1.676

trast, growers with less formal education were more likely to be skeptical of research emerging from the university and place a higher value on information gained through personal experience.

COOPERATIVE EXTENSION INFLUENCE.Cooperative Extension influence is another element in the context in which the growers process information. This variable was tested against education, farm size, and income, and no significant correlations exist. Growers who place a high value on information obtained from the Cooperative Extension advisors are more likely to adopt IPM than are those who place a higher value on other information sources. The frequency of contact with agricultural extension agents (a variable that showed no significant relationship to adoption of IPM) is less important in explaining adoption behavior than the context in which growers process agricultural extension information. Cooperative Extension influence does not refer solely to the specific time frame of the study (1988-89), but also includes the influence of Cooperative Extension over the past ten to 20 years. Direct contact between growers and University Cooperative Extension Service used to be more frequent, and it was important in shaping long-term attitudes about pest management decisions. The percentage of the farm's total MARKETING STRATEGY. pear crop being sold for fresh market consumption or for processing is a variable that reflects the farmer's marketing strategy. Because of the difference in marketing strategy in Lake and Sacramento counties (see Table 2), this variable is clearly related to location and farm size, and so we did not use either location or farm size in our multiple regression model. Market strategy was chosen because it reflects both of these other factors, as well as a behavioral aspect of production. A majority of growers indicated that they tried to sell some portion of their crop on the fresh market because doing so gave them a higher return, but the farmers' marketing strategies were largely dictated by location, timing of the harvest, and available outlets for the crop. Because quality standards are higher for fresh market sales, the percentage of the crop being sold to the fresh market has a direct influence on pest management decision-making. The quality standards for fresh market pears are high, and fresh market growers cannot afford to risk any insect damage to their fruit; however, these growers showed higher levels of IPM adoption, particularly for the beneficials component. Fresh market producers use the pest monitoring components of IPM to insure higher quality fruit to detect problems that might otherwise have gone unnoticed. Some growers indicated that the use of monitoring techniques occasionally led to more chemical applications to solve these problems. Some growers also indicated that they were using IPM practices because they helped meet the consumer demand for reduced pesticides. Consumers' conflicting demands for "pesticide-free" but cosmetically perfect foods present fresh market growers with the difficult task of producing a crop that is of extremely high quality with the use of very few pesticides. Greater reliance on beneficials among growers who emphasize fresh marketing was seen as a step toward producing fruit that would be more acceptable to consumers. Table 5 shows that growers who chose to hire an independent PCA had significantly higher percentages of their crop being sold to the fresh market. Independent PCAs have the time to devote to developing an intimate knowledge of their client's orchards on a weekly basis, and they also tend to work more closely

with the growers in making pest management decisions. The incorporation of beneficial organisms into a pest management program requires this kind of in-depth knowledge of the orchard and the pest interactions. In addition, those growers who use the services of a chemical company PCA may receive less assistance in incorporating beneficials into their pest management programs because these PCAs have less incentive to recommend alternativesto pesticides since their primary job is chemical sales.

FARM TYPE. The type of farm has been widely studied and shown to influence farm management. Critical factors have been farm size and whether or not it is a family farm. Here we look at the latter factor. Each of the growers in this study was classified as having a family-oriented farming operation, or a businessoriented operation. Table 6 shows the criteria used to classify farmers into these categories. In addition to these variables, the classifications were verified by ethnographic research that included visits to the farm and discussions with Cooperative Extension Specialists familiar with the different farms in their regions. The criteria are based on elements commonly used to define family farms (Brewster 1979, Reinhardt and Barlett 1989, Tweeten 1984). Farm size is clearly a factor here, but this study does not use farm size or annual sales as criteria to differentiate between family- and business-oriented farms, because of the locational difference noted above. Since many of the larger farms fit all the other criteria for a family-oriented operation, and some smaller farms were strictly market-oriented operations, we believe that the proposed criteria provide a more accurate distinction between the differences in management approaches and goals of the two farm types as suggested by Reinhardt and Barlett (1989). The farm type variable is representative of the way in which social structure characteristics can influence farming strategy by shaping grower attitudes and information transfer. The significance of the farm type variable in explaining levels of adoption is consistent with other studies that have compared ethnic groups that have different farming strategies (Salamon 1985, McQuillan 1990). There are a number of reasons why a family farming strategy could lead to higher levels of IPM adoption. The tendency among family farmers to have more extensive interpersonal communication networks has been demonstrated in previous research (Goldschmidt 1978, Poole 1981) and was also found in this study. Families who had lived and farmed in the same area for several generations have dense social relationships established through farming connections and social events. These growers are acutely aware of what their neighbors are doing, how frequently they spray their orchards, and what sort of crop they harvest each year. While there was no significant difference in the average number of agricultural organizations

TABLE5. Relation of Average Percent of Crop Sold to Fresh Market to Type of PCA* No. of growers

Average % fresh market


43 15

41.46 48.47




Type of PCA Chemical company NO

* Significant at

the .04 level based on a one-tailed 1-test.

1" No data on fresh market % from one grower in this category. VOL. 5 1 . NO. 4 W I N T E R 1992


TABLE6. Criteria Used to Differentiate Family- vs. Business-Oriented Farms Family farm 1. 2. 3. 4. 5.

Three o r more generations farming Family contributes labor to operation Family residence is on property Own land o r manage for family member Majority of family income earned from farm

that family farmers or business farmers belonged to, family farmers were significantly more active in the organizations. These strong communication networks lead to a more frequent sharing of opinions and information among family farmers, and much of this information is based on personal experiences. A group of pear farmers in Lake County meet informally every morning at a local cafe. Growers with relatives farming in the area spoke of their shared philosophies and information exchange. The longevity of acquaintance, depth of knowledge, and mutual respect among family farmers increase the probability that these growers would influence each other in their decision-making processes. Family farmers share communication networks that business type farmers do not, and this has implications for both the type of information that is received and the context in which it is received. Other factors that distinguish the family farm strategy from the business farm strategy influence the context in which growers consider information about IPM. The interviews with growers provided support for previous research findings that family farmers tend to have a stronger emotional attachment to the land that has been passed on through generations and that the growers have the intention of keeping in the family for generations to come (Coughenour and Tweeten 1986, Marans and Dillman 1980, Rosenblatt 1990). Several growers had quit their jobs and moved back home to run the family farm after the death of a parent. Many growers talked with pride of how long their family had farmed on the land and were hopeful that their children would express an interest in farming. Several growers were well beyond retirement age, but continued to be actively involved in the farming operation because "it was their life." A family homestead is often located on the farm property, and the farm land is considered a part of the family's lifestyle. Sonya Salamon notes that "farm families choose among alternatives on the basis of overarching goals" (Salamon 1985), suggesting that short-term profit motives are not the only consideration when making farm management decisions. The stronger and more complex ties to the land of family farms are a partial explanation of the higher levels of IPM adoption among this group. IPM is sometimes promoted as an environmentally beneficial technology whose long-term benefits may be greater than the short-term benefits, and this aspect of the technology appeals especially to family farmers. Family farmers are particularly more likely to adopt the beneficial~component of the IPM program. In order to incorporate the use of beneficial organisms into a pest management program, a delicate balance between population levels of pests and beneficial~must be maintained in the orchard. Doing so requires the grower to have an up-to-date and intimate knowledge of his or her orchards, a quality typical of family farmers resulting



Business farm 1. 2. 3. 4. 5.

Two o r fewer generations farming Primarily hired labor Family residence separatelin town Combination of owned and leased land More diversified sources of family income

from their long connection with their land. It also requires more intensive management decisions about if and when chemical applications are necessary, and about what types of material and application rates will be least disruptive to the beneficials. Family farmers are usually willing to put in the additional time that this more intensive management system requires. Business farmers, who have more diversified income sources, may not be willing to invest additional time in pest management, when the application of a pesticide can meet economic goals. Business farmers view the land more as an economic investment, and they may not hesitate to sell the land if doing so is more profitable than continuing the farming operation. Growers with a business strategy are more likely to live in an area separate from the farming operation, and to have additional employment outside the farm. Family farmers are more likely to own their land, while business farmers are more likely to lease some portion of their land. The negative correlation between family type farms and the adoption of the economic threshold reflects the tendency of these farmers to embrace IPM as a means to better stewardship of their land. Family farmers who use other IPM components to a greater extent than economic thresholds explain that their pest management is conditioned only in part by economic calculation. The greater use of economic thresholds by business-type farms allows the grower to continue using pesticides as a primary means of pest control; however, it is designed to result in better control and fewer pesticide applications by improving the timing of applications.

FARM DIVERSITY.In this study, farm diversity was measured by the ratio of pear acreage to total farm acreage as an indication of importance of pears to the total farm operation. Previous research has suggested that improved pest management practices are less compatible with diversified farms (Norgaard 1976), and this finding proved to be true in our study. Because IPM is a very crop-specific and management-intensive technology, it is not surprising that it is more compatible with the management approach for farms that have the majority of acreage devoted to pear production. Farm diversity is particularly influential in the decision to adopt the economic threshold component of the pear IPM program. When the majority of acreage in a farming operation is planted to one crop, the majority of management, labor, and equipment time is devoted to that crop, allowing for flexibility in scheduling pesticide applications. A diversified farming operation requires more advanced scheduling of equipment and labor. If economic thresholds indicate that spraying for codling moth must be done immediately, management, labor or equipment necessary to complete this task may be tied up in another way.

Case Studies Although most growers have adopted some component of the IPM program, there is variability both in the degree to which the components have been adopted and the reasons behind the adoption decisions. Some growers have embraced IPM both in concept and practice, while others remain very skeptical. Some growers turn to IPM practices for philosophical reasons, others for economic reasons, and still others use IPM practices without having made a conscious decision to do so. The case studies below illustrate the ways in which characteristics of the farms and farmers have influenced the selective adoption of IPM components.

F. Wu (Sacramento County).

F. Wu operates one of the largest pear orchards in California. A Chinese American, his father first began work as a tenant farmer in the early 1900s. Wu now operates F. Wu Diversified Farming, a 3,000 acre operation of primarily leased land. Wu owns 200 acres of pear orchards and leases 550 acres. He plants the rest of his land in tomatoes, corn, wheat, and safflower. Wu is over 70 years old, is a high school graduate, and runs his operation with the assistance of family members. Despite the family involvement, Wu's operation is unquestionably business-oriented. In conjunction with his sons, he runs a large trucking operation and nationwide nursery business in addition to the extensive farming operation. Wu has a large and steady outside labor force that carries out most of the work on the farm properties under the direction of the ranch foreman. Wu generally sells only 30% of his crop to the fresh market and uses the service of a local chemical company PCA to assist with his pest management. He first heard of IPM in the late 1970s; he is familiar with the program but feels that his own system of pest management works fine. Wu is reluctant to rely too heavily on outside information sources, and placed a strong emphasis on the quality and extent of his personal experience in farming. The only components of the IPM program that Wu has adopted are monitoring for codling moth and pear psylla. He does not, however, use the monitoring as an aid in scheduling pesticide applications, as he prefers to rely strictly on prescheduled applications. He said that the size and extent of his operation make it too difficult to spray in response to specific conditions. Monitoring helps him to identify emergencies and problems that his pre-scheduled sprays miss. Wu thinks that increasing environmental concern will eventually force him to change his chemical application practices and possibly lower his standards about what is acceptable quality fruit. Nevertheless, he is not willing to use natural control practices now for fear that he will lose his edge over other growers in terms of the quality of the crop and size of his yields. Wu says he will wait until the laws change.

W. RUTHERFORD (Lake County). W. Rutherford is a fulltime accountant who owns 60 acres of pears as a side business. He is in his late 40s; his wife also works, and he has three grown children who no longer live at home. The farm is incorporated and is run primarily by a foreman and two full-time agricultural laborers. The Rutherford family has been involved in growing pears for two generations, but is has never been their principal occupation or source of income. Although Rutherford considers

himself the overall manager of the farm, he does not live on the farm property and is not involved in the everyday activities of the farm. The local chemical company PCA advises him on pest management and seems to have a considerable degree of influence, Rutherford was unable to answer most questions about his pest management practices. Rutherford did not consider himself to be an IPM user; however, his responses and those of his PCA indicated that he was using both the monitoring and economic threshold components of the IPM program. His orchards were monitored regularly, although somewhat less frequently than other growers, and the combination of the monitoring and economic threshold levels were used as a guide to chemical applications schedules. Even though the farm was not the primary source of income for his family, Rutherford seemed interested in running it as a business and cutting costs as much as possible. The small size of his farm and the fact that pears are his only crop, allowed him the flexibility of spraying only when necessary based on the economic threshold levels as a means of cutting costs. Like Wu and many other growers, Rutherford felt that the incorporation of beneficial organisms into his pest management program would result in a lower quality crop, and he was not willing to take this risk. He felt that restrictions on pesticide use in California were already very strict, a condition he believes should be brought to the attention of the public. He felt that consumers' expectations about the quality of the food they buy must change in order for farmers to change their pest management practices. Rutherford sells 40% of his crop to the fresh market, which is considerably less than other growers in his area.

THESTEWARTS(Sacramento County). Adam and Robert Stewart, both in their mid-30s, run the family farming operation together. Their family has been growing pears for five generations, and the two brothers took over the operation from their father after they finished their college educations. Both are married with young children and work full time on the family farming operation. They have 400 acres planted in pears and 65 acres of cherries and kiwi fruits. The Stewarts heard about IPM in the mid-1970s through Cooperative Extension. They deepened their knowledge about IPM through their college courses and Extension-sponsoredIPM training sessions. They are well versed in the concepts and practices of IPM and have chosen to make most of their pest management decisions without the advice of an outside PCA. They place a high value on information gained through Cooperative Extension, and have regular contact with them. The Stewarts have adopted all of the IPM components to varying degrees. They have a monitoring program for weather, pests, and beneficial insects, all of which they do themselves. Although they monitor pests less frequently than some of the independent PCAs, they indicated that the reason they decided to use IPM practices and to do all of their own monitoring was so that they could have more control over what happened in their orchards. They felt that the use of IPM monitoring increased their awareness of the interactions occurring in their orchard, enabling them to produce a higher quality crop. The Stewarts sell 40% of their crop to the fresh market, a higher percentage than most of the other growers in their area. The Stewarts use the economic threshold components of the IPM program intermittently, sometimes relying on their own V O L . 5 1 , NO. 4 W I N T E R 1992


assessment of when the best time to spray might be. They place a heavy emphasis on incorporating beneficial organisms into their pest management program, keeping a close watch on levels of beneficial populations, and using chemicals that will not upset the balance between pests and predators. The Stewarts believe that the use of IPM practices is helping to reduce the amount of pesticides they are applying; their motivation for doing so is not because consumers demand it, but because it saves them money.

M . HAMILTON (Lake County). M. Hamilton quit her job teaching English literature at a junior college five years ago to take over the family farm after her father died. Her family has been growing pears for five generations, and she feels strongly about keeping the property under family management. She is in her mid-40s, holds a Masters Degree and is married to another pear grower in the area. Hamilton owns only 18 acres of pears herself, but manages 150 acres of the family property for her mother, who still lives on the farm. Hamilton showed very high levels of adoption for all of the IPM components. She hired an independent PCA based on the fact that he placed a heavy emphasis on IPM practices. She has adopted the beneficials component to a much higher level than most other growers because she feels that it helps meet the consumer demand for reduced chemicals. In addition, she describes herself as environmentally conscious, a philosophy shaped by her education, and she believes that the use of natural controls and other IPM practices is environmentally beneficial. Hamilton is very concerned with the long-term viability of the family farming operation, and thinks that the use of IPM practices is one way of ensuring that goal. The buildup of beneficial populations help to avoid surges in pest populations, and it also provides economic advantages by reducing the need for chemicals. Despite her high level of adoption, Hamilton notes some problems with the use of IPM practices. It has been necessary to accept more damage to her crop than she would like, but she believes this would be true anyway due to lack of adequate and acceptable chemical materials. She also reports that the use of IPM requires much more intensive management practices in the form of more labor supervision, constant vigilance, and frequent adjustments in the timing and type of control measures used. Because she has recognized these problems but still believes in the value of IPM, Hamilton works closely with Cooperative Extension experts and university researchers to promote alternative pest management programs.

Conclusions This study illustrates the extent to which farmers are selective and adaptive in their adoption of Integrated Pest Management practices despite the fact that the technology was promoted as a package to a relatively homogeneous population. The results demonstrate that farmers will adopt those components of the IPM program that are best suited to their circumstances and reject others or adopt them at a less intensive level. Different levels of adoption among farmers cannot be explained merely by lack of information or lack of economic resources. The significance of the five social variables tested in this study indicates that differences in farm management can help explain the variation in level of adoption. The five variables reflect the



priorities and goals of the farming operation, what is technically feasible for the operation, the source of pest management information, and the value the farmer puts on that information. Growers who have higher levels of education and who place a strong emphasis on Cooperative Extension information tend to have higher levels of adoption for all IPM components. Family farmers and those who sell a higher percentage of their crop on the fresh market are more likely to adopt the beneficials component, while business-oriented farms with less diversified operations are more likely to adopt the economic threshold component. The incidence of selective adoption, although interesting in and of itself, can have important consequences for the success or failure of agricultural technologies. Predictions of the consequences of technology adoption are often based on the assumption of full adoption. The failure of most evaluative studies to consider the degree of selective adoption may explain the inconsistent findings about whether technology diffusion and adoption is achieving its intended goals. This study of IPM adoption provides an excellent example of the ways in which selective adoption can influence the outcome of technology use. Recognizing that the primary goal of IPM is to reduce the pesticide load in the environment, some questions need to be asked in further studies: 1) is the adoption of all components of the technology necessary in order to achieve reductions in pesticide use?; 2) which components have the greatest impact on reduction in pesticide use?; 3) is it possible that the adoption of some components without the others can actually increase the level of pesticide use? In addition to providing insight into the consequences of IPM adoption, an analysis of selective adoption also provides important information about those components of the technology that are most in need of further research and promotion. The results of this study indicate that the codling moth monitoring component has been almost universally adopted, and that the beneficials component is most in need of improvement and promotion to the growers. Finally, this study informs us about the process of agricultural technology diffusion and adoption worldwide. The growers studied here have a higher level of education and greater economic resources than most of the world's farmers. They farm in a technologically advanced region, both in terms of agricultural inputs and communication systems. The pear IPM practices were developed for a particular micro-climate and were field tested in the orchards of farmers who participated in this study. The practices were evaluated both economically and agronomically and deemed to be beneficial on both counts. In spite of all of these seemingly positive elements of the diffusion process, our study illustrates a high degree of selective adoption. These findings call into question the common assumption that if farmers are involved in the research process, have adequate information and education, and are supplied with the appropriate inputs and economic resources, they will surely adopt technologies which have proven to be beneficial. This study indicates that modification and selective adoption of technologies are not merely characteristicsof the diffusion process among poor peasant farmers in less developed countries. Instead, it seems that adaptation occurs even under the best circumstances and should be considered a natural part of the adoption process. Recognizing the validity of selective adoption, rather than simply trying to overcome it, is the first step in answering some important questions about the nature of technology adoption.


All personal names used in these case studies are pseudonyms.

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