In many developed countries agriculture is undergoing significant changes. Traditional commodity markets are increasingly being supplemented or even displaced by niche markets served by firms producing specialty products. The purpose of this paper is to determine why firms seek out niche markets and what contributes to their success. This paper investigates the characteristics that make niche markets attractive to small and medium-sized agricultural firms and the ways in which these firms become highly adapted for their chosen niche. Results indicate that forming alliances and the development of horizontal and vertical networks are among the most common and most important strategies employed by successful niche marketers. The study found that firms market niche products as part of a portfolio of products that often includes an anchoring commodity. Results also suggest that aggressive growth and pricing strategies may negatively impact a firm's ability to sustain barriers to entry. The development of a niche positioning strategy is often the outcome of a reaction to an existing situation rather than of a priori strategic planning.

In 2014, Khan et al. presented evidence that soil exchangeable K (Exch-K) increases over time without addition of potassium (K) to the soil despite the removal of K in crops on a soil rich in montmorillonite and illite. The authors term this behavior ‘The potassium paradox’. From their review of the literature, the authors also report a lack of crop response to potassium chloride (KCl) fertilization. Close evaluation of these findings reveals that their observations can be interpreted and predicted using current knowledge of K in soil chemistry and its uptake by plants, and there is no paradox in K behavior in the soil–plant system. There is also no evidence of a detrimental effect of KCl on crop yield or quality. Their conclusion that the widely used Exch-K soil test is inadequate for managing K fertilization is discussed and some possible modifications to improve its performance are included. We believe that measurement of Exch-K is an essential and valuable tool and its use should be continued, along with improvements in recommending K fertilizer application.

For many years, crop potassium (K) availability has been estimated by soil testing the plow layer for exchangeable K, in conjunction with potassium chloride fertilization widely promoted as an essential prerequisite for ensuring crop yield and quality. As rigorously documented in our paper, both components of chemical-based K management are seriously flawed by the lack of a scientific basis. Under the pretext of providing economic benefit for the producer and a healthy food supply for the public at large, the real purpose is to generate revenue for the fertilizer industry.

As the finishing touches go on this themed issue, evidence of widespread enthusiasm for urban farming is apparent in many developed countries. Farming in the city, commonly referred to as urban agriculture, has been put forth as a solution to multiple social problems, including the provision of new green spaces, control of runoff and provision of shade that offsets the heat of the concrete city. In cities with abundant vacant land and abandoned plots, urban agriculture promises a reduction of urban blight.

The interest of organic farmers in adopting conservation agriculture principles, including minimal soil disturbance, permanent soil cover and crop rotation has been growing since the early 2000s. However, currently there is no network for organic farmers practicing conservation agriculture, and a lack of knowledge on how organic farmers implement conservation agriculture in practice. Consequently, few technical references are available for organic farmers when they start applying conservation agriculture practices, in particular on controlling weeds without the use of herbicides. The main objectives of this study were: (1) to explore the diversity of conservation agriculture techniques (i.e., reduced tillage, no-tillage and green manures) practiced among European farmers, and (2) to identify farmers’ main strategies for implementing conservation agriculture and the agronomic and environmental factors that determine these strategies. Strategies were identified by analyzing survey results on: (1) the type and degree of use of conservation agriculture practices by farmers, and (2) the effects it produces in terms of soil disturbance and soil cover (low, medium and high). We carried out a survey of 159 European organic farmers and collected 125 data sets on management of winter-sown crops. Among the conservation agriculture practices, reduced tillage was used by 89%, no-tillage by 27% and green manure by 74% of the 159 interviewed farmers. Green manures were more frequently used in northern Europe than in the south (below 45°N). Most of the farmers used crop rotations, with a mean duration of 6 years. A wide diversity of conservation agriculture practices were used, with farmers rarely using all three techniques (no-till, reduced till and green manures) within one system. The range of practices was grouped into five strategies ranging from intensive non-inversion tillage without soil cover to very innovative techniques with no-tillage and intercrops. The five strategies for conservation agriculture could be grouped into two larger categories based on weed control approach: (1) intensification of the mechanical work without soil inversion or (2) biological regulation of weeds with cover crops. The diversity of strategies identified in this study shows that organic farmers use innovative approaches to implement conservation agriculture without herbicides. This study's findings will help organic farmers to experiment with innovative practices based on conservation agriculture principles and also benefit conventional farmers who use conservation agriculture practices and would like to reduce or eliminate the use of herbicides.

Local food purchasing programs at institutions such as K-12 schools, colleges and hospitals offer benefits including supporting farms and local economies, encouraging more healthful eating habits of patrons and fostering closer connections between farmers and consumers. Increasing in number and expanding in breadth, Farm to Institution (FTI) markets are promising outlets that may fulfill social and economic motivations for farmers. However, significant challenges and barriers have kept many from participating; farmers interested in this market will incur transaction costs, with high negotiation costs in particular due to product differentiation (in this case, by provenance) and less established markets and terms. Researchers have just begun to study farmers’ perspectives on FTI and, to date, have primarily done so through convenience sampling. By utilizing a representative farmer sample, this study provides a major contribution to FTI research. This survey study was designed to better understand Michigan vegetable farmers’ interest and willingness to participate in institutional markets and to identify perceived barriers and opportunities. Michigan is an ideal location for this research as it boasts one of the most diverse sets of agricultural crops in the US, has an economy highly reliant on the food and agriculture industry and has thriving FTI activity with extensive, ongoing outreach, education and research. Results of this survey study showed that half (50%) of the respondents (n = 311) reported interest in selling to at least one institution type (of K-12 schools, colleges and hospitals), but only a small percentage (7%) had yet sold produce to institutions. The most frequently reported motivators to sell to institutions were supplying healthy foods to customers (77%), fair, steady prices (77%) and supplying local food to consumers (76%), indicating that farmers’ motivations are largely based in social values. Smaller scale farmers (less than 25 acres) were significantly less likely to rate economic factors and help in meeting logistical challenges as important, which suggests that they see more potential social value in FTI markets while larger farmers will seek to minimize their transaction costs related to this market. This research can inform the development of scale-appropriate farmer education to foster this market opportunity and its contribution to regional food system development. As demand for local food increases, it is critical to further examine the viability of FTI markets and continue to understand the opportunities and challenges to farmers of different types and scales to participate.

Through the process of globalization, food has experienced an intense territorial restructuring process. Local agric-food links have weakened at the same time as daily products arrived from distant lands. There is presently a wide international debate on the importance of transport in the configuration of the agric-food system and its contribution in terms of greenhouse gas (GHG). The direct environmental costs of the transport of imported food, that is the ‘external food miles’, have been estimated in kilometer (km), ton (t), ton-kilometer (t-km) and GHG in Spain between 1995 and 2011. The analysis is made by ten food groups including 136 products, with special attention to the most important ones (cereals and animal feed), as well as by means of transport (air, rail, road and water) and from 113 different countries belonging to six geographical areas. Two phases are identified during this period: an expansive phase (1995–2007), in which the t-km of imported food increased from 81.8 to 147.8 million t-km and environmental pressure rose from 3.1 to 5.4 million CO2-eq t, and a recession phase (2007–2011), in which environmental pressure subsided as a consequence of the reduction of imports, even though it still remained above the 1995 level. The article reveals a clear interrelation between amounts, distances and modal distribution when it comes to determining the environmental cost of transporting food imports in the two periods studied. It also reflects on the role of the external food miles in the Spanish agri-food system from a sustainability perspective.

In Tanzania, as in many developing countries, cotton is an important source of income for smallholder farmers but also causes various negative effects through high pesticide and intensive land use. To overcome these effects organic agriculture is promoted by different non-governmental organizations (NGOs) and companies. This study examines how organic cotton cultivation influences the livelihood of smallholder farmers in rural Tanzania and focuses on three areas: (1) the motivation to change from conventional to organic farming, (2) experiences and challenges of farmers in the conversion process as well as in the period following the conversion, and (3) the attitude and perceptions of farmers toward organic farming in general. Qualitative interviews with organic farmers in Meatu district in the north of Tanzania, as well as expert interviews, were conducted and observations were made. Results show that although the organic price premium is an important incentive for farmers to convert to organic agriculture, access to training and advisory service are even more important, as no other sufficient agriculture extension service is available in the region. Due to a high level of poverty in the region, environmental motivations for conversion are not in the foreground. Furthermore, the study shows that organic farming can contribute greatly to the improvement of livelihoods in the region (improved soil fertility, increased yields and income, higher standard of living) and increases farmers’ ability to cope with challenges, mainly through knowledge transfer, access to capital and capacity building on a local level. Although positive effects on female farmers were identified, cultural preconditions (e.g., polygamy) harm efforts to strengthen women to a higher degree and gender disparities are still challenging. Further social problems (i.e., high birth rates, a poor education system and a lack of health care), global trading schemes as well as environmental factors (i.e., water scarcity and extreme weather events) cannot be fully offset by the conversion to organic cotton cultivation. Farmers in the Meatu region profit to a high degree from organic agriculture, mainly due to access to knowledge and extension services, nevertheless important challenges remain for farmers and their families.

Localization is one process/outcome that is proffered as key to the ‘grand challenges’ that currently face the food system. Consumers are attributed much agency in this potential transformation, being encouraged from all levels of society to exert their consumer muscle by buying local food. However, due to the social construction of scale it cannot be said that ‘local food’ is a definite entity and consumers understand the term ‘local food’ differently depending on their geographic and social context. As such, the research upon which this paper is based aimed to provide a nuanced understanding of how consumers in the particular spatial and social contexts of urban and rural Ireland understood the concept of ‘local food’. A specific objective was to test the theory that these consumers may have fallen into the ‘local trap’ by unquestioningly associating food from a spatially proximate place with positive characteristics. A three-phase mixed methodology was undertaken with a sample of consumers dwelling in urban and rural areas in both Dublin and Galway, Ireland: 1000 householders were surveyed; 6 focus group discussions took place; and 28 semi-structured interviews were carried out. The results presented in this paper indicate that for most participants in this study, spatial proximity is the main parameter against which the ‘localness’ of food is measured. Also, it was found that participants held multiple meanings of local food and there was a degree of fluidity in their understandings of the term. The results from the case study regions highlight how participants’ understandings of local food changed depending on the food in question and its availability. However, the paper also indicates that as consumers move from one place to another, the meaning of local food becomes highly elastic. The meaning is stretched or contracted according to the perceived availability of food, greater or lesser connections to the local producer community and the relative geographic size of participants’ locations. Our analysis of findings from all three phases of this research revealed a difference in understandings of local food among participants resident in urban and rural areas: participants dwelling in rural areas were more likely than those in urban areas to define local food according to narrower spatial limits. The paper concludes with an overview of the practical and theoretical significance of these results in addressing the current dearth of research exploring the meaning of local food for consumers and suggests avenues for future research.

There is a need to design intensive cropping systems that can reap multiple benefits from annual forages including animal feed, soil fertility and weed control. Considering pea/oat (Pisum sativum cv. 40–10/Avena sativa cv. Legget) as a standard green manure, this study investigated the productivity, weed competitiveness, utilization and nitrogen (N) benefit from grazed and ungrazed green manures to spring wheat (Triticum aestivum cv. Waskada) and fall rye (Secale cereale cv. Hazlet). A set of 3-year experiments was carried out in Carman, Manitoba, Canada in 2009, and was repeated in 2010 and 2011. Green manures were grazed by 2–3 ewes and 2–5 lambs for 24 h (1111–1667 sheep days per ha). Averaged over experiments pea/oat mix, hairy vetch (Vicia villosa L.) and sweetclover (Melilotus officinalis cv. Norgold) above-ground dry matter (DM) production were 5036, 5032 and 4064 kg ha−1, respectively. Lentil (Lens culinaris cv. Indianhead), a mixture of seven species and soybean (Glycine max cv. Prudence) produced the least amount of DM over 3 years; 3589, 3551, 3174 kg ha−1, respectively. Pea/oat and hairy vetch were the most weed-competitive species and, averaged over 3 years, contained less than 15% weed DM. Utilization of green manures by grazing animals varied little among species across years and ranged from 28 to 86% for individual species and years. When combined across experiments grazing increased N availability to the wheat crop. The grazing effect was significant for wheat DM production, N uptake and grain N, but not significant for yield across experiments. Averaged over 3 years, wheat took up 107 kg N ha−1 from grazed plots versus 98 kg N ha−1 from ungrazed plots. A significant species×management interaction for total (wheat+fall rye) N uptake in 2009 indicated that increasing the proportion of legumes in the green manure increased N benefit from grazing. Fall rye productivity was not affected by grazing. We recommend pea/oat and hairy vetch as two green manure species to enhance the overall system performance to achieve high level of DM production, good weed competition, utilization by sheep and provision of N benefit to the following wheat and fall rye crops.

Farmers are innovators and experimenters and not just adopters of introduced technologies. The innovations developed by farmers could complement the highly promoted externally driven technologies in addressing the numerous challenges facing agriculture. The aim of this paper was to identify outstanding innovations developed by smallholder farmers in northern Ghana, and prioritize the high potential ones for further scientific validation or dissemination. Using an innovation contest that rewards farmers' creativity, we identified 29 promising innovations. Additionally, 19 innovations were scouted through a household survey. The innovations are largely extensive modifications of existing practices or combinations of different known practices in unique ways to save costs or to address crop and livestock production constraints. While some of the identified innovations can be recommended or disseminated to other farmers, most of them may require further validation or research. However, validating all of these innovations will be very expensive and time-consuming. We propose the multi-criteria decision-making analysis (MCDM) as a simple method to prioritize farmers' innovations. Using this method, we find that among the most promising innovations are those involving the control of weeds, pests and diseases using plant residues and extracts, and the treatment of livestock diseases using ethnoveterinary medicines. We briefly explain the six most highly ranked innovations. This case study from northern Ghana provides further proof that smallholder farmers develop diverse and spectacular innovations to address the myriad challenges they face, and these need to be recognized and promoted. We also conclude that contest and MCDM are useful methods that can be applied in unearthing and prioritizing farmer innovations, respectively.

The environmental benefits of cover cropping are widely recognized but there is a general consensus that adoption levels are still quite low among US farmers. A survey was developed and distributed to more than 200 farmers engaged in two sustainable farming organizations in NC and the surrounding region to determine their level of utilization, current practices and perceptions related to cover cropping. The majority of farms surveyed had diverse crop production, production areas <8 ha, and total gross farm incomes <US$50,000. Approximately one-third of the survey population had an organic production component. Eighty-nine percent of participants had a crop rotation plan and 79% of the total survey population utilized cover cropping. More than 25 different cool- and warm-season cover crops were reported. The statements that generated the strongest agreement about cover crop benefits were that cover crops: increase soil organic matter, decrease soil erosion, increase soil moisture, contribute nitrogen to subsequent cash crops, suppress weeds, provide beneficial insect habitat and break hard pans with their roots. Economic costs associated with cover cropping were not viewed as an obstacle to implementation. A factor analysis was conducted to identify underlying themes from a series of positive and negative statements about cover crops. Pre- and post-management challenges were able to explain the most variability (30%) among participant responses. Overall, participants indicated that the incorporation of residues was their greatest challenge and that a lack of equipment, especially for no-till systems, influenced their decisions about cover cropping. Farmers did not always appear to implement practices that would maximize potential benefits from cover crops.

Sainfoin (Onobrychis viciifolia) is a tanniniferous legume that has been used as non-bloating forage for horses and ruminants for centuries, but so far its protein-rich seeds have not been utilized as a feedstuff for monogastric animals. In Europe, the main protein sources in diets for organic pigs are the grain legumes faba beans (Vicia faba) and peas (Pisum sativum), alongside the expensive high-quality components soybean cake, skimmed milk powder and potato protein. Because of the scarce supply of organic soybean cake and the highly variable yield of peas, alternative and locally produced protein sources are of great interest. As part of the EU Core Organic II research project ICOPP (improved contribution of local feed to support 100% organic feed supply to pigs and poultry), sainfoin seeds have been tested as a protein source for organic weaned piglets. In a feeding trial, a control diet, one diet containing 10% sainfoin seeds with hulls and two diets with 10 and 16% dehulled seeds, respectively (as fed basis) were fed to 137 piglets (crosses of [Pietrain×Duroc]×[Landrace×Large White]) during the 4-week post-weaning phase. The protein-rich components of the control diet were peas and soybean cake, which were partly substituted for sainfoin seeds in the experimental diets. Sainfoin seeds were found to contain 279 g kg−1 crude protein (388 g kg−1 when dehulled, as fed basis) with an amino acid profile suitable for pig feeding. Neither feed intake and body weight gain nor feed conversion ratio differed between treatments. It is concluded that sainfoin seeds can be a valuable protein source in moderate percentages of 10–16% in organic diets for weaned piglets. Where sainfoin can be cultivated easily and the seeds are harvested, using them as feed for piglets can therefore be recommended.

Rotational grazing (RG) is a livestock management practice that rotates grazing cattle on a scale of hours to days among small pastures termed paddocks. It may beneficially affect stream channels, relative to other livestock management practices. Such effects and other beneficial effects on hydrology are important to RG's potential to provide a highly multifunctional mode of livestock farming. Previous comparisons of effects of RG and confinement dairy (CD) on adjoining streams have been restricted in scale and scope. We examined 11 stream-channel characteristics on a representative sample of 37 small dairy farms that used either RG or CD production methods. Our objectives were: (1) to compare channel characteristics on RG and CD farms, as these production methods are implemented in practice, in New York, Pennsylvania and Wisconsin, USA; and (2) to examine land use on these farms that may affect stream-channel characteristics. To help interpret channel characteristic findings, we examined on-farm land use in riparian areas 50 m in width along both sides of stream reaches and whole-farm land use. In all states, stream-channel characteristics on RG and CD farms did not differ. Whole-farm land use differed significantly between farm types; CD farms allocated more land to annual row crops, whereas RG farms allocated more land to pasture and grassland. However, land cover in 50 m riparian areas was not different between farm types within states; in particular, many RG and CD farms had continuously grazed pastures in riparian areas, typically occupied by juvenile and non-lactating cows, which may have contributed sediment and nutrients to streams. This similarity in riparian management practices may explain the observed similarity of farm types with respect to stream-channel characteristics. To realize the potential benefits of RG on streams, best management practices that affect stream-channel characteristics, such as protection of riparian areas, may improve aggregate effects of RG on stream quality and also enhance other environment, economic and social benefits of RG.

Changes in methanogenic archaea were investigated in pilot-scale experiments during one- and two-stage mesophilic anaerobic digestion (AD) of food waste. Methane yields were 379.7±75.3 liters of methane per kg of volatile solids [L-CH4 (kg-VS)−1] added to the system, during one-stage operation, and 446±922 L-CH4 (kg-VS)−1 added during two-stage operation. Populations of methanogenic archaea were monitored quantitatively by targeting the functional gene for methyl-coenzyme-M reductase (mcrA) using real-time quantitative polymerase chain reaction techniques. During one-stage operation, mean mcrA gene concentrations were 2.48×109±2.7×109 copies ml−1. Two-stage operation yielded mean mcrA gene concentrations of 9.85×108±8.2×108 copies ml−1 in the fermentation and 1.76×1010±8.5×109 copies ml−1 in the methanogenesis reactors, respectively. Diversity of archaea in the methanogenic reactors was investigated by denaturing gradient gel electrophoresis targeting the V3 region of 16S rRNA of archaea. The Shannon index (H) was 2.98 for one-stage operation and 7.29 for two-stage operation, suggesting greater archaeal diversity in the two-stage AD. The fivefold increase in methanogenic archaea populations during the two-stage operation, as indicated by mcrA gene concentration, corresponded to an increase in methane production rates. While the diversity may also be related to the stability of the microbial bioprocesses and improved methane production rates, the correlation between diversity and production rates should be studied further.

Agriculture must face a number of very pressing environmental issues. We used the prototyping method to design three innovative cropping systems, each satisfying three ambitious goals simultaneously: (1) overcoming a major environmental constraint, which represents a major break regarding objectives to be reached in current cropping systems (differing between systems: a ban on all pesticides but with chemical nitrogen (N) fertilizer permitted; reducing fossil energy consumption by 50%; or decreasing greenhouse gas (GHG) emissions by 50%), (2) meeting a wide range of environmental criteria and (3) maximizing yields, given the major constraint and environmental targets. A fourth cropping system was designed, in which the environmental and yield targets were achieved with no major constraint (the productive high environmental performance cropping system (PHEP) system). The performances of these innovative cropping systems were compared to a conventional system in the Ile-de-France region. We used a three-step prototyping method: (1) new cropping systems were designed on the basis of scientific and expert knowledge, (2) these system prototypes were assessed with tools and a model (ex ante assessment) adjusted to the set of constraints and targets, with optimization by an iterative process until the criteria were satisfied and (3) evaluation in a long-term field experiment (ex post assessment), which is currently underway. We describe only the first two steps here, together with the results of the prototypes assessment with tools and a model. The pesticide, energy and GHG constraints were fulfilled. All these innovative systems satisfied environmental criteria in terms of nitrogen and phosphorus management, pesticide use, energy consumption and crop diversity. For the pesticide-free system, the soil organic matter indicator was lower than expected due to frequent plowing (every 2 years) and yields were 20–50% lower than for the PHEP system, depending on the crop considered. We focus our discussions on the design methodology and the availability of scientific knowledge and tools for projects of this type.

Organic no-till (NT) management strategies generally employ high-residue cover crops that act as weed-suppressing mulch. In temperate, humid regions such as the mid-Atlantic USA, high-residue winter cover crops can hinder early spring field work and immobilize nutrients for cash crops. This makes the integration of cover crops into rotations difficult for farmers, who traditionally rely on tillage to prepare seedbeds for early spring vegetables. Our objectives were to address two separate but related goals of reducing tillage and integrating winter cover crops into early spring vegetable rotations by investigating the feasibility of NT seeding spinach (Spinacia oleracea L.), an early spring vegetable, into winterkilled cover crops. We conducted a four site-year field study in the Piedmont and Coastal Plain regions of Maryland, USA, comparing seedbed conditions and spinach performance after forage radish (FR) (Raphanus sativus L.), a low-residue, winterkilled cover crop, spring oat (Avena sativa L.), the traditional winterkilled cover crop in the area, a mixture of radish and oat, and a no cover crop (NC) treatment. NT seeded spinach after FR had higher yields than all other cover crop and tillage treatments in one site year and was equal to the highest yielding treatments in two site years. Yield for NT spinach after FR was as high as 19 Mg ha−1 fresh weight, whereas the highest yield for spinach seeded into a rototilled seedbed after NC was 10 Mg ha−1. NT seeding spring spinach after a winterkilled radish cover crop is feasible and provides an alternative to both high-residue cover crops and spring tillage.