This article was downloaded by: [University of California Davis]On: 19 August 2015, At: 08:13Publisher: RoutledgeInforma Ltd Registered in England and Wales Registered Number: 1072954 Registeredoffice: 5 Howick Place, London, SW1P 1WG

Click for updates

Environmental Education ResearchPublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/ceer20

How pre-service teachers navigatetrade-offs of food systems acrosstime scales: a lens for exploringunderstandings of sustainabilityLina Yamashitaa, Kathryn Hayesb & Cary J. Trexlerac

a School of Education, University of California, Davis, CA, USAb Institute for STEM Education, California State University, EastBay, CA, USAc College of Agricultural and Environmental Sciences, University ofCalifornia, Davis, CA, USAPublished online: 19 Aug 2015.

To cite this article: Lina Yamashita, Kathryn Hayes & Cary J. Trexler (2015): How pre-serviceteachers navigate trade-offs of food systems across time scales: a lens for exploring understandingsof sustainability, Environmental Education Research, DOI: 10.1080/13504622.2015.1074662

To link to this article: http://dx.doi.org/10.1080/13504622.2015.1074662

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the“Content”) contained in the publications on our platform. However, Taylor & Francis,our agents, and our licensors make no representations or warranties whatsoever as tothe accuracy, completeness, or suitability for any purpose of the Content. Any opinionsand views expressed in this publication are the opinions and views of the authors,and are not the views of or endorsed by Taylor & Francis. The accuracy of the Contentshould not be relied upon and should be independently verified with primary sourcesof information. Taylor and Francis shall not be liable for any losses, actions, claims,proceedings, demands, costs, expenses, damages, and other liabilities whatsoever orhowsoever caused arising directly or indirectly in connection with, in relation to or arisingout of the use of the Content.

This article may be used for research, teaching, and private study purposes. Anysubstantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &

Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

How pre-service teachers navigate trade-offs of food systemsacross time scales: a lens for exploring understandings ofsustainability

Lina Yamashitaa* , Kathryn Hayesb and Cary J. Trexlera,c

aSchool of Education, University of California, Davis, CA, USA; bInstitute for STEMEducation, California State University, East Bay, CA, USA; cCollege of Agricultural andEnvironmental Sciences, University of California, Davis, CA, USA

(Received 27 November 2014; accepted 13 July 2015)

In response to the increasing recognition of the need for sustainable food sys-tems, research on students’ and educators’ knowledge of food systems and sus-tainability more broadly has grown but has generally focused on what people‘fail’ to understand. Moving away from this deficit approach, the present studyused semi-structured interviews to explore how 12 pre-service teachers (PSTs) inthe US consider sustainability in terms of the trade-offs – or concurrent costsand benefits – associated with using different agricultural resources over short,medium, and long terms. Drawing upon the constructs of framing, metacogni-tion, and complex causality, the study found that the majority of PSTs referred toindirect experiences of seeing or hearing about agricultural resources to demon-strate stable knowledge of short-term trade-offs and construct tentative knowl-edge about medium-term trade-offs. Few described long-term trade-offs. Mostparticipants also acknowledged some gaps in their knowledge in discussingtrade-offs across the different time scales. Findings suggest the importance ofleveraging and building upon educators’ (and ultimately students’) prior experi-ences to build their understanding of complex trade-offs that underlie foodsystems. The study also illustrates the value of using the concept of trade-offsacross time scales to explore people’s conceptions and understandings ofsustainability.

Keywords: food systems; sustainability; pre-service teachers; trade-offs; timescales; semi-structured interviews

Introduction

Wendell Berry, an American author and farmer, argued that eating is an agriculturalact and that ‘how we eat determines, to a considerable extent, how the world isused’ (1990, 149). Such agricultural use of the world’s resources has come withtrade-offs for society and the environment. For example, the use of fossil fuels infarm machinery and equipment has helped increase crop yields (Dimitri, Effland,and Conklin 2005) allowing for more efficient planting and harvest. These benefits,however, have come with long-term environmental costs, including contributing toclimate change through the use of fossil fuels (Eshel and Martin 2006; Lin et al.2011; Smith et al. 2007), soil compaction (Chyba et al. 2014), and poor soil quality

*Corresponding author. Email: lyamashita@ucdavis.edu

© 2015 Taylor & Francis

Environmental Education Research, 2015http://dx.doi.org/10.1080/13504622.2015.1074662

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

(Horrigan, Lawrence, and Walker 2002). The use of synthetic fertilizers andpesticides has also helped increase crop yields by solving the problem of infertilesoils and reducing damage by pests (Cooper and Dobson 2007; Paoletti, Gomiero,and Pimentel 2011), thereby lowering the costs of food. These economic benefitshave come at the expense, however, of environmental and social costs, includingsoil erosion (Gomiero, Pimentel, and Paoletti 2011), eutrophication due to fertilizerrunoff into water systems, loss of biodiversity (Tegtmeier and Duffy 2004), andhealth problems due to farmworkers’ exposure to pesticides (Arcury et al. 2010;Minkoff-Zern and Getz 2011).

In response to these types of trade-offs associated with the conventional foodsystem, numerous approaches toward socially and environmentally sustainable agri-culture and food systems1 have been developed in recent years. These range fromtechnology-based practices that use sensors in fields to tailor crop management prac-tices, to ecology-based practices such as agroecology, which aims to maximizeecosystem services through agriculture (Gomiero, Pimentel, and Paoletti 2011;Wezel et al. 2014). All of these approaches, however, also have different social,environmental, and/or economic trade-offs (Gomiero, Pimentel, and Paoletti 2011;Wezel et al. 2014). Technology-based practices, for example, may conserveresources and contribute to environmental sustainability but may not be economi-cally sustainable for some small-scale farmers. Therefore, what is consideredsustainable varies depending on context and place.

We argue that consumers, as participants in a democratic society, have a criticalrole to play in helping to decide and determine whether and how the use of particu-lar resources and/or farming methods is sustainable. In order for consumers to par-ticipate in such decision-making processes, it is important that citizens demonstratean ability to weigh and navigate the complex trade-offs that are associated with theirdaily decisions about what to eat. One logical place to foster such an ability is inschools, especially given education’s longstanding goal of fostering civic engage-ment (Dewey 1916) and practices of teaching a variety of subjects relevant to foodsystems, such as health and nutrition (CDC 2011). Preparing educators, especiallyand including pre-service teachers (PSTs), to think critically about trade-offs associ-ated with food systems, then, is an important step toward developing the capacity ofcitizens to engage in public discourse about sustainability. Moreover, the idea ofteaching about sustainability is slowly but steadily gaining traction in schools and inteacher education programs, both in the US and around the world (e.g. Belgeonneet al. 2014; Feinstein 2009; McKeown 2013; Mills and Tomas 2013). We argue thatresearch on PSTs’ knowledge of sustainability, as studied through the lens oftrade-offs associated with food systems, can offer important insights into howsustainability could be taught in teacher education programs.

Few studies, however, have explicitly used the concept of trade-offs – or the ideathat benefits or advances made in one area are associated with sacrifices in otherareas – as a lens for exploring educators’ understandings of issues salient to sustain-ability. Notable exceptions include the work of Trexler and colleagues that hasexamined PSTs’ (and students’) knowledge of social and environmental trade-offsassociated with agricultural resources such as pesticides (e.g. Trexler 2000; Trexlerand Heinze 2001; Trexler and Meischen 2002). We build on this work by seeking toexplore PSTs’ knowledge of short-, medium-, and long-term trade-offs of using agri-cultural resources, including pesticides, fertilizers, water, fossil fuels (as used intransportation, machinery, and synthetic fertilizers), soil, and farmworkers.2 We also

2 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

examined PSTs’ discussion of farming methods, specifically, organic andconventional farming. Furthermore, we argue that a nuanced analysis of thelanguage that PSTs use to discuss different trade-offs associated with the use of agri-cultural resources will offer insights about PSTs’ conceptions and understandings ofsustainability, thereby moving away from the tendency of previous studies tohighlight PSTs’ lack of knowledge.

Literature review

Given that there is currently little research on PSTs’ knowledge of sustainability asit relates to food systems, we discuss studies from related areas of research to posi-tion our study. We first review research that has explored PSTs’ knowledge of sus-tainability and then turn to studies that have examined students’ and PSTs’knowledge of food systems. Many of these studies, however, have tended to use adeficit lens to capture what participants ‘fail’ to understand. We therefore articulatethe need for more research that focuses on how participants demonstrate theirknowledge.

Knowledge of sustainability

Previous studies that have examined PSTs’ understandings of sustainability have pri-marily focused on their knowledge of various environmental issues, with particularattention to misconceptions about climate change, such as climate change beingcaused by ozone layer depletion (Bahar, Bağ, and Bozkurt 2008; Boon 2010;Papadimitriou 2004). These studies, however, fail to provide nuanced insights aboutwhat PSTs understand about other aspects of climate change, such as its social, envi-ronmental, and economic implications, or about the social and economic effects ofother environmental issues.

While one of the primary areas of research regarding PSTs’ knowledge of sus-tainability has been related to climate change, a small number of studies hasexplored PSTs’ knowledge of the social and economic aspects of issues related tosustainability. For example, studies have found that PSTs lack sufficient knowledgeof concepts such as intergenerational equity (Karpudewan, Ismail, and Mohamed2013), sustainable development (Yavetz, Goldman, and Pe’er 2009), and ecologicalfootprint (Esa 2010). But again, the general emphasis of this line of work has beento identify what PSTs do not know. Furthermore, these studies used multiple-choicesurveys to evaluate PSTs’ knowledge of sustainability, but such surveys alone donot capture how PSTs demonstrate their knowledge. We therefore used semi-struc-tured interviews in this study and focused on how PSTs talked about the differenttrade-offs associated with food systems. We turn next to a discussion of other studiesthat have explored participants’ knowledge of food systems.

Knowledge of food systems

Few studies have examined knowledge of food systems among PSTs specifically,but exceptions include those by Trexler and colleagues who conducted semi-struc-tured interviews to explore elementary PSTs’ knowledge of the positive and negativeeffects of using agricultural resources and technologies. In general, most PSTs spokemore elaborately about the negative impacts of pesticides such as pollution of the

Environmental Education Research 3

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

environment than they did about the benefits, such as preventing post-harvest croploss and preventing human disease caused by eating food damaged by pests (Trexlerand Heinze 2001; Trexler and Meischen 2002). In addition, those who had garden-ing and farming experiences tended to have more well-developed schema forimpacts of pesticide use (Trexler and Heinze 2001).

The importance of food-based experiences in developing understanding aboutfood systems has also been suggested in studies examining K-12 students’ knowl-edge of food. For example, high school students who live on a farm or grew up in arural area demonstrated greater knowledge of agricultural concepts and origins offood compared to those from urban areas (Frick et al. 1995). At the same time,Calabrese Barton et al. (2005) found that primary-school-age students who live inurban areas can also tell realistic, factual stories about food and its farm-to-storetransformation when they have personal experiences with food at home. Studentswho did not draw from food-based experiences, in contrast, tended to tell imaginary,creative stories about the transformation of food (Calabrese Barton et al. 2005).Using a questionnaire to assess students’ knowledge of food systems, Harmon andMaretzki (2006) found a positive, statistically significant correlation betweenknowledge of food systems (including agricultural inputs and origins of food) andexperiences with farming or gardening and with producing, purchasing, or preparingfood for the family. These studies therefore suggest the significance of food-basedexperiences in the formation of concepts about food systems.

Regardless of whether students had experiences with food, however, studies haveshown that students tend to lack an understanding of the connections between theresources used in producing, processing and transporting food and the environmentalimpacts of those processes (Bissonnette and Contento 2001; Calabrese Barton et al.2005; Harmon and Maretzki 2006; Tsurusaki and Anderson 2010). In addition, in adiscussion of the supply chain of hamburgers, Tsurusaki and Anderson (2010) foundthat students tended to demonstrate little knowledge of particular locations and actorsin food systems, such as feedlots or the roles of humans in transporting and process-ing food. Furthermore, in their study of high school students’ knowledge of food sys-tems, Harmon and Maretzki (2006) found that most students could not arrange thedifferent components of food systems in a logical or chronological order and haddifficulty identifying the kinds of activities, places, and people that constitute particu-lar components. The general conclusion from these studies has been that students lacksufficient knowledge about food systems and their environmental impacts.

While offering valuable insights about students’ and PSTs’ knowledge of food sys-tems, these studies, like the ones on PSTs’ knowledge of sustainability, have tended tofocus on what people ‘fail’ to understand about particular concepts related to food pro-duction. We seek to contribute to the literature on PSTs’ knowledge of food systemsand sustainability more broadly by avoiding the deficit approach. Specifically, we pro-pose an approach that highlights how people consider issues of sustainability regardingfood systems through the lens of trade-offs and attends to their use of language. We turnnext to the theoretical framework that informs this approach.

Theoretical framework

To understand how PSTs’ use of language demonstrated knowledge of sustainabilityas it relates to food systems, we drew on the constructs of framing, metacognition,and complex causality. We describe each of these constructs below.

4 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Framing

One way to understand how people demonstrate knowledge is to examine how theyframe a particular situation, interaction, or task in the context of a particular topic orarea of study. This notion of framing, which initially came from linguistics as a wayto make sense of interactions among participants (Tannen and Wallat 1987), hasbeen used by education researchers to examine learning interactions (Russ, Lee, andSherin 2012). Within science education specifically, framing has been defined as anindividual’s interpretations or expectations about how to approach knowledge(Hammer et al. 2005; Scherr and Hammer 2009). Each framing is thereforeassociated with a particular epistemological orientation that reveals how theindividual thinks about knowledge (Russ, Lee, and Sherin 2012).

For example, Hammer and colleagues have argued that when students frame alearning activity as an assignment to complete a worksheet, students viewknowledge as consisting of memorized vocabulary and rules (Hammer et al. 2005;Hutchison and Hammer 2010; Scherr and Hammer 2009). In contrast, when studentsframe the same learning activity as an opportunity to make sense of a scientific phe-nomenon, students regard knowledge as something that is personally constructed,and not necessarily something that is in a textbook (Hammer et al. 2005; Hutchisonand Hammer 2010; Scherr and Hammer 2009).

Applying this concept of framing to clinical interviews, Russ and colleagueshave argued that depending on how participants frame the interview, participantsaccess different sources of knowledge. For example, when people frame the inter-view as an inquiry, they take it as an opportunity to construct tentative knowledge inthe moment. When people frame the same interview as an opportunity to be anexpert about a topic, they draw on personal experiences or expertise instead ofrelying on outside sources (Russ, Lee, and Sherin 2012).

How people frame an interview is therefore an indicator of how stable or tenta-tive their knowledge is that can be determined through their verbal behaviors. Inparticular, people’s use of hedging language, such as ‘I am not sure, but …,’ indi-cates their framing the interaction as an inquiry and effort to construct knowledge,thereby suggesting that whatever they say is tentative (Russ, Lee, and Sherin 2012).In contrast, when people speak confidently and frequently refer to their experiencesto describe particular topics or phenomena, this is indicative of the expert frame andsuggests the stability of their knowledge (Russ, Lee, and Sherin 2012). We appliedthis construct of framing by Russ and colleagues in our study to better understandthe degree to which PSTs’ knowledge of trade-offs associated with food systemswas stable or tentative.

Metacognition

We also drew on the construct of metacognition to attend to whether and how PSTs’language demonstrated an awareness of the limitations of their knowledge. Origi-nally introduced in the context of studying children, metacognition is typicallydefined as knowledge about and the ability to monitor, regulate, and evaluate one’scurrent level of understanding (Brown 1980; Flavell 1979). Metacognition alsoentails the ability to acknowledge uncertainty about the accuracy of one’s knowledgeand specify ignorance (Egré and Bonnay 2012; Merton 1987; Wineburg 1998,1999), and such an ability has been shown to be an important predictor of learning

Environmental Education Research 5

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

performance (Tobias and Everson 1996; Wang, Haertel, and Walberg 1990). Whileignorance tends to have a negative connotation, conscious ignorance – or being con-scious about lack of knowledge – has important positive roles in learning (Otero andIshiwa 2014). For example, acknowledging ignorance can be useful in identifyingparticular questions and problems that need to be addressed in order to gain moreknowledge (Merton 1987). Furthermore, the willingness to explicitly recognizeconfusion and specify gaps in knowledge are dispositions necessary for developingadaptive expertise (Hatano and Inagaki 1986), defined as the capacity to solve newproblems and approach unfamiliar situations flexibly using acquired knowledge(Wineburg 1998, 1999).

The ability to admit and specify ignorance about something as complex as thesocial and environmental implications of food systems, then, is particularly impor-tant for current and future educators who teach about these issues because suchmetacognitive skills can help educators identify topics of uncertainty that they needto learn more about in order to teach. We therefore drew upon the notion ofmetacognition in this study by focusing on whether PSTs’ language use reflects theirability to specify their ignorance and recognize uncertainty about the accuracy oftheir knowledge.

Complex causality

To shed light on whether and how PSTs demonstrated knowledge of specific trade-offs associated with food systems, we drew upon the construct of complex causality.In particular, we explored whether and how PSTs discussed two types of complexcause-effect relationships: effects that are far in space and time from their causes,and effects that have multiple causes.

In the first type of complex causality, the relationship between cause and effectis abstract and not obvious (Grotzer 2003; Perkins and Grotzer 2005). In somecases, the causal agent, or the perceived actor that causes an effect, can be cumula-tive in nature and distributed across time, such as the accumulation of greenhousegases in the atmosphere (Grotzer 2003). Research in science education has shownthat students struggle when explaining causal agents that are temporally or spatiallyremote, and that they typically try to look for local causes that are close to the effectand have direct influence (Booth Sweeney and Sterman 2007; Grotzer 2003; Perkinsand Grotzer 2005). Adults also have difficulty perceiving complex causal agents thathave longer-term effects and tend to focus on characteristics of the present momentwhen making predictions (Dorner 1989).

Several reasons have been offered as to why people have difficulty explainingcause-effect relationships that involve spatially or temporally distant causal agents.One is lack of familiarity with such causal agents (Grotzer 2003; Perkins and Grotzer2005). Another has to do with the lack of attention that people typically give to effectsthat take a long time to manifest. Because slow changes, such as the accumulation ofgreenhouse gases in the atmosphere, are difficult to notice, they are not relevant topeople’s daily lives and receive relatively little attention (Grotzer et al. 2013).

Another form of complex causality is the association of multiple effects withmultiple causes (Grotzer 2003). The simplest pattern of causality is one in which Acauses B. More complex patterns include domino causality, which involves a situa-tion in which A causes B, which causes C, and so on, and multilinear causality,which involves multiple causes and/or effects and is visualized in terms of branching

6 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

and radiating structures (Grotzer 2003). Another example of a complex pattern ismediating causality, which involves three agents, with one mediating the effect ofone on another (Grotzer 2003). To understand the trade-offs around organic farming,for example, one needs to understand the multiple causes and effects of the highercosts of organic foods compared to their non-organic counterparts. A few suchcauses include high labor costs for organic farmers, the costs of getting certified asorganic, and public perceptions of the high quality associated with organic foods.Effects can include less affordability, reduction of environmental impact, and promo-tion of human health both among farmworkers and consumers from lowered use ofsynthetic pesticides. At the same time, there are mediating causes that affect theeffects of organic farming, such as the scale at which the farm operates, the types ofcrops that the farm grows, and the distance travelled by the organic foods. Forexample, an organic apple grown in Chile and shipped to the US has a large carbonfootprint that may outweigh the environmental benefits of not using syntheticpesticides.

Developmental research and research in science education suggest that while theability to reason about multiple causes and/or effects tends to increase with age,learners generally tend to assume simple linearity when conceptualizing dynamicsystems initially as opposed to nonlinearity or linearity (Grotzer 2012; Raia 2008).At the same time, the cognitive load of considering multiple cause-effect pathwayscan make it difficult to trace effects back to particular causes (Grotzer 2003).

Understanding time delays and recognizing complex patterns of causality istherefore crucial in being able to weigh the trade-offs associated with using differentagricultural resources and farming methods across time scales. Consequently, weexplored the kinds of short-, medium-, and long-term trade-offs PSTs mentionedwith respect to food systems to gain insights about their understanding ofsustainability.

Summary of the theoretical framework

Drawing upon the notions of framing and metacognition allowed us to focus on howPSTs spoke, and make inferences about whether they demonstrated stable knowl-edge, constructed tentative knowledge, or specified ignorance about trade-offsassociated with food systems. In addition, using the concept of complex causalityenabled us to examine what PSTs said, and specifically, whether PSTs made refer-ences to multiple causes and/or effects and time delays. The question that guidedour study was: In what ways do PSTs demonstrate knowledge of the social and envi-ronmental trade-offs of using agricultural resources and farming methods over theshort, medium, and long terms?

Methods

Participants

Twelve elementary PSTs who were enrolled in or had recently graduated from auniversity-based, post-bachelor teacher credential program located in NorthernCalifornia volunteered to participate in this exploratory study. We recruited the PSTsby sending an email to their instructor that explained our interest in understandinghow PSTs think about food and food systems. Each participant received acompensation of $20.

Environmental Education Research 7

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Demographics

Table 1 describes the backgrounds of the 12 participants (all names are pseudo-nyms). All but one were female3, and four were parents. Every participant, with theexception of Crystal, had some gardening experience.4 There were differences in theparticipants’ preferences for buying food. Specifically, while some indicated makingan effort to buy organic foods, others explained that they avoided buying organicfoods because of the higher prices.5 In addition, the vast majority of participants hadbachelors degrees in the social sciences, and Kacey was the only PST who had afocus on natural science. These participants were therefore representative of elemen-tary PSTs across California who tend to have little to no formal background inscience (California Council of Science and Technology 2010) and the US (Kelly2000).

Data collection

Data collection began in March, 2013 and ended in October, 2013. We conducted60–90-minute semi-structured interviews with each participant. To prepare for these

Table 1. Backgrounds of study participants.

Name Gender# of

childrenGardeningExperience

Purchasingpreferences

Academicbackground

Catherine Female 0 Family has agarden

Tries to buyorganic

BA in history andteacher education

Cecilia Female 0 Had a gardengrowing up

Tries to buyorganic

BA in childdevelopment

Crystal Female 0 None Tries to buyorganic

BA in liberal studies

Cynthia Female 0 Has her owngarden and hadone growing up

Buys what is cheap BA and MA invisual arts

Donna Female 3 Has her owngarden

Buys what is cheap BA in liberal studies

Janet Female 0 Had a gardengrowing up

Buys what is cheap BA in liberal studies

Jason Male 1 Had a gardengrowing up

Buys what ischeap, but alsotries to buy local

BA in liberal studies

Joan Female 3 Have hadgardens of herown

Buys what is cheap BA in childdevelopment

Kacey Female 0 Had a gardengrowing up

Buys what is cheap BA in liberal studiesand concentration innatural science

Lindsay Female 3 Has her owngarden

Used to buyorganic when herchildren wereyounger

BA in childdevelopment

Lisa Female 0 Had a gardengrowing up

Buys organic BA in liberal studies

Liz Female 0 Family has agarden

Buys what is cheap BA in dance/performance studiesand history

8 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

interviews, we developed concept maps to illustrate the social and environmentaltrade-offs associated with using particular agricultural resources and farming meth-ods by interviewing experts in agricultural education. After these experts reviewedthe concept maps (see Appendix 1 for the concept maps), we developed a list ofopen-ended interview questions that probed the extent of PSTs’ knowledge aboutthe different trade-offs without introducing any concepts or words beyond thosegenerated by the participants. Each interview was flexible, as we adapted the ques-tions depending on participants’ responses and asked follow-up questions to encour-age them to elaborate upon concepts that they themselves brought up (Becker 1998;Berg 2007; Merriam 2009). This type of semi-structured interview has been used inscience and agricultural education research as a means to understand students’knowledge and in studies aiming to explore students’ knowledge of food systems(Calabrese Barton et al. 2005; Hess and Trexler 2011; Sherin, Krakowski, and Lee2012; Trexler 2000; Trexler, Hess, and Hayes 2013).

Each interview began by stating that the purpose was to find out the participant’sknowledge of food systems. To set the stage for this, each participant was shownfour tomatoes, each with a different sticker label indicating where it came from andwhether or not it was organically grown, and asked about factors they would con-sider before buying a tomato. We then asked a series of follow-up questions, suchas: What do you notice about these four tomatoes? Which one of these do you thinkis going to be cheaper at the store? What makes you say that? What resources areneeded to grow these tomatoes? What are some of the effects of using thoseresources? Depending on which resources PSTs mentioned and how they describedeach resource, we asked additional probing questions to encourage PSTs to describeas many different kinds of effects as possible. For example, if PSTs mentioned fertil-izers, we asked: Where do the fertilizers go? If PSTs answered that fertilizers couldenter the water, we asked: What do you think might be the effects of fertilizersentering the water?

All interviews were audio-recorded and then transcribed. These interviewtranscripts served as the primary data source.

Data analysis

The analysis of the interview transcripts occurred in several stages. The first stageinvolved an analysis of the trade-offs that PSTs described. Specifically, we consultedboth the experts’ concept maps and academic papers written about the impacts ofmodern industrial agriculture on society and the environment (see Introduction).Each transcript was coded deductively, using descriptive a priori categories we haddeveloped to capture participants’ discussion of positive and negative social andenvironmental impacts6 of using agricultural resources across different time scales:short, medium, and long terms.7 We also attended to any themes that emerged fromthe interviews and created codes accordingly; emergent themes included referencesto direct experiences, indirect experiences, and misconceptions. See Table 2 for adescription of each of the a priori and emergent codes.

To establish reliability of coding, we followed Campbell et al.’s (2013) methodof unitizing the interview transcripts into multiple units of meaning. After the firstauthor and an external researcher coded four of the 12 transcripts independently, wereached an intercoder reliability of .75 on average across the four transcripts. Wefound this to be an acceptable level of reliability, given the complexity of the

Environmental Education Research 9

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Table 2. Coding key.

Codes Definition Examples

Trade-offsShort-termeffects

Use when interviewee discusses andelaborates upon effects that can beexperienced or seen relativelyquickly (several months to a decade)

Smog due to air pollution fromfossil fuels, creation of jobs fromhaving a transport system

Medium-termeffects

Use when interviewee discusses andelaborates upon effects that can beexperienced or seen over severaldecades

Soil compaction and poor soilstructure due to the use of largemachines; cancers due to exposurefrom pesticides

Long-termeffects

Use when interviewee discusses andelaborates upon effects that gobeyond the lifetimes of people andare harder to see directly

Climate change due to burningfossil fuels and the consequent risein sea levels, human migration,spread of tropical diseases

Social Use when interviewee discusses aneffect that affects human health andwell being or society

Creation of jobs from having atransport system, poor treatment ofundocumented farmworkers oftenhired by large farming operations

Environmental Use when interviewee discusses aneffect that affects the health ofplants, animals, and the ecosystem

Death of animals due to pesticideexposure, eutrophication and fishdeath due to fertilizers in water

Positive effect Use when interviewee discusses aneffect that is largely positive

Access to a variety of food year-round due to transportation system;lower costs of food due to use ofmachines that increase productivity

Negative effect Use when interviewee discusses aneffect that is largely negative

Respiratory issues from airpollution; eutrophication

ResourcesFarmworkers Use any time interviewee describes

the backgrounds of farmworkers,their wages, their workingconditions

‘They’re not paid much, they don’thave very good working conditions’

Fertilizers Use any time interviewee describesthe characteristics, origins,functions, and/or varieties offertilizers, which include compost,manure, synthetic fertilizers, plantwaste

‘Natural fertilizers include manure,egg shells’; ‘Compost is nutriet-rich’; ‘There’s different kinds youcan use – cow, chicken, horsemanure’

Fossil fuels Use any time interviewee describesthe characteristics, origins, and/orvarieties of fossil fuels, whichinclude gasoline, or describes whatgasoline is used for

‘We’re running dangerously low onfossil fuels’; ‘Fossil fuels are neededto run farm machines’

Pesticides Use any time interviewee describesthe characteristics and/or varieties ofpesticides

‘Pesticides can get into the watersystem’; ‘organic farmers can’t usea lot of the modern pesticides’

Soil Use any time interviewee describesthe characteristics and/or varieties ofsoil

‘California is prime farming areabecause the soil has a lot ofnutrients’; ‘there are different kinds– there’s soil that has a lot of sand,there’s soil that is clay-based’

Water Use any time interviewee describesthe characteristics and/or sources ofwater used for farming

‘The water comes from rain, rivers’;‘some farms have wells where theyget groundwater’

(Continued)

10 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

concepts and the different codes that could be assigned to each unit of meaning(Krippendorff 2004). Each unit of the transcript where there was disagreement wasdiscussed until we came to a consensus. These discussions enabled us to revise thedefinitions of what counted as an instance of the a priori and emergent categories. Itis important to note that these codes were not mutually exclusive and that a givenunit of meaning was often assigned multiple codes as appropriate. For example,when a PST discussed the negative effects of fertilizers entering the water system onaquatic species, we assigned the codes ‘fertilizers,’ ‘short-term effect,’ ‘negative’and ‘environmental.’ We then used the constant comparative method to code the restof the transcripts. Specifically, we compared each incident of a code with previousincidents of the same code (Glaser and Strauss 1967) across the 12 interview tran-scripts. Through this iterative coding process, in which we went back and forthbetween revising the codes and coding the data (LeCompte and Schensul 1999;Miles and Huberman 1994), we arrived at the coding scheme shown in Table 2.

Table 2. (Continued).

Codes Definition Examples

Farming methodsNon-organic Use any time interviewee describes

the characteristics of non-organicfood, non-organic farms andfarmers, non-organic farmingmethods

‘You probably get a lot more[production] from non-organic[practices]’; ‘Non-organic farms canbe really big’

Organic Use any time interviewee describesthe characteristics of organic food,organic farms, organic farmingmethods, organic farmers

‘Organic farms probably look a lotsmaller’; ‘an organic farmer wouldprobably be more concerned about… flavor and different varieties’;‘organics are more expensive’

Personal experienceDirectexperience

Use any time interviewee describessomething he/she has directlyexperienced, seen, heard, smelled,tasted, touched

‘I went on a field trip with mydaughter to a farm where they don’tuse any kinds of chemicals… theytake all their old plants when theseason’s over and compost them’;‘We had a compost pile, so itbasically would be lawn clippings,table scraps… and you usually justwater it down… and with time, allof that stuff will decompose’

Indirectexperience

Use any time interviewee refers tosomething that he/she has read,seen, heard somewhere (books,articles, videos, news)

‘I’ve read about stopped laborwhere they [farmworkers] have tobend over a lot’; ‘I’ve heard thatorganic farming techniques don’tovertax the land’

Misconceptions Use any time interviewee sayssomething about a resource,practice, or effect that is not accurateor demonstrates partialunderstanding

‘Carbon dioxide disintegrates theozone layer’; ‘organic farmers don’tuse pesticides’; ‘we’re usingmachines a lot more to do their jobs[farm labor], so we’re hiring less ofthem in turn’

Notes: Italicized codes were those that emerged inductively. All other codes were determined deduc-tively before the interviews were conducted. Also, while ‘non-organic’ is not a term that is typicallyused to describe conventionally grown foods, because the participants referred to foods that were notgrown organically as non-organic, we used this language as well.

Environmental Education Research 11

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Once we finalized the coding scheme, we used NVivo, a qualitative data analysissoftware package, to code the data and systematically locate and analyze instances ofwhere and how certain codes were assigned together. Specifically, we used the codingquery function in NVivo to identify and analyze all the instances in the data that werecoded, for example, as short-term, environmental, and negative effects. We repeatedthis process to find and analyze instances in the data of negative environmentaleffects across the medium and long terms, positive environmental effects across thetime scales, negative social effects across the different time scales, and positive socialeffects across the different time scales. We then categorized all the instances that werecoded for a particular type of effect (e.g. medium-term, environmental, negativeeffect) according to the corresponding agricultural resource or farming method.

Following this categorization, we moved onto the second stage of data analysis,which involved examining each unit of coded text in terms of whether and how eachPST hedged, acknowledged ignorance, and indicated knowledge of multiple causesor effects associated with using particular agricultural resources or farming methods.Table 3 shows the language characteristics we attended to, our interpretations ofthose characteristics, and examples from the interviews transcripts. Table 4 illustratesthe three types of complex causality that we attended to – multilinear causality,mediating causality, and complex agency – and corresponding examples from theinterview transcripts and interpretations.

Table 3. Characteristics, interpretations, and examples of PSTs’ use of language.

Characteristics of language Examples Interpretation of language

Expressed certainty orconfidence about aparticular topic or area,often by drawing uponprior experiences to backup explanations

‘I’ve read some about CesarChavez and I was actuallyalive when he was doingsome of his work… so I’veheard a lot, and I lived nearNapa. I think that they havebecome sick… because ofwhat they used [pesticides] ona lot of the food, so stillhaving to fight for rights asfar as… their workingconditions.’ (Lindsay)

Demonstration of stableknowledge (Russ, Lee, andSherin 2012)

Used hedging language,such as ‘I’m not sure but… ,’ ‘probably,’ or ‘Iwould guess that… ,’ tomake speculations aboutparticular effects of usingagricultural resources

‘I’m really not 100% sure[about the effects of fertilizerson water]… I know if it getsin at high enough quantities,it can alter the… aquaticspecies in our rivers… itdepends on how much of aquantity gets out to therivers.’ (Jason)

Demonstration of tentativeknowledge (Russ, Lee, andSherin 2012)

Expressed uncertainty abouta particular topic or areaby saying ‘I don’t know’

‘I think those are… deep inthe ground, and all thosefossils, so… either deadplants or animals… breakingdown, I don’t know. That’sprobably different from oil,but maybe not, but I have noidea.’ (Liz)

Demonstration ofmetacognition or ability toacknowledge and specifyignorance (Merton 1987;Wineburg 1998, 1999)

12 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

To help establish credibility of the study, we followed up with a few of theparticipants and asked for their thoughts about whether our interpretations of theirinterview transcripts was accurate (Lincoln and Guba 1985; Shenton 2004). In addi-tion, as we began to make interpretations of the data, we engaged in peer debriefing(Lincoln and Guba 1985) by seeking feedback from our colleagues on thetheoretical framework we used to guide our analysis and on our interpretations.

Findings

The frequency distribution of the short-, medium-, and long-term social andenvironmental impacts that PSTs mentioned is shown in Figure 1. All PSTs

Table 4. Examples and explanations of complex causality.

Type of complex causality Examples Interpretation

Multilinear causality: causesthat have multiple effects,effects that have multiplecauses, and/or effects thatare also causes

‘I think [organic is moreexpensive] because they[farmers] have to usealternative methods ofkeeping pests away fromfood. I went… [on] a fieldtrip with my daughter to…[an organic] farm, where theydon’t use any kind ofchemical… [and] I just sawhow much work all thattakes. So I figure, it’s just thetime it takes to do thingswithout the chemicals, Iguess, is why it’s moreexpensive.’ (Donna)

Keeping pests away fromfood without using chemicals[cause] leads to increasedtime and labor [effect andcause], which then causesthe higher cost of organicfoods [effect]

Mediating causality: factorsthat mediate or reinforcecause-effect relationships

‘Probably a lot of illegal[undocumented] farmworkerswill get minimal wage pay[because farmers can getaway with this]. And I knowthere’s been a big problemwith… having them bendingover with no breaks and norestrooms to go to… [P]articularly in California, thereare a lot of undocumentedworkers that come up fromMexico, to come work on thefarms because the moneythere is better than the moneythat they could make back inMexico.’ (Lisa)

The poor working conditionsand low wages offarmworkers [the effect] arecaused (in part) by farmershiring farmworkers who areundocumented and thereforevulnerable [the cause] andreinforced by the fact thatfarmworkers do not haveother jobs to turn to

Complex agency: causes thatare temporally or spatiallydistant from their effects

‘The fertilizers eventually canget into the water source…[and] if it gets in at highenough quantities, it canalter… the animals and theaquatic species in our rivers.’(Jason)

Fertilizers applied at the farmeventually enter the watersystem [the cause] cannegatively affect aquaticspecies [the spatially andtemporally distant effect]

Environmental Education Research 13

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

described short- and medium-term effects, but only one quarter mentioned long-termeffects. In addition, a little over 40% talked about both social and environmentalshort-term effects and 75% discussed both for medium-term effects. Only one PST,however, spoke about both social and environmental aspects of long-term effects.The other two PSTs who discussed long-term effects focused on the social impacts.Table 5 elaborates upon these trends by listing the types of trade-offs that PSTs men-tioned. The categorization of the trade-offs is based on whether they were positiveor negative, were social or environmental in nature, and occurred over the short,medium, or long terms. Table 5 illustrates that both the frequency and the total num-ber of different trade-offs mentioned were highest for short-term trade-offs. In con-trast, PSTs’ discussion of medium-term trade-offs focused primarily on use ofpesticides and fertilizers, and only a few PSTs described long-term trade-offsassociated with fossil fuel emissions.

Drawing on the examples listed in Table 5, we now turn to a discussion of howPSTs demonstrated and/or acknowledged limits to their knowledge of short-, med-ium-, and long-term trade-offs. Table 6 offers a summary of whether and how PSTs’discussions of short-, medium-, and long-term trade-offs demonstrated stable ortentative knowledge, metacognition, or understanding of complex causality. Weelaborate upon the findings from Table 6 and begin with a discussion of examplesof how PSTs talked about short-term trade-offs.

Knowledge of short-term trade-offs

All PSTs demonstrated stable knowledge of some short-term trade-offs associatedwith the use of agricultural resources such as fertilizers and pesticides, constructedtentative knowledge about the effects of organic and conventional farming methods,and formed multilinear causal explanations. We illustrate these findings below byusing PSTs’ discussion of US farmworkers and organic farming.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Short-term Medium-term Long-term

Social Both Social & Environmental

Figure 1. Frequency distribution of the kinds of impacts described by PSTs; n = 12.

14 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Table5.

The

trade-offs

ofusingdifferentagricultu

ralresourcesandfarm

ingmethods.

Short-term

Medium-term

Long-term

Social

Positive

•Accessto

avarietyof

food

year-round

becauseof

transportatio

nsystem

•Low

ercostsof

food

dueto

increase

inproductiv

ityandefficiency

ofnon-

organicfarm

susingmachinesand

synthetic

fertilizers

Negative

•Organic

foodsaremoreexpensive,in

partbecauseof

greaterlaborcosts

•Respiratory

issues

from

airpollu

tion

dueto

thetransportatio

nsystem

s,which

usefossilfuels

•Large

farm

ingoperations

(organic

ornot)oftenhire

farm

workers,manyof

whom

areundocumentedandface

poor

working

conditionsandearn

low

wages

•The

poor

working

conditionsthat

undocumentedfarm

workers

face

perpetuate

unjustpractices

andpoverty

amongfarm

workers

•Non-organic

practices

use

pesticides

that

cancause

cancersand/or

otherillnesses

•Water

usecanlead

toless

availablewater

inthefuture,

higher

food

prices,and

potentialconfl

ictsover

water

•Conflictsover

limited

suppliesof

non-renewable

fossilfuels

•Use

offossilfuelsleadsto

emissionsof

carbon

dioxide,which

contributesto

climatechange,which

inturn

causes

sea

levelsto

rise,which

candestroyhomes

ofthosewho

liveon

thecoastand

subm

erge

islands

Environmental

Positive

•Organic

practices,such

ascomposting,

reduceswaste

•Addingcompostmakes

soilhealthier

•Sm

all-scaleorganicpractices

tend

toem

phasizeplantdiversity,which

helps

protectagainstdiseases

Negative

•Pesticides

cankillorganism

sand/or

disturbecosystems

•Pesticides

andfertilizers

canenterthewater

system

andhave

negativ

econsequences

foraquatic

organism

s•

Vulnerability

todiseasebecauseof

lack

ofdiversity

inmanynon-organic

practices

•Eutrophication(due

tofertilizers,whether

synthetic

ornot)inducesalgal

bloomsthat

causeoxygen

depletionanddeathof

marinespecies

•Polar

bearslosing

theirhabitatsand

rising

sealevelsdueto

climatechange

Note:

The

font

type

indicatesthenu

mberof

teachers

who

describedtheseim

pacts:

regu

larfont

means

impactsmentio

nedby

sixor

morePSTs,italics,by

oneto

three

PSTs.

Environmental Education Research 15

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Table

6.Characteristicsof

PSTs’discussionsof

trade-offs

across

thetim

escales.

Short-term

Medium-term

Long-term

Natureof

know

ledge

(framing)

•AllPSTs

demonstratedstable

know

ledgeabouttheeffectsof

agricultu

ralresources,usinglittle

tono

hedginglanguage

and

alluding

toeveryday

experiences

•MostPSTsconstructedtentative

know

ledgeabouttheeffectsof

organicandnon-organicfarm

ing

methods,usinghedginglanguage

•MostPSTsdemonstratedstable

know

ledgeabouttheeffectsof

pesticides

•MostPSTsconstructedtentative

know

ledgeabouttheeffectsof

usingotheragricultu

ralresources

byusinghedginglanguage

•MostPSTsdidnotspontaneously

makeconnectio

nsbetweentheuse

ofagricultu

ralresourcesandtheir

long-term

effects

•A

few

PSTsdemonstratedstable

know

ledgeabouttheeffectsof

clim

atechange,usinglittle

tono

hedginglanguage,butheld

misconceptio

nsaboutthe

connectio

nbetweenfossilfuelsand

clim

atechange

Metacognitio

n•

MostPSTsspecified

ignorance

aboutsomeof

thedetails

ofthe

effectsof

usingagricultu

ral

resourcesandfarm

ingmethods

•MostPSTsspecified

ignorance

aboutsomeof

theeffects

associated

with

theuseof

agricultu

ralresourcesandfarm

ing

methods

•MostPSTsspecified

ignorance

abouttheprehistoricoriginsof

fossilfuelsandtheirform

ationover

millions

ofyears

Com

plex

causality

•MostPSTsdescribedmultip

lecauses

andeffectsof

using

agricultu

ralresourcesandfarm

ing

methods

(multilinearcausality

)

•MostPSTsmentio

nedspatially

andtemporally

distanteffectsof

usingpesticides,fertilizers,and

water

(com

plex

agency

and

multilinearcausality

)•

Afew

PSTsdescribeddifferent

factorsthat

canmediate

theeffects

ofusingagricultu

ralresources

(mediatin

gcausality

)

•The

PSTs

who

talked

aboutclim

ate

change

gave

afew

exam

ples

ofits

temporally

orspatialdistanteffects

(com

plex

agency

andmultilinear

causality

)

16 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Stable knowledge of farmworkers

Most PSTs spoke with little hesitation about the injustices that farmworkers, particu-larly those who are undocumented, often face in terms of low pay, poor workingconditions, and pesticide exposure. Jason, for example, demonstrated knowledge offarmworkers based on having known children whose families were farmworkers.

Interviewer: You mentioned pickers – what do you know about pickers?Jason: I know a lot of ‘em are not legal…And I know a lot of pickers don’t

get paid the same wages…And farmers prefer the illegal ones becausethey can pay ‘em nothing and get more done…

Interviewer: What do you know about their working conditions?Jason: I know Cesar Chavez did a lot to provide more rights for workers, but

it’s still not always recognized…And… there are no facilities out in themiddle of a field… it’s a very labor-intensive… job… I feel bad thatthey’re not getting enough recognition…

Interviewer: You mentioned Cesar Chavez – What do you know about him?Jason: I learned that he was the forefront of fighting for the rights, I know that

he led this huge boycott in grapes to help bring to light the poor condi-tions the workers are put in… [such as] back problems, knee problems… heat stroke…

Interviewer: Where did you learn about all this?Jason: I know because of the areas where I worked [where farmworkers lived]

for 3 years, I wanted to make sure… I understand more about CesarChavez… [and issues around] equality in rights… [so that] I know[where] some of my kids [those he had worked with as an AmeriCorpsmember] are coming from…

Jason drew upon his personal experiences to describe what he knew about short-term social trade-offs. His tone was confident, and his use of ‘I know’ demonstratedthe stability of his knowledge of the underlying politics of immigration that enablesfarmers to get away with some of the consequences of being an undocumentedfarmworker in the US, including poor working conditions, low pay, lack of recogni-tion, and a variety of health issues. He therefore identified a cause of the farm-workers’ low pay and poor working conditions and several resulting healthconsequences, illustrating an understanding of multilinear causality.

Lindsay also referred explicitly to her prior personal experiences of readingabout Cesar Chavez and living near Napa (a wine-growing area in California) in herdiscussion of farmworkers and their working conditions, using little hedginglanguage (see Table 3). When asked to elaborate on her knowledge of workingconditions, Lindsay offered the following description.

I’ve heard about stooped labor where they have to bend over a lot, and then the livingconditions… I’ve read a little bit about… I think there’s a lot of things that could bedone [to improve conditions]…As far as [exposure to] pesticides… that really needsto be controlled in some way.

Lindsay, like Jason, demonstrated stable knowledge about the challenges that farm-workers have faced. In particular, she described several different conditions thatfarmworkers face on the job, including the negative health effects of pesticide expo-sure and poor working and living conditions. Most PSTs likewise drew upon theirprior experiences of seeing farmworkers in the field and/or learning about CesarChavez in their teacher education programs to allude to issues of immigration,worker rights, and poverty. This illustrates evidence of PSTs demonstrating an

Environmental Education Research 17

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

understanding of multilinear causality, in which there are multiple causes thatexplain the poor working conditions that undocumented farmworkers face as well asmultiple effects of those working conditions on the well being of the farmworkers.

Tentative knowledge of organic farming

In contrast to their discussion of the farmworkers, PSTs generally used more hedg-ing language to construct tentative explanations about organic farming, particularlywith respect to the reasons for why organic foods are more expensive than non-organic foods. Donna, for example, offered a tentative explanation based on herexperience of visiting an organic farm (see Table 4). Donna used her prior experi-ences of visiting an organic farm to make a tentative connection – as indicated byher use of ‘I think’ and ‘I guess’ – between the cost of organic foods and the laborneeded to grow food organically. Her explanation also included reasoning aboutdomino causality, whereby keeping pests away from food without using chemicalsled to increased time and labor, which then necessitated the higher cost of organicfoods. Like Donna, most PSTs also used hedging language and referred to hearingor reading about organic foods to identify reasons for the higher costs, such as laborcosts needed to keep pests away, the costs of organic certification, and the percep-tion that organic foods are higher in quality. These PSTs therefore demonstrated anunderstanding of multilinear causality, in which there are multiple causes that leadto the effect of organic foods being more expensive.

A few PSTs, however, were quick to specify gaps in their knowledge andexpressed more uncertainty while also constructing tentative explanations for whyorganic foods are more expensive, as shown in Janet’s interview below.

Interviewer: So what would make you say that [organic food is more expensive]?Janet: I don’t know… [T]he organic stuff always seems to be more expensive,

and I don’t know why…Maybe because the fields – they have to takespecial care. I don’t know.

Interviewer: You just said special care. What do you mean by that?Janet: I have no clue. Thinking here. Maybe like these tomatoes are out in a

field, out in the open so anything can fly in and get inside the tomatoesand they have to kill them. Whereas these [organic] are in an enclosedgreenhouse and so they’re specially taken care of, like in a nice home…I don’t know!

Here, Janet specified ignorance by frequently saying ‘I don’t know’ while alsospeculating about the reasons for the higher costs of organic farming, as indicatedby her use of ‘maybe’ and ‘thinking here.’ PSTs’ discussions of organic farming andits consequences therefore illustrate that the extent to which they used hedging lan-guage and acknowledged limits to their knowledge varied depending upon whetherthey referred to experiences of visiting, reading about, or hearing about organicfarms.

Knowledge of medium-term trade-offs

The majority of PSTs demonstrated stable knowledge of medium-term trade-offsassociated with the use of pesticides, constructed tentative knowledge about theeffects of using other agricultural resources such as fertilizers and water, and formed

18 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

explanations showing some evidence of complex agency and multilinearity. Below,we illustrate these findings by focusing on PSTs’ discussion of pesticides and fertil-izers.

Stable knowledge of the impacts of pesticides

The majority of PSTs used little hedging language in describing the social and envi-ronmental consequences of using pesticides, including illnesses due to pesticideexposure, death of insects and other animals, and destruction of ecosystems, therebydemonstrating knowledge of the multiple effects associated with applying pesticides.This can be seen, for example, when Kacey discussed the use of pesticides.

Interviewer: What do the pesticides do?Kacey: Pesticides… kill off any insects that might attack the crops. And then

they’re kind of like a deterrent for insects and stuff.Interviewer: So what are the effects of applying pesticides?Kacey: [T]he produce is going to have some level of pesticide, depending on

how much you put on or what kind you put on, and then… anything thateats the produce, like people or animals, could intake also a level of thepesticides.

Interviewer: And how do you think the pesticides are applied?Kacey: There’s like this spraying process… I know that sometimes… [it’s]

manually…Interviewer: You mentioned manual: Do you have an idea of who’s involved

[in spraying]?Kacey: Probably… like farmworkers, whoever’s hired by the farmers to work.Interviewer: What do you think might be the effects of spraying pesticides on those

workers?Kacey: They can breathe in heavy doses of the pesticides, which is obviously

really bad for them.

Here, Kacey used little hedging language to identify a cause of pesticide use(keeping pests away from crops) and the effects of pesticide use (negative healtheffects for workers, consumers, and animals), thereby forming a multilinear causalexplanation. Most PSTs demonstrated a similar understanding of multilinear causal-ity. Kacey, along with a few PSTs, also mentioned that the effects would depend onthe quantity and type of pesticide, thereby implying, for example, that somepesticides may be more toxic than others. This illustrates some evidence of thesePSTs’ understandings of mediating causality or the factors that mediate the effectsof pesticides.

Tentative knowledge of the impacts of fertilizers

In contrast to their discussion of pesticides, signs of hedging and acknowledgingignorance were more prevalent as PSTs attempted to explain the ecological costs ofusing fertilizers in agriculture. This can be seen, for example, in Jason’s interview.

Interviewer: Are there other places besides the plant that the fertilizers go to?Jason: [It] eventually can get into the water source… could also go into the

local stream… so… it go[es] off to other places, especially streams, ordrainage ditches that drain out into our rivers.

Interviewer: So what do you think are the effects of fertilizers on the water?

Environmental Education Research 19

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Jason: Hmm… that’s kind of hard… I’m really not 100% sure. I mean, I knowit’s probably playing some sort of factor in it, I’m not sure as to howmuch of a factor.

Interviewer: Do you have a sense of what it could do?Jason: Yeah, cuz I know if it gets in at high enough quantities, it can alter the

… ,what is it, the animals and the aquatic species in our rivers… , it canalso affect some of our little pools that we have out there… they’re nottide pools, but they’re along the rivers a lot, it depends on how much ofa quantity gets out to the rivers… I’m not 100% sure.

Jason used hedging language here, as evidenced by phrases such as ‘I’m not100% sure,’ and ‘hmm, that’s kind of hard.’ He therefore acknowledged the limitsof his knowledge of the effects of fertilizers entering the water system. Nevertheless,when probed further, he attempted to construct knowledge in the moment by specu-lating about what could happen, saying that the impact would depend on the amountof fertilizers that enter the rivers, thereby showing some complexity in his reasoningabout the effects of fertilizers. A few PSTs also mentioned the amount of fertilizersas well as the frequency of application, both of which are variables that determinethe effect of fertilizers. While the majority of PSTs did not mention these mediatingfactors, most nevertheless attempted to form an explanation of the relationshipbetween a cause (fertilizers entering water) and its spatially and temporally distanteffects on aquatic organisms (eutrophication).

Knowledge of long-term trade-offs

In general, most PSTs did not discuss long-term trade-offs associated with the use ofagricultural resources. For example, while all PSTs mentioned that fossil fuels arecrucial in transporting food and in the production of synthetic fertilizers, they allquickly recognized gaps in their knowledge when probed to explain the origins andformation of fossil fuels, and most did not describe a connection between fossil fuelsand climate change. The three PSTs who did make this connection gave a few exam-ples of the spatially and temporally distant effects of climate change, but at the sametime, they held misconceptions about the causes of climate change. We elaborateupon these findings below.

Acknowledging ignorance of fossil fuels

All PSTs were quick to specify their ignorance about the origins of fossil fuels. Thisis illustrated by an excerpt from Donna’s interview below.

Interviewer: So where do you think the gas initially comes from?Donna: The gas station.Interviewer: And where do you think the gas station gets its gas?Donna: From the Middle East. They pump it from the ground. They pump some-

thing from the ground that makes the gas… That’s the extent of what Iknow…

Interviewer: So do you know what gas is or what gas is made of?Donna: Some kind of ethanol… or… ? Oil?

Here, Donna acknowledged ignorance, saying ‘that’s the extent of what I know,’soon after we asked her to explain where the gas station gets its gas. A few PSTsdescribed in more detail the origins and formation of fossil fuels but still hedged indoing so, as illustrated in Liz’s discussion below.

20 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Interviewer: You mentioned gas. Where does gas come from?Liz: Gas comes from… oil…Interviewer: Do you have a sense of what is in oil?Liz: … I don’t really know… I mean… it’s in the earth, so it has to be some

sort of minerals or something but I have no idea. Well, actually wait.Isn’t it like fossils and fossil fuels – is that different from oil? I don’tknow…

Interviewer: So what do you know about fossil fuels?Liz: … I think those are… deep in the ground, and all those fossils, so

… either dead plants or animals… breaking down, I don’t know. That’sprobably different from oil, but maybe not, but I have no idea.

While Liz made metacognitive comments about her knowledge of the originsand composition of fossil fuels, saying ‘I don’t know’ numerous times, she did con-struct tentative knowledge about fossil fuels originating from fossils of plants or ani-mals. Ultimately, however, she ended her discussion by saying ‘I have no idea.’ AllPSTs therefore had varying levels of difficulty describing what fossil fuels are,which may also help explain why the few PSTs who made the connection betweenfossil fuels and climate change did not identify carbon dioxide as a link. We turn tothis next.

Stable conceptions of the causes and effects of climate change

Immediately after her discussion of fossil fuels, we asked Liz to explain some of theeffects of using fossil fuels.

Liz: One is carbon – I can’t remember if it’s monoxide or dioxide, I cannever remember which is which, gets released, and… the hole in theozone layer starts to get bigger… allowing more heat to enter the hole[leading to global warming]…

Interviewer: Are there other effects?Liz: … oil is so needed in so many parts of the world… [and] countries are

at war with each other… [some] people… are realizing that oh, we can’tnecessarily sustain ourselves with the oil, so let’s try to find othersources of energy…we’re gonna have to change… if we want to keepon doing what we do.

While Liz used hedging language when talking about carbon monoxide and car-bon dioxide and admitted that she has difficulty differentiating between the two, sheswitched to a confident, matter-of-fact tone when describing that the gases releasedfrom fossil fuels enlarge the ozone hole, letting in more heat and causing globalwarming. In other words, while she was uncertain about the gases emitted fromburning fossil fuels, she expressed little hesitation when explaining that globalwarming is caused by gases that create a hole in the ozone layer. Liz’s lack of hedg-ing therefore illustrates the relative stability of this common misconception, whichalso came up during Lisa’s interview.

Interviewer: So what are the effects of air pollution [from using fuels]?Lisa: I know in LA… they… did research because it’s a highly polluted city

… and [found that] 9-year-old children had lungs of a life-long smokerfrom breathing in that air… I [also] know there’s a lot of talk about glo-bal warming.

Interviewer: Can you tell me a bit more about what you know about global warming?

Environmental Education Research 21

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Lisa: I know that the carbon dioxide produced disintegrates the ozone layer,and that is what protects us from the sun and holds in the heat, andpretty much stabilizes our environment. So there’s concerns about that.

Lisa shared, with relative confidence, her knowledge of air pollution and globalwarming, referencing things she had seen and read about and beginning her sen-tences with ‘I know.’ When asked later on to elaborate how she learned about globalwarming, she acknowledged that she could have been mistaken about the details ofthe causes of global warming because she saw it online five years ago. Nevertheless,she proceeded to reiterate her conceptions of the causes of global warming: ‘Whencarbon dioxide and ozone mix, carbon dioxide pretty much destroys the ozone. Andsince the ozone is what our atmosphere is, more carbon dioxide means more of thatozone starts eating away at the protective layer.’ Her lack of the use of ‘I’ statementsshowed she was fairly certain about the cause of global warming, thereby suggestingthe relative stability of this misconception.

When asked to describe the consequences of global warming, these PSTs usedlittle hedging language, including melting glaciers, polar bears losing their habitat,and rising sea levels. Liz also spoke about international conflicts over limited sup-plies of oil as a consequence of using gasoline and the need to find alternativesources of energy. This illustrates their attempt to piece together a complex causalexplanation involving multiple temporally and spatially distant effects (complexagency and multilinear causality).

Discussion

Complex social and environmental trade-offs are associated with the use of agricul-tural resources in food systems. The ability to navigate and weigh these trade-offs istherefore crucial if citizens are to make informed purchasing decisions, participate inpublic discourse about food systems, and help build food systems that are socially,environmentally, and economically sustainable. We aimed in this study to explorePSTs’ knowledge of these trade-offs by using an approach that highlighted how peo-ple demonstrate knowledge instead of what they lack. Specifically, we attended tothe language PSTs used and drew upon the constructs of framing, metacognition,and complex causality. We found that the PSTs’ discussions of trade-offs varieddepending on the time scale.

With respect to short-term trade-offs of using agricultural resources, for example,most PSTs demonstrated stable knowledge by alluding confidently and frequently toexperiences of seeing, reading, or hearing about those resources. This finding buildsupon previous studies that have shown the role of direct food-based experiences inconstructing knowledge about food systems (Trexler and Heinze 2001; Trexler,Hess, and Hayes 2013) and suggests the importance of other kinds of less directexperiences. In addition, PSTs’ discussions of agricultural resources indicated anunderstanding of multilinear causality, as illustrated by their explanation of farm-workers and the contexts that shape farmworkers’ experiences, such as the politicsof immigration, worker rights, and poverty. PSTs often cited experiences of learningabout Cesar Chavez in school or seeing farmworkers working in the fields. Indirectexperiences also appeared to facilitate PSTs’ discussion of short-term trade-offsassociated with organic farming. While most PSTs specified gaps in their knowl-edge, PSTs who referred to experiences of visiting an organic farm or reading or

22 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

hearing about organic farming constructed explanations about some of the causesand effects of why organic foods are more expensive than conventional foods. Wetherefore argue that indirect experiences (i.e. seeing, reading or hearing as opposedto growing food directly) can also foster an understanding of the multilinear causal-ity underlying the short-term trade-offs associated with food systems.

Indirect experiences may also be helpful in building knowledge of the medium-term trade-offs associated with food systems. Despite using hedging language morefrequently compared to their discussion of short-term trade-offs, most PSTs wereable to hypothesize about the spatially and temporally distant effects of using agri-cultural resources, such as fertilizers, by drawing upon what they had heard, read, orseen. This is a notable finding, given that few studies have highlighted PSTs’ abilityto speculate about the social and environmental trade-offs associated with food sys-tems. Moreover, previous studies that have examined PSTs’ knowledge of sustain-ability more broadly have been based on surveys (e.g. Esa 2010; Karpudewan,Ismail, and Mohamed 2013; Yavetz, Goldman, and Pe’er 2009), limiting research-ers’ abilities to understand whether and how study participants form tentativeexplanations. By conducting semi-structured interviews, we were able to give PSTsthe opportunity to construct tentative knowledge. This capacity to speculate, basedon prior knowledge or indirect experience, is critical in empowering present andfuture educators to construct knowledge about the complex trade-offs associatedwith food systems.

Most PSTs, however, did not discuss the long-term impacts of using agriculturalresources, such as the relationship between the use of fossil fuels and climatechange. We cannot conclude from this that PSTs lack knowledge of the connectionbetween climate change and fossil fuels. However, the fact that most PSTs did notmake this connection aligns with findings from previous studies showing that peoplehave difficulty describing causal agents (such as fossil fuels) that are remote in timeand space from their effects (Grotzer 2003; Perkins and Grotzer 2005). Moreover,the few PSTs who did make this connection attributed climate change to fossil fuelscreating a hole in the ozone layer, a misconception that has been documented in thescience education literature over the last decade (e.g. Bahar, Bağ, and Bozkurt 2008;Boon 2010).

At the same time, while the three PSTs who mentioned climate change describeda few of its long-term consequences, such as rising sea levels, they did not go intomuch detail. This may be because climate change in itself is a multi-faceted phe-nomenon with complex agricultural, environmental, social, economic, and politicalimplications. Understanding these implications therefore requires knowledge of notonly the science of climate change but also of its human aspects, as informed by avariety of disciplines in the social sciences (e.g. economics, political science) andhumanities (e.g. philosophy) as well as professional fields (business, public health).The spatially and temporally distant nature of the effects of climate change furtheradds to the complexity of understanding the phenomenon (Grotzer, Miller, andLincoln 2012).

In order for PSTs to learn about these complex trade-offs associated with usingagricultural resources, we argue that their ability to specify gaps in their knowledgeis crucial because this can potentially inspire them to form a plan for how to fillthose gaps (Tobias and Everson 1996; Wang, Haertel, and Walberg 1990). The factthat all PSTs in this study were willing to say ‘I don’t know’ and specify their igno-rance as they discussed the trade-offs across the different time scales is therefore

Environmental Education Research 23

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

encouraging. One PST explicitly expressed her desire to find out more about whatshe did not know, and at the very end, said, ‘I have lots of research to do!’ This kindof inquisitive, open-minded spirit, combined with awareness of the limits of knowl-edge, is a crucial disposition for learning about the multitude of complex trade-offsassociated with food systems. While previous studies about people’s understandingsof food systems or sustainability have tended to emphasize their lack of knowledge,our contribution to the literature is to recognize and validate PSTs’ willingness tospecify ignorance. In doing so, our study also begins to speak to the need articulatedby environmental education scholars to shift the purpose of research away fromidentifying what participants do not know, toward helping participants developself-awareness about their knowledge (Wals and Dillon 2013).

Drawing upon the constructs of framing, metacognition, and complex causalitytherefore enabled us to gain nuanced insights into how PSTs demonstrate knowledgeof short-, medium-, and long-term trade-offs associated with food systems whileavoiding the deficit approach that has been used in previous studies. In addition, byusing this theoretical framework, our study begins to respond to the need, voiced inthis journal and by scholars who study environmental education and sustainabilityeducation, for data analysis that is more theoretically grounded and informed by dif-ferent fields (Ardoin, Clark, and Kelsey 2013; Reid and Scott 2006, 2013). Below,we also describe implications of this study for the design of teacher educationprograms.

Implications for sustainability education in teacher education programs

Food is a concrete, tangible, interdisciplinary topic that is relevant for all studentsand can be integrated into standard school subjects, such as science, language arts,and social studies, to teach students about important social, environmental, and eco-nomic issues that the world faces today. Trade-offs associated with food systems canalso be used to explore sustainability issues more broadly. While current US educa-tional content standards do not explicitly include sustainability, the idea of teachingabout sustainability is gaining traction in schools and in teacher education programs(Feinstein 2009; McKeown 2013). The state of Washington, for example, has a setof mandated standards around sustainability that K-12 teachers are to teach, andother states around the country may adopt similar standards in the future (Feinstein2009). One way to prepare PSTs to implement similar standards is to design teachereducation programs that apply the concept of trade-offs as a framework for introduc-ing issues of sustainability and integrating topics, ideas, or pedagogical strategiestypically introduced in literacy, science, or social studies methods classes that PSTstake as part of their training.

Findings from this study offer two implications for the design of such teachereducation programs. First, teacher educators need to draw on and use the priorknowledge, experiences, and reasoning skills that PSTs possess as a foundation uponwhich to help build PSTs’ capacity to understand the multiple forms of complexcausality underlying the trade-offs associated with food systems. Second, in additionto leveraging the knowledge that PSTs already have, teacher education programscould offer a variety of learning experiences that facilitate the construction ofschema about complex trade-offs associated with the food systems. Such experi-ences may include reading, discussing, and raising questions about stories or narra-tives that illustrate less visible, long-term consequences of using different

24 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

agricultural resources. For example, research has shown that lessons from cases orstories illuminating the complex causes of particular problems that occurred in thepast can be applied or extended to understand new problems (e.g. Kolodner 1992).

Another type of learning experience that could be offered in teacher educationprograms is the use of computer-based modeling with graphics or multi-user virtualenvironments (MUVEs) that allow participants to travel back and forth in time andspace to collect, record, and compare information about what they see to formexplanations about changes that occur over time (Grotzer 2012). Grotzer andcolleagues, for example, have developed a curriculum called EcoMUVE that aims tohelp students understand eutrophication and other complex causality embedded inecosystems (Grotzer 2012) and have found that students learned to form causalnarratives with more complex reasoning patterns after their exploring the EcoMUVE(Grotzer et al. 2013).

Implications for sustainability education research

Our study is limited by the lack of other data sources, such as PSTs’ performanceon tasks that involve analyzing articles about food systems or sustainability moregenerally, or observations of PSTs making real-time decisions about what foods tobuy. These data sources would have offered additional nuanced insights about PSTs’understandings of food systems and sustainability. Nevertheless, this study offersseveral implications for research in sustainability education.

To strengthen the transferability of the study’s findings (Lincoln and Guba 1985;Shenton 2004), future studies could attend to how PSTs based in different parts ofthe US or the world talk about trade-offs associated with the food systems as a wayto explore their understandings of sustainability. PSTs in this study, for example, allcame from Sacramento or the Central Valley area, where farming and farmworkersare critically important, which can help explain why they demonstrated stableknowledge of farmworkers. The ways in which PSTs demonstrate knowledge oftrade-offs associated with different agricultural resources, then, may vary dependingon their familiarity with food systems in their local geographical contexts. For exam-ple, PSTs based in the Midwest region of the US, where large-scale, mechanizedcorn and soybean farms are concentrated, may potentially demonstrate more stableknowledge of the social and environmental effects of large-scale farming methodscompared to their counterparts in California.

Future studies could also examine how PSTs’ academic backgrounds shape theirunderstandings of issues related to social and environmental sustainability morebroadly. Most PSTs in this study, for example, had a background in the socialsciences, which may help explain why they described the social effects associatedwith using different agricultural resources more frequently compared to the environ-mental consequences. However, PSTs who have studied environmental science, forexample, may emphasize environmental concerns more.

Another fruitful line of research may be to explore whether and how PSTs’ val-ues or beliefs play a role in their knowledge of sustainability as it relates to foodsystems. Several PSTs in this study, for example, were convinced that organic foodis a fad that will pass eventually in favor of another trend. A few PSTs mentionedplacing trust in government and regulations in terms of food safety, while othersdescribed the importance of buying locally to support the local economy. Studies

Environmental Education Research 25

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

could therefore examine whether and how PSTs’ values shape their knowledge ofsustainability.

Future research could also apply the concept of trade-offs in exploring people’sunderstandings of sustainability as it relates not only to food systems but also othersystems, such as cities, managed forests, fisheries, or supply chains. Ultimately,understanding PSTs’ knowledge of trade-offs associated with these types of social-ecological systems can inform the design of curricula, learning experiences, andpedagogical strategies that prepare future educators and their students to engage inpublic discourse about and weigh different courses of action for building a more sus-tainable world.

AcknowledgementsWe would like to thank the 12 pre-service teachers who participated in this research. We aregrateful to Mason Oliver for his help with interview coding; Fred Bliss, Alexander Hess, andDamian Parr for their feedback on our concept maps; Lee Martin, Colin Dixon, members ofthe EDU 294 class, and the Environmental Education lab members for their thoughtful com-ments on this study; Jon Sorensen, for his help with interview logistics; and to the reviewersfor their helpful comments on this article.

Disclosure statementNo potential conflict of interest was reported by the authors.

Notes on contributorsLina Yamashita is a PhD candidate in science and agricultural education at the School ofEducation, University of California, Davis. Her research explores the pedagogical design ofprograms that aim to foster critical literacy using everyday goods, such as food. She isespecially interested in the development of critical literacy among learners and the kinds oflearning contexts and opportunities that facilitate or hinder this development.

Kathryn Hayes, PhD, is the lead researcher for capacity, leadership and sustainability for theIntegrated Middle School Science Partnership at California State University, East Bay. Herresearch focuses on how distributed leadership, organizational capacity and accountabilitypolicies mediate science education reform at urban schools.

Cary J. Trexler is an associate professor of Agricultural and Environmental Education at theUniversity of California, Davis. He holds a joint appointment in both the School of Educationand the College of Agricultural and Environmental Sciences. His area of research andpractice for the last 20 plus years has been agri-food system literacy and the integration ofthis topic into preservice teacher preparation.

Notes1. Food systems refer to farm-to-fork processes, including agricultural production and trans-

port of food. For the purposes of this study, environmentally sustainable practices referto the use of resources that minimize negative environmental impact or maximize ecosys-tem services, and socially just practices, to the ethical treatment of people who work inthe food system and earn fair living wages.

2. There are other resources used in food systems that could have been considered, such asrenewable energy or people who process, sell, prepare, or serve food, but for the pur-poses of this exploratory study, we decided to limit the study to resources used in grow-ing and transporting food because these are fundamental processes that underlie the foodthat consumers eat.

26 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

3. In the US, the majority of elementary pre- and in-service teachers are females (e.g. seeMalaby and Ramsey 2011). Therefore, the fact that this study only involved one male isnot surprising.

4. The fact that most PSTs in this study had gardening experience may reflect their interestin food, particularly because PSTs self-selected themselves to participate in this study.As a point of comparison, a survey conducted by the National Gardening Association(2009) found that 31% of households in the US grow food in their gardens.

5. Howard and Allen (2010) conducted a survey of consumers across the US and found that86% buy organic infrequently. This proportion is comparable to the proportion of PSTsin this study who did not buy organic.

6. Rather than using ‘trade-offs’ as a code, we analyzed PSTs’ discussion of trade-offs byseparating them into positive and negative effects.

7. The classification of short-, medium-, and long-term impacts is used, for example, inreports about the impacts of climate change (e.g. see Sohngen, Alig, and Solberg 2010).

ORCIDLina Yamashita http://orcid.org/0000-0002-5925-1459

ReferencesArcury, T. A., J. G. Grzywacz, J. W. Talton, H. Chen, Q. M. Vallejos, L. Galván, D. B. Barr,

and S. A. Quandt. 2010. “Repeated Pesticide Exposure among North Carolina Migrantand Seasonal Farmworkers.” American Journal of Industrial Medicine 53 (8): 802–813.doi:10.1002/ajim.20856.

Ardoin, N. M., C. Clark, and E. Kelsey. 2013. “An Exploration of Future Trends in Environ-mental Education Research.” Environmental Education Research 19 (4): 499–520.doi:10.1080/13504622.2012.709823.

Bahar, M., H. Bağ, and O. Bozkurt. 2008. “Pre-service Science Teachers Understandings ofan Environmental Issue: Ozone Layer Depletion.” Ekoloji 18 (69): 51–58.

Becker, H. 1998. Tricks of the Trade: How to Think about Your Research While You’re DoingIt. Chicago, IL: University of Chicago Press.

Belgeonne, C., N. Clough, S. Inman, M. Rogers, and P. Warwick. 2014. Education for Sus-tainable Development and Global Citizenship: Good Practice Case Studies in TeacherEducation. York: The Higher Education Academy. Accessed March 30, 2015. https://www.heacademy.ac.uk/sites/default/files/resources/ESDGC_CaseStudiesinTeacherEducation.pdf

Berg, B. L. 2007. “A Dramaturgical Look at Interviewing.” Chap. 4 in Qualitative ResearchMethods for the Social Sciences. San Francisco: Pearson.

Berry, W. 1990. What Are People for? San Francisco, CA: North Point Press.Bissonnette, M. M., and I. R. Contento. 2001. “Adolescents’ Perspectives and Food Choice

Behaviors in Terms of the Environmental Impacts of Food Production Practices: Applica-tion of a Psychosocial Model.” Journal of Nutrition Education 33 (2): 72–82.

Boon, H. 2010. “Climate Change? Who Knows? A Comparison of Secondary Students andPre-service Teachers.” Australian Journal of Teacher Education 35 (1): 104–120.

Booth Sweeney, L., and J. D. Sterman. 2007. “Thinking about Systems: Student and TeacherConceptions of Natural and Social Systems.” System Dynamics Review 23 (2–3):285–311. doi:10.1002/sdr.366.

Brown, A. L. 1980. “Metacognitive Development and Reading.” In Theoretical Issues inReading Comprehension, edited by R. J. Spiro, B. B. Bruce, and W. F. Brewer, 453–481.Hillsdale, NJ: Erlbaum.

Calabrese Barton, A., P. D. Koch, I. R. Contento, and S. Hagiwara. 2005. “From GlobalSustainability to Inclusive Education: Understanding Urban Children’s Ideas about theFood System.” International Journal of Science Education 27 (10): 1163–1186.

California Council on Science and Technology. 2010. The Preparation of Elementary SchoolTeachers to Teach Science in California. Sacramento, CA: California Council on Scienceand Technology.

Environmental Education Research 27

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Campbell, J. L., C. Quincy, J. Osserman, and O. K. Pedersen. 2013. “Coding In-depthSemistructured Interviews: Problems of Unitization and Intercoder Reliability andAgreement.” Sociological Methods & Research 42 (3): 294–320.

CDC (Centers for Disease Control and Prevention). 2011. “School Health Guidelines toPromote Healthy Eating and Physical Activity.” Morbidity and Mortality Weekly Report60 (5): 1–76.

Chyba, J., M. Kroulik, K. Kristof, P. A. Misiewicz, and K. Chaney. 2014. “Influence of SoilCompaction by Farm Machinery and Livestock on Water Infiltration Rate on Grassland.”Agronomy Research 12 (1): 59–64.

Cooper, J., and H. Dobson. 2007. “The Benefits of Pesticides to Mankind and the Environ-ment.” Crop Protection 26: 1337–1348.

Dewey, J. 1916. Democracy and Education. Mineola, NY: Dover.Dimitri, C., A. Effland, and N. Conklin. 2005. “The 20th Century Transformation of U.S.

Agriculture and Farm Policy.” Economic Information Bulletin 3: 1–14. AccessedNovember 17, 2014. http://www.ers.usda.gov/media/259572/eib3_1_.pdf

Dorner, D. 1989. The Logic of Failure. New York: Metropolitan Books.Egré, P., and D. Bonnay. 2012. “Metacognitive Perspectives on Unawareness and Uncertainty.”

In Foundations of Metacognition, edited by M. J. Beran, J. Brandl, J. Perner, and J. Proust,322–341. Oxford: Oxford University Press. doi:10.1093/acprof:oso/9780199646739.003.0021.

Esa, N. 2010. “Environmental Knowledge, Attitude and Practices of Student Teachers.”International Research in Geographical and Environmental Education 19 (1): 39–50.

Eshel, G., and P. A. Martin. 2006. “Diet, Energy, and Global Warming.” Earth Interactions10: 1–17.

Feinstein, N. 2009. Education for Sustainable Development in the United States of America.A Report Submitted to the International Alliance of Leading Education Institutes. Madi-son: University of Wisconsin-Madison and International Alliance of Leading Education.

Flavell, J. 1979. “Metacognition and Cognitive Monitoring: A New Area of Cognitive-developmental Inquiry.” American Psychologist 34: 906–911.

Frick, M. J., R. J. Birkenholz, H. Gardner, and K. Machtmes. 1995. “Rural and UrbanInner-city High School Student Knowledge and Perception of Agriculture.” Journal ofAgricultural Education 36 (4): 1–9. doi:10.5032/jae.1995.04001.

Glaser, B., and A. L. Strauss. 1967. The Discovery of Grounded Theory. Chicago, IL:Aldine.

Gomiero, T., D. Pimentel, and M. G. Paoletti. 2011. “Environmental Impact of DifferentAgricultural Management Practices: Conventional Vs. Organic Agriculture.” CriticalReviews in Plant Sciences 30: 95–124.

Grotzer, T. A. 2003. “Learning to Understand the Forms of Causality Implicit in ScientificallyAccepted Explantions.” Studies in Science Education 39 (1): 1–74.

Grotzer, T. A. 2012. Learning Causality in a Complex World: Understandings of Conse-quence. Lantham, MD: Rowman & Littlefield Education.

Grotzer, T. A., A. M. Kamarainen, M. S. Tutwiler, S. Metcalf, and C. Dede. 2013. “Learningto Reason about Ecosystems Dynamics over Time: The Challenges of an Event-basedCausal Focus.” BioScience 63 (4): 288–296.

Grotzer, T. A., R. B. Miller, and R. A. Lincoln. 2012. “Perceptual, Attentional, and CognitiveHeuristics that Interactwith the Nature of Science to Complicate Public Understanding ofScience.” In Advances in Nature of Science Research, edited by M.S. Khine, 27–49.Dordrecht: Springer. doi:10.1007/978-94-007-2457-0_2.

Hammer, D., A. Elby, R. E. Scherr, and E. F. Redish. 2005. “Resource, Framing, andTransfer.” In Transfer of Learning: Research and Perspectives, edited by J. Mestre, 1–26.Greenwich, CT: Information Age.

Harmon, A. H., and A. N. Maretzki. 2006. “A Survey of Food System Knowledge, Attitudes,and Experiences among High School Students.” Journal of Hunger & EnvironmentalNutrition 1 (1): 59–82. doi:10.1300/J477v01n01_05.

Hatano, G., and K. Inagaki. 1986. “Two Courses of Expertise.” In Child Development inJapan, edited by H. Stevenson, H. Azuma, and K. Hakuta, 262–272. New York:W.H. Freeman.

28 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Hess, A. J., and C. J. Trexler. 2011. “A Qualitative Study of Agricultural Literacy in UrbanYouth: Understanding for Democratic Participation in Renewing the Agri-food System.”Journal of Agricultural Education 52 (2): 151–162.

Horrigan, L., R. S. Lawrence, and P. Walker. 2002. “How Sustainable Agriculture CanAddress the Environmental and Human Health Harms of Industrial Agriculture.”Environmental Health Perspectives 110 (5): 445–456.

Howard, P. H., and P. Allen. 2010. “Beyond Organic and Fair Trade? An Analysis of EcolabelPreferences in the United States.” Rural Sociology 75 (2): 244–269.

Hutchison, P., and D. Hammer. 2010. “Attending to Student Epistemological Framing in aScience Classroom.” Science Education 94: 506–524.

Karpudewan, M., Z. Ismail, and N. Mohamed. 2013. “Pre-service Teachers’ Understandingand Awareness of Sustainable Development Concepts and Traditional EnvironmentalConcepts.” Asia Pacific Journal of Educators and Education 28: 117–130.

Kelly, J. 2000. “Rethinking the Elementary Science Methods Course: A Case for Content,Pedagogy, and Informal Science Education.” International Journal of Science Education22 (7): 755–777.

Kolodner, J. L. 1992. “An Introduction to Case-based Reasoning.” Artificial IntelligenceReview 6: 3–34.

Krippendorff, K. 2004. Content Analysis: An Introduction to its Methodology. London: Sage.LeCompte, M. D., and J. J. Schensul. 1999. Analyzing and Interpreting Ethnographic Data.

Walnut Creek, CA: AltaMira Press.Lin, B. B., M. J. Chappell, J. Vandermeer, G. Smith, E. Quintero, R. Bezner-Kerr, D. Griffith,

et al. 2011. “Effects of Industrial Agriculture on Climate Change and the MitigationPotential of Small-scale Ecological Farms.” CAB Reviews: Perspectives in Agriculture,Veterinary Science, Nutrition and Natural Resources 6 (20): 1–18.

Lincoln, Y. S., and E. G. Guba. 1985. Naturalistic Inquiry. Newbury Park, CA: Sage.Malaby, M., and S. J. Ramsey. 2011. “The Dilemmas of Male Elementary Preservice

Teachers.” Curriulum and Teaching Dialogue 13 (1/2): 1–17.McKeown, R. 2013. Reorienting Teacher Education to Address Sustainability in the U.S.

Context. White Paper Series, No. 1. Indianapolis, IN: United States Teacher Educationfor Sustainable Development Network.

Merriam, S. B. 2009. Qualitative Research: A Guide to Design and Implementation. SanFrancisco: Jossey-Bass.

Merton, R. K. 1987. “Three Fragments from a Sociologist’s Notebooks: Establishing thePhenomenon, Specified Ignorance, and Strategic Research Materials.” Annual Review ofSociology 13: 1–29.

Miles, M. B., and M. A. Huberman. 1994. Qualitative Data Analysis: An Expanded Source-book. Thousand Oaks, CA: Sage.

Mills, R., and L. Tomas. 2013. “Integrating Education for Sustainability in PreserviceTeacher Education: A Case Study from a Regional Australian University.” AustralianJournal of Environmental Education 29 (2): 152–164. doi:10.1017/aee.2014.3.

Minkoff-Zern, L.-A., and C. Getz. 2011. “Farmworkers: The Basis and Bottom of the FoodChain.” Race, Poverty, and the Environment 18 (1): 17–19.

National Gardening Association. 2009. The Impact of Home and Community Gardening.South Burlington, VT: National Gardening Association. Accessed May 25, 2015. http://www.gardenresearch.com/files/2009-Impact-of-Gardening-in-America-White-Paper.pdf

Otero, J., and K. Ishiwa. 2014. “Cognitive Processing of Conscious Ignorance.” In Process-ing Inaccurate Information: Theoretical and Applied Perspectives from Cognitive Scienceand the Educational Sciences, edited by D. N. Rapp and J. L. G. Braasch, 329–349.Cambridge, MA: MIT Press.

Paoletti, M. G., T. Gomiero, and D. Pimentel. 2011. “Introduction to the Special Issue:Towards a More Sustainable Agriculture.” Critical Reviews in Plant Sciences 30: 2–5.

Papadimitriou, V. 2004. “Prospective Primary Teachers’ Understanding of Climate Change,Greenhouse Effect, and Ozone Layer Depletion.” Journal of Science Education andTechnology 13 (2): 299–307.

Perkins, D. N., and T. A. Grotzer. 2005. “Dimensions of Causal Understanding: The Role ofComplex Causal Models in Students’ Understanding of Science.” Studies in ScienceEducation 41 (1): 117–165.

Environmental Education Research 29

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Raia, F. 2008. “Causality in Complex Dynamic Systems: A Challenge in Earth SystemsScience Education.” Journal of Geoscience Education 56 (1): 81–94.

Reid, A., and W. Scott. 2006. “Researching Education and the Environment: Retrospect andProspect.” Environmental Education Research 12 (3–4): 571–587.

Reid, A., and W. Scott. 2013. “Identifying Needs in Environmental Education Research.” InInternational Handbook of Research on Environmental Education, edited byR. B. Stevenson, M. Brody, J. Dillon, and A. E. J. Wals, 518–528. New York: Routledge.

Russ, R. S., V. R. Lee, and B. L. Sherin. 2012. “Framing in Cognitive Clinical Interviewsabout Intuitive Science Knowledge: Dynamic Student Understandings of the DiscourseInteraction.” Science Education 96 (4): 573–599.

Scherr, R. E., and D. Hammer. 2009. “Student Behavior and Epistemological Framing:Examples from Collaborative Active-learning Activities in Physics.” Cognition andInstruction 27 (2): 147–174.

Shenton, A. K. 2004. “Strategies for Ensuring Trustworthiness in Qualitative ResearchProjects.” Education for Information 22: 63–75.

Sherin, B. L., M. Krakowski, and V. R. Lee. 2012. “Some Assembly Required: HowScientific Explanations Are Constructed during Clinical Interviews.” Journal of Researchin Science Teaching 49 (2): 166–198.

Smith, P., D. Martino, Z. Cai, D. Gwary, H. Janzen, P. Kumar, B. McCarl, et al. 2007.“Agriculture.” In Climate Change 2007: Mitigation. Contribution of Working Group IIIto the Fourth Assessment Report of the Intergovernmental Panel on Climate Change,edited by B. Metz, O. R. Davidson, P. R. Bosch, R. Dave, and L. A. Meyer, 449–540.Cambridge, UK: Cambridge University Press. Accessed November 2, 2014. http://www.ipcc.ch/pdf/assessment-report/ar4/wg3/ar4-wg3-chapter8.pdf

Sohngen, B., R. J. Alig, and B. Solberg. 2010. “The Forest Sector, Climate Change, and theGlobal Carbon Cycle – Environmental and Economic Implications.” In Economic Model-ing of Effects of Climate Change on the Forest Sector and Mitigation Options: A Com-pendium of Briefing Papers, edited by R. J. Alig, 37–66. Portland, OR: U.S. Departmentof Agriculture, Forest Service, Pacific Northwest Research Station. Accessed May 25,2015. www.fs.fed.us/pnw/pubs/pnw_gtr833.pdf

Tannen, D., and C. Wallat. 1987. “Interactive Frames and Knowledge Schemas in Interaction:Examples from a Medical Examination/Interview.” Social Psychology Quarterly 50 (2):205–216.

Tegtmeier, E. M., and M. D. Duffy. 2004. “External Costs of Agricultural Production in theUnited States.” International Journal of Agricultural Sustainability 2 (1): 1–20.

Tobias, S., and H. T. Everson. 1996. Assessing Metacognitive Knowledge Monitoring.College Board Report No. 96-01. New York: College Board.

Trexler, C. J. 2000. “A Qualitative Study of Urban and Suburban Elementary Student Under-standing of Pest-related Science and Agricultural Education Benchmarks.” Journal ofAgricultural Education 41 (3): 89–102.

Trexler, C. J., and K. L. Heinze. 2001. “Prospective Elementary Teacher Understandings ofPest-related Science and Agricultural Education Benchmarks.” Journal of AgriculturalEducation 42 (1): 82–95.

Trexler, C. J., A. J. Hess, and K. N. Hayes. 2013. “Urban Elementary Students’ Conceptionsof Learning Goals for Agricultural Science and Technology.” Natural Sciences Education42: 1–8.

Trexler, C. J., and D. Meischen. 2002. “A Qualitative Study of Prospective ElementaryTeachers’ Grasp of Agricultural and Science Educational Benchmarks for AgriculturalTechnology.” Journal of Agricultural Education 43 (2): 68–81.

Tsurusaki, B. K., and C. W. Anderson. 2010. “Students’ Understanding of Connectionsbetween Engineered and Natural Environmental Systems.” International Journal of Envi-ronmental & Science Education 5 (4): 407–433.

Wals, A. E. J., and J. Dillon. 2013. “Conventional and Emerging Learning Theories: Implica-tions and Choices for Educational Researchers with a Planetary Consciousness.” InInternational Handbook of Research on Environmental Education, edited by R. B.Stevenson, M. Brody, J. Dillon, and A. E. J. Wals, 253–261. New York: Routledge.

Wang, M. C., G. D. Haertel, and H. J. Walberg. 1990. “What Influences Learning? A ContentAnalysis of Review Literature.” The Journal of Educational Research 84 (1): 30–43.

30 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Wezel, A., M. Casagrande, F. Celette, J.-F. Vian, A. Ferrer, and J. Peigné. 2014. “Agroeco-logical Practices for Sustainable Agriculture. A Review.” Agronomy for SustainableDevelopment 34 (1): 1–20. doi:10.1007/s13593-013-0180-7.

Wineburg, S. 1998. “Reading Abraham Lincoln: An Expert/Expert Study in the Interpretationof Historical Texts.” Cognitive Science 22 (3): 319–346. doi:10.1207/s15516709cog2203_3.

Wineburg, S. 1999. “Historical Thinking and Other Unnatural Acts.” The Phi Delta Kappan80 (7): 488–499.

Yavetz, B., D. Goldman, and S. Pe’er. 2009. “Environmental Literacy of Pre-service Teachersin Israel: A Comparison between Students at the Onset and End of Their Studies.”Environmental Education Research 15 (4): 393–415. doi:10.1080/13504620902928422.

Environmental Education Research 31

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Appendix

1

32 L. Yamashita et al.

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5

Environmental Education Research 33

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alif

orni

a D

avis

] at

08:

13 1

9 A

ugus

t 201

5