In addition, methyl eugenol, an important compound in fresh flowers that has not been identified in European elder flowers was also present in low quantities , meaning aqueous products that use dry flowers may have a unique aroma profile as compared to the European elder flower that are used in virtually all commercial elder flower products. The elder flower teas evaluated herein were prepared without the addition of added ingredients that are commonly used in the preparation of elder flower syrups, tonics, and beverages. Sugar, lemon, citric acid or vinegar, and preservatives like sodium benzoate are common ingredients used in these products but can impact the headspace VOC profiles. Elderflower syrups are a cooked product, and the time and temperature at which they are processed will influence the headspace VOC profile. Elderflower syrups evaluated via dynamic headspace sampling and GC/MS, show that cis-rose oxide, hotrienol, linalool, -3-hexenol, cis-linalool oxide and trans-rose oxide are some of the predominant volatiles. Of these, the only compound also identified in the present study is -3-hexenol, which was present at 3.51 ± 0.41% in fresh flowers and 18.60 ± 0.67% in dry flowers. Heptanal and nonanal were also identified in the syrup, and levels ranged from 15.5 to 80.7 ng mL-1 and 13.1 to 33.2 ng mL-1 , respectively. These compounds represent < 1-3% of the total concentration of VOCs and are significantly lower as compared with the levels identified in the present study. In another study of elder flower syrup with European elder flowers, a variety of process parameters, vertical plant tower such as extraction temperature, time, and syrup composition, were evaluated for their impacts on VOCs profiles.
While the concentration of volatile compounds was dependent upon how the syrup was made, -rose oxide, linalool, -3-hexen-1-ol, -rose oxide, 1,1,6-trimethyl,1,2-dihydronaphthalene, -linalool oxide, and 2- and 3-methyl-1-butanol were some of the most concentrated compounds identified. In comparison to our results, -3- hexen-1-ol was identified to be the isomer present, and 3-methyl-1-butanol was present in dry ground flowers but only at 3.61 ± 0.13%. Not surprisingly, the volatile profiles from European elder flower syrups do not correspond well with the blue elder flower teas. However, future studies evaluating syrup made from blue elder flowers, could provide better insight into how the aroma, flavor and biological potential differs from syrups made from European subspecies. Studies could also include the American elder flower, which has not been evaluated for its headspace VOC profile before and results could further differentiate these subspecies. The results from this study present the first information on the phenolic and VOC composition of the blue elder flower, the subspecies native to the western region of North America. The phenolic profile elucidated unique characteristics of this subspecies compared to the other more widely used subspecies, S. nigra ssp. nigra and S. nigra ssp. canadensis, namely that IR was the predominant phenolic compound measured. A novel phenolic compound, 5-hydroxypyrogallol hexoside, was also identified in the blue elder flowers. Furthermore, the headspace VOC profile of the fresh and dry flowers as well as teas made from both types of flowers showed distinctive aroma profiles, highlighting that how elder flowers are processed post-harvest will impact the volatile compounds present and their relative concentration. Methyl eugenol and 5-HPG hexoside were identified for the first time in elder flowers. Further sensory evaluation would help determine if consumers differentiate between products using various subspecies of elder flower.
In-person interviews were conducted in the winter, between December 2019 – February 2020; three interviews were conducted in December 2020. We used a two-tiered interview process, where we scheduled an initial field visit and then returned for an in-depth, semi-structured interview. The purpose of the preliminary field visit was to help establish rapport and increase the amount and depth of knowledge farmers shared during the semi-structured interviews. The initial field visit typically lasted one hour and was completed with all thirteen participants. Farmers were asked to walk through their farm and talk more generally about their fields, their management practices, and their understanding of the term “soil health.” The field interview also provided an opportunity for open dialogue with farmers regarding management practices and local knowledge . Because local knowledge is often tacit, the field component was beneficial to connect knowledge shared to specific fields and specific practices. After the initial field visits, all 13 farmers were contacted to participate in a follow up visit to their farm that consisted of a semi-structured interview followed by a brief survey. The semistructured interview is the most standard technique for gathering local knowledge . These in-depth interviews allowed us to ask the same questions of each farmer so that comparisons between interviews could be made. To develop interview questions for the semistructured interviews , we established initial topics such as the farmer’s background, farm history, general farm management and soil management approaches. We consulted with two organic farmers to develop final interview questions. The final format of the semi-structured interviews was designed to encourage deep knowledge sharing. For example, the interview questions were structured such that questions revisited topics to allow interviewees to expand on and deepen their answer with each subsequent version of the question. Certain questions attempted to understand farmer perspectives from multiple angles and avoided scientific jargon or frameworks whenever possible. Most questions promoted open-ended responses to elicit the full range of possible responses from farmers. In the interviews, we posed questions about the history and background of the participant and their farm operation, how participants learned to farm, and to describe this process of learning in their own words, as well as details about their general management approaches.
Farmers were encouraged to share specific stories and observations that related to specific questions. Next, we asked a detailed set of questions about their soil management practices, including specific questions about soil quality and soil fertility on their farm. In this context, soil quality focused on ecological aspects of their soil’s ability to perform key functions for their farm operation ; while soil fertility centered on agronomic aspects of their soils’ ability to sustain nutrients necessary for production agriculture . A brief in-person survey that asked a few demographic questions was administered at the end of the semi-structured interviews. Interviews were conducted in person on farms to ensure consistency and to help put farmers at ease. The interviews typically lasted two hours and were recorded with permission from the interviewee. Interviews were transcribed, reviewed for accuracy, and uploaded to NVivo 12, a software tool used to categorize and organize themes systematically based on research questions . Coding is a commonly used qualitative analysis technique that allows researchers to explore, understand, and compare interviews by tracking specific themes . Through structured analysis of the interview transcripts, we identified key themes and constructed a codebook to delineate categories of knowledge. Once initial coding was complete, growing strawberries vertically we reviewed quotations related to each code to assess whether the code was accurate. The final analysis included both quantitative and qualitative assessments of the coded entries. For the quantitative measure, we tallied both the number of coded passages regarding different themes or topics, and the number of farmers who addressed each theme. In addition, we examined the content of the individual coded entries to understand the nature of farmer knowledge and consensus or divergence among farmer responses for each theme.The following results represent the collective pool of knowledge from the organic farmers involved in this study, based on their responses to interview questions. Consequently, these results only identify and characterize general types of knowledge that these 13 farmers shared during interviews but does not fully encompass all types of knowledge that these particular farmers possess. Most importantly, these farmers are not necessarily representative of all organic farmers within their region, or beyond. Below, we introduce farmer demographics, situate farmer knowledge in terms of their connection to the land, and provide insight on how farmers accumulate knowledge; finally, we synthesize key themes that emerged from farmer interviews with regards to soil management. The interview pool of 13 organic farmers included 10 men and 3 women between the ages of 45 to 70. Nearly all farmers were white , and nearly all farmers had post secondary education.
In addition, each farmer interviewed was actively managing their farm at the time of the interview and represented the primary decision maker on the farm. Most farmers either grew up on a farm and/or had worked on a farm prior to assuming farm management at their current farm operation. Only three farmers were second generation farmers, and the remainder were first generation farmers. All farmers had been farming for at least a decade, and most farmers had been farming for at least three decades, typically on the same lands. Nearly half of the farmers expressed they were at a big turning point in their personal lives when they decided to farm full time . All farmers interviewed mentioned direct experience as being one of the most important modes for understanding their landscape, their farming system, and management practices essential to their farm operation. Farmers described this accumulation of experience as “learning by doing,” being “self-taught,” or learning by “trial and error” . These farmers added that in learning by experience, they made “a lot of mistakes” and/or faced “many failures” but also learned from these mistakes and failures—and importantly, that this cycle was crucial to their chosen learning process. More than half of the farmers interviewed maintained that no guidebook or manual for farming exists; while reading books was viewed as valuable and worked to enhance learning for individual farmers, to farm required knowledge that could only be gained through experience. Moreover, nearly all farmers also explicitly commented on the fact that they have never stopped learning to farm . Overall, farmers learned primarily through personal experience and over time, making connections and larger conclusions from these experiences. On-farm experimentation was a critical component of knowledge building as well. For these farmers, experimentation consisted of on-farm methodical trials implemented at small scales, most often directly on a small portion of their fields. Experimentation was often incited by observation , a desire to learn, increased alignment with their own ethos, or a need to pivot in order to adapt to external changes. Farmers experimented to test the feasibility of implementing specific incremental changes to their current farming practices before applying these changes across their entire farm. For example, one farmer relied exclusively on trucking in urban green waste compost as part of the farm’s fertility program when she first started farming. However, one year, she decided to allow chickens to roam in a few of the fields; within a few years, those fields were outproducing any other field on farm, in terms of crop yield. She quickly transitioned the entire farm away from importing green waste compost to rotating chickens on a systematic schedule throughout all fields on her farm. This form of experimentation allowed this farmer to move from relying on external inputs for fertility to cycling existing resources within the farm and creating an internally regulated farming system . For this farmer, this small experiment was monumental and shifted her entire farm towards a management system that was more in alignment with her personal farming ethos. As she described, “When you look at everything on the farm from a communal perspective and apply that concept of community to everything on the farm… it literally applies to every aspect of your life too.”Though this farmer had initially used direct observation to implement raised beds on his farm, as he learned the purpose of raised beds through his own direct experience, he slowly realized—over the course of decades—that raised beds served no purpose for his application. One year, he decided not to shape some of his beds. At the end of the season, he evaluated no real impact on his ability to cultivate or irrigate the row crops on flat ground, and no impact on yield or crop health. In fact, he observed less soil compaction and more aeration due to fewer passes with heavy machinery; and, he saved time and fuel. The transition to farm on flat ground took several seasons for this farmer, but over time, his entire farm operation no longer used raised beds to grow row crops. This breakthrough in farming was informed by personal experience and guided by careful experimentation.