5
Examples of Farming System Types for Improving Sustainability

One of the underlying themes of this report is the tension between the rapid specialization of much of U.S. agriculture in the last few decades and its resulting high production of individual commodities (Chapter 2) with the requirements of robustness, resilience, and appropriate levels of environmental integration in sustainable production systems (as discussed in Chapter 1). That tension revolves around the balance between the “industrial philosophy” and “agrarian philosophies” (Box 1-7) and varies among different commodities and environments. This chapter illustrates a few system types that lie within the complex matrix of that balance. They represent modifications within industrial approaches, and, in some cases, a more aggressive departure toward an agrarian approach. Chapters 3 and 4 highlight advances in the scientific understanding of different management practices and approaches that can contribute to improving productivity and environmental, economic, and social sustainability. The practices are central to the examples below because they are components of a larger farming system.

“System” is interpreted in a broad sense, from the individual farm agroecosystem to the wider ecological system or biome. The systems approach recognizes the importance of interconnections and functional relationships between different components of the farming system (for example, plants, soils, insects, fungi, animals, and water). It also stresses the significance of the linkages between farming components and other aspects of the environment and economy. Understanding how the components function individually and the outcomes each produces becomes the foundation of systems agriculture research. The aggregate outcome of applying those practices in concert cannot be predicted from simply combining the anticipated outcome of each practice because they interact with one another. In some instances, the combination of practices has complementary or synergistic relationships; in other instances, combining two practices might have unintended negative consequences.

A systems approach to agriculture is generally guided by an understanding of agroecology, as a scientific basis, and agroecosystem interactions. Agroecology applies ecological concepts and principles to the design and management of agricultural systems to im-



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5 Examples of Farming System Types for Improving Sustainability O ne of the underlying themes of this report is the tension between the rapid spe- cialization of much of U.S. agriculture in the last few decades and its resulting high production of individual commodities (Chapter 2) with the requirements of robustness, resilience, and appropriate levels of environmental integration in sustainable production systems (as discussed in Chapter 1). That tension revolves around the balance between the “industrial philosophy” and “agrarian philosophies” (Box 1-7) and varies among different commodities and environments. This chapter illustrates a few system types that lie within the complex matrix of that balance. They represent modifications within industrial approaches, and, in some cases, a more aggressive departure toward an agrarian approach. Chapters 3 and 4 highlight advances in the scientific understanding of different management practices and approaches that can contribute to improving produc- tivity and environmental, economic, and social sustainability. The practices are central to the examples below because they are components of a larger farming system. “System” is interpreted in a broad sense, from the individual farm agroecosystem to the wider ecological system or biome. The systems approach recognizes the importance of interconnections and functional relationships between different components of the farm- ing system (for example, plants, soils, insects, fungi, animals, and water). It also stresses the significance of the linkages between farming components and other aspects of the environment and economy. Understanding how the components function individually and the outcomes each produces becomes the foundation of systems agriculture research. The aggregate outcome of applying those practices in concert cannot be predicted from simply combining the anticipated outcome of each practice because they interact with one another. In some instances, the combination of practices has complementary or synergistic relationships; in other instances, combining two practices might have unintended negative consequences. A systems approach to agriculture is generally guided by an understanding of agro- ecology, as a scientific basis, and agroecosystem interactions. Agroecology applies ecologi- cal concepts and principles to the design and management of agricultural systems to im- 

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 TOWARD SUSTAINABLE AGRICULTURAL SYSTEMS IN THE 21ST CENTURY prove sustainability (Gliessman, 1998; Altieri, 2004; Wezel and Soldat, 2009). Agroecology provides a framework to integrate the biophysical sciences and ecology for management of agricultural systems. It emphasizes the interactions among all agroecosystem components (for example, biophysical, technical, and socioeconomic components of the farming system) and recognizes the complex dynamics of ecological processes (Vandermeer, 1995). The ap- proach aims to maintain “a productive agriculture that sustains yields and optimizes the use of local resources while minimizing the negative environmental and socio-economic impacts of technologies” (Altieri, 2000). When used in agriculture, agroecosystems have been defined as “communities of plants and animals interacting with their physical and chemical environments that have been modified by people to produce food, fiber, fuel, and other products for human con- sumption and processing” (Altieri, 1995). Agroecosystem design has been recognized as an important part of an agroecological approach, which is a more holistic concept of inte- grated resource management and understanding complex interactions than a reductionist approach (Swift et al., 1996). This chapter uses a few farming system types to illustrate how they combine practices and to discuss the potential environmental, social, and economic outcomes. (See Box 2-1 for articulation of the distinction between “farming system”—the integrated system of a single farm management entity—and a “farming system type”—aggregations of farming systems defined by commonalities of commodity, management practices, or farming system ap- proach.) Specifically, the organic, integrated crop–livestock, pasture-based livestock, low- confinement hogs, and perennial grains system types are used in this chapter to represent commonalities of commodity, of specific management approach to those commodities, or of a particular philosophical or scientific approach to farming system management. The integrative perspective of how the components interact with each other in a system and the study of the potential outcomes of those interactions provide valuable information for designing, implementing, and operating a farming system that achieves multiple sustain- ability goals. Beyond the boundary of a farm, many elements of sustainability, such as product and market diversity and resilience, water resource quality and use, elements of ecosystem health, and community well-being, are highly influenced at landscape, water- shed, and regional scales. Sustainability, thus, suggests and requires in most instances an appropriate mix and location of farming system types. The last part of this chapter dis- cusses agricultural sustainability at the landscape level. ORGANIC CROPPING SYSTEMS The organic approach to farming, and specifically to cropping systems, is of scientific interest as an alternative type of system to the conventional type for several reasons: • The organic approach is driven by a philosophy of using biological processes to achieve high soil quality, control pests, and provide favorable growing environ- ments for productive crops, and by the prohibition of use of most synthetically produced inputs. For farm products to meet organic standards, farmers either substitute “organic” inputs (which are usually expensive) or use “biological struc- turing” (illustrated by use of practices described below) to achieve a high level of internal ecosystem services in their farming systems to permit high efficiency and productivity. Most productive organic farms are highly integrated and use what is referred to as a holistic approach to manage agricultural operations and their processes and impacts (Vandermeer, 1995; Gliessman, 1998; Altieri, 2004). (See the

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 EXAMPLES OF FARMING SYSTEM TYPES FOR IMPROVING SUSTAINABILITY discussion of “contending philosophies” in Box 1-7.) Organic farming systems represent an expression of the agrarian philosophy and can provide cost data for that position of the spectrum. • There is an ongoing database of the numbers and types of certified organic farms, which features their production and marketing characteristics in the United States (USDA-ERS, 2009b; USDA-NASS, 2009) and on a global basis (Willer et al., 2008). • Farmers have developed organic cropping systems for most major crop commodi- ties and are located in nearly all major agricultural ecoregions of the United States (USDA-NASS, 2009). • While they represent a small portion of total U.S. crop production, organic crop farmers had $1.1 billion in sales from 14,900 farms in 2007 (USDA-NASS, 2009). As discussed in Chapter 1, many nonorganic farms lie somewhere between the con- ventional and organic continuum because they include some organic approaches and ma- terials in their farming systems out of concern for the environment, human health, input costs, and other factors (for example, the Bragger Farm, Thompson Farm, and Green Cay Farm in Chapter 7). Yet, because much of the research literature is based on comparisons of a stylized organic farm versus a stylized conventional farm, many comparisons in this section can be considered assessing farms at opposite ends of the continuum. In selecting organic as an alternative example, the committee is in no way implying that U.S. agriculture should completely turn aside from modern, synthetically derived nutrients, pesticides, or pharmaceuticals. The example illustrates, however, the success that farmers have had with an ecological approach and the degree to which it can be environmentally and economi- cally competitive. Principles and Practices of Organic Farming Organic farming has evolved over many years since it started in Europe in the early part of the 20th century. Several “schools” of philosophy and practice are used to some extent today, as articulated in an extensive practitioner-written literature over the last 100 years (Harwood, 1990). The principles, in most cases, are consistent with scientific theory for ecosystem functioning (Drinkwater, 2009). Several guidelines for biodynamic systems are outside of present scientific theory. However, the majority of organic farms today are guided by either local or international certification requirements assembled through broad farmer and industry collaboration to regulate the rapidly growing marketplace for organic products. Some practices have been reasonably well researched, while studies on others are sparse. Products of some specialty approaches, such as biodynamic, have local or highly targeted niche markets. The following principles and practices, from popular organic lit- erature, represent popular beliefs and values of practitioner-derived systems: • Understanding and managing biological processes to regulate balance, flow, and timing of nutrient levels and availability; achieve pest-predator balance; and main- tain healthy and productive crops and animals. • Avoiding synthetic chemicals. Organic agriculture does not permit the use of syn- thetic chemical pesticides and fertilizers. An organic management approach needs to go beyond substitution of chemical inputs by approved organic inputs and needs to include the principles and practices explained here. • Building healthy soil. Organic farming focuses on building healthy and fertile soil that has high microbial activity, is rich with beneficial and diverse microorganisms,

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 TOWARD SUSTAINABLE AGRICULTURAL SYSTEMS IN THE 21ST CENTURY and is well-balanced in organic matter and humus. Good soil health is attained largely through cultural and biological management methods and use of natural organic inputs. Building and maintaining healthy soil is regarded as a key factor in maintaining plant health, which is thought to help avoid pest and disease problems by preventing crop stress or nutrient imbalance. Soil health is understood to be a basis for maintaining healthy balances of soil organisms in the farm (USDA-SARE, 2009). Nutrient cycling and regulation of the flows and temporal availability of nutrients to crops is a key goal of soil management. • Managing biota within the system. Soil fauna are seen as critical to a healthy soil. Pest-predator balance within the soil and across the landscape is regarded as im- portant to all systems, but is critical to many fruit and vegetable crops. • Cycling nutrients. Organic agriculture aims to foster the cycling of nutrients and energy within and beyond the farming system. The cycling of energy and materials links the living organisms to the nonliving parts of the systems. Microorganisms cycle energy and chemicals from dead organic matter back into food chains (Lindeman, cited in Golley, 1993). Nutrient cycling is fostered in organic farms us- ing various methods, including making and using compost, incorporating cover crops, and integrating crop residues. • Conserving biodiversity and working with ecological processes and ecosystem functions. Organic farming aims to enhance biodiversity in and around the farm because it is believed that biodiversity can help maintain a balanced ecosystem. Organic farmers attempt to work with and enhance beneficial ecological processes and to take advantage of ecosystem functions. For example, farmers try to enhance ecosystem functions by planting diverse plants on the farm to attract beneficial insects. • Adapting to local conditions to maintain balance. As in all farming systems, no uni- form “prescriptions” for organic farming practices work for all farms. The methods are not standardized and have to be adjusted to local conditions. Crops need to be balanced with local growing conditions and ecosystem. Organic growers will likely change their practices over time as they learn innovations and as they adapt their methods to evolving environmental and economic conditions. Many biophysical interactions are important to developing a fully integrated systems approach to organic farming. The intent is to analyze, manage, and enhance favorable in- teractions, rather than focus on specific technological responses or on input applications to solve problems. Those interactions are illustrated in Box 5-1, which is adapted from a guide used for vineyard management of a large organic grape grower in California. Impact on Productivity and Environmental Sustainability Yield In general, organic production systems produce lower yields than conventional pro- duction in developed countries. (See the case study on the Lundberg Family Farms in Chapter 7.) In meta-analysis studies comparing organic and conventional yields, Stanhill (1990) and Badgley et al. (2007) found organic yields per hectare to be 9 and 8 percent lower, respectively. Posner et al. (2008) found that organically managed corn in Wisconsin yielded 87 percent of corn produced in a traditional corn–soybean rotation; organic soybean yields reached 92 percent of their conventional counterpart. Similarly, organic corn in a Minnesota

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 EXAMPLES OF FARMING SYSTEM TYPES FOR IMPROVING SUSTAINABILITY BOX - P ractices Used to Manage Systems Interactions in an Organic System Pest and Disease Nutrient Crop and Noncrop Management Management Vegetation -Use plants to attract -Add compost or -Rotate crops to better beneficial insects. manure. control weeds, pests, -Use biocontrol -Use of cover and diseases; increase methods. crops as green soil moisture; and -Use approved organic manure. improve nutrient use pesticides selectively. efficiency. -Manage soil to -Plant cover crops to suppress diseases. prevent soil erosion and provide nutrients. -Include diverse plants to maintain biodiversity and enhance biological Soil Management control of pests, Water/Watersheds weeds, and diseases. -Use conservation -Provide vegetation to tillage to reduce soil -Use water-efficient provide natural habitat erosion and therefore irrigation systems. for wildlife. decrease sediment -Install drainage -Plant riparian plants runoff. systems. to reduce nutrient -Include organic -Monitor soil runoff. inputs to maintain soil moisture. -Manage weeds by carbon and fertility. -Protect watershed mechanical means. from runoff. Crop Characteristics Composition and Yield Food Quality Examples of systems interactions are: • rop rotations are used to manage soil and nutrients. Cover crops can be selected to take up nutrients C not used by the main crops and then be plowed into the soil to provide nutrients. Water use needs to be considered when selecting cover crops because some of them could increase water use substantially. • oil management has influential interactions with pest and disease management partly because good S continued

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 TOWARD SUSTAINABLE AGRICULTURAL SYSTEMS IN THE 21ST CENTURY BOX - C ontinued soil management and healthy soil help keep the plants strong and healthy and improve their resistance to pests and disease. The use of excess nitrogen in the soil can provoke some pest and disease prob- lems, but inadequate nutrients, organic matter, or minerals can also weaken the plants and increase susceptibility to diseases. • n organic farm typically uses integrated pest management (IPM) that includes biocontrol agents and A practices and selective use of organic pesticides. In that context, actions can be taken to restore and enhance pest-predator balances. The mere presence of an insect pest does not necessarily constitute a problem; the decision on when to intervene is made on the basis of monitoring, using damage thresholds, and understanding the life cycles of the insects and the causes of outbreaks. • ater and watershed management interact with soil, pest, and weed management to affect crop W growth and environmental effects. For example, the use of excess water or inadequate drainage systems can lead to excess weeds and canopy growth that might provoke pest problems or provide a favorable environment for certain root pathogens. Appropriate soil management can decrease soil erosion and thereby can reduce sediment runoff. Soil management can also improve water infiltration into soil and reduce water use. • over crops have many interactions with and effects upon soil, water, crops, and weeds. Planting C cover crops can increase soil fertility and organic matter, increase soil biodiversity and microbial activity, prevent erosion and runoff, protect or improve water quality, attract beneficial insects, and improve soil structure. SOURCE: Adapted from Thrupp (2003). study had yields 91 percent of those from a conventional two-year rotation, while corn pro- duced with low levels of inputs only trailed the conventional yields by 3 percent. In a six- year study on cotton production in the San Joaquin Valley, California, Swezey et al. (2007) reported that cotton grown under organic management had consistently lower yield than under conventional management. Average yield over six years for cotton under organic management was 19 percent lower than for cotton under IPM and 34 percent lower than for conventional management. Nutrient Cycling and Soil Quality Organic farmers commonly use cover crops, legumes, compost, animal and green ma- nures, and animal byproducts (fish, bone, and blood meals) in their soil-building and nutri- ent management programs. In comparison studies with organic and conventional farming systems, scientists (Reganold et al., 1993, 2001; Mader et al., 2002; Pimental et al., 2005) have found organic farming systems to have better overall soil quality, as measured by soil prop- erties such as more organic matter, better structure, less compaction, more earthworms, and greater microbial activity and diversity, than their conventional counterparts. Water Quality Organic farms often have smaller nutrient surpluses than do conventional farms (Kasperczyk and Knickel, 2006; Kustermann et al., 2010). Comparative studies on soil nu- trient and water dynamics of organic and conventional farms usually show significantly lower leachable nitrates in organic systems (Stolze et al., 2000; Shepherd et al., 2003; Kramer

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 EXAMPLES OF FARMING SYSTEM TYPES FOR IMPROVING SUSTAINABILITY et al., 2006). The lower leachable nitrates in organic systems could be because they operate at lower levels of nitrogen application, and because nitrogen in organic systems is bound to organic fertilizers, such as composts and manures, when added or incorporated in the soil. Organically managed soils have been shown to store nitrogen more efficiently than their conventional counterparts (Clark et al., 1998). Other organic practices that minimize nitro- gen losses are wide crop rotations, cover crops, and intercrops (Kasperczyk and Knickel, 2006). Although data on phosphorus loss from organic systems are limited, Lotter (2003) found phosphorus loss from leaching, runoff, and erosion in organic farming systems to be lower than in comparable conventional systems in all studies found. The small nutrient surpluses in organic farms reduce the risk of nutrient (especially nitrogen) pollution from agriculture to rivers, lakes, wetlands, and coastal oceans. Han et al. (2009) reported that if farmers choose organic practices and reduce fertilizer use, nitrogen pollution levels could decrease to below present-day levels. They used existing data on ni- trogen levels in rivers across 18 watersheds in the Lake Michigan basin and from five time intervals between 1974 and 1992. The researchers projected future nitrogen fluxes under three land-use and two climate scenarios: 1) business as usual, 2) increased dependence on organic farming, 3) increased fertilizer use from corn-based ethanol production, 4) a 5 percent increase in rainfall, and 5) a 10 percent increase in rainfall. The study revealed that the combined effect of 10 percent more rainfall and more ethanol production would increase nitrogen levels in rivers by 24 percent. However, increased use of organic farming practices could reduce nitrogen levels in rivers by 7 percent, even if rainfall increased by 10 percent. In southern Michigan, organic rotations using compost leached an average of 35 kg/ha of nitrogen per year compared to 53 kg/ha of nitrogen per year for conventional systems (Sanchez et al., 2004), a 34 percent reduction. Weeds Weed control is one of the greatest challenges to yield productivity and economic prof- itability in organic systems. Seeding in organic grain systems is typically conducted later in the spring than in conventional systems to take advantage of the nitrogen in cover crops and to give weeds an opportunity to emerge. Soybean is particularly susceptible to weed competition. Cavigelli et al. (2008) showed that the yield difference between organic and conventional soybean in a Maryland experiment could be explained solely by the increased weed problem in the organic field. In a Wisconsin study, corn yields were 72 to 84 percent of conventional production in years with wet conditions (Posner et al., 2008). Soybean yields under the same conditions were 64 to 79 percent of yields for the conventional crops. However, in years where weather conditions were favorable and weed pressure was low, yields from organic and low-input systems were comparable (Porter et al., 2003; Posner et al., 2008). Organic farms tend to rely on hand labor for weed control more heavily than do con- ventional farms. In a survey of 59 tomato farms in Indiana, Hillger et al. (2006) found that farmers generally reported more hours of hand weeding for fields under organic man- agement than for those under nonorganic management. Swezey et al. (2007) found that production cost of cotton grown under organic management is higher than nonorganic management primarily because of the greater hand-weeding costs and lower productivity. Although improvements have been made in tillage machinery for controlling weeds in organic systems, results from research and experience suggest that additional research is needed in economical weed control for those systems. (See also Chapter 3.)

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 TOWARD SUSTAINABLE AGRICULTURAL SYSTEMS IN THE 21ST CENTURY Greenhouse-Gas Emissions Organic crop production could have lower greenhouse-gas emissions than conven- tional production because the former does not use synthetic fertilizers or pesticides that require fossil fuel to produce. Meisterling et al. (2009) conducted a lifecycle assessment to compare the global warming potential and primary energy of conventional and organic wheat production. Their model estimated that the global warming potential of producing 0.67 kg (for a 1 kg loaf of bread) of wheat is 190 g of carbon dioxide equivalent (CO2eq) using conventional production and 160 g CO2eq using organic production. Those modeled estimates, however, include high uncertainties associated with N2O emitted from fields and soil carbon sequestration because excess nitrogen input can increase N2O emission in either conventional or organic production. Nitrous oxide release is correlated more with overall soil nitrogen levels and mineralization amounts than with source of nitrogen input. Loss of soil carbon and N2O emissions can be reduced by using best management practices in either conventional or organic production (Meisterling et al., 2009). In a long-term ecological re- search experiment in Michigan, organic treatments were found to have nitrous oxide (N2O) greenhouse warming similar to conventional no-till, low-input rotation with legumes and perennial alfalfa in spite of having no fertilizer N input (Robertson et al., 2000). (See also Table 3-1 in Chapter 3.) Net greenhouse warming potential for the organic system was less than half that of standard conventional with full tillage, but higher than for no-till due to the higher soil carbon gains from no-till. Systematic assessment of greenhouse-gas emissions of different cropping systems or system types over the lifecycle of crop production is sparse. Economic Impact The economics of organic cropping systems has considerable variation by regions of the United States and by different crops. Organic crop yields per acre are generally lower and labor requirements are often higher than in conventional agriculture systems. However, purchased input costs are less than conventional agriculture so that profits per acre are typically only slightly lower than conventional agriculture. Most organic farmers gain price premiums that range from 5 percent to more than 70 percent of the market price obtained by conventional products (Greene et al., 2009; USDA-ERS, 2009b). Fruits and vegetables account for more than 37 percent of organic food sales, which include processed products. The profits per acre of organic farming can significantly exceed those of conventional agriculture. The most accurate comparisons between organic and conventional agriculture are seen across crop rotations rather than between specific crops. Moreover, organic agriculture is often a favorable alternative in regions where farmers lack access to synthetic inputs be- cause of the inability to purchase inputs or absolute lack of physical access to inputs, or in regions with a large labor supply (as in many developing countries). In a long-term farming systems trial at the Rodale Institute in Pennsylvania, the net returns per acre for the conventional system were slightly higher than the net returns per acre for the organic system without premiums during the period of 1991 to 2001 (Pimental et al., 2005). Production costs per acre for the organic system were lower. Total labor for the organic system was higher, but because it was spread more equally through the growing season, the organic system had fewer off-farm hired workers. Organic corn production over the 10-year period was more profitable per acre than conventional corn, but organic corn was not grown as often in the rotation because of the need for soil-building crops. When all land, cover crops, and input costs were calculated, given the frequency of each crop in

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 EXAMPLES OF FARMING SYSTEM TYPES FOR IMPROVING SUSTAINABILITY the rotation, production costs per unit of output were 10 percent higher for organic corn, soybean, wheat, and hay. Delate et al. (2003), however, found net returns for corn within the organic corn–soybean–oat and corn–soybean–oat–alfalfa rotations were significantly greater than conventional corn–soybean rotation returns on the basis of the market prices for the year of study. Lotter (2003) reviewed numerous comparisons of organic versus conventional agricul- ture in the United States and worldwide. He concluded that despite the lower yields of organic crops compared to conventional crops, organic systems can still be more profitable than conventional systems because of lower input costs and organic price premiums. When organic premiums were not included, conventional systems were generally more profitable. However, Welsh (1999) noted that the differences within a given system (for example, organic versus organic, conventional versus conventional) were often greater than the differences between the two systems and that the local environment had a greater effect on their relative performance. More specifically, Mahoney et al. (2004) found that the direct production costs for corn in a conventional two-year rotation were $60 per hectare more than corn produced in a two-year or four-year low-input rotation and $96 per hectare more than that of a four- year organic rotation. In soybean, the organic or low-input systems had a slight advantage of $13–$18 per hectare in savings over conventional production. The use of petroleum-based chemicals make nonorganic agriculture more vulnerable to the volatility of crude oil prices compared to organic agriculture (Scialabba, 2007). Organic practices tend to be more labor intensive (Klepper et al., 1977; Pimental et al., 2005) and often need more intensive management time (Porter et al., 2003) than conven- tional agriculture. In general, unpaid family members provide a larger proportion of the overall farm labor (Tegegne et al., 2001; Macombe, 2007; MacRae et al., 2007). As a result, the economic performance of organic farming systems can depend heavily on the input costs attributed to unpaid family labor (Hanson et al., 1997; Brumfield et al., 2000). For example, a comparison of wheat farmers in the Mid-Atlantic found that organic farms were more efficient than conventional farms by $34/ha in terms of cash operating expenses. However, when opportunity costs, including unpaid family labor, were incorporated, the fortunes were reversed—organic costs exceeded those of conventional by almost $100/ha (Berardi, 1978). Organic farmers in this study also averaged four more hours of labor per hectare than their conventional colleagues. In fruit and vegetable farms, an organic system with 50 percent organic premiums was more profitable than the conventional or integrated apple production systems (Reganold et al., 2001). For all three systems to break even (when cumulative net returns equal cumu- lative costs) at the same time, price premiums of 12 percent for the organic system and 2 percent for the integrated system would be necessary to match the conventional system. Walsh et al. (2008) noted that for organic apple production in the humid Mid-Atlantic, the organic price premium required to break even with the conventional production system was greater than the premiums currently offered by the market. Brumfield et al. (2000) reported that organic sweet corn was 2 percent more profitable than conventionally grown sweet corn in New Jersey. Economic analyses of organic production of California specialty crops also have shown higher profitability than conventional counterparts (Klonsky and Tourte, 1998). The rapid rise in consumer demand for organic products and the concomitant growth of the organic market have brought important economic opportunities and benefits to producers, as discussed in Chapter 6. However, the ability of farmers to gain access to and advantages from the growing organic market depends partly on their marketing strategies and their location because of considerable regional variations.

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0 TOWARD SUSTAINABLE AGRICULTURAL SYSTEMS IN THE 21ST CENTURY Several economic analysts have also addressed questions about the scale of organic production. It is often argued that organic production is more conducive and successful for small- or medium-scale operations because organic farming usually requires more in- tensive management and labor requirements per unit of land, and because of biophysical aspects, such as difficulties in maintaining high levels of biodiversity at larger scales (Hall and Mogyorody, 2001). However, recent studies and prominent organic farming businesses, including several case studies in this report, show that large-scale organic farming systems can also be economically profitable and successful (for example, the Lundberg Family Farms and Stahlbush Island Farms described in Chapter 7). Indeed, by 2007 the average gross sales on U.S. organic farms (and degree of market concentration) were similar to farm sales by size category among conventional farms (USDA-NASS, 2009). Those sales data demonstrate clearly that most organic systems with their high levels of biological structuring through crop rotation, use of cover crops, IPM, and other commonly used or- ganic practices can be applied across the full spectrum of scales if farmer monitoring and management systems are adequate. Social Impact Labor Practices Most published literature and policy discussions about the treatment of farm labor in sustainable farming systems have focused on the example of organic farming. Formal standards for organic food production, however, do not typically include detailed require- ments for treatment or compensation of the farm labor force (IFOAM, 2002; Guthman, 2004; USDA-AMS, 2009). Some explanations for why organic farms might have progressive farm labor practices and workplace conditions (Duram, 2005) include: organic farmers typically use fewer risky agrichemicals, are more likely to use diversified livestock and cropping systems that are better able to employ labor throughout the year, and might be more likely to share an ideo- logical commitment to environmental and social justice issues (Pretty, 1995; Guthman, 2004; Glenna and Jussaume, 2007). Nevertheless, organic farming systems in the United States have been criticized for relying heavily on mundane hand labor and for exploiting the la- bor of idealistic, young farm interns seeking to learn about farming by working on organic farms for a summer. In addition, the organic and sustainable farming social “movements” have spent much more time advocating for environmental issues than for the well-being and fair treatment of farmers or farm workers (Allen et al., 1991; Allen and Sachs, 1993). Detailed empirical studies of the labor practices on organic and sustainable farms have only recently been conducted. In general, organic production entails greater use of labor per unit output, although there is a greater share of overall farm labor obtained from unpaid family members (Tegegne et al., 2001; Macombe, 2007; MacRae et al., 2007). Although the labor required to produce individual crops using organic techniques might be high, the diverse cropping patterns (and the reintegration of livestock into tradi- tional cropping systems) often associated with organic farming can spread labor demands evenly throughout the year (Nguyen and Haynes, 1995). In some cases, the distribution of labor-input needs over time reduces the need for hired workers or could provide greater opportunities for full-time permanent employment for farm workers. Perceived high labor requirements are often cited as a critical barrier to adopting or- ganic methods by conventional farmers (Schneeberger et al., 2002). But, at the same time, the increased labor associated with alternative farming practices has not diminished the

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 EXAMPLES OF FARMING SYSTEM TYPES FOR IMPROVING SUSTAINABILITY work satisfaction of farmers or the likelihood of farm succession among farmers in France (Macombe, 2007). To some extent, machinery or management techniques can be developed or adapted to reduce labor needs in organic systems to levels similar to conventional prac- tices (Peruzzi et al., 2007); a small fraction of public and private sector agricultural research and development has been conducted with that goal in mind (Dabbert et al., 2004). Because of the large scale and heavy use of labor in Californian agriculture, several recent studies report data on the treatment of hired workers among organic farms in that state. Initially, Guthman (2004) reported that exclusively organic farms tended to pay higher wages to farm workers than farms that maintained both organic and nonorganic operations. However, larger farms of both types tended to pay higher wages and were more likely to offer benefits than small operations. Whether larger farms of either type tend to offer higher wages than their smaller counterparts was unclear. An exploratory survey (Shreck et al., 2006) found that two-thirds of organic farmers in the survey hired workers (other than family members) for at least part of the year, but that just one-third of organic farms provided at least one basic health benefit to their workers. The provision of health insurance benefits was positively correlated with the overall scale of the farming operation. In addition, another study that compared wage and benefit prac- tices of organic and conventional farms in California found that organic farms paid better wages and were more likely to offer profit-sharing (or produce-sharing) arrangements with their workers (Strochlic et al., 2008). However, conventional farms were more likely to offer their workers health insurance, paid time off, retirement plans, and employee manu- als. Fair labor practices are not necessarily a result of organic farming. Whether farmers provide fair wages and good working conditions depends on their commitment to social justice, their perceived financial impacts on the farm as a result of such provision, and other conditions. Food Adequacy As discussed in Chapter 4, food security depends on multiple factors, including poli- cies, prices, and access to food, but the first step is to ensure adequate production. Badgley et al. (2007) compiled data from multiple studies and estimated the global organic food supply by multiplying the amount of food in the 2001 food supply by a ratio comparing average organic to nonorganic yields. The authors suggested that organic farming could produce enough food on a global per capita basis to sustain the current human popula- tion, and potentially an even larger population, without increasing the agricultural land base. Their findings were based on a global dataset of 293 yield ratios for plant and animal production taken from previous studies that compare organic and nonorganic production systems (Badgley et al., 2007) and have been criticized by Cassman (2007). Although 74 percent of the studies used in the Badgley et al. dataset were from peer-reviewed journals (Badgley and Perfecto, 2007), Cassman (2007) stated that many studies “seem to be demon- strations and informal trials” and fail to meet reliable scientific standards. Another criticism is that a portion of their dataset was from Pretty and Hine’s (2000) survey data from 52 de- veloping countries, where many farms included as “organic” were only “close to organic.” Nevertheless, their results, along with the Stanhill study (1990) mentioned earlier, suggest that organic methods of food production can contribute to feeding the current and future human population on the current agricultural land base. Crop yields in organic and nonorganic systems were also discussed earlier in the con- text of farm economics. This committee did not consider whether a certain system type could feed the world because how each system type is managed can affect the farm’s sus-

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