Assessing the impact of the EQIP High Tunnel Initiative

This study evaluated the U.S. Department of Agriculture Natural Resources Conservation Service (USDA NRCS) Seasonal High Tunnel Initiative, or HTI, that the USDA expects to strengthen local and regional food production by increasing the availability of fresh, locally grown food. Goals of the HTI include improved plant and soil quality, reduced nutrient and pesticide runoff, and increased availability of fresh vegetables and fruits for local food markets. This study explored the farm-level impacts of production via high tunnels among Indiana farmers relying on the infrastructure. We identify characteristics of farmers who have obtained high tunnels through the cost-share program, to better understand the types of farm enterprises that are using the HTI to date and the effects that high tunnel implementation may have on their farms’ economic success and contributions to locally sourced food systems. Overall, results indicate that high tunnel users are able to extend the growing season, improve their a * Corresponding author: Analena B. Bruce, Postdoctoral Research Fellow, Department of Recreation, Park, and Tourism Studies, School of Public Health–Bloomington, Indiana University; 521 North Park Avenue; Bloomington, Indiana 47405 USA; anabruce@indiana.edu b James R. Farmer, Assistant Professor, Department of Recreation, Park, and Tourism Studies, School of Public Health–Bloomington, Indiana University; 521 North Park Avenue; Bloomington, Indiana 47405 USA; jafarmer@indiana.edu c Elizabeth T. Maynard, Extension Specialist and Clinical Engagement Assistant Professor, Department of Horticulture and Landscape Architecture, Purdue University; P.O. Box 1759; Valparaiso, Indiana 46384-1759 USA; emaynard@purdue.edu d Julia C. D. Valliant, Postdoctoral Research Fellow, The Ostrom Workshop in Political Theory and Policy Analysis, Indiana University; 521 North Park Avenue; Bloomington, Indiana 47405 USA; jdv@indiana.edu

and soil quality, reduced nutrient and pesticide runoff, and increased availability of fresh vegetables and fruits for local food markets.This study explored the farm-level impacts of production via high tunnels among Indiana farmers relying on the infrastructure.We identify characteristics of farmers who have obtained high tunnels through the cost-share program, to better understand the types of farm enterprises that are using the HTI to date and the effects that high tunnel implementation may have on their farms' economic success and contributions to locally sourced food systems.Overall, results indicate that high tunnel users are able to extend the growing season, improve their

Introduction
High tunnels, or hoophouses, are plastic-covered, greenhouse-like structures for growing plants that are typically built directly over the soil to control the growing environment inside (Carey, Jett, Lamont, Nennich, Orzolek, & Williams, 2009).The low-cost structures are heated by passive solar energy and create favorable growing conditions for plants by protecting them from wind, rain, birds, and temperature extremes (Blomgren & Frisch, 2007;Conner, Montri, Montri, & Hamm, 2009).Growers can extend the growing season with a high tunnel, leading to earlier, later, and more frequent harvests, thereby producing more fresh produce year-round (Lamont, 2009).Increasing the availability of fresh produce, both in terms of adequate volume during the growing season, and supply during the fall and winter months in colder climates, can address a significant barrier to the further development of community food systems that are limited by low supply during the colder months (Martinez, 2010).
High tunnels may be particularly well suited to small-scale, diversified farms that sell their products into local food systems (Cole, n.d.).Research trials have demonstrated that the use of high tunnels makes it possible for farmers to increase the quality and yield of specialty crops, and to reduce the risk of weather-related crop damage and loss (Belasco, Galinato, Marsh, Miles, & Wallace, 2013;Knewtson, Carey, & Kirkham, 2010;Lamont, 2009).By extending their growing season, small farms can capture more revenue and retain their customer base for more months of the year (Martinez, 2010;Matts, Conner, Fisher, Tyler, & Hamm, 2015).Because they are relatively inexpensive investments that facilitate the intensification of production on small plots of land, high tunnels also offer opportunities for beginning and low-income farmers, and those with a small land base (Conner, Waldman, Montri, Hamm, & Biernbaum, 2010;Waldman, Conner, Biernbaum, Hamm, & Montri, 2012).In addition, high tunnels work particularly well for urban-agriculture initiatives because they help producers maximize production in small spaces (Broadway, 2009;Colasanti & Hamm, 2010;Huff, 2015).
The Seasonal High Tunnel Initiative (HTI) was piloted in 2009 as part of the Know Your Farmer, Know Your Food initiative, which brings together staff from across the USDA to coordinate, share resources, and publicize USDA efforts related to local and regional food systems (Farm News, 2009;USDA, n.d.;USDA NRCS, 2011).Broad goals of the initiative are to support diversified farmers and ranchers, as well as businesses involved in regional food networks, to strengthen the connection between farmers and consumers to reinvigorate rural economies, promote job growth, and increase access to healthy food in America (USDA, n.d.).Thus, from its inception, the HTI was aimed at small-scale, diversified farms that sell directly to consumers through local food systems.The HTI is funded through the Natural Resources Conservation Service's (NRCS) Environmental Quality Incentives Program (EQIP) and offers a cost-share incentive of up to 90% to farmers interested in constructing a new high tunnel.The NRCS's goals for the HTI include (1) improved plant and soil quality, (2) reduced off-site movement of nutrients and pesticides, (3) improved air quality through reduced transportation from farm to market, and (4) reduced energy use through local consumption (USDA NRCS, 2015).Farmers are investing in high tunnels to improve the viability of their farms through increased and extended productivity, diversified growing systems, and reduced risk of crop damage and loss (Belasco et al., 2013).
This exploratory study provides an analysis of the benefits of growing with high tunnels in general and the effects of the cost-share incentive provided by EQIP for use by policy-makers, key stakeholders, and farmers.We identify the characteristics of the farmers who have obtained high tunnels through the cost-share program to better understand the types of farm enterprises that are have used the EQIP to date, and the effects that implementing high tunnels may have on farms' economic success and contributions to locally sourced food systems.Through a survey of farmers using high tunnels in the state of Indiana, we address the following questions: 1. What is the overall impact of using high tunnels in terms of crop yields, crop quality, farm profit, and farmers' quality of life? 2. Do farmers who obtained their high tunnels with support from EQIP differ from those who purchased some or all of their tunnels without support from the EQIP program?
To understand any differences among high tunnel users, we differentiate between those who only have EQIP-funded high tunnels and those who have self-funded one or more of their farm's high tunnels.Analyzing the outcomes of the first five years of the program, this study is the first to provide an understanding of the effects of the HTI from a whole-farm perspective.

Literature Review
Increasing the adoption of season-extension technology is important for addressing a key barrier in the supply chain to developing more robust local and regional food systems in the many parts of the U.S. with a limited growing season (Conner et al., 2009;Mount, 2012).According to former USDA Deputy Secretary Kathleen Merrigan, "high tunnels create favorable conditions enabling farmers to grow vegetables, berries, and other specialty crops in climates and at times of the year in which it would otherwise be impossible…Farmers who sell their high tunnel produce locally benefit from the extra income, and the community benefits from the availability of fresh, locally grown food" (USDA NRCS, 2011, para.1).Consumers at three Michigan farmers markets indicated that they were willing to pay a price premium for early-or lateseason salad greens, spinach, and tomatoes; for example, they were willing to pay up to US$3.00 extra per head of lettuce in the winter season (Conner et al., 2009).A policy report identified high tunnels as a critical infrastructure gap for increasing the distribution of specialty crops in Indiana (Meter, 2012).
Growing in high tunnels also offers the potential for improving the productivity and viability of the small-scale, diversified farms that produce food for local food systems.An informal survey of state extension vegetable specialists indicated that the majority of high tunnel users in the U.S. are beginning farmers operating small-scale, diversified, direct-market operations (Carey et al., 2009).While many benefits of using high tunnels have been identified in research trials, there has not been an adequate study of farmers' lived experiences of integrating high tunnel production into their existing farm systems.A small case study in Michigan found mixed results in terms of farmers' success in increasing their farm's profitability or meeting management goals (Conner et al., 2010;Waldman et al., 2012).In terms of improving profitability and quality of life for farmers, high tunnels were not always used to their full potential (Conner et al., 2010;Waldman et al., 2012).A systematic assessment of the economic impacts, seasonextension potential, and other production benefits at the farm level is needed to fill this gap.
The HTI is designed to provide a streamlined application process and enhanced flexibility to better serve small-scale operations and diversified farm systems (USDA NRCS, 2015).The criteria for HTI cost share eligibility for Indiana farmers is based on the ranking system for the Indiana NRCS specialty-crop program, which ranks each applicant based on their property's conservation activities and their farm's needs (USDA NRCS, 2015).Cost share recipients are required to grow crops directly in the soil in their tunnel (thus aquaponic or greenhouse systems are not allowed), and they must plan supportive conservation practices to address environmental concerns associated with the installation and use of high tunnel systems such as erosion, irrigation, and runoff (USDA NRCS, 2015).
The cost of high tunnel infrastructure varies depending on the size of the tunnel chosen, features and material components selected (basic and upgraded), and construction costs.The average high tunnel costs approximately US$3.25 per square foot (0.09 square meter), or US$7,000 for a 2,160 square foot (201 m²) tunnel (Huff, 2015).However, costs vary by region, with additional reinforcements such as higher gauge hoops and plastic and heavier steel required in northern and eastern regions to withstand harsh winters adding to the overall cost (Huff, 2015).The plastic covering of a high tunnel has an average four to five year lifespan before the plastic must be replaced (Huff, 2015).The Indiana NRCS cost-share funds US$3.85 per square foot, with a maximum payment cap of US$8,385 (USDA NRCS, 2015).
The HTI is part of a suite of programs and incentives designed to meet the needs of populations of farmers who are deemed historically underserved, defined by the USDA as groups that "have not participated in or that in the past have received limited benefits from USDA programs" (USDA NRCS, 2015).The following groups are included in this category: (1) socially disadvantaged farmers and ranchers, (2) beginning farmers and ranchers (defined as those farming fewer than 10 years), and (3) limited-resource farmers and ranchers.For instance, farmers in these categories are eligible for higher cost-share rates of up to 90% and are placed in high-priority funding pools.According to the National Sustainable Agriculture Coalition (NSAC), its analysis of USDA data indicates that the HTI has been strongly utilized by beginning farmers, who made up 51% of program contracts in 2013.Historically underserved producers (in all categories combined) accounted for over 70% of HTI contract holders in 2013, while representing just 26% of participants in EQIP programs in general (NSAC, 2014a(NSAC, , 2014b)).
To our knowledge, the only research to date on the HTI is a study that analyzed the nationwide distribution of NRCS-funded high tunnels in relation to county-level biophysical, market, and sociodemographic data, to understand which factors influence the adoption of high tunnels through the HTI (Foust-Meyer & O'Rourke, 2015).This study found that farmers' geographic location was most correlated with the incidence of NRCS-funded high tunnels.Not surprisingly, farmers located in higher latitudes were more likely to have purchased a high tunnel through the HTI, where farmers most benefit from technologies to extend the growing season.In addition, farmers' proximity to urban areas with higher median household income was related to their participation in the HTI, and female farm operators were proportionately more likely to obtain high tunnels through the HTI.Finally, farmers in or near metropolitan counties with robust local food systems (high direct-toconsumer sales) were most likely to adopt high tunnels through the HTI (Foust-Meyer & O'Rourke, 2015).Our study assesses the farm-level impacts and benefits of using high tunnels and determines whether those impacts differ for farmers who purchased their own tunnels compared to those who obtained their tunnels through the EQIP program.

Methods
This exploratory survey examines the outcomes of participation in NRCS's EQIP HTI and also compares those farms with only EQIP-funded high tunnels to those whose high tunnels are all or in part self-funded.We build on earlier case studies of high tunnel users through a quantitative-focused survey that was mailed to farmers across Indiana, USA (Waldman et al., 2012).

Study Site
While Indiana is known for its commodity agricultural products like corn, soybeans, wheat, pork, and poultry, the state also has specialty crop producers distributing through local food system venues (Meter, 2012).Specialty crops are defined as "fruits and vegetables, tree nuts, dried fruits, horticulture, and nursery crops, including floriculture" (USDA Agricultural Marketing Service, n.d.).In 2012, 2,935 specialty crop farms were operating in Indiana (USDA NASS, 2015), a slight increase from 2,925 in 2007 (USDA NASS, 2007).The Indiana division of the USDA NRCS began administering the EQIP HTI cost-share program to Indiana farmers in 2012, three years after the USDA approved the HTI and other states began to offer the cost-share program.Interest in and demand for the program among the state's farmers have grown since 2012, with over 170 tunnels constructed on farms since its inception.This represents an investment of nearly US$1.5 million in Indiana (A. Heichelbech, personal communication, February 20, 2015).In comparison, over 10,000 farms had installed new high tunnels nationally due to the cost-share program by 2014 (Starmer, 2014).In addition to these investments from the USDA, growers have personally invested significant funds in high tunnels.

Sampling, Instrumentation, and Data Collection Approach
Since there is currently no comprehensive list of high tunnel owners in Indiana, the research team followed a convenience sampling approach, which suffices in exploratory research (Schutt, 2006).Procedures included garnering as much contact information as the Indiana NRCS office could disclose for HTI participants (143 names, with city and county of residence); using online databases (whitepages.comand county GIS platforms) to garner mailing addresses; incorporating respondents who had reported owning a high tunnel in a previous survey administered by our research group (Valliant, Farmer, Dickinson, Bruce, & Robinson, in press); and incorporating names of our research group's personal and professional contacts who have a high tunnel.Additionally, one county extension educator hand-delivered the questionnaire (and return envelopes) to 14 growers who use high tunnels.The unsystematic selection process is a limitation to this study's results.In total, the questionnaire was distributed to 178 farmers (see the instrument in the Appendix).
While the paper instrument was the primary tool for data collection, an electronic option was also made available.Every survey included a US$5 cash incentive to encourage participation (Dillman, Smyth, & Christian, 2008;Singer, 2012).We followed a modified Dillman tailored-design survey method (Dillman et al., 2008) for distributing the questionnaire and collecting responses.The survey was mailed to 164 contacts.The four-phase approach included (1) a postcard announcing the survey soon to follow, (2) the survey one week later, (3) a reminder postcard to nonrespondents two weeks after that, and (4) a follow-up survey mailed to nonrespondents two weeks thereafter.We then followed up with a phone call to nonrespondents in order to evaluate the underlying issues for the nonresponse.
The survey consisted of six sections that solicited data through 38 questions.Section 1 included questions about farm location, number of high tunnels, EQIP-funded high tunnels, and descriptive information on farmers' use of their high tunnel(s).Section 2 was composed of questions concerning growers' perception of the value of the high tunnel for their farm.Section 3 queried farmers about the distribution approaches they utilized.Section 4 asked farmers about the crops they produce in their high tunnels, production issues and challenges, research needs, and common practices they employ.Section 5 asked about farm characteristics and economic issues.Section 6 queried participants for demographic information.

Data Management and Analysis Approach
We input data into an online version of the questionnaire that was built through Qualtrics software.Data were analyzed using SPSS 23.0.Descriptive and cross-tab statistics were used to calculate general results for demographic variables, farm characteristics, distribution type (direct-toconsumer or otherwise), and general mean scores related to Likert-style questions.Based on farmer responses, we created a dichotomous variable to compare farmers that (1) had only EQIP-funded high tunnels (n=47) or (2) had no EQIP-funded or had a combination of EQIP-and self-funded high tunnels (n=56).We used analysis of variance (ANOVA) to compare results related to the continuous variable questions (as well as the Likertstyle responses), and chi-square analysis to explore the differences in categorical variables (e.g., distribution method, gender, and education) between the two groups of farmers.
We also performed a binary logistic regression to compare the two groups (EQIP-only [1] vs. Combo/Self-funded [0]) to define key points of differentiation between the two.The six covariate variables included (1) likelihood of purchasing a future high tunnel without EQIP-funding costshare support, (2) percentage of household income earned through off-farm employment, (3) effect of the high tunnel(s) on improving farm economic stability, (4) educational attainment (bachelor's degree vs. no bachelor's degree), ( 5) their perception of the utility of high tunnels in reducing pest problems, and (6) their perception of the utility of high tunnels in improving harvest quality.

Results
Of the 178 questionnaires distributed, 118 were returned (6 of these were electronic).Nine were returned with insufficient addresses, four responses noted that the high tunnel was not yet erected, one person did not have a high tunnel, and one person declined to participate.One hundred and three questionnaires were deemed usable, and with an adjusted sample of 164, we had a 62.8% response rate.The mean participant age was 36.98, with the vast majority of respondents being the farm owner (92.2%); 27.2% identified as female, and 48.5% of respondents had attained a bachelor's degree or higher education (see Table 1).Most respondents had an annual farm income of less than US$49,999, with nearly 20% making less than US$5,000 from their farms.Most (82.6%) respondents were located in hardiness zone 5, with 17.4% in hardiness zone 6.The average proportion of revenue from specialty crops, when compared to total farm revenue, was 40.8% (median of 26.25%).Table 1 provides further details on the demographic characteristics of respondents, while also differentiating and providing significance indicators for differences between those farmers who have only EQIPfunded high tunnels ("EQIP-only"; 45.6%) and those who have only or in part self-funded high tunnels ("non-EQIP-combo"; 54.4%).
We compared demographic and farm experience variables for the EQIP-only high tunnel users and the non-EQIP-combo group and found several statistically significant differences.The two groups demonstrate differences (p<.05) for gender and age.EQIP users were more likely to be older (5.61 mean years) and female than the farmers who had purchased some or all of their high tunnels themselves.The non-EQIP-combo farmers earned more household income from the farm and had been growing in high tunnels for a longer period of time (p<.01).Last, the EQIP-only farmers were more likely to have a higher educational attainment level.The data also point to significant differences, and some marginal ones, between the two groups, with the EQIP-only farmers earning less in gross specialty crop sales, less in dollars per square foot of high tunnel production, farming fewer acres, having fewer high tunnels, and being less likely to invest their own money in future high tunnel purchases (see Table 2).
We also analyzed 20 variables on the value to a farm's bottom line of producing in high tunnels (see Table 3).This included variables on farm profit, product diversification, production during the shoulder seasons (late fall and early spring), as well as pest and disease issues (see questions 13, 14, and 19 in the Appendix).Of these 20 variables, seven were found to be significantly different between the two groups.Non-EQIP-combo farmers were more likely to indicate in the survey that growing in high tunnels increased overall farm profit, overall yields, the farm's economic stability, allowed the harvesting of warm-season crops earlier in the season, improved the quality of the harvest, and reduced pest problems (vertebrate problems in particular).
Lastly, we used binary regression analysis to answer the following research question: Do farmers who obtained high tunnels only through the HTI differ from farmers who purchased some or all of their tunnels using their own funds or other non-EQIP funds?Our regression model tested the differences between the two groups of farmers (dependent variable) in relation to six variables (see Table 4).This model met statistical parameters (Hosemer Lemeshow score of p=.629) and was statistically significant (p=.000).Three variables were identified as significant, and they were accurate in predicting group placement 68.4% of the time: the likelihood of purchasing another high tunnel without the EQIP cost share, the percentage of income coming from off-farm employment, and improved farm economic stability.First, as the likelihood someone would purchase a future high tunnel without the EQIP cost share increased, the chances of them being an EQIP-only high tunnel user decreased.Second, as the proportion of one's income coming from off-farm employment increased, so did the chances of them being an EQIP-only high tunnel user.Third, as respondents' scores denoting the improved farm economic stability increased, the chances of them being an EQIP-only user decreased.In summary, the EQIP-only high tunnel users depend less on farming operations for household income, are less inclined to purchase a future high tunnel out of pocket, and did not find that high tunnels improved the quality of their harvest as much as the non-EQIP-combo farmers indicated.

Discussion
Overall, the study provides evidence that at least in the state of Indiana, the HTI is enabling farmers to extend the growing season and increase the availability of locally grown food, based on this self-reported questionnaire and those who participated.Specifically, analysis of the results from this survey suggests three salient points.First, high tunnel users across the board (both those solely EQIP-funded and those self-funded or partially self-funded) indicate positive outcomes from growing specialty crops in high tunnels.Second, those farmers with high tunnels funded solely by EQIP earn a smaller percentage of their household income from their farms, compared to those who funded all or a portion of their own high tunnels.
The most striking variable distinguishing solely EQIP-funded and self-funded or partially selffunded farmers is the economic impact of the high tunnel for farm operations.In sum, there are differences between the two groups that indicate that farmers who rely more heavily on their farms for household income and have invested more of their own resources in high tunnels have also experienced the greatest economic benefit from their tunnels.In this section, we discuss the ramifications and implications of these findings.

Overall Outcomes for High Tunnel Users
All high tunnel users in Indiana who responded to the survey (both solely EQIP funded and some/all self-funded) generally reported that growing specialty crops in high tunnels has positive effects on their farms' earnings and their own quality of life.Growers in both groups specifically indicated that growing crops in high tunnels allowed them to increase their overall farm profit and improve the economic stability of their farms.This increased economic stability is likely due to the improvements growers reported with the quality and yield of their crops.In addition, growing with high tunnels enabled them to extend the growing season into the cooler months of the year, thereby earning an income in more months of the year.These findings are important because, as noted by Waldman and colleagues (2012) and based on our review of the literature, there has not been a systematic assessment (beyond case studies) of the economic impact of using high tunnels, or of growers' experiences with high tunnels.Existing evidence for the production benefits of growing specialty crops with high tunnels has been based on crop trials on research farms that may not take into account growers' experiences with integrating high tunnels into routine whole-farm management.Improving farmers' economic stability and increasing their profits is a core goal of the Know Your Farmer Know Your Food initiative, and thus an indication that the program has had a positive impact.

Characteristics of EQIP-funded vs. Self-funded or Partially Self-funded High Tunnel Farmers
Farmers in our sample who only have high tunnels funded by the EQIP program differ from those funding all or a portion of their own high tunnels in a number of respects.They are less dependent on their farm for household income, and mostly manage smaller farms.They earn less income from their specialty crops, less in dollars per square foot of high-tunnel production, and manage fewer high tunnels.They are also less likely to invest their own money in additional high tunnels in the future (see Table 2).The USDA defines farms with a gross cash farm income (GCFI) of US$10,000 or less as noncommercial or lifestyle farms (Hoppe, MacDonald, & Korb, 2010).Farmers in the EQIP-only funded group are typically older, likely reflecting the prevalence of owner-operators managing a lifestyle farm as a second career, hobby, or following retirement (Ahearn & Newton, 2009).It is not surprising that the EQIP-only funded group has a higher percentage of graduate-level education, reflecting the fact that farming may not be their primary career or occupation.These findings are consistent with the results of a previous study suggesting that smallscale specialty-crop farmers who make less than US$10,000 in annual revenue from their farm are most likely to take advantage of the HTI (Foust-Meyer & O'Rourke, 2015).Women make up more of the EQIP-only group, reflecting NSAC's preliminary analysis of national data, showing that female owner-operators have higher participation rates in EQIP programs than they do in other USDA programs (NSAC, 2014).The findings suggest that, overall, the growers who have more "skin in the game," or who have relied on their personal funds to invest in a high tunnel, are more motivated to utilize their high tunnel effectively.In general, these farms are larger with higher gross incomes and thus more capital to invest in high tunnel infrastructure.Likewise, they invest more of their labor in their high tunnel, as they are more reliant on their farm for income than the farmers in the EQIP-only group.

Significance of Years of Farming Experience for Economic Success with High Tunnels
The most striking variables distinguishing solely EQIP-funded and some or all self-funded farmers are the years one has personally farmed using a high tunnel, and the economic impact of the high tunnel for their farm operations.Those farmers who had more experience with high-tunnel production were more likely to have funded at least one of their own tunnels, as opposed to experimenting with a high tunnel for the first time through the EQIP program.This is likely because the use of high tunnels has been increasing in the U.S., and while the cost-share program was approved nationally in 2009, the state of Indiana only implemented the program in 2012.Thus some specialty-crop farmers in Indiana were using high tunnels for years before the program was implemented.As a result, the farmers who had invested in their own tunnels were able to use the EQIP program to add additional tunnels to their operation, thus expanding their high-tunnel production.
Given that the self-funded or partially selffunded farmers had gained experience with high tunnel production prior to the EQIP program, it is not surprising that they reported better economic gains from their tunnels than their less-experienced counterparts.Likewise, the EQIP-only group reported less success with improving the quality of their harvested products with high tunnels, possibly because they have less experience with high tunnel production, or perhaps because they are more likely to grow crops that do not show the same boost in quality.Because the self-funded or partially self-funded farmers rely on their farms for a greater share of their household income, they may invest more time in and attention to their high tunnels than their part-time counterparts, and therefore report more economic success with their high-tunnel production.

Policy Implications
We expected, based on national data, that beginning farmers would be more likely to obtain EQIP funding than their more experienced counterparts.For instance, beginning farmers made up 51% of EQIP cost-share recipients in 2013 (Huff, 2015), whereas 39.6% of our complete sample in Indiana (both EQIP-only and non-EQIP/combo) is beginning farmers.In addition, in our sample the EQIPonly group reported more years of farming experience than the non-EQIP/combo group, although the difference was not statistically significant (23.89 mean years of farming experience, compared to 19.69 years, respectively).This is more divergent when considering the median scores, with EQIPonly farmers having 25 years experience to the non-EQIP-combo farmers having 13.50 median years of experience.One possible explanation is that the cost-share program was only implemented in 2012 in Indiana, three years later than it was introduced in other states.It is possible that because the non-EQIP-combo group of farmers are generally younger and rely more heavily on their farms for income, some of them chose to invest in their own high tunnels rather than wait for the possibility that the EQIP program would be funded in Indiana.
The HTI, initially piloted under the Know Your Farmer, Know Your Food initiative, is well suited for the small-scale, diversified farms that sell their products into local food systems (Cole, n.d.;Farm News, 2009;Robillard, 2015;USDA NRCS, 2011;USDA, n.d.).Our data show that participation in the Indiana HTI reflects this programmatic focus on small farms that supply local food markets.Because high tunnels are a relatively low-cost investment that can be made up in just 1 or 2 years in many cases (Carey et al., 2009), the cost does not deter committed, commercial growers from investing in their own tunnels.Our study finds preliminary evidence that the program incentivizes small operations that may not have otherwise to experiment with a high tunnel, and that the infrastructure is relatively easy to adopt successfully.Thus the implications of our study for the HTI are that it incentivizes first-time users to adopt high tunnels and supports experienced growers in expanding their operation by adding additional tunnels to their farms.Taken together, the impact of the HTI is an increase in the volume of specialty crops grown for local food markets in the growing season and significant increases in off-season availability of fresh produce.The HTI also boosts the farm income of first-time users and especially more experienced, commercially scaled direct market farms, thus potentially boosting rural economies and local food systems.

Limitations and Future Research
Our study findings are limited by the relatively small size of the survey population (178), as the population of farmers that have utilized the HTI cost-share and invested in their own high tunnels in Indiana is relatively small overall.While our 63% response rate is better than the norm for mailed surveys (Dillman et al., 2008), the opportunity for nonresponse bias is still very present.To understand how nonresponse bias may affect these results, we attempted to solicit an abridged dataset from nonrespondents via telephone interviews (22% of nonrespondents were reached).The supplementary results suggest that the 22% of nonrespondents were having (1) some kind of challenge or problem with installing their high tunnel (e.g., it had yet to be installed), (2) difficulty in fully using their high tunnel, or (3) challenges in managing their farm, in general.These patterns among nonrespondents indicate that findings may be skewed toward positive experiences implementing high tunnel production on farms.In addition, the small sample creates a potential for bias in our findings that EQIP-only farms report lower economic impact of their high tunnels, because there is a larger proportion of small farms in that group.We cannot say if farm size and EQIP participation is correlated, or test whether larger farms in the EQIP-only group reported higher scores for the question about high tunnels "increasing overall profit," because the number of these farms in the sample is too small for a robust analysis.
This sample of farmers using high tunnels in Indiana prevents us from generalizing to farmers in climates with harsher winter seasons in the upper Midwest or Northeast, or those in the western and southern regions of the U.S. In addition, we are not able to generalize to areas where specialty crop production is more common and economically important than it is in Indiana, such as parts of the Upper Midwest, Northeast, Pacific coast, and urban areas where high tunnels may be more prevalent.Lastly, the small sample size limits the reliability of our observations in regards to differences between the two groups (EQIP-only and combo), and thus this analysis should be taken as preliminary and exploratory.
Qualitative research is needed to explore farmers' experience with using high tunnels in more depth.For instance, interviews with this population could identify the factors that explain why some farmers report very positive experiences with their high tunnels, while others have not used them to the same capacity or have experienced challenges with high-tunnel production.In addition, we would like to further explore and understand the significance of farmers' full-time or part-time status and the percentage of income they earn from their farms for their success in using high tunnels.

Conclusions
Overall, our results suggest that the HTI is meeting its stated goals of increasing the availability of fresh produce for local food markets and is enabling farmers to extend the growing season and improve the quality of their specialty crops.The survey provides evidence that in addition to these general goals, growing under cover allows farmers to improve the yield of their crops and generally reduce pest problems.Therefore, continuing the cost-share program could potentially improve the viability of specialty crop farms over time in a number of ways.We add to the very limited research assessing the farm-level economic impacts of the High Tunnel Initiative, demonstrating that farmers have increased their financial viability by growing under cover.We also provide greater depth of understanding about the types of farmers who have depended on the HTI to provide funding for a high tunnel and those who have invested their own funds in constructing one or more high tunnels.In the big picture, the study contributes to society's understanding of a key technology that can increase the viability of mostly smallscale farms that supply local food system initiatives.

Table 2 .
Descriptive and Comparison Results of Farm Characteristic Data Overall and Between Groups *p<.10; **p<.05;***p<.010 a Calculation based on gross sales and gross high tunnel square footage.

Table 4 .
Summary Statistics for Binary Stepwise Logistic Regression Model in which EQIP-only and Non-EQIP-combo are Compared for Most Salient Distinguishing VariablesIndependent variables retained in step 2 are listed in order of their Exp(B) score, with asterisks denoting significance level.