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2015 Comprehensive Assessment of Organic Production in Vermont: Experience from Two Systems, 2006-2013 Terence L. Bradshaw University of Vermont

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Recommended Citation Bradshaw, Terence L., "Comprehensive Assessment of Organic Apple Production in Vermont: Experience from Two Orchard Systems, 2006-2013" (2015). Graduate College Dissertations and Theses. 327. https://scholarworks.uvm.edu/graddis/327

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COMPREHENSIVE ASSESSMENT OF ORGANIC APPLE PRODUCTION IN VERMONT: EXPERIENCE FROM TWO ORCHARD SYSTEMS, 2006-2013

A Dissertation Presented by Terence L. Bradshaw to The Faculty of the Graduate College of The University of Vermont

In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Specializing in and Soil Science

May, 2015

Defense Date: March 25, 2014

Dissertation Examination Committee: Josef H. Gorres, Ph. D., Advisor Robert L. Parsons, Ph.D., Chairperson Lorraine P. Berkett, Ph.D. Sidney C. Bosworth, Ph.D. Cynthia J. Forehand, Ph.D., Dean of the Graduate College

ABSTRACT

Despite substantial consumer demand and willingness to pay premium prices for organically grown fruit, apple growers in Vermont and other New England states have been slow to adopt certified organic practices. Barriers cited in the past to increased adoption of organic apple production in the region include susceptibility of traditionally grown to , lack of effective insect pest management materials, and few available effective options for fruit thinning. Recent changes in apple plantings in the region, introduction of new insect pest management materials, and advances in thinning justified an evaluation of organic apple production systems containing cultivars identified as important to the future of the apple industry. In 2006, two apple were established at the University of Vermont Horticulture Research and Education Center in South Burlington, VT to comprehensively evaluate the five commercially-important apple cultivars of ‘’, ‘’, ‘’, ‘Macoun’, and ‘Zestar!’ over eight growing seasons in two organically-managed orchard production systems, including a newly-planted high-density orchard (Orchard 1) and in an existing, medium-density orchard which was top-grafted to the new cultivars (Orchard 2). Parameters for tree growth and survival, crop yield, disease and arthropod pest incidence on foliage and fruit, and long-term economic return, including a twenty-year projection of net present value (NPV) of each cultivar in the two systems were evaluated in this study. ‘Ginger Gold’, despite high incidence of some diseases on foliage and fruit, performed the best in both orchard systems overall. The cultivar was among the cultivars with the highest measurements of tree growth. ‘Ginger Gold’, along with ‘Honeycrisp’, had the highest cumulative net crop yield per tree in Orchard 1 and the highest in Orchard 2. Notably, apple scab on ‘Honeycrisp’ foliage and fruit and ‘Zestar!’ fruit in both orchards was at a level that was not significantly different from ‘Liberty’, a scab-resistant cultivar on which no scab was observed. However, ‘Honeycrisp’ had the highest incidence of fruit rots in both orchards, but it was not significantly different than ‘Zestar!’ in Orchard 1. Management of lepidopteran pests of fruit was a challenge on all cultivars over the years of the study. For most of the tree growth parameters and cumulative net crop yield, ‘Liberty’ was among the lowest group of cultivars in both orchards. Cumulative net crop yield of both ‘Macoun’ and ‘Zestar!’ were also among the lowest in both orchards with the top-grafted ‘Macoun’ and ‘Zestar!’ trees having significant tree death compared to the other cultivars in Orchard 2. Harvested fruit were graded to commercial standards and cumulative gross and net income calculated from grade distribution, crop yield, and fruit price data. In Orchard 1, ‘Ginger Gold’ and ‘Liberty’ had greater cumulative gross income per hectare from 2006-2013, in excess of US$40,000, compared to ‘Liberty’. However, after management costs were deducted, all cultivars in Orchard 1 had negative cumulative net income of $-77,892 or less. In Orchard 2, all cultivars had positive cumulative net income for 2006-2013, and ‘Ginger Gold’ had the highest at $109,717/ha. The twenty-year projected NPV was negative for all cultivars in Orchard 1, but in Orchard 2, all cultivars had positive NPV with ‘Ginger Gold’ having the highest among the cultivars. ACKNOWLEDGEMENTS

Twenty years ago while an undergraduate UVM Plant & Soil Science student, I answered a flyer in the stairwell of Hills Building advertising a summer job opportunity working for the Apple Research Team. Little did I know then that that job would lead to a long and fruitful professional career, and I owe Lorraine Berkett, head of the program for 31 years, my respect and gratitude for shepherding me along the way. Lorraine saw my potential as a researcher and educator well before I did, and her encouragement, support, and guidance as my supervisor, mentor, and advisor has been indispensable in my efforts. I also wish to thank Tom Vogelmann, Josie Davis, and Skip Fanus in the CALS Dean’s office and PSS Chair Deb Neher for seeing my potential to carry on the program after Lorraine’s retirement, and supporting my transition to a faculty role. The research associated with this dissertation was truly a team effort. The Primary Investigators of the OrganicA project, including Lorraine, Renae Moran, Elena Garcia, Heather Darby, and Bob Parsons, saw a unique research opportunity over ten years ago and have been instrumental in seeing this project through. My fellow technicians Sarah Kingsley-Richards, Morgan Cromwell, and Andrew Bessette contributed countless hours of effort to the project. I also wish to thank Joan Skelly and Alan Howard for statistical support, and the many undergraduate students who helped with orchard maintenance and research activities. Finally, none of this work would be worth doing if not for the Vermont apple grower community, for whom my work with tree fruit production systems is designed to support. Life is not defined solely by the work we perform at our jobs, no matter how important it is. The demands of an academic and administrative career while pursuing a graduate degree are not insignificant, and I have spent many hours secluded at my home office desk ‘after work’ in order to get it all done. To that point, I thank my wife Julie and daughter Alice for their tolerance for missed family events and my many distractions during this process, and for their support and encouragement along the way.

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TABLE OF CONTENTS

ACKNOWLEDGEMENTS ...... ii LIST OF TABLES ...... vi LIST OF FIGURES ...... vii CHAPTER 1: COMPREHENSIVE LITERATURE REVIEW ...... 1 Organic orchards in the U.S...... 1 Principles of organic integrated pest management ...... 3 Apple scab management in organic orchards ...... 7 Phytotoxicity and organic apple scab management ...... 12 Other apple diseases of concern in organic orchards ...... 16 Insect pest management in organic apple orchards ...... 20 Horticultural challenges in organic apple orchards ...... 23 Economic evaluations of organic apple production systems ...... 31 Literature cited ...... 42 THE ORGANICA PROJECT: A GENERAL OUTLINE FOR THIS DISSERTATION ...... 56 CHAPTER 2: JOURNAL ARTICLE- TREE GROWTH AND CROP YIELD OF FIVE CULTIVARS IN TWO ORGANIC APPLE ORCHARD SYSTEMS IN VERMONT, USA, 2006-2013 ...... 59 Abstract ...... 59 Introduction ...... 60 Materials and methods ...... 61 Tree survival and growth ...... 63 Crop yield ...... 64 Statistical analysis...... 65 Results and discussion ...... 65 Tree survival and growth ...... 65 Crop yield ...... 69 Literature cited ...... 76 CHAPTER 3: JOURNAL ARTICLE- DISEASE AND ARTHROPOD PEST INCIDENCE IN TWO ORGANIC APPLE ORCHARD SYSTEMS IN VERMONT, USA, 2008-2013 ...... 83 Abstract ...... 83

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Introduction ...... 84 Materials and methods ...... 85 Experimental design and orchard management ...... 85 Disease and arthropod assessment on foliage...... 88 Disease and arthropod assessment on fruit ...... 89 Statistical analysis...... 90 Results and discussion ...... 91 Foliar diseases and arthropods ...... 91 Disease and arthropod damage on fruit ...... 94 Literature cited ...... 102 CHAPTER 4: JOURNAL ARTICLE- LONG-TERM ECONOMIC EVALUATION OF FIVE CULTIVARS IN TWO ORGANIC APPLE ORCHARD SYSTEMS IN VERMONT, USA, 2006-2013 ...... 110 Abstract ...... 110 Introduction ...... 111 Materials and methods ...... 112 Orchard site and experimental design ...... 112 Orchard management ...... 113 Input costs ...... 114 Fruit grading ...... 115 Yield and income ...... 116 Net Present Value ...... 117 Statistical analysis...... 117 Results and discussion ...... 118 Input costs ...... 118 Fruit grade...... 119 Yield and income ...... 121 Net Present Value ...... 122 Literature cited ...... 126 CHAPTER 5: COMPREHENSIVE SUMMARY OF THE ORGANICA PROJECT AND AREAS FOR FURTHER INVESTIGATION...... 134 Introduction ...... 134 Orchard establishment and experimental design ...... 135

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Orchard management ...... 138 ...... 138 Organic pest management ...... 140 Horticultural evaluation...... 143 Disease and arthropod pests on foliage ...... 145 Disease and arthropod pests on fruit ...... 146 Abiotic damage to fruit ...... 147 Fruit grade assignment ...... 149 Economic evaluation ...... 151 Input costs ...... 151 Income ...... 154 Net present value ...... 156 Literature Cited ...... 158 COMPREHENSIVE BIBLIOGRAPHY ...... 171 APPENDICES ...... 190 Appendix 1: The rationale and major objective in the USDA grants that funded the ‘OrganicA project’ including the list of investigators ...... 190 Appendix 2: Orchard maps ...... 194 Appendix 3: table...... 197 Appendix 4: Foliar tissue analyses ...... 198 Appendix 5: Organic treatments in Orchards 1&2 ...... 200 Appendix 6: Weekly codling moth trap captures, 2008-2013 ...... 201 Appendix 7: Figures of biotic (disease and insect pest) and abiotic damage on fruit . 202 Appendix 8: USDA Apple Grading Standards ...... 205 Appendix 9: Detailed, actual annual labor, equipment, and input costs, $US/ha...... 215

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LIST OF TABLES

Table 2.1 Tree survival and growth measurements ...... 80 Table 2.2 Annual harvested kg of fruit per tree, 2008-2013 ...... 81 Table 2.3 Cumulative yield, yield efficiency, fruit weight, and preharvest fruit drop...... 82 Table 3.1 Mean percent incidence and severity of foliar disease, 2008-2013 ...... 106 Table 3.2 Mean percent incidence of foliar arthropods, 2008-2013 ...... 107 Table 3.3 Mean percent incidence of disease damage to fruit at harvest, 2008-2013 ...... 108 Table 4.1 Equipment, labor, and input costs ($US/ha)...... 129 Table 4.2 Commercial fruit grade distribution, 2008-2013 ...... 130 Table 4.3 Cumulative yield, gross income, & net income, 2006-2013 ...... 131 Table 5.1 Annual harvested crop yield, MG/ha...... 163 Table 5.2 Mean percent incidence of abiotic fruit defects, 2008-2013 ...... 164 Table 5.3 Mean annual percent incidence of hail damage on fruit, 2008-2013 ...... 165 Table 5.4: Annual costs (US$/ha) for hand thinning fruit, 2009-2013 ...... 166 Table 5.5: Annual gross income (US$/ha) for harvested fruit, 2007-2013...... 167

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LIST OF FIGURES

Figure 4.1: NPV of accumulated cash flow ($US/ha) 2006-2025 ...... 132 Figure 5.1: Trunk cankers on dead trees, Orchard 2 ...... 168 Figure 5.2: Size of typical trees in Orchard 1 ...... 169 Figure 5.3: Annual fruit grade distribution, 2008-2013 ...... 170

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CHAPTER 1: COMPREHENSIVE LITERATURE REVIEW

ORGANIC ORCHARDS IN THE U.S.

In 2009, organic food production occurred on 32 million hectares worldwide, representing 0.8% of total agricultural land (Willer et al., 2009). United States (U.S.) cropland under organic management totaled 1.05 million hectares or 0.7% of total cropland in 2008, and of that 7141 hectares were organic apple orchards (USDA Economic

Research Service, 2013). Apple orchards are planted on 4,534 ha in New England, with an average utilized production value from 2009-2013 of $66.7 million (NASS, 2014).

Vermont has approximately 1,092 ha in apple production which generate $8.9 million in annual cash receipts and $12.8 million in value-added products (NASS, 2012). However, out of the estimated 85 commercial orchards in Vermont, only five were certified organic in 2009 (N. Dehne, pers. comm.), and no organic fruit production in Vermont was counted in USDA statistics (USDA Economic Research Service, 2013). In 2013, eleven certified organic farms in Vermont listed as a commercial crop (NOFA-VT, 2013).

Consumption of organic foods represented an increasing market in 2009, with sales of $24.8 billion and growth of 5.1 percent overall, including 11.4 percent for fruits and vegetables (Organic Trade Association, 2010a). Wholesale organic apple prices in 2008 averaged 48 and 62 percent higher in San Francisco and Boston markets than non-organic apples, respectively (USDA Economic Research Service, 2009). However, organic apples in both markets were primarily produced in Washington State, and due to increased disease pressure, growers in wet regions in the northeastern U.S. face greater difficulty in producing organic apples than growers in semi-arid western states (Sayre, 2004,

1

Granatstein and Kirby, 2006). A Vermont study found that a niche market for organic apples could exist in the state, and that consumers would be willing to pay higher prices for them (Wang et al., 2010), but consumers of organic and ‘ecolabel’ apples change purchasing patterns to non-organic fruit when quality diminishes (Wang et al., 2010,

Loureiro et al., 2001, Yue et al., 2007). In order to supply this potential market, organic apple production must be economically feasible, while supplying comparable fruit quality to conventional, non-organic apples.

Challenges to increased commercial production of organic apples in the northeastern U.S. include pest and disease pressure, groundcover management, tree nutrition management, tree vigor and crop yield (Earles, 1999, Moran, 2007). In total, those challenges have resulted in little production of certified organic apples in the northeastern

U.S. In contrast, organic commercial apple production is more common in Western U.S. states, especially in the arid region east of the Cascade Mountains where organic production accounts for nearly 10% or total apple production (Slattery et al., 2011). Under the weather conditions and with the pest complex found in eastern Washington, organic apple production has compared favorably to conventional, non-organic production systems in multi-year studies. In one six-year study of organic, conventional, and hybrid production systems in Washington (Reganold et al., 2001), crop yield was greater for organic treatments than conventional in two of five years, and conventional treatments had greater crop yield than organic treatments in three years. There was no difference in cumulative yield over five years between any of the treatments in the study. The organic treatment was more profitable than conventional and integrated treatments in two of the three years of the study which had the greatest fruit production, but increased production costs for organic

2 treatments resulted in lower net returns in the early establishment years when crop yield was low. This highlights an important consideration for organic production systems: increased costs over conventional fruit production systems must be recouped via sufficient crop yield and price. In a continuation study in the same orchard, crop yield was lower for organic than conventional treatments in one year, but the opposite was true in the following production year (Peck et al., 2006). Overall, organic production of tree fruit was feasible in eastern Washington, which is also evident from production statistics (Kirby and

Granatstein, 2012).

PRINCIPLES OF ORGANIC INTEGRATED PEST MANAGEMENT

Insect and disease pest management in organic apple production systems is commonly cited as the primary impediment to increased adoption in the northeastern U.S.

(Peck and Merwin, 2009). Since the 1970s, growers of commercial perennial like apples have used integrated pest management (IPM) protocols to manage disease, insect, and weed pests while maintaining fruit quality and minimizing chemical inputs (Whalon and Croft, 1984). Management tactics commonly used against arthropod pests in organic orchards include those used in non-organic orchards that use Integrated Pest Management

(IPM) practices. IPM is an holistic management system that relies on: knowledge of pest and crop biology; field monitoring of pest and beneficial organisms; accurate weather data collection and application to pest life cycle models; and physical, cultural, biological, and chemical practices to manage pests in (Gray et al., 2008, Ehler, 2006). IPM systems are not black-and-white, however, and various levels of IPM have been proposed to compare the degree of integration in a managed farm system to that of the ideal where pest and predator species are balanced to provide ecological pest

3 control without addition of external inputs (Prokopy, 1993). First-level IPM integrates chemical and biological strategies for a single class of pests; second-level IPM integrates multiple strategies across all classes of pests; third-level IPM emphasizes integration of pest management strategies across all factors of crop production on the farm, including crop, soil, and pest management; finally, fourth-level IPM incorporates social, cultural, and political components within and surrounding the farm system to address needs of producers, consumers, environmentalists, technical support personnel, foods distributors, and regulatory agencies. Conventional (non-organic) apple growers in the U.S., supported by Extension and research personnel and technical consultants, largely rely on first- and sometimes second-level IPM programs to manage crop production (MacHardy, 2000).

Such programs are codified in formal publications and outreach programs developed over many decades by collaborating growers, scientists, and supporting agencies. For example, collaborators in New England produce the New England Tree Fruit Management Guide annually, which is the primary resource used by growers to guide pest management decisions (Cooley et al., 2014). Practices used in modern apple IPM programs include: use of insect and disease modelling to time management practices and minimize unnecessary pesticide applications; planting of disease resistant cultivars and rootstocks; scouting programs that quantify pest and beneficial predator populations; orchard sanitation to reduce overwintering disease inoculum , insect pests , and weed pests; and orchard architecture and training systems to more efficiently manage pests within the planting.

Organic apple production systems include important components of IPM systems, and may be considered a type of IPM. The United States Department of

(USDA) National Organic Standards Board (NOSB) defines organic agriculture as "an

4 ecological production management system that promotes and enhances biodiversity, biological cycles, and soil biological activity. It is based on minimal use of off-farm inputs and on management practices that restore, maintain, or enhance ecological harmony…The primary goal of organic agriculture is to optimize the health and productivity of interdependent communities of soil life, , animals and people." (National Organic

Standards Board (NOSB), 1995). Producers of organic foods must adhere to standard regulations for acceptable growing practices, as enacted under the Organic Foods

Production Act of 1990. Farmers are certified by accredited, independent agencies in each state to ensure that national standards are met. State agencies may establish stricter guidelines than the USDA rules but may not be more lenient than the Federal standard

(Organic Trade Association, 2010b). In addition to general guiding principles referenced in their organic definition, the NOSB maintains a National List of acceptable materials for use in organic production systems. Generally those materials allowed on the list are naturally occurring substances that do not pose undue harm to health or the environment.

Some synthetic materials are allowed by the NOSB under certain circumstances (National

Organic Program, 2010). Formulated products allowable for use in certified organic crop production are evaluated by the Organic Materials Review Institute (OMRI, http://www.omri.org/omri-lists) and their final acceptance in Vermont is certified by

Vermont Organic Farmers, LLC (Richmond, VT).

The requirement for an ecologically-based production management system for organic certification is similar to second- and third-level IPM. Therefore, the primary difference between IPM and organic systems is the prohibition of most synthetic inputs in certified organic systems. In a comparison survey of organic and conventional apple

5 producers in the U.S. (Slattery et al., 2011), production practices in both systems were very similar. The report largely reflects growing conditions in the arid Western U.S., however, due simply to the scale of the industry in Washington which reported 91% of U.S. organic apple production acreage. Primary cultivars included , ,

Gala, , and for both systems. Both conventional and organic apple producers used to control orchard pests, but the type of materials used were different, with biological and mineral-based spray materials more common in organic systems. Non-chemical practices were used extensively in both systems, e.g.: conservation was practiced in 60% and 74% of conventional and organic systems, respectively; sanitation via removal of crop debris by 67% and 58%; orchard scouting was performed by 89% of conventional and 84% of organic growers; and weather monitoring by 86% and 68%, respectively. In the northeastern U.S., rainfall and humidity promote disease development more than in arid environments, and insect pests including plum curculio and apple maggot exist that are not present in Western production regions.

This difference in disease and pest pressure in the northeastern U.S. is responsible for greater use of organically-approved pesticides compared to Western states, and is a limiting factor to widespread adoption of organic systems in the region (Earles, 1999). For example, apple scab is managed in organic orchards with applications of copper, sulfur, or lime sulfur applied every 5-10 days from bud break through June (Peck and Merwin,

2009). In arid Western states, apple scab is not a serious concern and may be managed with a few sulfur sprays targeted at other diseases, but sulfur sprays used for management of powdery mildew may bring the amount of spray material in-line with northeastern U.S. growers (Hinman and Ames, 2011, Reganold et al., 2001). In spite of the ecological

6 foundation of organic production programs, the reliance on organic certifier-approved chemical pesticides in organic production systems as part of an ‘organic IPM’ strategy make this systems similar to conventional IPM systems. Specific practices used by organic growers to manage pests and crops are described below.

APPLE SCAB MANAGEMENT IN ORGANIC ORCHARDS

The most economically significant disease in the northeastern U.S. is apple scab, caused by the fungus Venturia inaequalis (Cooke (Wint.)) (MacHardy, 1996). Infections originate primarily from ascospores that develop in lesions in overwintered leaves on the orchard floor which were infected in the previous season. Ascospores from the overwintering fungus mature around the time buds open in the spring, and are released during rain events. Ascospore maturation occurs over several weeks, depending on temperature and moisture conditions. Released ascospores land on susceptible leaf and fruit tissue and germinate, causing infection. This process requires free moisture on susceptible tissues, and a model has been developed to determine whether or not infection occurred based on the length of time moisture was present and the temperature during the wetting period (MacHardy and Gadoury, 1989). During this ‘primary infection period’ (i.e., when mature ascospores are being released), orchards are typically protected by prophylactic applications, although some materials are used which provide post-infection control of the disease (Cooley et al., 2014). If apple scab infections can be prevented during the period when ascospores (i.e., primary inoculum) are released, then the disease will be managed for the present season. However, if infection from ascospores occurs, the resulting lesions on apple leaf and fruit tissues produce secondary spores in the form of conidia which can cause new infections for the remainder of the season. Thus, management of

7 apple scab is critical during the primary infection period from the green tip bud stage until a wetting rain event 900 degree days (base 32° F) later releases the last of the primary inoculum (MacHardy and Gadoury, 1985). Because the apple scab fungus requires leaf wetting during the early spring season for spore germination and infection to occur, and the relatively cool, wet climate in the northeastern U.S. is conducive to disease development compared to arid production regions in western U.S., active management of this disease with prophylactic fungicide sprays is essential for successful fruit production with susceptible cultivars in the region.

IPM strategies for managing apple scab include modelling and initial inocolum assessment . Disease modelling is used by most growers to time fungicide applications based on determining whether or not an infection period occurred following periods of wet weather (MacHardy and Gadoury, 1989, Mills, 1944). The modified Mills model, however, uses leaf wetness data that can only accurately be assessed after the wetting event, and although some predictive element can be derived from the model if short wetting events are forecast, fungicide application decisions are typically made and fungicides are applied before an infection period occurs given the importance of managing the disease during the primary infection period. Growers therefore tend to maintain coverage of protective fungicides for the duration of the primary infection period from green tip through the 900 degree day period. If overwintering inoculum is low, growers may assume that the initial ascospore inoculum will also be low, so practices have been developed to eliminate sprays early in the season. The potential ascospore dose (PAD) model requires growers to assess orchards by visual examination of terminal leaves in autumn to determine relative levels of apple scab in the orchard (Reardon et al., 2005, MacHardy, 1998); if below a specified

8 threshold, early sprays can be eliminated in the following spring. PAD is not commonly used by northeastern U.S. apple growers, however, because data must be collected during harvest when growers have little free time available for assessment, and because of the relatively low cost of fungicide applications compared to the consequences of allowing primary infection in the orchard (Penrose, 1995). Organic apple growers should use predictive tools to assess potential apple scab risk as part of their holistic management plan approved by their certifying agency, but levels of scab in orchards of susceptible cultivars managed with application of mineral fungicides will typically be above the PAD threshold in most years (Berkett et al., 2013, Rosenberger and Jentsch, 2006). While the PAD model has not been adequately tested under organic conditions to recommend its use in commercial orchards, the concept of inoculum reduction is important in the overall holistic management plan.

Reduction of overwintering inoculum through orchard sanitation is an important component of apple scab IPM programs. One component of the PAD model is a ‘sanitation threshold’, in which sanitation practices applied to reduce overwintering inoculum would shift the orchard into a ‘low risk’ category where initial fungicide sprays prior to tight cluster bud stage may be eliminated (MacHardy, 1998). Sanitation practices, including shredding leaves after leaf fall in autumn or early in spring prior to bud break and application of urea to leaf litter may reduce risk of apple scab development by up to 90% if applied thoroughly (MacHardy, 1998). Urea application is prohibited under NOSB standards in organic orchards, but leaf shredding with a flail mower is an acceptable and recommended practice. Applications of lime or to leaf litter have been suggested to reduce apple scan inoculum (Phillips, 2005), but those practices have not been evaluated

9 in replicated trials. Sanitation practices including leaf shredding and plowing under leaves have been proven effective in commercial, non-organic orchards in New Hampshire and

France (MacHardy et al., 2000, Gomez et al., 2007), but they have not been completely effective in organic orchards (Holb, 2008).

Another method to reduce inoculum and manage apple scab in orchards is the use of scab-resistant cultivars. Some apple cultivars have been bred for resistance to apple scab, and may present an opportunity for growers who wish to adopt organic practices. In numerous studies, trained panels have identified scab-resistant cultivars that may be acceptable to consumers (Tomala et al., 2009, Jönsson, 2003, Kühn and Thybo, 2001,

Kellerhals et al., 2001, Kelley et al., 2010). Since the 1940s, numerous apple cultivars genetically-resistant to scab have been bred and released but few have gained acceptance with U.S. apple growers or marketers. Growers cite uncertainty with cultural needs of the fruit, lack of cultivars with proven profitability, and consumer reluctance to buy new apple cultivars, especially on the wholesale market, as reasons for not adopting scab-resistant cultivars on a large scale (Rosenberger, 1995, Murphy and Willett, 1991). Also, because installation of new orchards and marketing of new cultivars is both costly and risky, growers tend to plant cultivars with proven marketing potential. Liberty, a scab-resistant cultivar released from Cornell University in 1978, is a scab-resistant apple planted in

Vermont orchards that has some market recognition, but is not widely grown in on significant acreage in the state (VTFGA, 2011).

While scab-resistant cultivars present unique opportunities for organic apple production in Vermont, they are not yet widely planted. ‘McIntosh’ continues to be the most-planted cultivar in Vermont, followed by other cultivars bred from it (e.g., ‘’,

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‘’), but new cultivars being planted are increasing as a share of the cultivar mix in the state’s orchards (VTFGA, 2011). Notable newer cultivars that have become established in the marketplace in recent years include ‘Ginger Gold’, ‘Honeycrisp’, and ‘Zestar!’, as well as ‘Macoun’, an older cultivar with strong consumer following in New England, have varying susceptibility to scab when compared to the industry standards such as ‘McIntosh’, which is very susceptible to apple scab. It is important to conduct research to determine if the incorporation of these newer cultivars, which have potentially more resistance to apple scab than ‘McIntosh’, into organic management systems would result in sustainable, profitable systems.

On apple scab-susceptible cultivars, organic management of the disease primarily relies on preventative applications of approved mineral-based inorganic fungicides during the primary infection period. Copper materials are used to a small extent and usually in a single application at bud break because copper causes fruit russeting, leaf yellowing, and defoliation when applied later in the season (Teviotdale and Viveros, 1998, Bell, 1941,

Privé et al., 2006, Brown et al., 1996). Sulfur and lime sulfur are the primary materials used in organic apple scab management programs in the northeastern U.S. (Peck and Merwin,

2009, Hinman and Ames, 2011). Both materials have shown efficacy in management of apple scab since the early 20th century (Mills, 1944), but were replaced in non-organic orchards when more effective synthetic fungicides were developed after World War II

(Matolcsy et al., 1988). However, as organic production systems were developed by independent certifiers and formalized by NOSB, sulfur and lime sulfur fungicides became the standard apple scab management tool for organic apple growers. Modern, organically- acceptable formulations of both sulfur and lime sulfur are listed as the most effective

11 organically-acceptable materials for apple scab management in recommendations of

Extension professionals in New England, but they are only rated as ‘fair’ and have lower efficacy against the disease than many synthetic materials (Cooley et al., 2014). Sulfur is not effective in post-infection applications, so must be applied preventatively to manage the disease. Lime sulfur, however, has been shown to have activity against apple scab when applied within 72-96 hours after infection (Trapman, 2002, Holb et al., 2003), and thus is an important tool available to organic apple growers.

PHYTOTOXICITY AND ORGANIC APPLE SCAB MANAGEMENT

The use of sulfur and lime sulfur has had negative impacts in orchards including phytotoxicity. The phytotoxic mode of action of sulfur is not fully known, but it likely penetrates plant tissue and acts as a hydrogen receptor, thus disturbing metabolic processes

(Matolcsy et al., 1988). Lime sulfur is more phytotoxic than elemental sulfur due in part to its caustic nature which causes more extensive penetration into plant cells (Matolcsy et al.,

1988, Montag et al., 2005). Studies have documented decreased leaf chlorophyll, leaf size, total yield, and fruit size on trees treated with both sulfur and/or lime sulfur (Hoffman,

1935, Hyre, 1939, Burrell, 1945, Palmiter and Smock, 1954). Liquid lime sulfur has been found to decrease light-saturated photosynthesis after application, which has direct effect on final fruit set and yield (McArtney et al., 2006, Palmer et al., 2003). Use of either lime sulfur or elemental sulfur in New Zealand has been found to decrease photosynthesis by nearly 50%, although leaf size and shoot length were not affected during the one-year study

(Palmer et al., 2003). Reduction in leaf photosynthesis from a single sulfur application on trees has been found to persist for 11 days with a 50% reduction after 20 days which continued for the 45-day experiment (Ferree et al., 1999). Furthermore, effects of

12 sulfur application on photosynthesis are exacerbated by increased respiration in apple leaves which have received sulfur sprays (Hyre, 1939). Sulfur residues on plant tissues also exhibit a lens effect which may reduce absorption of UV radiation required for plant photosynthesis (Turrell, 1950). However, researchers in New Zealand suggest that transitory effects of reduced photosynthetic activity of spur leaves may be offset by normally growing vegetative shoot leaves under their local growing conditions (McArtney et al., 2006), which suggests that reduced tree growth and fruit production may be alleviated with optimal orchard management and growing conditions.

Another negative side effect associated with sulfur and lime sulfur use in orchards is the potential to increase (‘flare’) phytophagous mite populations. Phytophagous mites are generally considered an induced pest in orchardsbecause their populations are typically held in check by natural predators. The two primary phytophagous mite pests of apple trees in the northeastern U.S. are the European red mite (Panonychus ulmi (Koch)) and two- spotted spider mite (Tetranychus urticae (Koch)) (Agnello et al., 2006). Lime sulfur and sulfur have miticidal effects on both phytophagous and predatory mites species, and are in fact listed as miticides (Beers et al., 2009). However, the impact that those materials have on predatory mites may impact biological management of phytophagous species. Increased phytophagous mite populations in apples associated with as few as three applications of sulfur and/or lime sulfur has been observed in field studies (Holdsworth, 1972, Beresford et al., 1996). Mites are indirect pests, in that they do not affect or damage fruit directly, but rather feed on photosynthate and other compounds in plant leaves that leads to overall plant health decline. Feeding activity of both European red mite and two-spotted spider mite has decreased carbon dioxide exchange, net photosynthesis, fruit growth, fruit quality, tree

13 growth, and fruit bud formation in several studies (Lakso et al., 1996, Marini and Pfeiffer,

1994, Mobley and Marini, 1990, Lienk, 1980, Hall and Ferree, 1975, Francesconi et al.,

1996).

Effective, organically-acceptable fungicide alternatives to copper, sulfur, and lime sulfur for management of apple scab on susceptible cultivars are not widely available.

Potassium bicarbonate has been used either alone or in combination with sulfur to manage apple scab in some studies in Switzerland and the Netherlands (Jong and van der Maas,

2008, Tamm et al., 2006).. In two Belgian studies (Jamar and Lateur, 2006, Jamar et al.,

2008), potassium bicarbonate was effective compared to sulfur and lime sulfur but only when applied in a ‘during infection’ strategy, under which preventative applications of fungicides were avoided. Spray timings were based on real-time weather monitoring in order to precisely determine the beginning of infection periods, and sprays applied immediately during wetting events when infection was predicted. Spray timing was critical in the studies, and specialized equipment that enclosed the orchard canopy during application was required. Given typical orchard architecture and labor and equipment availability, this strategy is not likely to be feasible in larger-scale orchards. The management implications of missing coverage during a single primary infection period are important, because lesions that result from the infection will sporulate and produce conidia that extend apple scab management through the rest of the growing season (MacHardy,

1996).

Biologically-derived fungicides (biofungicides) are formulated from live cultures of bacteria or fungi, and have shown minimal efficacy against the apple scab fungus in replicated studies. In a review of Bacillus-based biofungicides, reports of successful foliar

14 disease management were scarce, and no studies on apple scab management were included

(Jacobsen et al., 2004). Some Bacillus species isolated from stored fruit exhibited virulence to Botrytis species in laboratory studies (Sholberg et al., 1995, Touré et al., 2004). Bacillus subtilis, the active ingredient in the commercial fungicide Serenade®, exhibited mixed performance against the bacterial disease fire blight, but was most effective in rotation with antibiotics, and no reports of activity against apple scab or other important fungal diseases of apples have been reported (Laux et al., 2003, El-Goorani and Hassanein, 1991, Sundin et al., 2009). Serenade® had no effect on the incidence of fruit rots in one New Zealand study (Everett et al., 2007). Fungal antagonists applied to leaf litter in autumn to reduce overwintering apple scab inoculum have shown promise, but have not been formulated to date into a commercially-available, effective management tool (Carisse et al., 2000,

Andrews et al., 1983, Köhl et al., 2009).

In a multi-year evaluation in Vermont of organically-approved fungicide alternatives to sulfur and lime sulfur, no materials were found to have efficacy against apple scab equal to those materials (Cromwell et al., 2011). In that study, potassium, bicarbonate, Bacillus subtilis, and clarified extract of neem oil were evaluated against a standard organic sulfur/lime sulfur fungicide program and a non-treated control. The neem oil treatment reduced foliar and fruit scab compared with the non-treated control and the other alternatives at the end of one growing season. In each year of the study, one or more of the alternative treatments, particularly Bacillus subtilis, resulted in higher insect damage than the non-fungicide-treated control. The study concluded that potassium bicarbonate,

Bacillus subtilis, and neem oil did not offer advantages over the standard sulfur/lime sulfur

15 fungicide program in organic apple production and in some cases offer distinct disadvantages in terms of non-target impacts.

OTHER APPLE DISEASES OF CONCERN IN ORGANIC ORCHARDS

Although apple scab is the primary focus of disease management in northeastern

U.S. organic orchards, several other commercially-important diseases affect the crop. The focus on apple scab management, either through use of sulfur and lime sulfur or resistant cultivars, typically manages the disease, but may allow secondary diseases to increase in importance. For example, apple rust diseases (Gymnosporangium spp.) are difficult to manage with organically-acceptable materials (Earles, 1999). Sulfur is listed as having no efficacy against cedar apple rust in the New England Tree Fruit Management Guide

(Cooley et al., 2014), and results from a two-year study of organically-approved fungicide materials in Vermont support that assessment (Cromwell, 2009). Alternative, organically- acceptable fungicide materials assessed in that study also had little affect against the disease. Cultivar resistance to rust diseases is an important management tool, but many commercially-important cultivars are susceptible to the disease (Biggs et al., 2009).

Because of the importance of managing apple scab in northeastern U.S. orchards, especially in those managed organically, cultivar selection for disease resistance is likely to be focused on apple scab and not rust diseases. Removal of alternate hosts is another important cultural tool for rust disease management, but because the spores of

Gymnosporangium spp. may travel over three kilometers, this may be difficult in most situations (Kelley and Laemmlen, 1980). Rust diseases of apple are not considered a significant problem in most non-organic orchards in the northeastern U.S. because they are typically managed by synthetic fungicides applied to manage apple scab. In grower and

16 stakeholder evaluations conducted in the region over two years, rust diseases ranked sixth in importance of nine identified diseases (Northeast IPM Tree Fruit Working Group, 2012).

However, the survey primarily reflected non-organic orchards where standard, conventional IPM programs had successfully managed the disease. For organic growers, rust diseases may be of greater importance than was reflected in those evaluations.

Fruit rot diseases are a significant concern for apple growers, because affected fruit are typically culled automatically when symptoms are present and cannot be sold (USDA,

2002). Rotting fruit also may produce inoculum which may spread and infect other fruit in storage, which may further increase the economic impact of disease incidence. Several fruit rot diseases occur on apples in the northeastern U.S., including bitter rot (Colletotrichum gloeosporiodes (Penz.) Penz & Sacc.), black rot (Botryosphaeria obtuse (Schwein)), white rot (Botryosphaeria dothidea (Moug) Ces. & De Not). This is in contrast to rots typically found on stored fruit that are inoculated from bins and storage surfaces, and thus are not treated in orchard spray programs, e.g. blue mold (Pennicillium spp.), gray mold (Botrytis cinerea (Pers.)), and bull’s -eye rot (Pezicula malicorticis, (H. Jacks) Nannf.) (Jones and

Aldwinckle, 1990). Fruit rot diseases are typically managed by protective fungicide spray programs in most non-organic production systems, but reduction in or elimination of the use of synthetic fungicides in organic or low-spray programs may increase significance of those diseases (Merwin et al., 1994). In studies in Vermont and New York, the use of sulfur and/or lime sulfur fungicides in organic orchards has been associated with surface damage

(i.e., russeting, lenticel spotting, scarf skin) on fruit (Peck et al., 2010, Cromwell et al.,

2011). Such damage may reduce a fruit’s defense against rot organisms by compromising its skin and opening lenticels up to infection, and is considered an important factor in

17 increasing susceptibility to rot diseases (Sitterly and Shay, 1960). Thus, organic orchards in which apple scab is managed with sulfur and/or lime sulfur fungicides may be more susceptible to fruit rot diseases than non-organic or non-sprayed orchards.

Other summer diseases of apples that typically are managed by commercial growers include sooty blotch (caused by the complex: Peltaster fructicola (Johnson, Sutton,

Hodges); Geastrumia polystigmatus (Batista & M.L. Farr); Leptodontium elatus (G.

Mangenot) De Hoog; and Gloeodes pomigena (Schwein) Colby) and flyspeck (Zygophiala jamaicensis (E. Mason)). These diseases cause purely superficial, cosmetic damage to fruit, and may be removed with scrubbing, although that post-harvest removal is labor-intensive and may damage the fruit surface (Batzer et al., 2002). Sooty blotch (SB) and flyspeck

(FS), when present in small amounts, may reduce fruit to a lower-value grade if the aggregate area of infection is greater than ¼” (6 mm) (USDA, 2002). Retail (pick-your- own or farm stand) orchards that do not grade fruit to USDA standards may see reduced demand for produce with cosmetic blemishes from SB and/or FS. While SB and FS are diseases that only cause cosmetic damage, consumers, including those who identify themselves as ‘organic-preferred’ shoppers, will reject heavily infected fruit (Yue et al.,

2007). Organic apple growers often must accept higher cosmetic damage to fruit because pest management options are more limited, but pest and disease-damaged fruit has been associated with reduced consumer willingness to pay in several studies (Yue et al., 2009,

Thompson and Kidwell, 1998, Krystallis and Chryssohoidis, 2005).

SB and FS diseases have likely affected apples since importation of the fruit to

North America in the 1600s. The incidence of both diseases has fluctuated in the past two centuries as market standards, available fungicide materials, and orchard architecture have

18 changed, with a recent uptick since 2000 (Williamson and Sutton, 2000) SB has been effectively managed with organically-approved methods in several studies. In a comparison against synthetic (i.e., non-organic) fungicides in Michigan, sulfur application to ‘McIntosh’ and ‘Golden Delicious apples resulted in reduction of sooty blotch on fruit comparable to myclobutanil (Jones et al., 1993). Potassium bicarbonate, an organically- approved fungicide, was effective in managing SB in Switzerland, but some damage to fruit lenticels was observed (Tamm et al., 2006). Serenade® MAX, an organically- approved fungicide derived from the bacterium Bacillus subtilis, resulted in less SBFS than a non-treated control in Massachusetts, but the results were not commercially acceptable for fresh market apples (Cooley et al., 2006). In addition to the organic pesticide options to manage SBFS, cultural practices that reduce relative humidity and leaf wetness in the tree canopy may reduce incidence of the diseases even when no spray practices are used

(Ocamb-Basu et al., 1988, Cooley et al., 1997). The shift of tree spacing and training systems in the past fifty years has encouraged the development of orchard architectures that favor sunlight penetration into the canopy (Robinson, 2004b), and thus, may alleviate incidence of these diseases as fungicide options available to organic growers are limited.

Unlike diseases that cause reduction in yield or cosmetic damage to fruit, fire blight

(Erwinia amylovera (Burrill) Winslow.) is of critical concern to growers because infection may kill significant tissue in the canopy, including entire trees in severe cases (Wilcox, n.d.). In stakeholder surveys of growers and research/extension professionals, fire blight is ranked second behind apple scab as the most serious disease of apples (and pears) in the northeastern U.S. (Northeast IPM Tree Fruit Working Group, 2012). Management of fire blight in both organic and non-organic orchards includes cultural practices including

19 rootstock and scion selection for disease resistance, nutrient and management to reduce susceptible tissue, disease modelling to predict infection, pruning of infected tissue, and, when infection is predicted, application of antibiotic materials (e.g., streptomycin, oxytetracycline) (Cooley et al., 2014). Concerns with the use of synthetic antibiotics in organic systems led to their removal from the allowable materials lists by the National

Organic Program beginning in October, 2014 (Organic Materials Review Institute, 2014).

Biologically-derived pesticides for fire blight management, including fungal antagonists, yeasts, and bacterially-derived proteins, have been evaluated for efficacy with inconsistent results (Zeller, 2006). Studies in orchards in northeastern U.S. orchards have resulted in poor performance of bacterial biocontrol agents compared to antibiotics (Momol et al.,

1998), and currently there is significant research activity to improve management of this disease.

INSECT PEST MANAGEMENT IN ORGANIC APPLE ORCHARDS

Insects and other arthropod pests pose significant challenges for organic apple producers. Eighty-nine arthropod pests are listed in the Tree Fruit Field Guide to Insect,

Mite, and Disease Pests and Natural Enemies of Eastern North America (Agnello et al.,

2006), and each of them may affect both organic and non-organic orchards if not properly managed. The Northeast IPM Tree Fruit Working Group identified through researcher and stakeholder input sixteen arthropod pests of commercial importance in apple orchards

(Northeast IPM Tree Fruit Working Group, 2013). Among those pests, plum curculio (PC,

Conotrachelus nenuphar Herbst)), apple maggot (AM, Rhagoletis pomonella (Walsh)); and codling moth (CM, Cydia pomonella (L.)) were identified as the primary arthropod pests of concern by one organic orcharding proponent based in New Hampshire (Phillips,

20

2005), while European apple sawfly (EAS, Hoplocampa testudinea (Klug)), European red mite (ERM, Panonychus ulmi (Koch)), tarnished plant bug (TPB, Lygus lineolaris (Koch)), green apple aphid (GAA, Aphis pomi (DeGeer)), obliquebanded leafroller (OBLR,

Choristoneura rosaceana (Harris)), and oriental fruit moth (OFM, Grapholita molesta

(Busck)) are also considered important commercial pests in organic orchards in the region

(Peck and Merwin, 2009).

Effective options for insect management have been an impediment to organic apple production in the northeastern U.S. (Earles, 1999) and until recently, organically- acceptable insecticide options for management of CM, PC, and EAS have been particularly limited. One organically-approved insecticide, Bacillus thuringiensis, is used primarily for management of lepidopteran pests on apple. It has very few non-target effects and is relatively safe to apply, but timing its application is critical, and it is not effective against many important apple pests (Cooley et al., 2014). Another organically-approved insect management tool is the botanical insecticide pyrethrum, which is a broad-spectrum material. It has short residual activity in the orchard due to ultraviolet instability, and its lack of selectivity increases potential damage to non-target organisms including beneficial predator insect species (Peck and Merwin, 2009). Other botanical materials including sabadilla, ryania and rotenone are also broad-spectrum in activity, potentially causing high mortality to non-target organisms, and are either no longer acceptable under organic rules or no formulated products containing their active ingredients are presently on the market

(Organic Materials Review Institute, 2010).

Granulosis virus (GV) has been effective in managing CM in numerous studies

(Rashid et al., 2001, Huber and Dickler, 1977, Glen and Payne, 1984, Jaques et al., 1987).

21

However, GV is not fast-acting, and larvae may feed on fruit surfaces before dying from the virus which may cause cosmetic damage to fruit, especially at the calyx end (Glen and

Clark, 1985, Jaques et al., 1987). Spinosad, a soil bacteria-based bioinsecticide released commercially in 1997, has shown efficacy against a number of insect pests of apples

(Delate et al., 2008a, Sparks et al., 2001). Research in an organic orchard in New York concluded that currently available tools may be used to develop pest management programs for specific insect pests, but a management program for all economically important arthropod pests of apple remains difficult due to timing and efficacy issues, and would be significantly more expensive than in a non-organic system (Peck et al., 2010).

The commercialization and development of a number of new technologies have made arthropod management in organic apple systems more feasible in recent years. Kaolin clay, marketed as the commercial product Surround™ (Tessenderlo Kerley, Inc., Phoenix,

AZ), when applied as a whitewash-like coating on trees and fruit acts to deter insects or make hosts or habitat unrecognizable. It has been shown effective against arthropod pests, especially PC, in eastern U.S. orchard conditions, including Vermont, but its application may antagonize beneficial predator mite species, leading to flaring of phytophagous mite populations after use (Glenn et al., 1999, Berkett et al., 2005). Such particle film technology has exbihited non-target benefits to trees and fruit by reducing tree canopy temperature and related heat-induced stress, increasing carbon partitioning in treated trees and fruit, and improving fruit color in ‘Empire’ apples in West Virginia (Glenn et al.,

2003). However, kaolin has also been shown to reduce populations of beneficial predator mites and increase incidence of ERM and other phytophagous mites in treated orchards

(Benedict, 2005, Knight et al., 2001). The impact on orchard productivity of increased

22 phytophagous mite damage is important, because mite feeding is associated with reduced tree growth, return bloom, and fruit size, and increased preharvest fruit drop (Francesconi et al., 1996, Hall and Ferree, 1975, Lakso et al., 1996, Lienk, 1980, Marini and Pfeiffer,

1994).

HORTICULTURAL CHALLENGES IN ORGANIC APPLE ORCHARDS

In addition to challenges from disease and insect pests, crop load management and maintenance of annual bearing of trees are challenging in organic orchards (Moran, 2007).

Naturally, apple trees tend to produce large crops of relatively small fruit every other year

(Jonkers, 1979). This cropping pattern is not desirable for commercial apple growers who require annual crops to maintain cash flow, and because heavy crops tend to consist of small apples that are not profitable in the fresh market. Apple growers routinely practice fruit thinning during early fruit development from petal fall through 20 mm fruit size to reduce crop load and apportion more photosynthate and other resources to remaining fruit while promoting development of adequate numbers of fruit buds for the following year

(Byers, 2003).

One potential benefit of the phytotoxic response of lime sulfur is its effect on fruit set and thinning. In the past there has been a lack of efficient or cost-effective thinning agents available to certified organic growers (Andrews et al., 2001). Many growers rely upon hand labor to thin organic apples which is very expensive and difficult to complete in the narrow window between bloom and 20 mm fruit size. Thus, use of organically- approved spray materials that promote apple thinning are an important practice used in organic orchards. Applications of lime sulfur at bloom and petal fall have shown comparable thinning response to the standard plant growth regulator carbaryl which is used

23 in non-organic apple production systems (Noordijk and Schupp, 2003, Stopar, 2004). Two modes of action are implicated in the thinning effects of lime sulfur. Application during bloom has resulted in reduced pollen tube growth and lower seed count in apples, which decreases fruit set and increases thinning (McArtney et al., 2006). Furthermore, reduction in net photosynthesis when lime sulfur is applied during and after bloom has resulted in reduced fruit number due to increased deficits of photosynthates which the plant requires to set fruit (McArtney et al., 2006, Hyre, 1939, McAfee and Rom, 2006). These modes of action are consistent with those of some thinning agents used in non-organic programs

(Looney, 1986, Wertheim, 2000). However, lime sulfur alone may not adequately thin a heavy crop, and follow-up hand thinning is often necessary. In one multi-year study in

Washington, unsatisfactory thinning response from lime sulfur application resulted in uneven yields that reduced organic orchard profitability (Peck et al., 2006).

Production of apples in a modern, high-efficiency orchard system requires that trees maintain adequate annual vegetative growth. As orchard systems have evolved to include trees on dwarfing rootstocks planted at higher densities, benefits include greater yield, shorter time to reach production and orchard profitability, and increased fruit quality. The primary drawback to higher density planting systems is increased establishment cost, but this is meant to be offset by increased precocity and productivity of the planting in the initial years (Robinson, 2006). Therefore, practices that potentially reduce tree growth and thus negatively impact tree establishment, such as the use of sulfur and lime sulfur applications for disease management or thinning activities, may decrease the profitability of organic high density apple orchards. Typically in commercial, high density orchards, vegetative shoot growth of 50 cm is desired in the first year after planting, and 75-100 cm

24 leader growth in the second and third years after planting in order to establish the orchard for maximum productivity (Robinson, 2007). Should trees not generate adequate growth to fill their allotted space by the third or fourth year after planting, economic performance of the orchard is likely to suffer (Robinson, 2005). One proxy measure of tree growth is trunk cross-sectional area (TCSA), which is easily measured and correlates with total tree canopy size (Westwood and Roberts, 1970). In one Washington study, organically- managed apple trees had lower TCSA than non-organic trees and those managed with integrated fruit production (IFP, a hybrid of organic and conventional systems used in the study) in the first year after planting, but by the second and later years no differences were found between the production systems (Andrews et al., 2001). However, the growing conditions in eastern Washington are very different from the northeastern U.S. In a New

York study of organic and IFP orchard management systems on ‘Liberty’, no differences were found in TCSA between the systems (Peck et al., 2010)

Maintenance of adequate and tree nutrition are critical to ensure long- term orchard productivity. Standard fertility programs are well-established for non-organic apple systems in the northeastern U.S. (Stiles and Reid, 1991), but may not accurately reflect the needs of an organic planting. Apple orchards require adequate supplies of macro- and micronutrients to complete biological processes including tree growth, fruit bud and blossom development, fruit set and maturity, and development of winter hardiness.

Nitrogen (N) is used as the primary building block for all plant parts, and is an important factor in vegetative growth, fruit bud development, cold hardiness, and fruit quality.

Potassium (K) serves as an enzyme activator and is used in the formation and translocation of sugars, proteins, and plant hormones. Phosphorus is an important component in cellular

25 energy transfer and storage, as well as in formation of nucleic acids. Plants use calcium

(Ca) as a component of cell wall formation, which helps to maintain fruit firmness and fruit quality in apple. Magnesium (Mg), manganese (Mn), and iron (Fe) are important components in chlorophyll production, and serve as enzyme components or activators in plants. Boron (B) is required for pollen tube development for fruit set as well as for translocation of substances in plant cells. Copper (Cu) and zinc (Zn) are important components of plant enzymes and assist in fruit set and cold hardiness. Complete tree nutrition requires that mineral nutrients be available at optimum levels. Furthermore, excess amounts can potentially be as harmful as deficiencies, and that relative levels of mineral nutrients to one another must be satisfied to avoid inter-nutrient competition and to and maintain adequate activity between related nutrients. Soil acidity (pH) is highly correlated with the availability of mineral nutrients to plants in a usable form (Garcia,

1998).

Nutrients can be supplied by plant tissue and soil reserves, but amendments are often required to maintain adequate levels in the tree. Orchard fertility programs are tailored based on analyses of soil and foliar tissue samples, and when low or deficient levels are measured, soil amendments and/or foliar applications are used to maintain soil and plant fertility. Nitrogen is one of the most commonly applied nutrients in orchards to ensure adequate vegetative growth, and is supplied via soil and foliar application. Potassium is required by apple trees in relatively large amounts and often is the most applied nutrient on a kg/ha basis, and is typically soil-applied in orchards. Phosphorus is rarely deficient in

New England apple orchards. However, growers typically must provide calcium to New

England orchards on an annual basis. Calcium is often soil-applied through lime

26 applications used to correct or maintain soil pH, but large amounts of lime can only be incorporated during site preparation before trees are planted. After planting, relatively smaller amounts of calcium may be applied to the soil, as well as in foliar sprays.

Magnesium supplements are required in many commercial orchards, and can be supplied via soil-applied materials or through foliar sprays to correct short-term deficiencies. Boron is frequently deficient in orchard soils and is applied to soil and foliage, but growers must be cautious because excess boron levels in tree can cause phytotoxicity. Copper, zinc, and manganese may require supplementation in individual orchards, and are commonly applied to soil or foliage. Generally, maintenance of soil fertility is important in long-term orchard maintenance, whereas foliar sprays are used to correct for short-term deficiencies or when small quantities of materials are required (Stiles and Reid, 1991).

Fertilizer materials available for organic apple production are limited, and tend to be more expensive than materials used in non-organic systems (Peck and Merwin, 2008).

Most studies on organic orchard fertility in North America have been in semi-arid, western production regions with very different soil and climactic conditions from the northeastern

U.S., so applicability of findings may be limited in New England. Soil fertility needs, especially nitrogen, can be addressed with organic amendments including compost, fish products, blood meal and organic sources (Hoagland et al., 2008, Merwin and Peck, 2009,

Yao et al., 2005), but organic certification rules limit over-application of nutrients to soils

(National Organic Standards Board (NOSB), 1995). are often used in organic production systems, but their high cost, relatively low nutrient content, weight and bulk, and potential for over application of phosphorous (a mineral nutrient that is highly concentrated in animal and whose runoff from agricultural fields causes

27 significant water pollution) prevents their use in regular annual fertility programs

(Carpenter et al., 1998, Travis et al., 2003). Due to their relatively low nutrient content compared to chemical and the amounts required to address common fertility needs, application of large amounts of compost into the orchard tends to be expensive, plant response is slow, and adequate incorporation of the material into the root zone is difficult after trees have been planted (Swezey, 2000). Organically-approved, rock-based soil-applied mineral materials such as greensand and azomite have low plant availability of individual elements including N, P, K, Mg, and Ca, again limiting their use in maintaining complete tree nutrition. For these reasons and because many mineral micronutrients are needed in such small quantities and are easily absorbed by foliage, organic apple growers often include applications of sprayable materials such as liquid fish- products, soluble kelp powders, and micronutrient products in their fertility programs

(Mengel, 2001). Other fertilizers are available for certified organic growers to address specific mineral requirements including calcium, boron, magnesium, and manganese if foliar analysis indicates deficiencies (Peck and Merwin, 2009). Although acceptable organic fertility inputs may cost more than non-organically approved alternatives, their overall availability is not generally considered a significant deterrent to adoption of organic orchard management (Schupp, 2004). However, mineral nutrient deficiencies can affect orchard performance negatively in organic systems just as in non-organic ones. In one

Washington study, lower levels of zinc in foliar tissue samples in organically-managed trees was suggested as one potential factor in reduced crop yield compared to a non-organic standard (Peck et al., 2006).

28

Some proponents of organic apple systems suggest that conventional, non-organic fertility recommendations are not applicable to organic conditions since the focus of organic production is on building healthy, biologically active soil that makes plants more resilient to stresses and offers a more balanced environment than in non-organic programs where individual nutrient values are studied to develop comprehensive nutrition plans

(Phillips, 2005). The concept of managing soil health to improve , as opposed to managing for distinct mineral nutrients based on soil or plant tissue analyses, is inherent in the definition of organic production systems that “use…cover crops, green manures, animal manures and crop rotations to fertilize the soil, maximize biological activity and maintain long-term soil health” (National Organic Standards Board (NOSB),

1995). Management of orchard soil health includes both nutrient applications and groundcover management systems, the latter including practices typically used to manage under-tree weeds but which also affect orchard productivity complementary to orchard nutrient management.

Several studies of organic apple production systems in the U.S. have looked at impacts of organic management on soil quality. In a four-year study in eastern Washington state, organically-managed plots had lower soil bulk density and improved soil biology versus a conventional treatment (Glover et al., 2000). In that study, organic and mechanical tillage were used to manage weeds, compared to use of in the conventional treatment. Another two-year study of groundcover management treatments in Washington found differences attributable to the practices used to manage the orchard understory (Hoagland et al., 2008). Mechanical tillage resulted in adequate leaf N, but soil biological activity was not improved over the other systems. ‘Living ’ cover crops

29 improved soil biological activity but trees grew less than in other systems, presumably because groundcovers competed with trees for N and water. Wood chip mulch resulted in improved tree growth but no improvement in soil biological activity. Organically-approved herbicides performed poorly and did not improve tree growth or soil biology. In another groundcover management study conducted in Washington, wood chip mulch treatments were associated with increased N partitioning and dry matter weight in trees compared to non-mulched treatments (TerAvest et al., 2010). The specific soil management practices used in organic production systems thus are more nuanced in their effects on orchard productivity and multiple practices will likely be required in any given orchard system.

Crop yield of organic orchards has been compared to non-organic orchards in several studies. In Washington, studies of organic vs. non-organic orchards have shown conflicting results in terms of crop yield. In a two-year study of top-grafted ‘Galaxy

Gala’/’EMLA 9’ apples, an organically-managed treatment had approximately one-third the yield of the non-organic treatment in one year, but in the following year, the organic treatment had nearly 60% greater yield (Peck et al., 2006). In that study, crop yield from organic trees ranged from 15.28-56.50 Mg*ha-1 (324-1188 bushels*ac-1) over the two years. Cumulative yields of organic and non-organic orchard treatments were not statistically different in a five-year study also conducted in eastern Washington, with annual yields from organic trees during full production ranging from 51.2-75.9 Mg*ha-1

(1086-1611 bushels*ac-1) (Reganold et al., 2001). However, growing conditions in arid eastern Washington are conducive to organic apple production because disease and insect pests are of far less concern than in the northeastern U.S. (Hinman and Ames, 2011). In a multi-year study of organic vs. non-organic apple management of ‘Liberty’ (a scab-

30 resistant cultivar) /’M.9’ apples in New York, a statistically significant difference in crop yield was only observed in one of four years, when non-organic trees produced greater yield than the organic treatment (Peck et al., 2010). Harvested crop yield during that study

(2004-2007) ranged approximately from 30-50 Mg*ha-1 (637-1061 bushels*ac-1) for all treatments. However, none of those studies tested commercially popular, apple scab- susceptible cultivars grown under organic management in the northeastern U.S. where weather conditions are conducive to development of the disease. Because of the phytotoxic nature of sulfur and lime sulfur that are used for apple cab management, a negative response for crop yield has been observed in several studies. In a single-season evaluation the effects of organically-acceptable sulfur-based spray programs on multiple cultivars in New York, the organic apples yielded 409 bushels per acre (19.25 Mg/ha) vs 861 bushels per acre

(40.53 Mg/ha) in the non-organic treatment (Rosenberger and Jentsch, 2006). Fruit weight, a measure of marketable fruit size, was also lower in the organic treatment.

ECONOMIC EVALUATIONS OF ORGANIC APPLE PRODUCTION SYSTEMS

Assessing the overall performance of commercial orchard systems is important in determining the profitability of the . Establishing a commercial apple orchard involves significant, long-term economic risk that must be managed by the type of the orchard established and subsequent management and marketing of the crop in later years.

The primary factor in deciding what type of orchard to plant is the long-term return on the investment (ROI) required to establish and maintain the orchard . ROI for an orchard will be affected by the initial establishment cost, precocity of the trees (i.e., the time in years required to bring the orchard to marketable production), marketable crop yield over time, and the quality of the fruit produced in the system. Other factors that affect the ROI include

31 the technical expertise required to maintain the orchard , social factors that affect marketing potential, and economic factors both within the farm operation and in the marketplace.

Establishment costs for top-grafting old orchards, where new scions are grafted to tree trunks in an existing orchard to change to a preferred apple cultivar, and establishing new orchard with nursery trees, vary considerably based on a number of factors. A top- grafted orchard can be relatively inexpensive to establish, because new trees do not need to be purchased, and old trees are not required to be removed nor land prepared for 1-2 seasons prior to replanting to avoid poor growth from replant disease, a biotic condition that requires that land in apples be left fallow or actively remediated to reduce soil pathogens that weaken young trees (Pruyne et al., 1994, Parker, 1966). Direct costs for establishing a top-grafted planting include purchase of scion material, if required, although many growers utilize their own wood or obtain dormant from other growers.

Labor for grafting operations includes cutting the tops of trees back to a roughly one meter high stump, and removal of that wood from the orchard; grafting of trees in the spring of the year of establishment; and management of developing growth during the initial and subsequent years of establishment. Because top-grafted trees typically occur in orchards that are in full fruit production, less loss of crop during the establishment years is experienced than if the trees were completely removed for a new orchard. Trees can even bear a small crop of fruit on the nurse limbs left in the grafted tree to support tree growth during initial establishment in the year of grafting. By Year 2, a small crop is typically produced on new scion growth, with good production by Year 3. For top-grafting to produce a long-term, profitable orchard, it is critical that the trees to be top-grafted are in good health with adequate tree spacing and good soil fertility. Therefore, top-grafting of

32 orchards is typically done on healthy, good-yielding trees where a change in fruit cultivar is desired to take advantage of better prices or marketability of the new cultivar. Little research has been conducted on the performance of established orchards that have been top-grafted to new cultivars.

On the other hand, planting a new orchard require greater costs to establish.

Assuming that the grower is planting the new orchard on ground that presently has an older, established planting, those trees, including stumps and roots, must be removed (Barden and

Neilsen, 2003). The site must be plowed down, subsoil tilled, soil tests collected and pH and nutrients adjusted as necessary. The site must then be left fallow, or more commonly cover cropped for at least one year to reduce populations of nematodes and other microorganisms that contribute to apple replant disease. During these one to two years, the grower does not see any production from the orchard. In the planting year, significant costs are incurred, including purchase of trees, trellis, and irrigation materials, as well as the labor required for their installation. The establishment costs during the year of planting are directly related to the tree density of the new orchard. Lower density planting systems

(<1000 trees per hectare) have lower establishment costs than higher density plantings because fewer trees need to be purchased, planting labor is reduced, trellising may not be required, and wider row spacing allows for less site work and reduced irrigation supplies.

As tree density increases, direct costs of purchased trees rises, and trellis and irrigation supplies, plus installation labor also increase. Direct installation costs for newly planted orchards can range from less than $15,000 per hectare for lower density systems to upwards of $50,000 per acre for high density systems of 2500 trees or more per hectare (Robinson,

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2006). These initial establishment costs must be offset over time by the productivity of the orchard to ensure adequate ROI to the grower.

The primary factor affecting the profitability of an orchard is precocity (Robinson,

2006). In order to achieve high precocity, a grower must have the management knowledge and skill to properly train trees in the initial establishment years. Although no data were found on the precocity of top-grafted apple trees in a review of the literature, fruit growers in Vermont report that top-grafted trees in commercial orchards tend to produce a small crop in Year 2, with marketable yield beginning in the third season and increasing until the trees reach mature size around Years 5-7 (B. Hodges, R. Allen, pers. comm.). Improved tree precocity is a primary benefit of top-grafted orchards. Precocity of newly planted orchards is dependent primarily on rootstock and tree density, with high density (>1875 trees per hectare) plantings on dwarfing rootstocks having production in the second or third year, and significant marketable production achieved in Years 3-5 (Robinson, 2003). As tree density decreases and rootstocks shift toward semi-dwarfing types, precocity decreases. Medium density orchards of 625-1000 trees per hectare tend to begin production in Years 3-5, with significant marketable production in Years 5-7. Although less precocious than high density systems, these orchards with medium density of trees are popular in Vermont, and their precocity is preferable to the 10-12 years required to achieve production that were common in older, low-density (<250 trees per hectare) orchards planted on non-dwarfing rootstocks prior to the 1960s (VTFGA, 2011).

Given that an orchard is a long-term investment of 15 years or more, total system profitability must also be based on long-term yield of marketable crops from the orchard.

Assuming that trees are healthy, cumulative yield over time is most directly related to tree

34 density, with precocity and scion cultivar also significant factors (Robinson, 2003). This is where the increased crop yield of high density planting systems offsets their increased establishment costs. Considerable research has shown an increase in cumulative yield as tree density increases, but those yields can be reduced if environmental or other crop losses occur in the orchard or if the orchard is not managed properly (Funt et al., 1982, Robinson et al., 2007, Weber, 2000, Hampson et al., 2002). Therefore, the technical management skill of the grower is important to ensure that potential yields will be realized for an orchard. In lower density systems where total yield is achieved with larger per-tree yields on fewer trees per hectare, any tree loss can result in significant loss of production. Top- grafted orchards, because of the extreme stress placed on trees when grafted and the need to support vigorous growth from the new scion in early years, often experience some tree loss in the orchard (Blazek et al., 2002). As tree number declines, total profitability of the orchard will also decline. It is also important to note that most modern apple production systems assume a twenty-year production period from the orchard, and if an orchard was established for a significant portion of that time before top-grafting, the total effective lifespan of the newly top-grafted trees may be reduced as compared to a newly planted orchard .

In addition to total yield from an orchard, the quality of fruit produced is a major factor in the profitability of the system. Small, poorly colored fruit which are the result of growing in excessively vegetative, shaded canopies are worth less on the fresh market than large, well-colored fruit grown on trees with good light penetration into the canopy as is experienced in higher density systems (Robinson, 2003). Orchard maintenance costs are also reduced in higher density training systems, especially pruning and spray material costs

35 per bushel of fruit produced. If high total production of better quality apples can be achieved in high density orchards, the increased establishment costs may be offset over the life of the orchard.

There are many economic factors that impact the ROI of an orchard system. The marketability of apple cultivars chosen for the orchard is critical in order to sell the fruit at a profitable price. In the top-grafted orchard, the grower chose to renew the trees specifically to change cultivar, just as specific cultivars were chosen in the newly planted orchard. Customers must be receptive to purchasing the fruit of the chosen cultivar for the life of the orchard, which may be twenty years or greater. It does no good for a grower to grow maximum yield of a cultivar that he/she cannot sell for a profit. If the fruit are to be marketed wholesale, the price received for fruit is usually not determined by the grower but rather set by a broker or the end retailer. High wholesale prices received for new cultivars tend to decline over time as production increases and competition from the next new apple takes their place in the market (Carew and Smith, 2004). Organic growers also must expect a price premium for their fruit to offset the increased production costs and possibly lower yields experienced under that management system. In some cases, price increases for organic fruit have not been as great as expected, and customers may shift purchasing preference to non-organic apples if fruit quality is substantially lower for organic apples or price difference becomes too great (Loureiro et al., 2001). In Vermont, however, significant demand for organic apples has been demonstrated, along with consumer willingness to pay price premiums for local organic fruit (Wang et al., 2010). In a retail, pick-your-own orchard, customers may also be resistant to a different customer experience in modern high-density systems that do not resemble the sprawling, spacious

36 orchards often envisioned as a setting for a family outing. Retail growers also must gauge customer willingness to pay when setting prices, and must contend with additional costs and management concerns associated with allowing public access to the farm.

Access to capital will be an especially important consideration when planting an orchard. If a grower cannot self-fund or borrow to cover high early establishment costs, then the installation of high density systems will likely not be an option. However, growers considering installation of any orchard must consider the long-term profitability of the system as well as initial investment required, and accurate information may make lenders more willing to loan capital. By measuring ROI on a net present value (NPV) basis, growers and lenders can assess the potential ROI similar to other financial investments.

NPV is an adjustment technique that considers the long-term profitability of an investment against a chosen potential rate of return (Khera et al., 1980). For example, a low-risk mutual fund may return 6% annually over a ten-year period. NPV allows for assessment of expected orchard performance from a set investment amount versus placing those funds in the investment used for comparison, and compares that value to the present value of money.

NPV analyses have been conducted on modern high density orchard systems in recent years. Tree density and planting system have been significant factors in reducing break-even period for NPV, and in New York, higher density systems with 2000-3000 trees per hectare have performed best in this regard, with 13-14 years required before breaking even on investment (Robinson, 2003). However, total orchard system profitability was most affected by the price received for fruit and the total yield of the orchard (Robinson et al., 2007). There have been few studies examining the economics of top-grafted orchards, but one experiment in the Czech Republic found an eight-year break-even period

37 under the economic and horticultural conditions present in that country. In addition to yield and fruit price, tree death in the top-grafted orchards was a significant factor in reducing the potential profitability of the system (Blazek et al., 2002). Lower price received for fruit than projected, potential reduced total yield for the orchard system, and tree death or decline may therefore reduce profitability of both top-grafted and newly planted orchards.

Studies of projected long-term economic performance of orchard systems have found varying break-even points where initial installation and management costs were recouped via projected sales of harvested fruit. In an analysis of non-organic, high density orchard systems with different tree training systems conducted by researchers at Cornell

University (Robinson et al., 2007), the break-even point varied between 12 years for a slender axis training system (2244 trees/ha), 13 years for tall spindle (3312 trees/ha), 14 years for super spindle and vertical axis training systems (5382 and 1538 trees/ha, respectively), and 17 years for the lowest density slender pyramid system (840 trees/ha).

In that analysis, land price, tree cost, fruit price, and cost of trellis system were significant factors in overall profitability. NPV of the orchard systems after 20 years was projected at

$23,900, $23,400, $19,200, $17,100, and $9,000/ ha for slender axis, tall spindle, super spindle, vertical axis, and the lowest density slender pyramid systems, respectively. Fruit price was based on commodity apple cultivars sold on the wholesale market, and thus may not reflect prices received for organic fruit or fruit sold through direct retail markets. In a comparison of projected economic performance of high density organic and non-organic orchards (2240 trees/ha) in Washington, positive cash flow was realized in the sixth year in both systems, with break-even points for organic and non-organic systems at nine and fifteen years, respectively (Andrews et al., 2001, Reganold et al., 2001). An important

38 consideration in those studies is that the environmental conditions in eastern Washington are not conducive to disease development, and the insect complex is greatly reduced compared to the northeastern U.S., so production costs for organic orchards are likely to differ significantly between the regions (Hinman and Ames, 2011). Another factor which affected the economic performance of those orchards was the assumption that organic fruit would require a price premium of 12% over the non-organic fruit.

A four-year comparison of organic and non-organic ‘Liberty’ apple trees, planted at 1537 trees/ha, estimated that the wholesale market value of organic fruit was lower than non-organic fruit in three of the years (Peck et al., 2010). Mean estimated revenue across the four years was $12,616/ha and $13,971/ha for organic and non-organic orchards, respectively. The projections in that study also assumed a price premium of 56% for organic fruit. Total crop value was reduced because many fruit were small or blemished and therefore were assumed to be sold to lower-value processing markets or culled with no associated price value at all. A separate analysis was performed assuming that fruit were sold direct to retail markets with the same price premium for organic fruit. Under that scenario, mean revenue was $52,343/ha and $49,279/ha for organic and non-organic fruit, respectively. Fruit were sorted into only two categories based on size, with fruit weighing

122 g or more sorted into fresh sales and all fruit weighing less than 122 g assigned a processing grade. Fruit defects and quality were not considered in this analysis, nor was

NPV or break-even point determined.

Production costs in an apple scab susceptible orchard in wet regions of the U.S. are an important consideration when evaluating potential profitability of the enterprise.

Although organic fungicide costs in simple dollars per pound may be lower than for many

39 synthetic fungicides, total application costs tend to be greater for organically-acceptable sulfur or copper-based fungicides because they are typically applied at higher rates more frequently than their synthetic counterparts (Ellis et al., 1998). In a one-year comparison of organic and non-organic spray programs including scab fungicides in New York, total spray material and application costs were $2,897/ha for the organic treatment compared to

$1,605/ha for the non-organic treatment. Because the organic treatment had significantly lower yield than the non-organic treatment, pest management costs per bushel (18.1 kg) of fruit were $2.98 and $0.76, respectively (Rosenberger and Jentsch, 2006). In eastern

Washington, where fungal disease pressures are low and organic apple production is a more common system, one study found that organic, integrated, and conventional orchards were all not profitable until their fifth year, with higher input and labor costs for the organic treatment (Andrews et al., 2001).

Economic modelling of orchard systems has been conducted to some degree, but most studies have evaluated modelling tools on theoretical orchards or on preliminary data to assess factors that affect potential profitability. In one Swiss study, the authors used the

‘Arbokost’ modelling tool for profitability assessment of organic and ‘integrated’ orchards

(Bravin et al., 2008). Modelled variables for labor, production costs, and income included

‘pessimistic’ and ‘optimistic’ scenarios, rather than actual long-term production data.

Given those scenarios, most orchards had negative NPV after 15 years, but effects of biological factors on orchard profitability were not evaluated. Numerous Extension publications have provided enterprise budgets for apple producers in various regions, however, they typically project profitability from Year 0 based on yield and cost assumptions (Bechtel et al., 1995, Robinson et al., 2007, Rowles et al., 2001, White, 2000).

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Each of those publications included outward projections based on yield and fruit quality standards commonly achievable by commercial non-organic producers in their regions.

However, because organic orchard systems in the northeastern U.S. may have greater incidence of pest damage and lower yield than non-organic orchards (Rosenberger and

Jentsch, 2006, Hinman and Ames, 2011), it is important to determine biologically- significant orchard indicators, e.g., tree growth, yield, disease and arthropod pest incidence, and abiotic fruit quality factors, that may be addressed to improve their profitability.

As mentioned previously, apples are an important component of New England's diversified agriculture. Although there is significant interest in organic production, there are very few organic apple orchards in New England, in part, because of the challenges associated with the traditional apple cultivar grown (‘McIntosh’). However, because of recent shifts in consumer preference for newer cultivars, growers are planting different apple cultivars. Growers want to know what the potential is for sustainable and profitable organic production with the newer apple cultivars that are being planted in the region. The

OrganicA Project was initiated in 2006 to holistically examine the opportunities and challenges of organic production within the two major orchard systems growers were using to change to new cultivars and with five of the top apple cultivars that growers identified as important to the future of the industry. The long-term goal of this multi-state, multidisciplinary project was to enhance adoption of organic apple production in New

England through research that advanced the scientific knowledge base and provided practical information to apple growers that would aid them in decision-making on which cultivar(s) and orchard establishment system would be best for their organic enterprise.

Research results from the project are reported herein.

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THE ORGANICA PROJECT: A GENERAL OUTLINE FOR THIS DISSERTATION

In response to changes in cultivars in commercial orchards and development of new pest and crop load management tools that may potentially improve the feasibility of organic apple production in New England., a USDA-funded organic apple production research and extension project (OrganicA) was initiated in 2006. Led by Dr. Lorraine Berkett at the

University of Vermont with investigating faculty from that institution as well as the

University of Arkansas and the University of Maine, the author of this dissertation served as primary field technician in the associated Vermont orchards, completed an M.S. degree while conducting an assessment of kelp extract biostimulants in one orchard, and with this report, will complete a Ph.D. with the project.

In 2006, research knowledge on potential organic alternatives in apple production was at a point where it needed to be integrated into organic apple production systems and evaluated holistically, including an economic analysis of potential economic costs, returns, and risks associated with the different cultivars being planted and the production systems growers were using to switch to new apple cultivars. Thus, after extensive stakeholder input, researchers at the Universities of Vermont, Arkansas, and Maine proposed a multi- disciplinary, multi-state research project (OrganicA Project) in 2006 to research the opportunities and challenges of organic production within the two major production systems growers were using to change to new cultivars and with five of the top apple cultivars that growers identified as important to the future of the industry. The orchard systems were: (i) a new orchard planted with young trees purchased from a nursery and (ii) a “top-grafted” orchard, i.e., an established, older orchard onto which new cultivars are

56 grafted. The cultivars studied in replicated plots in each orchard system were: ‘Zestar!’,

‘Ginger Gold’, ‘Honeycrisp’, ‘Macoun’, and ‘Liberty’.

The OrganicA Project was submitted to the USDA Integrated Organic Program

(IOP) in 2006 as a project that would require six to nine years to complete. The USDA

IOP approved the project in 2006 and provided funding for the first three years (“Using

‘New’ Alternatives to Enhance Adoption of Organic Apple Production through Integrated

Research, Education, and Extension”, USDA CSREES 2006-51300-03478). The second, multi-year phase of the OrganicA Project was funded by the USDA Organic Research &

Extension Initiative and was entitled: “Using ‘New’ Alternatives to Enhance Adoption of

Organic Apple Production through Integrated Research and Extension” (USDA CSREES

2009-51300-05530). The rationale and objectives of each grant proposal are listed in

Appendix 1 along with the list of investigators.

In 2006, research was initiated at the University of Vermont Horticulture Research

Center in South Burlington, VT to comprehensively evaluate the five apple cultivars of

‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’, ‘Macoun’, and ‘Zestar!’ over eight growing seasons in the two orchard production systems. Both orchards were managed organically from the outset of the project, and received organic certification in 2008. Orchard 1 was planted on prepared, bare ground with nursery-grown trees in 2006 with a high-density vertical axis training system with single-wire trellis and individual conduit support poles for each tree. In Orchard 2, the five cultivars were top-grafted in 2006 onto an existing freestanding semi-dwarf orchard originally planted in 1988.

In the following chapters, the long-term evaluation of the five cultivars for tree growth; crop yield; disease and arthropod pest incidence; and economic return is

57 summarized over the duration of the project. As such, the data presented generally consist of grand means of parameters assessed annually over either six or eight years, as applicable.

For most parameters, annual data are not presented unless it is relevant to a discussion.

Nearly all measured parameters had a cultivar x year effect significant at α=0.05, and a deeper discussion of each parameter among the cultivars for each year may be warranted, but that focus is largely beyond the scope of this summary.

Each chapter has been submitted and accepted for presentation at the International

Symposium on Innovation in Integrated and Organic Horticulture in Avignon, France in

June 2015, and is written for publication in the International Society for Horticultural

Science Journal Acta Hort.iculturae. In Chapter 2, tree growth, survival, and crop yield are summarized for the fruit producing years 2008-2013. Disease and insect pest incidence is summarized for those same years in Chapter 3. In Chapter 4, economic performance from the time of orchard establishment including: actual input, labor, and machinery costs; cumulative income; and net present value of each cultivar in both orchards including twenty-year projections is summarized. The final chapter includes a summary of the results of the project overall. Because of length and formatting limitations in Acta Hort.iculturae more detailed exploration of some of the results described in Chapters 2-4 is presented in the last chapter.

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CHAPTER 2: JOURNAL ARTICLE- TREE GROWTH AND CROP YIELD OF FIVE CULTIVARS IN TWO ORGANIC APPLE ORCHARD SYSTEMS IN VERMONT, USA, 2006-2013

Terence L. Bradshaw1, Lorraine P. Berkett1, Heather M. Darby1, Robert L. Parsons1, Renae E. Moran2, M. Elena Garcia3, Sarah L. Kingsley-Richards1, Morgan C. Griffith1, Sidney C. Bosworth1, and Josef H. Gorres1 1University of Vermont, 2University of Maine, 3University of Arkansas

Keywords:

Malus ×domestica, ‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’, ‘Macoun’, ‘Zestar!’, cultivar evaluation, top-grafting

ABSTRACT

Adequate tree growth and crop yield are essential to the long-term success of orchard systems and these are often challenges when systems are managed organically in the northeastern U.S. The objective of this project was to evaluate horticultural performance of five apple cultivars (‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’,

‘Macoun’, and ‘Zestar!’) grown under organic management in both a newly planted orchard (Orchard 1) and in a top-grafted established orchard (Orchard 2). Results summarize tree growth and crop yield of each cultivar in both production systems over eight seasons from 2006-2013. There were no differences in tree survival among the cultivars in Orchard 1, where survival ranged from 97.8% to 100%. However, only 65.8% of ‘Macoun’ and 63.2% of ‘Zestar!’ trees survived in Orchard 2. There were cultivar differences in tree growth parameters within the two orchard systems.

However, in both orchards, ‘Ginger Gold’ had the greatest, or was among the cultivars with the greatest shoot growth, tree height, and tree width. ‘Ginger Gold’

59 was also among the highest-yielding cultivars in all years in Orchard 1, and in three of six years in Orchard 2. ‘Macoun’ had among the lowest crop yield in most years in both orchards. ‘Ginger Gold’ and ‘Honeycrisp’ had among the highest cumulative yield per tree in Orchard 1. ‘Ginger Gold’ in Orchard 2 had the highest cumulative yield per tree of all cultivars. These results combined with analyses of disease and arthropod incidence and economic performance comparing the five cultivars within each orchard system will aid growers in their decision-making to select cultivar(s) and orchard establishment methods for an organic production system.

INTRODUCTION

Although apples are an important specialty crop in Vermont, organic management is used in a small proportion of the region’s orchards, and no organic apples from the state were counted in a comprehensive industry survey (USDA Economic Research Service,

2013). Systems-level research on organic apple production in the U.S. has been limited to dissimilar climatic regions to the northeastern United States (U.S.) with different pest pressures, e.g., Washington State (Andrews et al., 2001, Reganold et al., 2001, Peck et al.,

2006, Kirby and Granatstein, 2012) or in New York on a cultivar resistant to apple scab which is not widely planted and has very different cultural management needs from cultivars that are commonly planted in the region (Peck and Merwin, 2008, Peck et al.,

2009, Peck et al., 2010). No long-term research in the northeastern U.S. has been conducted to assess cultivar performance of trees established under organic management from the time of planting.

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Tree survival, growth, and crop yield are important measures of performance used in evaluating apple cultivars and orchard systems. In this long-term study, those horticultural parameters of five apple cultivars identified by Vermont growers as important to their industry grown under organic management since orchard establishment were assessed in two orchard production systems: a newly planted orchard and a top-grafted established orchard. Results presented are an overall summary of horticultural performance over eight years (2006-2013). These results plus analyses of arthropod and disease incidence and the economic performance of the five cultivars within each orchard system, which will be reported in separate articles (Bradshaw et al., 2015a, Bradshaw et al., 2015c), will provide apple growers with comprehensive information to aid in their decision-making as to which cultivar(s) and system would fit best into their organic enterprise.

MATERIALS AND METHODS

In 2006, two apple orchards were established at the University of Vermont

Horticulture Research and Education Center in South Burlington, VT (lat. 44.43162, long.

-73.20186, USDA hardiness zone 5a, Köppen-Geiger classification Dfb) as part of the

Organic Apple Research and Demonstration (OrganicA) Project (Berkett et al., 2009a,

Berkett et al., 2006). The orchard soil is a Windsor Adams loamy sand, characterized by a coarse, sandy texture, extremely good internal water drainage, low organic matter, and generally low nutrient availability and cation exchange capacity.

Orchard 1 was planted in April 2006 with the cultivars ‘Ginger Gold’, ‘Liberty’,

‘Macoun’, and ‘Zestar!’ on Bud. 9 rootstock and ‘Honeycrisp’ on M.26. rootstock at a tree spacing of 1.5 m x 4.6 m and trained to a vertical axis system. Each cultivar was replicated

15 times in a completely randomized design with three-tree replications. A previous

61 orchard was removed from the site in 2003 and site preparation included lime application and cover cropping for two years following commercial recommendations (Peck and

Merwin, 2009, Pruyne et al., 1994, Robinson, 2005). To minimize variation in original tree size and quality, all shoots were removed and trees pruned to 1 m in height at planting.

Orchard 2 was an existing orchard planted in 1988 with ‘McIntosh’ and ‘Liberty’ trees on

M.26 rootstock which was top-grafted in April 2006 to the same five cultivars as were planted in Orchard 1. New cultivars were grafted in a randomized complete block design with two-tree replications, eight replications on ‘Liberty’ interstock and eleven on

‘McIntosh’, to block any effect of the original cultivar on new scion growth. Trees were trained to a free-standing central leader system. Block effects from the original scion cultivar were only observed for trunk cross sectional area (TCSA) in 2011, 2012, and 2013

(p= 0.03, 0.05, & 0.01, respectively) during the study, and were tangential to the overall focus of the research, so will not be further discussed. All data in this orchard were pooled to include both interstocks within the overall cultivar data.

Standard organic management practices including: groundcover management via mowing, mulching, and mechanical and hand tillage (Orchard 1) and mowing (Orchard 2); tree training and pruning; and application of mineral nutrient materials were applied during each growing season according to standard organic commercial recommendations (Peck and Merwin, 2009, Cooley et al., 2014). Soil moisture tension was measured weekly

(Watermark Soil Moisture Sensor, Spectrum Technologies, Inc., Plainfield, IL) and drip irrigation applied if below 30 cbars. Orchard sanitation practices including removal of fruit dropped on the orchard floor prior to harvest, leaf shredding in autumn or early spring, removal of diseased and dead wood, and pruning to an open canopy were performed

62 annually. Hourly on-site weather data including temperature, humidity, precipitation, wind speed and direction, solar radiation, and leaf wetness were recorded continuously during the study period using an automated weather station (Davis Vantage Pro Plus, Model #

6162, Davis Instruments Corp., Hayward, CA from 2006-2009; Rainwise MK-II,

Rainwise, Inc., Trenton, ME 2010-2013). Weather and weekly orchard scouting data were used in developing an organic disease and arthropod management program following standard protocols (Cooley et al., 2014, Berkett et al., 2007, Braun and Craig, 2008).

Tree survival and growth

Annual tree survival was assessed at the end of each season and total percent survival calculated at the end of the study in 2013. Trunk diameter for each tree was measured at the end of each season using a caliper (Absolute Digimatic CD-8"CS,

Mitutoyo U.S.A., Aurora, IL) with two measurements recorded for each tree along a north- south and east-west alignment. Trunk cross sectional area (TCSA) was then calculated from mean tree diameter measurements. Tree height and width were measured at the end of the 2012 growing season. Measurements were collected in meters by an observer who viewed the tree against a survey rod (Crain Enterprises, Inc. Mound City, IL) held by a second person; two width measurements (east-west and north-south) were collected and averaged to determine mean tree width. Vegetative terminal shoot length was assessed at the end of each growing season. The length of five terminals for each tree was measured to the nearest centimeter with a standard ruler. Measurement was taken by resting the bottom of the ruler against the base of the current year’s terminal growth and taking the reading at the terminal end of the current year’s growth. Length of any remaining leaves at the terminal end of the current year’s growth was not included.

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Crop yield

Crop yield data were evaluated for 2008-2013, the beginning of which was when trees began to produce fruit on the scion cultivar. A small crop of fruit was produced in

Orchard 2 in 2007 on nurse limbs retained in that season from the original cultivar,

‘McIntosh’ or ‘Liberty’, which is not included in this analysis. All trees of each cultivar within each orchard were harvested on the same day in each year. Fruit flavor, color, and preharvest fruit drop conditions were used to determine harvest timing. Individual fruit weight was measured with a digital scale (Mettler PM600, Mettler Instrument Corp.

Highstown, NJ) from a sample of ten fruit per tree in Orchard 1 or twenty five fruit per tree in Orchard 2. Fruit that had dropped to the orchard floor prior to harvest were counted and the total for each tree weighed on a field scale field scale (SV-100, Acculab U.S.A,

Bohemia, NY) before disposal. Percent of the fruit which had prematurely dropped to the orchard floor was calculated from harvested and dropped fruit and averaged for each cultivar in each orchard for 2008-2013. Dropped fruit were not assessed in 2012 due to wild geese eating the fruit prior to assessment, and total fruit production (harvested plus dropped fruit) was not evaluated because of this missing data for that year. All fruit on each tree were counted and the total harvested crop per tree weighed in the field. Dead trees were included as missing data in this measurement so that crop performance of live trees could be evaluated without dead trees reducing mean yield. Total crop yield was accumulated for all years. Cumulative yield efficiency was calculated as total accumulated kg fruit per tree / TCSA at the end of the study. Harvested kg fruit per tree were converted to Mg/ha based on tree spacing and accumulated from 2008 - 2013 for comparison with results from other published studies. In that calculation, trees that had died during the

64 experiment were given a yield of zero in order to include tree survival in the assessment.

This assumed that the proportion of trees that died during the study would be consistent when expanding the data to represent a full hectare.

Statistical analysis

For each dataset, measured parameters were assessed by year, orchard, cultivar, and replicate. Where appropriate, grand means for each cultivar were evaluated across all years

2008-2013. Proportional data were transformed using arcsine square root prior to statistical analysis, but reported cultivar means represent values from non-transformed data. Data from each orchard were analyzed separately, because the experimental design does not lend to direct comparisons between them. In both orchards, cultivar means were compared using an analysis of variance (PROC GLM) with significance level of 0.05 (SAS Version 9.3;

SAS Institute, Cary, NC). If the overall F-test was significant, pairwise comparisons were performed using Tukey’s honestly significant difference (HSD) test

RESULTS AND DISCUSSION

Tree survival and growth

Tree growth and survival data are presented in Table 2.1. Tree survival was high in

Orchard 1, where only a single ‘Macoun’ tree had died from mechanical injury associated with orchard cultivation. In contrast, significant tree mortality occurred in Orchard 2 which varied by cultivar. Given how the trees are stressed during top-grafting, some degree of tree mortality was expected. ‘Ginger Gold’ ‘Honeycrisp’, and ‘Liberty’ had greater than

86% tree survival by the end of the study, and did not differ statistically from one another.

However, approximately one-third of ‘Macoun’ and ‘Zestar!’ trees had died by the end of

2013. ‘Zestar!’ trees tended to die within the first or second year after grafting, and it was

65 suggested that precocious blooming on one-year wood may have stressed the trees during their initial establishment year (Garcia et al., 2008). ‘Macoun’ trees tended to die from different causes and from 2008 and afterward (Garcia et al., 2013). Dead trees typically developed trunk cankers and/or shelf fungi associated with unidentified wood-rotting fungi and declined over a one to three year period. These symptoms appeared similar to trunk rot issues identified on ‘Macoun’ associated with glyphosate use in another publication (Rosenberger et al., 2013).

TCSA is a commonly used measurement to estimate relative size of apple trees for comparison purposes (Westwood and Roberts, 1970). In Orchard 1, ‘Honeycrisp’ had a greater TCSA at the end of the project than all other cultivars. Because that cultivar has inherently low vigor when grafted onto fully dwarfing rootstocks (Rosenberger et al.,

2001), M.26 rootstock was used, but all other cultivars were grafted onto fully dwarfing

B.9 rootstock. Therefore, the differences observed may be attributed to increased growth from the rootstock and not the scion cultivar. Although no studies including the same cultivars and rootstocks grown under organic management in the northeastern U.S. exist, a study of twelve rootstocks and four cultivars in twelve states which included B.9 and M.26 under conventional, non-organic management may provide insights to relative tree growth performance in this orchard (Autio et al., 2001). In that study, mean TCSA among all four cultivars for B.9 and M.26 trees, respectively, were 56 cm2 and 118 cm2, which represents a difference of 85% - 89% in mean TCSA among all cultivars in Orchard 1 on those same rootstocks. Again, the results are not directly comparable because of different scion cultivars, planting sites, and non-organic management, but the magnitude of the difference suggests that the trees in this Orchard 1 were producing suboptimal growth. In Orchard 2,

66 no differences in TCSA were found among the cultivars on the top-grafted trees. Since the data presented were collected at the end of the study, trees that had died in Orchard 2 were not included. Therefore, the impact of weak or declining trees on TCSA may not have been captured by this measurement.

For mean terminal shoot growth during the fruit-bearing years of 2008-2013, in both orchards, ‘Ginger Gold’ and ‘Macoun’ had greater shoot length than all other cultivars. In Orchard 1, ‘Zestar!’ had greater shoot length than ‘Liberty’; in Orchard 2, there was no difference between ‘Zestar!’, ‘Liberty’, and ‘Honeycrisp’. Shoot length in

Orchard 1 ranged from 21.7 cm for ‘Ginger Gold” to 14.3 cm for ‘Liberty’, which is about one-half or less of the desired growth for this training system (Robinson, 2003). Terminal shoot growth in Orchard 2 ranged from 27.8 to 37.6 cm, and was appropriate for the free- standing central leader training system used.

Differences in tree height and canopy width were observed among the cultivars in each orchard. The vertical axis planting system in Orchard 1 was established at a tree spacing of 1.5 m x 4.6 m. With in-row spacing of 1.5 m and trellis height of 2.4 m, and an allowance for growth above the trellis of 0.3 m (for a total height of 2.7 m), trees with those dimensions would represent appropriate growth to fill the canopy space and maximize orchard productivity. ‘Ginger Gold’ and ‘Zestar!’ trees were taller than ‘Honeycrisp’ and

‘Liberty’ in Orchard 1. The mean of no cultivar reached the ideal tree height, but the mean height of ‘Ginger Gold’ trees was at the top of the trellis wire, so that cultivar more closely filled allocated vertical space in the trellis system. ‘Honeycrisp’ and ‘Liberty’ means only reached 80% and 66% of ideal tree height, respectively, and thus did not develop sufficient canopy to fill their allotted vertical space in the orchard. Tree width was greater for ‘Ginger

67

Gold’ in Orchard 1 than all other cultivars, and all but ‘Liberty’ had achieved 1.5 m total width. In Orchard 2, where trees were at a spacing of 3.0 m x 4.6 m and had been trained to a free-standing central leader system, ‘Ginger Gold’ and ‘Macoun’ trees were taller than

‘Honeycrisp’ and ‘Liberty’ trees, and all reached a height of at least 3.8 m which was appropriate for the production system. ‘Ginger Gold’, ‘Honeycrisp’, and ‘Liberty’ trees developed wider canopies than ‘Macoun’ and ‘Zestar!’, but all cultivars attained canopy width greater than 3 m.

Several factors may explain the poor tree growth in Orchard 1, and it is likely that they were additive. Rootstock choice may not have been appropriate for the light, sandy soil at the research site, as was suggested in a previous publication from this project

(Bradshaw, 2011). Orchard management during establishment may have been suboptimal, because weed pressure and irrigation scheduling were not optimized in the first year of the study. Also, weed management with mechanical cultivation in later years may have negatively impacted tree roots. Tree nutrition may also have affected tree growth in

Orchard 1. As a component of standard orchard management, foliar mineral assessment was completed annually in both orchards, and in all years, one or more nutrients were observed at levels below optimum, despite annual additions of soil- and foliar-applied fertilizers. However, deficiencies of the same mineral nutrients were also observed in

Orchard 2, in which tree growth was acceptable for the training system.

From 2007-2013, 10-13 sulfur or lime sulfur applications were made to each orchard annually to manage diseases. These materials are standard fungicides used in organic apple production in the northeastern U.S. (Peck and Merwin, 2009). Reduced net photosynthesis resulting from use of sulfur and lime sulfur materials for disease

68 management on apple trees has been well documented (Hyre, 1939, Palmer et al., 2003,

McAfee and Rom, 2006, McArtney et al., 2006) and may have been a factor in suboptimal tree growth in Orchard 1. In Orchard 2, increased vigor associated with grafting to an 18- year-old tree with well-established semi-dwarf M.26 rootstock may have compensated for potential negative effects on tree growth from use of sulfur and lime sulfur.

Crop yield

There were significant differences among the cultivars in harvested kg fruit per year in each orchard, (Table 2.2). Yield in Orchard 1 was low in 2008 as was expected for a newly established planting and ‘Liberty’ had the greatest yield of 0.8 kg/tree. In Orchard

2, ‘Ginger Gold’ produced 14.3 kg/tree in 2008, which was greater than all other cultivars, and had the greatest or among the greatest crop yield in all years of the study in that orchard.

‘Honeycrisp’ appeared to exhibit biennial bearing tendencies in Orchard 1, where it was among the highest-yielding cultivars in 2009, 2011, and 2013, and among the lowest in the other years. However, no trees in Orchard 1 were hand-thinned to regulate crop load in

2009 or 2010 as part of a separate study (Bradshaw et al., 2013), which likely led to increased biennialism in that orchard. Compared to the other cultivars, ‘Macoun’ was not among the highest yielding cultivars in both orchard systems except in 2012 in Orchard

1. The yield ‘Zestar!’ trees was inconsistent across the study years: in Orchard 1, it was among the highest-yielding cultivars in three of the years, and among the lowest in the remaining three growing seasons. In Orchard 2, ‘Zestar!’ yield was among the lowest in

2008 and 2012, and intermediate in yield in the other four years.

Within both orchards, there were significant differences among the cultivars in cumulative yield (kg harvested fruit /tree) from 2008-2013 (Table 2.3). In Orchard 1,

69

‘Honeycrisp’ had greater cumulative kg fruit per tree than ‘Liberty’, ‘Macoun’, and

‘Zestar!’, but did not differ from ‘Ginger Gold’; and ‘Zestar!” had lower cumulative yield than ‘Ginger Gold’ and ‘Honeycrisp’. In Orchard 2, ‘Ginger Gold’ had greater cumulative crop yield than all other cultivars, and ‘Macoun’ had lower cumulative yield than ‘Ginger

Gold and ‘Honeycrisp’ but did not differ from the other two cultivars. In order to compare to other published studies, yield in Mg/ha was calculated based on tree density in each orchard (Table 2.3). Statistical mean separation was not conducted because it is presented in the original yield (kg/tree) data. Because original yield data were collected on all living trees, with dead trees assigned as missing data, means presented do not account for tree survival.

One might expect the average annual production estimate of 15.5 MG/ha (330 bushels/acre) for Vermont orchards as reported in the New England Agricultural Statistic surveys for 2009-2013 (NASS, 2014) would be more than what was obtained in Orchard 1 since the state-wide average represents yields for all bearing orchards in the state, including fully mature orchards of dwarf and semi-dwarf trees grown primarily in non-organic apple production systems. In Orchard 2, the yields of all cultivars in 2013 exceeded the 2009-

2012 state average, and all cultivars, except ‘Liberty’ exceeded the state average of 23.9

MG/ha (507 bushels/acre) for 2013 (NASS, 2014).

No comparable studies exist in the literature which include the cultivar and rootstock combinations used in this research and grown under organic conditions.

Published studies of organic apple production of various cultivars and in the U.S. (i.e.,

Washington, New York) and Sweden reported annual yields of approximately 35 Mg/ha

(Peck et al., 2006, Peck et al., 2010) and 20 Mg/ha (Tahir and Nybom, 2013), but tree age,

70 growing conditions, cultivar, and rootstock were different from this study. In a seven-year study of rootstocks and training systems with four cultivars under non-organic management in New York, trees with the vertical axis training system at similar tree density to Orchard

1 (1283 trees/ha) on M.9 dwarfing rootstock, which produces a tree similar in size to B.9, produced approximately 30 Mg/ha in Year 4, and were considered to be nearly in full production by that time (Robinson, 2004a). Extension recommendations for orchard planning by the author of that study suggest that full production in this orchard system may be achieved by Year 7, with expected annual yields of 47 Mg/ha (Robinson, 2005). This reported expected yield for the vertical axis system is more than double the five-year average reported in production statistics for Vermont (NASS, 2014), however the Vermont average includes yields from relatively new orchards that may not be in in full production as well as older, lower-yielding orchards that comprise the majority of orchards in the state

(VTFGA, 2011). Expected yield in Robinson’s recommendations assume optimum orchard management, cultivar, and rootstock selection for the site, and thus represent ideal yields for the system. The total six-year accumulated yield in Orchard 1 for all cultivars was approximately one half to one third of annual yields from a single growing season as suggested by Robinson for the vertical axis training system.

Low yield in Orchard 1 can be attributed to three potential factors. First, in both

2010 and 2012, frost conditions occurred during or soon after bloom, which reduced fruit set and crop yield in those years. Those years were followed by large crops in 2011 and

2013, but even in those years with heavy crops no cultivar approached the yields observed in the previously mentioned studies. Second, the extensive use of sulfur and lime sulfur fungicides in both orchards likely reduced net tree photosynthesis, which has been shown

71 to reduce fruit set and size in sulfur-treated orchards (Hyre, 1939, Noordijk and Schupp,

2003, Stopar, 2004, McAfee and Rom, 2006, McArtney et al., 2006, Rosenberger and

Jentsch, 2006, Reganold et al., 2001). Third, in Orchard 1, low tree vigor and incomplete canopy development may have reduced per tree yield because potential fruit bearing area was poorly developed.

No prior research on long-term yield performance of top-grafted trees in either organic or non-organic was found in a literature search. However, in Orchard 2, the yields of all cultivars in 2013 exceeded the 2009-2012 state average, and all cultivars, except

‘Liberty’ exceeded the state average of 23.9 MG/ha (507 bushels/acre) for the 2013 growing season (NASS, 2014).” This suggests that even at lower tree densities than vertical axis and other high-density systems, precocious production with favorable yields compared to other orchard in Vermont is attainable with top-grafted trees in a central leader planting system.

Yield efficiency (YE) is a measurement that adjusts comparisons of crop yield for tree size by dividing yield by tree TCSA (Westwood, 1993). Cumulative YE (CYE) is calculated by summing yield across all years of a study and dividing by TCSA in the final year, which was done for six the years (2008-2013) of this study where a crop was produced on the scion cultivar. In Orchard 1, ‘Liberty’ had greater CYE (2.32) than ‘Macoun’ (1.95) and ‘Honeycrisp’ (which ranked the lowest among all cultivars at 1.92), and ‘Ginger Gold’

(2.29) had greater CYE than ‘Honeycrisp’. CYE for ‘Zestar!’ (1.97) was not statistically different from any other cultivar. Lower CYE for ‘Honeycrisp’ however, may not truly reflect lower productivity compared to other cultivars, since it alone was grafted on more vigorous M.26 rootstock compared to B.9 for all other cultivars, with greater TCSA than

72 all other cultivars and resulting lower CYE. However, the greater TCSA for ‘Honeycrisp’ did not reflect larger tree size, since it was among the lowest cultivars for tree height and width, as discussed above. Although direct comparisons are difficult because the cultivars and rootstocks in this study have not previously been evaluated in comparison to one another in published research, a review of eleven non-organically managed dwarfing rootstocks similar in size to B.9 with ‘McIntosh’ and ‘Fuji’ scion cultivars, and also including M.26, was conducted across 15 states and included data from the experiment station where the research in this paper was conducted (Autio et al., 2011). In the Autio et. al. study, CYE for dwarf rootstocks ranged from 2.4-3.5 for ‘Fuji’ and 2.8-4.0 for

‘McIntosh’, and all rootstocks except one had greater CYE than was observed in Orchard

1. CYE data in Orchard 1 were accumulated over six years compared to eight in the Autio et. al. study, so it is possible that two more years of production in Orchard 1 may have provided comparable CYE. However, TCSA for all cultivars in Orchard 1 at the end of the project ranged from 7.5-12.8, compared to 28-63 for all rootstocks in the Vermont planting in Autio et. al.’s study. Because YE is a function of crop yield and TCSA, improved tree growth in Orchard 1, if YE values were maintained at or near the same observed values, would have improved overall crop yield in that orchard.

CYE ranged from 0.50 for ‘Macoun’ to 0.97 for ‘Ginger Gold’ in Orchard 2, and

‘Ginger Gold’ had greater CYE than all other cultivars. The use of CYE in Orchard 2, while appropriate for comparing the cultivars within the top-grafted orchard in this study, is not useful for comparisons to other studies, because TCSA measurements were taken below the 2006 grafts, and thus represent trees that were already 18 years old at the beginning of the experiment. Few published studies exist on evaluation of apple cultivars

73 on top-grafted trees (Blazek et al., 2002, Peck et al., 2006), and none were found in a review of the literature that included CYE as a parameter.

Mean fruit weight from 2008-2013 did not differ significantly by cultivar in

Orchard 1, but ‘Liberty’ had the lowest numerical ranking and ‘Honeycrisp’ the greatest.

Mean fruit weight for ‘Liberty’ and ‘Macoun’ was under 140 g, which was the critical value required for US#1-grade fruit to be placed in the more valuable ‘Count’ category. In

Orchard 2, ‘Honeycrisp’ had greater fruit weight than ‘Liberty’ and ‘Macoun’. As referenced above, the use of sulfur and lime sulfur spray materials have been extensively shown to reduce fruit size, however ‘Liberty’, which is genetically resistant to apple scab and therefore would not require extensive use of those materials if it was the only cultivar in the orchard or was among other scab-resistant cultivars, may not have received a fair evaluation in this study. When grown in a low-input or other organic production system that does not include extensive sulfur or lime sulfur applications, ‘Liberty’ is reported as one of the more suitable cultivars for organic production. (Peck et al., 2010, Rosenberger et al., 1996, Ellis et al., 1998, Berkett et al., 2000, Peck and Merwin, 2009).

The mean percentage of fruit that prematurely dropped to the orchard floor prior to harvest did not differ by cultivar in either orchard, but overall, fruit drop incidence was often high, with the six year mean ranging from 11.8% - 30.1% in Orchard 1 and 13.2% -

32.5% of total fruit production in Orchard 2. This may represent a significant, potential economic impact on the performance of these cultivars in the two orchard systems. General lack of tree vigor in Orchard 1 and/or potentially depressed photosynthesis from sulfur applications in both orchards, plus, high populations of phytophagous mites in the

74 orchards (discussed in Chapter 3) may have exacerbated preharvest fruit drop in these orchards (Robinson, 2011)

This research was conducted to assess the horticultural performance of five apple cultivars in two types of orchard-establishment systems and managed organically in

Vermont, U.S. Results presented include a summary of collected data annually over six years from 2008-2013. In both orchards, ‘Ginger Gold’ had the greatest, or was among the cultivars with the greatest, in measurements of tree vigor and was among the highest- yielding cultivars in all years in Orchard 1, and in three of six years in Orchard 2. ‘Macoun’ had among the lowest crop yield in most years in both orchards. ‘Ginger Gold’ and

‘Honeycrisp’ had among the highest cumulative yield per tree in Orchard 1 and ‘Ginger

Gold’ in Orchard 2 had the highest cumulative yield per tree of all cultivars. ‘‘Honeycrisp’,

‘Ginger Gold’, and ‘Zestar!’ had the highest mean fruit weight in Orchard 2, but in Orchard

1, although the numerical ranking was the same, no significant differences were detected any of the cultivars. ‘Liberty’ trees ranked among the lowest of the cultivars for shoot length and tree height in both orchards, and among the lowest for fruit weight in Orchard

2. Cumulative crop yield for ‘Macoun’ was among the lowest in both orchards, and in

Orchard 2, it had lower tree survival than all cultivars except ‘Zestar!”. Like ‘Macoun’,

‘Zestar!’ had lower tree survival in Orchard 2, and was among the lowest of the cultivars in cumulative crop yield in both orchards. Results from this study in conjunction with information from assessments of disease and arthropod pest incidence and economic performance of these cultivars within the two systems will provide information to assist in the selection of cultivars and/or orchard systems for future organic production in the northeastern U.S.

75

ACKNOWLEDGEMENTS

The research was part of the OrganicA Project which was funded with major grants from the USDA Integrated Organic Program (IOP) and the Organic Research and Extension

Initiative (OREI) program, and with support from the Universities of Vermont, Maine, and Arkansas.

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TABLES AND FIGURES Table 2.1 Tree survival and growth measurements

Mean vegetative Percent tree TCSA (cm2) terminal Tree height Tree canopy survivalz 2013y lengthx (m)w width (m)w Orchard 1 Ginger Gold 100.0 9.1 bv 21.7 a 2.43 a 1.78 a Honeycrisp 100.0 12.8 a 16.7 bc 2.17 b 1.58 b Liberty 100.0 7.5 b 14.3 c 1.80 b 1.44 b Macoun 97.8 9.0 b 19.7 a 2.32 ab 1.56 b Zestar! 100.0 9.0 b 18.3 b 2.35 a 1.52 b cultivar (p)u 0.5363 <0.0001 <0.0001 <0.0001 <0.0001

Orchard 2 Ginger Gold 94.7 a 163.2 36.2 a 4.23 a 3.73 a Honeycrisp 94.7 a 164.9 27.8 b 3.85 b 3.88 a Liberty 86.8 a 157.9 31.2 b 3.79 b 3.59 a Macoun 65.8 b 155.5 37.6 a 4.36 a 3.19 b Zestar! 63.2 b 165.6 29.1 b 4.17 ab 3.17 b cultivar (p) <0.0001 0.0539 <0.0001 0.0001 <0.0001 zData were collected at end of 2013 growing season. Values represent mean percent tree survival of original trees (n=80 per cultivar in Orchard 1, n=38 per cultivar in Orchard 2. yData were collected at end of 2013 growing season. Values represent mean trunk cross- sectional area of all living trees for each cultivar. xValues represent mean of annual measurements from 2008-2013 for vegetative shoot length per cultivar within each orchard.. wData were collected at the end of the 2012 growing season. Values represent mean tree height and width for all living trees per cultivar within each orchard. vValues followed by the same letter within a row do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for mean separation by cultivar. u P-value for overall F-test to detect differences among culivars in each orchard.

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Table 2.2 Annual harvested kg of fruit per tree, 2008-2013

2008z 2009 2010 2011 2012 2013 Orchard 1 Ginger Gold 0.0 cy 2.0 b 1.3 ab 5.9 a 1.4 bc 9.4 ab Honeycrisp 0.0 c 5.6 a 0.6 b 6.9 a 1.8 bc 12.7 a Liberty 0.8 a 3.9 ab 0.5 b 3.4 b 1.3 c 7.5 b Macoun 0.3 b 2.6 b 1.0 ab 3.7 b 4.0 a 6.9 b Zestar! 0.1 bc 1.9 b 1.6 a 3.0 b 2.5 ab 10.8 a cultivar (p) <0.0001 <0.0001 0.0066 <0.0001 <0.0001 0.0005

Orchard 2 Ginger Gold 14.3 a 18.1 a 16.3 a 35.0 a 13.6 ab 58.6 a Honeycrisp 2.3 b 13.9 ab 8.2 c 24.2 bc 21.9 a 36.7 bc Liberty 3.9 b 18.9 a 10.6 bc 13.1 c 25.3 a 27.1 c Macoun 0.7 b 3.2 c 3.5 d 17.2 c 7.4 b 40.9 b Zestar! 1.5 b 9.3 b 14.1 b 27.4 b 7.5 b 40.6 b cultivar (p)x <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 zValues represent annual harvested crop yield from 2008-2013 for all living trees. Live trees with no fruit were assigned a yield of 0; dead trees were recorded as missing values. yValues followed by the same letter within a column do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for mean separation by cultivar. x P-value for overall F-test to detect differences among culivars in each orchard.

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Table 2.3 Cumulative yield, yield efficiency, fruit weight, and preharvest fruit drop.

Cumulative Cumulative Cumulative net crop yield net crop yield net yield Mean fruit Mean percent kg/treez Mg/hay efficiencyx weight (g)w fruit dropv Orchard 1 Ginger Gold 21.6 abu 31.0 2.29 ab 162.1 12.5 Honeycrisp 24.7 a 35.5 1.92 c 168.9 13.9 Liberty 17.8 bc 25.6 2.32 a 121.5 20.1 Macoun 17.7 bc 25.4 1.95 bc 135.2 30.1 Zestar! 16.6 c 23.8 1.97 abc 161.9 11.8 cultivar (p)t <0.0001 0.0015 0.2005 0.2182

Orchard 2 Ginger Gold 155.9 a 111.9 0.97 a 198.7 ab 13.2 Honeycrisp 107.2 b 76.9 0.66 b 225.6 a 21.7 Liberty 100.2 bc 71.9 0.63 b 161.3 b 32.5 Macoun 73.6 c 52.8 0.50 b 156.5 b 31.6 Zestar! 101.1 bc 72.5 0.62 b 185.0 ab 26.6 cultivar (p) <0.0001 <0.0001 0.0006 0.1818 zValues represent harvested crop yield per tree accumulated from 2008-2013 for all living trees. Live trees with no fruit were assigned a yield of 0; dead trees were recorded as missing values. yValues represent cumulative yield per hectare calculated from kg harvested fruit per tree and tree density in each orchard. Data are presented for comparison purposes with other studies, no statistics were performed. xCumulative yield efficiency = cumulative kg fruit per tree (2008-2013)/TCSA in 2013. wValues represent grand mean of annual (2008-2013) percentage of fruit that prematurely dropped to the orchard floor and was not harvested (kg dropped / kg harvested + dropped). Live trees with no fruit were assigned a yield of 0; dead trees were recorded as missing values. Fruit drop data were not collected in 2012. vValues represent grand mean of annual (2008-2013) means of individual fruit weight. Fruit weights were collected on a sample of 10 fruit per tree in Orchard 1 or 25 fruit per tree in Orchard 2, if available. uValues followed by the same letter within a column do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for mean separation by cultivar. tP-value for overall F-test to detect differences among culivars in each orchard.

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CHAPTER 3: JOURNAL ARTICLE- DISEASE AND ARTHROPOD PEST INCIDENCE IN TWO ORGANIC APPLE ORCHARD SYSTEMS IN VERMONT, USA, 2008-2013

Terence L. Bradshaw1, Lorraine P. Berkett1, Heather M. Darby1, Robert L. Parsons1, Renae E. Moran2, M. Elena Garcia3, Sarah L. Kingsley-Richards1, Morgan C. Griffith1, Sidney C. Bosworth1, and Josef H. Gorres1 1University of Vermont, 2University of Maine, 3University of Arkansas

Keywords: Malus ×domestica, ‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’, ‘Macoun’, ‘Zestar!’, integrated pest management, apple scab, rust, fruit rots, mites, Lepidoptera pests

ABSTRACT

In regional environments conducive to apple disease development and with populations of numerous arthropod pests, effective disease and arthropod management is a significant challenge commonly cited as the primary impediment to increased adoption of organic apple production. The results presented summarize six years of seasonal data of disease symptoms and arthropod infestations and/or damage on foliage and fruit on five organically-managed apple cultivars (‘Ginger Gold’,

‘Honeycrisp’, ‘Liberty’, ‘Macoun’, and ‘Zestar!’) grown in a newly planted orchard

(Orchard 1) and a top-grafted established orchard (Orchard 2). Significant differences were found among cultivars for all assessed diseases except powdery mildew which was rarely observed in the study. ‘Ginger Gold’ and/or ‘Macoun’ had significantly greater foliar and fruit scab than ‘Honeycrisp’ and ‘Liberty’ in both orchard systems. The low incidence of scab on ‘Honeycrisp’ foliage and fruit and

‘Zestar!’ fruit was not statistically different than the scab-resistant cultivar ‘Liberty’

83 on which no scab was observed. Apple rusts were present on foliage, with ‘Ginger

Gold’ and ‘Honeycrisp’ having the highest incidence and ‘ Zestar!’ having the lowest in both orchards. ‘Macoun’ and ‘Liberty’ ranked the highest in the percentage of fruit without arthropod damage in both orchard systems but differences among the other cultivars were not distinct. Management of lepidopteran pests of fruit was a major challenge on all cultivars over the years of the study. European red mite incidence was high in both orchards, but only in Orchard 2 were there differences among cultivars, where ‘Ginger Gold’ and ‘Honeycrisp’ had greater incidence than

‘Macoun’ and ‘Zestar!’, with ‘Liberty’ not different from any other cultivar. These results combined with analyses of tree growth, crop yield, and economic performance comparing the five cultivars within each orchard system will aid growers in their decision-making to select cultivar(s) and orchard establishment methods for an organic production system.

INTRODUCTION

Disease and arthropod pest management is commonly cited as the primary impediment to increased adoption of organic apple production systems in the eastern

United States (U.S.) (Earles, 1999, Peck and Merwin, 2009). Over eighty disease and arthropod pests of apples are potentially present in the northeastern U.S. (Agnello et al.,

2006), and each of them may negatively impact performance of both organic and non- organic orchard systems if not properly managed. Research was initiated in Vermont to evaluate arthropod and disease incidence and damage on fruit and foliage of five commercially-important apple cultivars grown under organic management in two orchard production systems: a newly planted orchard and a top-grafted established orchard. Results

84 presented are a six-year summary of arthropod pest and disease incidence (2008-2013); results from specific years have already been published (Berkett et al., 2008, Berkett et al.,

2009b, Berkett et al., 2013). These results plus analyses of horticultural and economic performance comparing the five cultivars within each orchard system, which will reported in separate articles (Bradshaw et al., 2015b, Bradshaw et al., 2015c), will provide apple growers with comprehensive information on cultivar performance under organic management in two representative orchard systems and will aid in their decision-making as to which cultivar(s) would fit best into their organic production system.

MATERIALS AND METHODS

Experimental design and orchard management

In 2006, two apple orchards were established at the University of Vermont

Horticulture Research and Education Center in South Burlington, VT (lat. 44.43162, long.

-73.20186, USDA hardiness zone 5a, Köppen-Geiger classification Dfb) as part of the

Organic Apple Research and Demonstration (OrganicA) Project (Berkett et al., 2009a,

Berkett et al., 2006). The orchard soil is a Windsor Adams loamy sand, characterized by its coarse, sandy texture, extremely good internal water drainage, low organic matter, and generally low nutrient availability and cation exchange capacity.

Orchard 1 was planted in April 2006 with the cultivars ‘Ginger Gold’, ‘Liberty’,

‘Macoun’, and ‘Zestar!’ on Bud. 9 rootstock and ‘Honeycrisp’ on M.26. rootstock at a tree spacing of 1.5 m x 4.6 m and trained to a vertical axis system. Each cultivar was replicated

15 times with three-tree replications in a completely randomized design. A previous orchard was removed from the site in 2003 and site preparation included lime application and cover cropping for two years following commercial recommendations (Peck and

85

Merwin, 2009, Pruyne et al., 1994, Robinson, 2005). Orchard 2 was an existing orchard planted in 1988 with ‘McIntosh’ and ‘Liberty’ trees on M.26 rootstock which was top- grafted in April 2006 to the same five cultivars as were planted in Orchard 1. New cultivars were grafted in a randomized complete block design with two-tree replications. There were eight replications with ‘Liberty’ interstock and eleven with ‘McIntosh’ to block any effect of the original cultivar on new scion growth. Block effects from the original scion cultivar on pest incidence were only observed for the proportion of fruit without insect damage in

2010 and 2012 (p=0.03 & 0.05) during the study, and are not considered significant to the overall research focus. Thus, all data were pooled between the blocks for this study for a total of 19 replications per cultivar in Orchard 2.

The following standard organic orchard management practices were conducted during each growing season: groundcover management via mowing, mulching, and mechanical and hand tillage (Orchard 1) and mowing (Orchard 2); tree training and pruning; use of drip irrigation; and application of mineral nutrient materials according to standard organic commercial recommendations (Peck and Merwin, 2009, Cooley et al.,

2014). Orchard sanitation practices including removal of fruit that dropped onto the orchard floor prior to harvest, leaf shredding in autumn or early spring, removal of diseased and dead wood, and pruning to an open canopy were performed annually. Hourly on-site weather data including temperature, humidity, precipitation, wind speed and direction, solar radiation, and leaf wetness were recorded continuously during the study period using an automated weather station (Davis Vantage Pro Plus, Model # 6162, Davis Instruments

Corp., Hayward, CA from 2006-2009; Rainwise MK-II, Rainwise, Inc., Trenton, ME

2010-2013).

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Weather and weekly orchard scouting data were used in developing an organic pest management program following standard protocols (Cooley et al., 2014, Berkett et al.,

2007, Braun and Craig, 2008). Organically-approved spray materials were applied annually to assist in arthropod pest and disease management. Mineral-based disease management sprays included a single application of copper hydroxide (Champ WG,

Nufarm Americas Inc., Burr Ridge, IL) and 10-13 applications of sulfur (Microthiol,

United Phosphorous, Inc., King of Prussia, PA) and/or liquid lime sulfur (Miller Lime

Sulfur, Miller Chemical & Fertilizer Corp., Hanover, PA) annually in both orchards. In addition, a Bacillus subtilis-based material (Serenade MAX, AgraQuest, Inc., Davis, CA) and/or streptomycin (Agrimycin 17, Nufarm Americas, Inc.), were used when necesary

(2010, 2012) to manage fire blight (Erwinia amylovera (Burrill) Winslow et al.). Arthropod management spray materials applied annually included: one to three applications of horticultural oil (JMS Stylet Oil, JMS Flower Farms, Inc., Vero Beach, FL); one to three applications of extract of neem oil (Trilogy, Certis USA, LLC, Columbia, MD) or the neem-derived material azadiractin (Aza-Direct, Gowan Co., Yuma, AZ); five to nine applications of kaolin clay (Surround WP, Tessenderlo Kerley, Inc., Phoenix, AZ); one to four applications of spinosad (Entrust, Dow Agrosciences, Indianapolis, IN); and three to twelve applications of Bacillus thuringiensis (Dipel DF, Valent USA Corp., Walnut Creek,

CA). Mating disruption for codling moth and oriental fruit moth was deployed in 2013

(Isomate TT CM/OFM, Pacific Biocontrol Corp., Vancouver, WA). In addition, pyrethrum

(Pyganic 1.4, McLaughlin Gormley King Co., Minneapolis, MN) was applied once each in 2008 and 2013; codling moth granulosis virus (CYD-X, Certis USA LLC) applied nine, eight, and three times in 2011, 2012, and 2013, respectively; and two applications of a

87 formulated Chromobacterium subtsugae material (Grandevo, Marrone Bio Innovations,

Davis, CA) were applied in 2013 to both orchards.

Disease and arthropod assessment on foliage

In late July or August of each year, assessments of disease (incidence and severity) and arthropods (damage or presence) on foliage were conducted on all cultivars in both orchards with the exception that assessments were not conducted in Orchard 2 in 2013. In

Orchard 1, two vegetative terminal shoots on five randomly selected three-tree replicates

(six terminals per replicate) were assessed each year. In Orchard 2, sample size was increased as the tree canopies grew; in 2008, four vegetative terminal shoots per tree were assessed in eight two-tree replications; in 2009, five shoots per tree were assessed in six replications; and for 2010-2012, ten shoots were assessed per tree on six replications.

Observers used 10x magnification to aid in foliage assessmentand commonly-used field guides to assist with disease and arthropod identification (Agnello et al., 2006, Jones and

Aldwinckle, 1990). Assessed variables included the following foliar diseases and foliar- feeding arthropod pests: apple scab (Venturia inaequalis (Cooke) Wint.)); rusts including cedar, hawthorne, and Japanese apple rusts (Gymnosporangium spp.); necrotic leaf spot

(caused by Botryosphaeria obtusa (Schwein.) Shoemaker, Alternaria mali (Simmons), or

Gymnosporangium spp.); powdery mildew (Podosphaera leucotricha (Ellis & Everh.)

Salmon); spotted tentiform leafminer (Phyllonorycter blancardella (Fabr.)); European red mite (Panonychus ulmi (Koch)); two-spotted spider mite (Tetranychus urticae (Koch)); white apple leafhopper (Typhlocyba pomaria (McAtee)); potato leafhopper (Empoasca fabae (Harris)), and Japanese beetle (Popillia japonica (Newman)). Also, beneficial

88 predator arthropods including black hunter thrips (Leptothrips mali (Fitch)); gall midge

(Diptera: Cecidomyiidae); green lacewing (Neuroptera: Chrysopidae); hover fly (Diptera:

Syrphidae); ladybeetle (Coleoptera: Coccinellidae); and predacious mites (Typhlodromus pyri (Scheuten)) were assessed. Fire blight incidence was sporadic during this study, and is not reported in these results. For each assessed shoot, the total number of leaves and leaves with presence or absence of evaluated diseases and arthropods were recorded and percent incidence was calculated from recorded data. For apple scab, rust, necrotic leaf spot, powdery mildew, and spotted tentiform leafminer, the number of lesions or mines on affected leaves was also recorded to assess severity. Because predator arthropod incidence was low for each, a predator index was calculated by summing all leaves with any predator

(except T. pyri, which was assessed separately) present and dividing that by the number of leaves on the terminal.

Disease and arthropod assessment on fruit

In each year, a sample of 10 fruit per tree in Orchard 1 and 25 fruit per tree in

Orchard 2 was collected from all cultivars at the normal harvest date for each cultivar and held in regular air storage at 2°C for up to one week prior to assessment. Difference in sample size between the two orchards reflected differences in canopy size between the two orchards. If the full 10 or 25 fruit per tree were not available, the total number of harvested fruit from the tree was assessed. All replicates (15 in Orchard 1, 19 in Orchard 2) were assessed in each year. The same observer graded all fruit for the duration of the project to minimize variation between observations. Damage from the following diseases and arthropods were assessed: apple scab; rusts including cedar, hawthorn, and Japanese apple rusts; quince rust (Gymnosporangium clavipes (Cooke & Peck); fruit rots (Botryosphaeria

89 spp. and Colletotrichum spp.); lenticel spotting, characterized by a darkening around fruit lenticels which may indicate early symptoms of black rot (Botryosphaeria obtusa

(Schwein.) Shoemaker); sooty blotch (caused by the complex: Peltaster fructicola

(Johnson, Sutton, Hodges), Geastrumia polystigmatus (Batista & Farr), Leptodontium elatus ((G. Mangenot) De Hoog,) and Gloeodes pomigena ((Schwein) Colby)); flyspeck

(Zygophiala jamaicensis (E. Mason)); Brooks spot (Mycosphaerella pomi (Pass.) Lindau)); plum curculio (Conotrachelus nenuphar (Herbst) Walker); tarnished plant bug (Lygus lineolaris (Palisot de Beauvois)); apple maggot (Rhagoletis pomonella (Walsh)); internal- feeding Lepidoptera including codling moth (Cydia pomonella (L.)), lesser appleworm

(Grapholita prunivora (Walsh)), and oriental fruit moth (Grapholita molesta (Busck)); surface-feeding Lepidoptera including obliquebanded leafroller (Choristoneura rosaceana

(Harris)) and redbanded leafroller (Argyrotaenia velutinana); European apple sawfly

(Hoplocampa testudinea (Klug)); rosy apple aphid (Dysaphis plantaginea (Pass.)), and; stink bugs (Pentatomidae spp.). Fruit damage was recorded and incidence (percent of fruit with damage symptoms) calculated per tree and averaged among the trees for each replicate. Standard pest identification resources were used to aid in pest damage identification during assessment (Agnello et al., 2006, Jones and Aldwinckle, 1990).

Statistical analysis

The two orchard systems were not replicated in this study; all statistical analysis of cultivar performance were conducted separately for each system and are independent of each other. For each dataset, mean incidence of disease, arthropod pest or predator incidence or severity was calculated by year, orchard, cultivar, and replicate. Grand means computed from annual means for all years (2008-2013) were evaluated by cultivar against

90 the null hypothesis that each cultivar would have the same incidence of disease and arthropod pest incidence and damage on fruit and foliage. Percent incidence data were converted to proportions and transformed using arcsine square root prior to statistical analysis, but reported cultivar means represent values from non-transformed data. In both orchards, cultivar means were compared using an analysis of variance (PROC GLM) with significance level of 0.05 (SAS Version 9.3; SAS Institute, Cary, NC). If the overall F-test was significant, indicating that pest incidence was different between two or more cultivars, pairwise comparisons were performed using Tukey’s HSD test.

RESULTS AND DISCUSSION

Foliar diseases and arthropods

Foliar disease incidence and severity are presented in Table 3.1. Apple scab incidence was greatest on ‘Ginger Gold’ in both Orchards 1 (12.8%) and 2 (15.6%) as well as on ‘Macoun’ in Orchard 2, with 12.1% of leaves affected. In both orchards, the incidence of foliar scab on ‘Honeycrisp’ was not statistically different than the scab- resistant cultivar ‘Liberty’ on which no scab was observed. ‘Ginger Gold’ and

‘Honeycrisp’ had greater incidence and severity of rust on foliage in both orchards, and

‘Zestar!’ the least incidence, although it was not statistically different from ‘Liberty’ in

Orchard 2. Given the season-long spray program including sulfur and/or lime sulfur used, particularly from tight cluster through petal fall when risk of infection is highest (Jones and

Aldwinckle, 1990), and that mean foliar incidence ranged from approximately 10% to over

30% across the cultivars in each orchard, it appears these materials are not effective in managing foliar rust symptoms on susceptible cultivars although the experimental design did not include a non-treated control for comparison. This was supported in a study in New

91

York in which a sulfur-based fungicide program had no effect on rust compared to a non- organic treatment which used conventional synthetic fungicides (Rosenberger and Jentsch,

2006). Necrotic leaf spot incidence (NLS) ranged from 8.1% - 30.4% of leaves affected in

Orchard 1, and 4.9% - 27.3% in Orchard 2. Incidence was greatest on ‘Macoun’ in both orchards, although incidence was not statistically different from ‘Zestar!’ in Orchard 1.

‘Honeycrisp’ had lowest incidence of NLS in both orchards. Powdery mildew incidence was less than 0.1% in both orchards in the study, with no separation between cultivars and no incidence reported at all in Orchard 2.

Arthropod incidence and damage on foliage are presented in Table 3.2. No differences among cultivars was seen in either orchard for spotted tentiform leafminers, with less than one percent of leaves affected on all cultivars. There were no differences among cultivars in incidence of white apple leafhopper (WALH) damage in Orchard 1, but in Orchard 2, ‘Zestar!” had greater damage than ‘Honeycrisp’, ‘Liberty’, and ‘Macoun’; and ‘Ginger Gold’ had greater incidence than ‘Macoun’. However, effects on fruit size, quality, or tree health are not likely at the incidence levels observed in this study based on research in Washington State (Beers et al., 1995) where impacts on fruit size and quality were not observed at high infestation levels of 6.5 nymphs per leaf. Although WALH nymphs were not enumerated in Orchards 1 or 2, field observations during assessments indicate that levels were well below one nymph per leaf on all cultivars in both orchards.

Potato leafhopper (PLH) damage was greater on ‘Macoun’ than ‘Ginger Gold’ or ‘Liberty’ in Orchard 1, and ‘Zestar!’ did not differ from any other cultivar, with overall incidence ranging from 0.4% - 1.9% of foliage with damage. ‘Honeycrisp’ was not assessed for PLH damage in either orchard because it closely resembles physiological leaf yellowing inherent

92 to that cultivar, making identification difficult (Rosenberger et al., 2001). In Orchard 2,

‘Liberty’ and ‘Macoun’ had greater PLH damage incidence than ‘Ginger Gold’, and

‘Zestar!’ again did not differ from any other cultivar. Foliar damage incidence from PLH ranged from 2.1% - 10.0% of evaluated leaves in that orchard. No thresholds exist and the impact from PLH damage on apple tree productivity is not quantified in the scientific literature, so it is unknown if the level of damage as averaged over time in the six-year means, especially in Orchard 2, would negatively impact cultivar performance. Damage from Japanese beetle to foliage was greatest on ‘Honeycrisp’ in both Orchards 1 and 2, with incidence of 5.8% and 6.6%, respectively. It is also unknown whether this level of damage may have impacted tree growth, crop yield, and fruit quality in this study.

Sequential sampling guidelines for August in New England orchards correlate 85% of leaves with mites present to economic damage thresholds of 7.5 mites per leaf and recommend treatment at that level (Cooley et al., 2014). Incidence of European red mite

(ERM) ranged from 93.5% - 97.1% of leaves affected in Orchard 1 and from 87.0% -

95.0% in Orchard 2. Only in Orchard 2 were there differences among cultivars, and ‘Ginger

Gold’ and ‘Honeycrisp’ had greater incidence than ‘Macoun’ and ‘Zestar!’, with ‘Liberty’ not different from any other cultivar. ERM density (mites per leaf) was not assessed in this study, but observations of greater than 20 mites per leaf were common during assessments over the six years and above the economic damage threshold. In contrast, the grand means for two-spotted spider mites (TSSM) incidence for all cultivars ranged from 15.2% - 22.0% in Orchard 1 and 5.4% - 16.7 % in Orchard 2. ‘Liberty’ had greater incidence of TSSM than ‘Macoun’ in both orchards, and ‘Honeycrisp’ also had greater TSSM incidence than

‘Macoun’ in Orchard 2. No differences were observed among cultivars in both orchards

93 for predacious T. pyri mites, which were present on less than one percent of leaves. There were also no differences in general predator index among cultivars in either orchard. materials used in this orchard, including kaolin, sulfur, lime sulfur, and pyrethrum have been shown to have suppressive effects on both predatory (T. pyri) and phytophagous mite populations (including ERM and TSSM), but reductions of predator mites disrupts biological control of ERM and TSSM and has been shown to increase populations of phytophagous mites in orchards (Holdsworth, 1972, Beers et al., 2009, Benedict, 2005,

Cooley et al., 2014, Marko et al., 2008, Beresford et al., 1996). High levels of ERM on all cultivars in both orchards may have contributed to reduced tree vigor, crop yield, fruit weight, and increased preharvest fruit drop because these pests feed on leaf tissue fluids including chlorophyll and photosynthates, thus reducing tree productivity (Lienk, 1980,

Lakso et al., 1996, Francesconi et al., 1996, Mobley and Marini, 1990).

Disease and arthropod damage on fruit

Differences were detected among some of the cultivars in both orchards when the combined disease incidence on fruit was calculated and analyzed (Table 3.3). In Orchard

1, ‘Ginger Gold’ and ‘Honeycrisp’ had a lower percentage of fruit (78.2% and 79.3%, respectively) without disease symptoms than ‘Macoun’ or ‘Zestar!’ (87.7% and 86.8%) which had the highest percentage. In Orchard 2, ‘Macoun’ had the highest percentage of fruit without disease symptoms (88.6%), followed by ‘Liberty’, with (82.6%).

‘Honeycrisp’, had the lowest percentage (65.8%) of fruit without disease symptoms, but was not statistically different from ‘Ginger Gold’ (75.3%). For specific diseases, ‘Ginger

Gold’ and ‘Macoun’ had a greater incidence of apple scab on fruit than ‘Honeycrisp’ and

‘Liberty’ in both orchards. The incidence of scab on ‘Honeycrisp’ and ‘Zestar!’ fruit was

94 not statistically different than the scab-resistant cultivar ‘Liberty’ on which no scab was observed. The six-year mean of scab incidence in Orchard 1 was close to or within the one percent damage range acceptable for non-organic apple producers in the region (Agnello et al., 2005). In Orchard 2, ‘Macoun’ and ‘Ginger Gold’ had a six-year mean of 4 - 5% of fruit with scab, which may affect commercial fruit grade and reduce profitability. Incidence of lesions from rust diseases also varied among the cultivars. It should be noted that quince rust symptoms were included in assessments of rust in 2008-2011; in 2012 and 2013, quince rust, which has a distinctively different lesion than the other rusts, was specifically assessed and data were recorded separately from other rust symptoms. The percentage of fruit with rust lesions ranged from 0.8% - 16.1% in Orchard 1 and 0.5% - 10.6% in Orchard

2. ‘Ginger Gold’ had the greatest incidence of rust on fruit in both orchards, followed by

‘Liberty’ (which was not statistically different from ‘Honeycrisp’ in Orchard 1). ‘Macoun’ had the lowest incidence of rust on fruit in both orchards. As discussed previously, it appears that a sulfur/lime sulfur-based fungicide program as used in these orchards was relatively ineffective in managing rust on susceptible cultivars in this study. However, no non-treated control was included, so complete assessments of those materials’ effectiveness against rusts cannot be made, which suggests an area for future research.

Quince rust, as noted previously, was assessed separately in 2012 and 2013. ‘Zestar!’ had the greatest percentage of fruit with quince rust symptoms in both orchards, with 1.2% and

1.1% in Orchards 1 and 2, respectively. This suggests that the contribution of quince rust to the total rust incidence on the other cultivars from 2008-2011 was likely low. It cannot be determined if the disease was relatively well-managed with the spray programs used or the orchards were not at high risk for infection because the cultivars are naturally resistant

95 to the disease and/or inoculum levels were very low. In a study conducted in New York, sulfur-based fungicide programs contributed to management of the disease compared to a non-treated control (Rosenberger and Jentsch, 2006).

Fruit rots, including potentially black rot, white rot, and/or bitter rot, were a significant problem in both orchards. ‘Honeycrisp’ had the highest incidence of fruit rot in both orchards, with 9.0% and 18.2% of fruit affected in Orchards 1 and 2, respectively, but in Orchard 1 it did not differ statistically from ‘Zestar!’ which had 5.3% of fruit with rot.

‘Macoun’ had the lowest incidence of rot in both orchards, but it was not statistically different from ‘Liberty’ in Orchard 1. Lenticel spots observed on fruit post-harvest were assessed separately from fruit rots, but likely were early infections from Botryosphaeria rot-inducing species (Rosenberger and Jentsch, 2006). Lenticel spotting ranged from 0.1%

- 2.9% in Orchard 1 and 1.4% - 6.6% in Orchard 2, and was greater on ‘Honeycrisp’ and

‘Zestar!’ than ‘Macoun’ in Orchard 1. In Orchard 2, ‘Honeycrisp’ showed greater lenticel spotting than ‘Ginger Gold’ and ‘Liberty’. The levels of fruit rots were important in this study, because during fruit grading for economic evaluation, any fruit with rots are automatically placed into the ‘Cull’ grade, which has no economic value, but symptoms of other diseases, depending on severity, may not necessarily reduce fruit grade (USDA,

2002). The use of sulfur-based fungicides after fruit set to manage apple scab may have contributed to increased susceptibility to fruit rots by damaging fruit lenticels, thereby creating an entry wound for rotting pathogens, as has been reported in other studies (Palmer et al., 2003, Trapman, 2002, Rosenberger and Jentsch, 2006). ‘Honeycrisp’ in particular suffered significantly from fruit rots, which may be an impediment to adopting that cultivar for organic production in the northeastern U.S.

96

The ‘summer diseases’ of sooty blotch and flyspeck are considered cosmetic but can cause fruit to receive a lower commercial grade if severe. Sooty blotch was generally more common than flyspeck, and the later harvested cultivars ‘Liberty’ and ‘Macoun’ had the greatest sooty blotch incidence in both orchards, but incidence on ‘Liberty’ was not different from ‘Honeycrisp’ and ‘Ginger Gold’ in Orchard 2.. Although data were not collected on the severity of sooty blotch on the fruit, sooty blotch symptoms rarely affected the commercial grade of fruit in this study (T. Bradshaw, pers. obs.). Brooks spot disease assessment began in 2009. In Orchard 1, ‘Macoun’ had greater incidence of Brooks spot than ‘Ginger Gold’, and the remaining cultivars did not differ statistically from each other.

In Orchard 2, Brooks spot incidence separated into three rankings, with ‘Honeycrisp’ having greatest incidence, followed by ‘Liberty’ and ‘Zestar!’, then by ‘Ginger Gold’ and

‘Macoun’. Typically considered a minor disease (Anderson, 1956), the incidence in this study (up to 15.4% of fruit affected across six years) suggests that Brooks spot may be of greater concern in organic orchards in this region.

The average percent of fruit without insect damage over the six year period of the study ranged from 54.9% - 68.4% in Orchard 1 and 56.5% - 70.9% in Orchard 2 (Table

3.4). ‘Macoun’ had the highest percentage of fruit without insect damage in both orchards, but was not significantly different from ‘Liberty’ in either orchard. Differences among the other cultivars were not distinct. Plum curculio damage did not differ among the cultivars in Orchard 1, with incidence ranging from 5.4% to 9.3%. ‘Honeycrisp’, ‘Liberty’, and

‘Zestar!’ had greater incidence of plum curculio damage on fruit than ‘Macoun’ in Orchard

2. Damage were of two types; the most common was the characteristic crescent-shaped scars which, if under 6 mm in diameter, may not by itself reduce commercial fruit grade

97

(USDA, 2002). Another type of damage observed was internal corking which severely disfigured fruit. This damage appeared to be similar to boron deficiency (Stiles and Reid,

1991), but it always occurred in conjunction with typical plum curculio feeding damage, and the damage was suggested by a regional fruit entomologist as common for PC injury

(H. Reissig. pers. comm.). Damage of this type would likely reduce commercial fruit grade.

Kaolin clay particle film was applied in all years from bloom through mid-June to manage plum curculio, and overall incidence of fruit damage was comparable to previous work by the authors which assessed the efficacy of Kaolin application over four years (T. Bradshaw, unpublished data). This indicates that the observed level of PC damage in this study may be expected in organically-managed orchards in the region.

Fruit damage from tarnished plant bug (TPB) was greater on ‘Ginger Gold’ than

‘Macoun’ in Orchard 1, and in Orchard 2, ‘Ginger Gold’ had greater damage from TPB than ‘Honeycrisp’, ‘Liberty’, and ‘Macoun’. Damage ranged from 5.8% - 11.1% of fruit affected across all orchards and cultivars. Damage from tarnished plant bug is considered primarily cosmetic, and small stings may not necessarily downgrade fruit (USDA, 2002).

This pest is most active prebloom, when insect management sprays are typically reduced to minimize issues with pollinators (Cooley et al., 2014). The six-year averages of fruit with apple maggot damage ranged from 0% - 0.5% , with no differences detected among cultivars in either orchard, and this level is considered commercially tolerable for non- organically managed orchards in the region (Agnello et al., 2005).

Lepidopteran pest damage was observed on all cultivars in both orchards. Damage was categorized as ‘internal’ or ‘surface’ depending on the depth and nature of feeding damage. Fruit damage from internally-feeding Lepidoptera was assumed to be primarily

98 from codling moth, and every larvae from affected fruit inspected during the study were identified as such. However, lesser apple worm and oriental fruit moth were observed in pheromone trap captures during the study, so some damage may be attributed to them.

‘Honeycrisp’ had greatest incidence of damage from internally-feeding Lepidoptera in both

Orchard 1 (17.4%) and Orchard 2 (16.8%), although in Orchard 1 it was not statistically significant from ‘Liberty’ or ‘Zestar!’. Initial management of codling moth and other summer Lepidoptera consisted of particle films applied for plum curculio management plus

Bacillus thuringiensis and spinosad applied based on trap captures and degree day models.

When especially high damage levels were observed in 2010 (Berkett et al., 2013), codling moth granulosis virus was included in the spray program, and in 2013, mating disruption was deployed farm-wide. Because damage is in the form of open wounds and live larvae can remain in the fruit, damaged fruit would be downgraded using USDA grading standards to ‘Cull’ category which has no economic value. In addition, feeding wounds from internal Lepidoptera could also become infected by fruit-rotting fungi which may serve as inoculum that could affect adjacent fruit.

A second category of Lepidoptera feeding, where damage occurred on or just below the skin surface, was observed and likely caused by oblique- and red- banded leafrollers and possibly codling moth larvae although the causative species were not determined.

Damage from surface-feeding Lepidoptera differed among cultivars in both orchards.

‘Ginger Gold’ and ‘Zestar!’ had the greatest incidence in both orchards with more than

20% damage over the six years, although neither differed statistically from ‘Honeycrisp’.

Surface-feeding Lepidopteran damage may not be as important when evaluating the economic value of the fruit as internal Lepidopteran damage, because slightly damaged

99 fruit may be graded into the ‘Utility’ category (which have a reduced value versus no value for ‘Cull’ fruit), but damaged fruit would not be included in the higher-valued US#1 grades. Frequent applications of Bacillus thuringiensis and spinosad appeared to be insufficient overall in managing surface-feeding Lepidopteran damage, although both materials are considered to have good efficacy against surface Lepidoptera (Cooley et al.,

2014).

European apple sawfly (EAS) damage incidence ranged from 0%-0.3% in Orchard

1 and was not different among cultivars, but in Orchard 2, cultivar differences were found, with ‘Liberty’ having greater damage (0.7%) than all cultivars except ‘Ginger Gold’

(0.4%), and ‘Macoun’ having the least damage (0.1%) but not statistically different from

‘Honeycrisp’ (0.2%) or ‘Zestar!’ (0.3%). Because EAS damage on fruit at harvest is characterized by a dry, corked scar that does not compromise the integrity of the skin, it may not affect fruit grade depending on the size of the scar. However, EAS injury at the fruit set period may cause some severely affected fruit to drop to the ground, so the effects of EAS activity on cultivar performance may be greater in that it may have reduced crop yield, and that effect may not have been captured in this study. Stink bug damage differed overall among cultivars in Orchard 1 (p=0.0495), although after applying Tukeys’ adjustment for multiple comparisons, no mean separation among cultivars was observed.

In Orchard 2, ‘Ginger Gold’ had greater incidence of stink bug damage on fruit than all other cultivars, ‘Honeycrisp’ had less damage than ‘Macoun’, and the remaining cultivars were not statistically different from one another. Rosy apple aphid damage was below 1% on all cultivars in Orchard 1 with ‘Ginger Gold’ having the greatest incidence (but not statistically different than ‘Honeycrisp’), with the remaining cultivars having no damage

100 from this insect. ‘Honeycrisp’ however had significantly greater fruit damaged than all other cultivars from rosy apple aphid in Orchard 2 with 1.5% of fruit affected. All rosy apple aphid damage was observed in 2009, so that pest appears to have been sporadic and not significant in the long-term study.

The objective of the research was to evaluate cultivar differences in incidence and/or severity of disease and arthropod pest and damage on fruit and foliage within two orchard systems managed organically. This paper provides an overall assessment using the six-year averages of the many disease and arthropod variables affecting cultivar performance Among the five cultivars evaluated in both systems, no cultivar or orchard system was without challenges from pests and disease. Rust and rot diseases were difficult to manage given the organic management programs used. Arthropods that were most challenging to manage included Lepidopteran species, plum curculio, tarnished plant bug, and phytophagous mites. Results from this study in conjunction with the results of assessments of the horticultural and economic performance of these cultivars within the two systems will provide information to assist in the selection of cultivars and/or orchard systems for future organic production in Vermont and the region.

ACKNOWLEDGEMENTS

The research was part of the OrganicA Project which was funded with major grants from the USDA Integrated Organic Program (IOP) and the Organic Research and Extension

Initiative (OREI) program, and with support from the Universities of Vermont, Maine, and Arkansas.

101

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Agnello A., Nyrop, J., Reissig, H. and Straub, D. 2005. Reduced-risk pest management in apples using pheromone disruption and a selective pesticide program. Report to the USDA Risk Avoidance and Mitigation Project (RAMP). Available at: http://web.entomology.cornell.edu/agnello/assets/RAMP_2005_NY_Full_Report.pdf.

Anderson H.W. 1956. Diseases of Fruit Crops. McGraw-Hill Biik Company, Inc., New York. 501 pp.

Beers E., Elsner, E. and Drake, S. 1995. White apple leafhopper (Homoptera: Cicadellidae) effect on fruit size, quality, and return bloom of apple. J. of Econ. Entomol. 88:973-978.

Beers E., Martinez-Rocha, L., Talley, R. and Dunley, J. 2009. Lethal, sublethal, and behavioral effects of sulfur-containing products in bioassays of three species of orchard mites. J. of Econ. Entomol. 102:324-335.

Benedict C. 2005. Non-target Impact of Kaolin on Phytophagous (acari: Tetranychidae) and Predatory Mites (acari: Phytoseiidae) in an Apple Agro-ecosystem. M.S.Thesis, University of Vermont.

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Berkett L., Garcia, E., Moran, R., Parsons, R., Darby, H., Hayden, J., Bradshaw, T. and Kingsley- Richards, S. 2008. Apple cultivar disease evaluation under organic management in Vermont, 2006. Plant Disease Management Reports 2::Online publication. doi:10.1094/PDMR02.

Berkett L., Moran, R., Garcia, E., Darby, H. and Parsons, R. 2009a. Using ‘New’ Alternatives to Enhance Adoption of Organic Apple Production through Integrated Research and Extension. USDA Organic Research & Extension Initiative. 2009-51300-05530.

Berkett L., Moran, R., Garcia, E., Darby, H., Parsons, R., Bradshaw, T., Kingsley-Richards, S. and Griffith, M. 2013. Disease and arthropod evaluation of five apple cultivars under organic management in Vermont, USA. Acta Hort. 1001:235-248.

Berkett L., Moran, R., Garcia, E., Darby, H., Parsons, R. and Hayden, J. 2006. Using ‘New’ Alternatives to Enhance Adoption of Organic Apple Production through Integrated

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Berkett L.P., Garcia, M.E. and Cromwell, M.L. 2007. An Organic IPM Checklist for Vermont. Available at: http://www.uvm.edu/~fruit/?Page=treefruit/tf_ipm/OrganicIPMchecklist.html&SM=tf_su bmenu.html.

Berkett L.P., Moran, R.E., Garcia, M.E., Darby, H.M., Parsons, R.L., Bradshaw, T.L., Kingsley- Richards, S.L. and Griffith, M.C. 2009b. Foliar and fruit disease evaluation of five apple cultivars under organic management in Vermont, 2009. Plant Disease Management Reports 6:Online publication. doi:10.1094/PDMR06.

Bradshaw T., Berkett, L., Parsons, R., Darby, H., Moran, R., Garcia, E., Kingsley-Richards, S., Griffith, M., Bosworth, S. and Gorres, J. 2015b. Tree growth and crop yield of five cultivars in two organic apple orchard systems in Vermont, USA, 2006-2013. Acta Hort. submitted:

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Cooley D.R., Autio, W.R., Greene, D., Teveris, E., Los, L.M., Hamilton, G., Eaton, A.T., Berkett, L.P., Bradshaw, T.L., Faubert, H.H., Koehler, G. and Clements, J. (eds.) 2014. 2014 New England Tree Fruit Management Guide: USDA Cooperative Extension Service,Universities of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont.

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Mobley K.N. and Marini, R.P. 1990. Gas exchange characteristics of apple and peach leaves infested by European red mite and twospotted spider mite. J. Amer. Soc. Hort. Sci. 115:757-761.

Palmer J., Davies, S., Shaw, P. and Wünsche, J. 2003. Growth and fruit quality of ‘Braeburn’apple (Malus domestica) trees as influenced by fungicide programmes suitable for organic production. New Zealand J. of Crop and Horticultural Science 31:169-177.

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Rosenberger D., Schupp, J., Watkins, C., Iungerman, K., Hoying, S., Straub, D. and Cheng, L. 2001. Honeycrisp: Promising profit maker or just another problem child. New York Fruit Quarterly 9:9-13.

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Trapman M. The post infection use of lime sulphur to control apple scab. Experiences in the Netherlands 1999-2002. Proc. 10th International Conference on Cultivation Technique and Pathological Problems in Organic Fruit Growing and Viticulture. Weinsberg, Germany 4-7 Feb. p. 63-75.

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105

Table 3.1 Mean percent incidence and severity of foliar disease, 2008-2013

na

0.0755

0.0000

0.0000

0.0000

0.0000

0.0000

0.0008

0.0000

0.0000

0.0003

0.0007

# # Lesions/leaf

Powdery mildew

na

0.00

0.00

0.00

0.00

0.00

0.07

0.00

0.00

0.03

0.05

0.0652

% % Incidence

ab

a

c

c

bc

ab

a

bc

c

a

0.46

0.68

0.20

0.07

0.25

0.56

0.77

0.22

0.14

0.71

<0.0001

<0.0001

# # Lesions/leaf

b

a

c

d

bc

a

a

c

d

b

Necrotic leaf spot leaf Necrotic

4.9

8.1

19.3

27.3

11.1

14.1

24.2

30.4

12.2

19.6

<0.0001

<0.0001

% % Incidence

b

b

b

a

a

b

b

b

a

a

0.27

0.33

0.43

1.10

1.41

0.21

0.24

0.29

1.62

1.35

<0.0001

<0.0001

z

# # Lesions/leaf

Rusts

c

b b

bc

a

a

c

b

b

a

a

10.2

16.8

15.5

31.6

35.2

10.0

14.5

15.3

41.3

36.5

<0.0001

<0.0001

% % Incidence

y

b

a

b

b

a

ab

b

b

b

a

0.06

0.75

0.00

0.00

0.93

0.27

0.06

0.00

0.01

0.50

<0.0001

<0.0001

# # Lesions/leaf

y

x

b

a

c

c

a

b

b

c

c

a

Apple scab Apple

2.9

0.0

0.2

3.7

2.4

0.0

0.6

12.1

15.6

12.8

<0.0001

<0.0001

% % Incidence

w

v

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

P-value for overall F-test to detect differences among culivars in each orchard. in culivars F-test to among detect P-value for differences overall

Incidence reflects all affected leaves/total leaves assessed per replicate. Number of lesions is total number of lesions observed/all leaves assessed per leaves replicate. observed/all number of total lesions is Number of assessed per lesions leaves replicate. affected leaves/total all reflects Incidence

No No assessment was Orchard conducted 2013. 2 in in

Rusts included cedar hawthorn,apple, and/or rusts. Rusts Japanese included apple

Values represent grand means of annual means for each year 2008-2013. Values followed by the same letter within a column do a at not column differ by α=0.05. the within means Tukey's same means represent of letter for grand annual followed each year 2008-2013.Values Values

v

w

adjustment for multiple comparisons applied for by mean cultivar. separation applied comparisons adjustment for multiple

x

y

z Orchard Orchard 2 Orchard Orchard 1 106

Table 3.2 Mean percent incidence of foliar arthropods, 2008-2013

1.2

1.3

1.9

1.7

2.4

3.0

2.8

2.6

2.6

3.0

Index

0.1007

0.8574

Predator

0.3

0.2

0.7

0.2

0.3

0.7

0.4

0.9

0.8

0.5

0.3943

0.1719

TPYRI

% Incidence

ab

b

a

a

ab

ab

b

a

ab

ab

5.4

9.4

11.5

16.7

15.6

20.8

15.2

22.0

18.2

15.3

TSSM

0.0005

0.0305

% Incidence

b

b

ab

a

a

87.0

87.6

91.7

95.0

94.7

96.0

95.4

93.5

93.9

97.1

ERM

0.0035

0.1418

% Incidence

bc

c

bc

a

bc

c

c

b

a

c

1.1

0.2

2.2

6.6

1.0

0.9

0.3

3.0

5.8

0.6

JB

<0.0001

<0.0001

% Incidence

ab

a

a

b

ab

a

b

b

w

w

na

na

6.7

9.9

2.1

1.8

1.9

0.5

0.4

10.0

PLH

0.0003

0.0012

% Incidence

a

c

bc

bc

ab

3.7

1.1

1.8

1.7

3.0

0.6

0.2

0.4

0.2

0.2

predacious mites, Predator index=sum of all arthropod predators observed/number of per of assessed all Predatorleaves mites, predacious index=sum

0.2323

WALH

<0.0001

% Incidence

T. pyri

y

0.006

0.008

0.006

0.005

0.007

0.004

0.004

0.005

0.006

0.004

0.6329

0.6830

z

# Mines/leaf

y

STLM

x

0.6

0.7

0.6

0.5

0.6

0.3

0.3

0.5

0.6

0.0

0.7850

0.7383

% Incidence

v

u

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Assessment for PLHAssessment was any not year. performed in on Honeycrisp

Incidence reflects all affected leaves/total leaves assessed per replicate. Number of mines is total number of mines observed/all leaves assessed per leaves replicate. number observed/all of total mines Number is of assessed per mines leaves replicate. affected leaves/total all reflects Incidence

No assessment was Orchard conducted 2013. 2 in in

P-value for overall F-test to detect differences among culivars in each orchard. in culivars F-test to among detect P-value for differences overall

STLM=spotted tentiform leaf miner, WALH=white apple leafhoper damage, PLH=potato leafhopper damage, JB=Japanese beetle damage, ERM=motile European red mites, ERM=motile damage, PLH=potatodamage, JB=Japanese beetle damage, leafhoper leafhopper apple WALH=white miner, STLM=spottedleaf tentiform

Values represent grand means of annual means for each year 2008-2013. Values followed by the same letter within a column do a at not column differ by α=0.05. the within means Tukey's same means represent of for letter grand annual followed each year 2008-2013.Values adjustment for Values

u

v

w

multiple comparisons applied for by mean cultivar. separation applied comparisons multiple

x

y

terminal.

TSSM=motile two-spotted spider mites, TPYRI=motile mites, two-spotted spider TSSM=motile

z Orchard Orchard 2 Orchard Orchard 1 107

Table 3.3 Mean percent incidence of disease damage to fruit at harvest, 2008-2013

y

b

c

b

a

c

ab

a

ab

ab

b

2.6

8.3

3.1

6.3

8.1

5.5

6.9

0.4

0.0157

11.3

15.4

<0.0001

Brooks Brooks spot

b

a

ab

b

b

b

a

a

b

b

0.1

0.3

0.2

0.1

0.0

0.0

1.1

0.6

0.1

0.1

<0.0001

<0.0001

Flyspeck

c

a

ab

bc

bc

c

a

a

bc

bc

0.2

1.8

0.8

0.6

0.3

0.0

3.4

3.0

1.0

0.2

<0.0001

<0.0001

Sooty Sooty blotch

y

ab

ab

b

a

b

a

b

ab

a

ab

4.2

4.7

1.4

6.6

3.7

2.9

0.1

0.7

2.6

0.8

0.0020

0.0008

Lenticel spots Lenticel

b

c

b

a

b

ab

d

cd

a

bc

y

8.2

2.4

6.7

9.3

5.3

1.0

2.7

9.0

5.2

18.2

Rots

<0.0001

<0.0001

y

a

b

b

b

b

a

b

b

b

b

1.1

0.0

0.0

0.5

0.1

1.2

0.0

0.1

0.0

0.0

<0.0001

<0.0001

Quince rust Quince

c

d

b

c

a

c

d

b

bc

a

y

3.5

0.5

4.7

4.2

3.6

0.8

7.5

5.9

10.6

16.1

Rust

<0.0001

<0.0001

bc

a

c

c

a

ab

a

b

b

a

0.4

5.0

0.0

0.0

4.3

0.4

1.2

0.0

0.0

1.4

<0.0001

<0.0001

Apple scab Apple

x

z

c

a

b

d

cd

a

a

ab

b

b

77.9

88.6

82.6

65.8

75.3

86.8

87.7

83.4

79.3

78.2

<0.0001

<0.0001

No disease No disease

symptoms

w

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

P-value for overall F-test to detect differences among culivars in each orchard. in culivars F-test to among detect P-value for differences overall

Rusts included cedar hawthorn, apple, rot, rust as and/or for rusts,Rusts black quince Japanese 2008-2011.included rust apple as was 2012-2013.RotsQuince well assesed separately include

No assessment was Orchard conducted 2013. 2 in in

Incidence reflects all affected fruit/total fruit assessed per replicate. assessed per fruit replicate. affected fruit/total all reflects Incidence

Values represent grand means of annual means for each year 2008-2013. Values followed by the same letter within a column do a at not column differ by α=0.05. the within means Tukey's same means represent of for letter grand annual followed each year 2008-2013.Values adjustment for Values

u

w

multiple comparisons applied for by mean cultivar. separation applied comparisons multiple

x

bitter rot, and/orwhite rot. Lenticel spots indicate sunken areas around lenticels that may be early infectioins from black rot. Brooks spot data collection began in 2009. in began rot. from black Brooks spot data collection that may infectioins be early sunken areas around lenticels spots indicate rot,rot. bitter and/orwhite Lenticel

y

z

Orchard Orchard 2 Orchard Orchard 1 108

Table 3.4 Mean incidence of arthropod damage to fruit at harvest, 2008-2013

b

b

b

a

b

b

b

b

ab

a

0.1

0.0

0.1

1.5

0.2

0.0

0.0

0.0

0.3

0.6

aphid

0.0023

<0.0001

Rosy apple Rosy apple

bc

b

bc

c

a

0.9

1.4

0.6

0.1

2.7

2.3

0.4

0.1

0.1

0.5

0.0495

<0.0001

Stink bug Stink

bc

c

a

bc

ab

0.3

0.1

0.7

0.2

0.4

0.0

0.1

0.3

0.2

0.0

sawfly

0.1547

<0.0001

European apple European apple

y

a

b

b

ab

a

a

bc

c

ab

a

9.4

9.6

21.3

12.5

12.7

15.6

20.5

22.3

16.1

20.5

0.0002

Surface Surface

<0.0001

lepidoptera

y

bc

c

b

a

bc

ab

b

ab

a

b

7.5

6.8

7.4

6.8

7.2

11.1

16.8

10.8

10.7

17.4

0.0002

Internal Internal

<0.0001

lepidoptera

0.1

0.3

0.2

0.4

0.3

0.2

0.0

0.3

0.5

0.2

0.2651

0.3164

Apple maggot Apple

ab

b

b

b

a

ab

b

ab

ab

a

8.6

7.7

7.8

7.8

9.2

5.8

8.4

8.6

11.1

10.7

bug

0.0001

0.0048

Tarnished plant Tarnished plant

a

b

a

a

ab

9.2

4.4

9.1

6.6

9.3

6.5

8.7

5.4

7.8

10.1

0.0012

0.1040

Plum Plum curculio

x

b

a

ab

b

b

c

a

ab

bc

bc

z

60.4

70.9

64.0

56.5

59.2

54.9

75.0

68.4

59.2

60.1

<0.0001

<0.0001

damage

No insect No insect

w

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

P-value for overall F-test to detect differences among culivars in each orchard. in culivars F-test to among detect P-value for differences overall

Lepidopteran damage was not differentiated by species, but was grouped by damage type. Internal-feeding lepidoptera damage was assumed to be primarily from codling moth, from codling was assumed damage to be primarily lepidoptera by type.but species, by was was damage grouped Internal-feeding not damage differentiated Lepidopteran

Incidence reflects all affected fruit/total fruit assessed per replicate. assessed per fruit replicate. affected fruit/total all reflects Incidence

Values represent grand means of annual means for each year 2008-2013. Values followed by the same letter within a column do a at not column differ by α=0.05. the within means Tukey's same means represent of for letter grand annual followed each year 2008-2013.Values adjustment for Values

w

multiple comparisons applied for by mean cultivar. separation applied comparisons multiple

x

leafrollers. leafrollers.

with oriental fruit moth and/or lesser apple worm also potentially causing damage. Surface-feeding lepidoptera damage likely occurred from obliquebanded and/or redbanded occurred from obliquebanded likely damage lepidoptera Surface-feeding damage. causing potentially worm also moth apple and/or fruit lesser oriental with

y

z

Orchard Orchard 2 Orchard Orchard 1 109

CHAPTER 4: JOURNAL ARTICLE- LONG-TERM ECONOMIC EVALUATION OF FIVE CULTIVARS IN TWO ORGANIC APPLE ORCHARD SYSTEMS IN VERMONT, USA, 2006-2013

Terence L. Bradshaw1, Robert L. Parsons1, Lorraine P. Berkett1, Heather M. Darby1, , Renae E. Moran2, M. Elena Garcia3, Sarah L. Kingsley-Richards1, Morgan C. Griffith1, Sidney C. Bosworth1, and Josef H. Gorres1 1University of Vermont, 2University of Maine, 3University of Arkansas

Keywords: Malus ×domestica, ‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’, ‘Macoun’,

‘Zestar!’, net present value, top-graft, input costs, cultivar evaluation

ABSTRACT

Apple growers may use several systems to establish orchards intended for organic management, including the planting of new nursery trees and top-grafting existing orchards to convert to selected cultivars. Long-term economic analysis of certified organic orchard systems is critical to evaluate potential profitability of the enterprise.

The overall objective of this project was to evaluate long-term economic performance of five apple cultivars (‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’, ‘Macoun’, and

‘Zestar!’) grown in a newly planted orchard and in a top-grafted established orchard.

A summary of production costs and income for each cultivar in the two orchard systems from the year of establishment through 2013, as well as long-term financial risk by computing the net present value (NPV) of accumulated cash flow in 20 year projections, are presented. Actual management costs including labor, equipment, and inputs costs were recorded, and commercial grades for fruit and projected net income per hectare for each cultivar for each system were assessed over the study period. There were few differences among cultivars for the percentage of fruit in each

110 grade. Mean separation of fruit grade distribution within each cultivar was variable, and in Orchard 2, three of the cultivars (i.e., ‘Ginger Gold’, ‘Liberty’, and ‘Macoun’) had the highest highest percentage of fruit in the US#1 Count grade, with

‘Honeycrisp’ fruit distributed equally into US# 1 Count, Utility and Cull and with

‘Zestar!’ having no difference in % of fruit into US#1 Count and Utility grades. All cultivars in Orchard 1 had negative NPV after 20 years. In Orchard 2, ‘Ginger Gold’ attained positive NPV in Year 3, ‘Liberty’ in Year 5, and ‘Honeycrisp’ in Year 7, and

‘Macoun’ and ‘Zestar!’ in Year 8. Income calculations, which incorporate disease and arthropod impacts through fruit grade and horticultural performance through crop yield, and the long-term economic projections provide comprehensive information which apple growers can use to determine which cultivar(s) and orchard system would be best for their organic enterprise.

INTRODUCTION

Long-term evaluation of apple cultivars within different orchard systems is necessary to provide information to aid growers in selecting cultivar(s) and orchard establishment methods that will provide the best economic return under organic management. Economic assessment of conventional, non-organically-managed modern apple production systems in the northeastern United States (U.S.) has been conducted in

New York (Robinson et al., 2005, Robinson, 2006, Robinson et al., 2007), but multi-year research on organically-managed orchards in the region is lacking. In addition, no long- term study of economic performance of top-grafted orchards has been performed in the

U.S. The overall objective of this project was to comprehensively evaluate cultivar performance of five commercially-important apple cultivars (‘Ginger Gold’, ‘Honeycrisp’,

111

‘Liberty’, ‘Macoun’, and ‘Zestar!’) grown under organic management and using two orchard establishment systems: (i) a newly planted orchard with, nursery-grown trees, and

(ii) a top-grafted older, established orchard. The results presented summarizes eight years

(2006-2013) of seasonal data and long-term economic performance of each cultivar within the two orchard systems. These results plus analyses of horticultural performance and pest and disease incidence comparing the five cultivars within each orchard system, which are reported in separate articles (Bradshaw et al., 2015b, Bradshaw et al., 2015a), will provide apple growers with comprehensive information on cultivar performance under organic management in two representative orchard systems and will aid in their decision-making as to which cultivar(s) would fit best into their organic production system.

MATERIALS AND METHODS

Orchard site and experimental design

In 2006, two apple orchards were established at the University of Vermont

Horticulture Research and Education Center (HREC) in South Burlington, VT (lat.

44.43162, long. -73.20186, USDA hardiness zone 5a) as part of the Organic Apple

Research and Demonstration (OrganicA) Project (Berkett et al., 2006, Berkett et al.,

2009a). The orchard soil is a Windsor Adams loamy sand, characterized by its coarse, sandy texture, extremely good internal water drainage, low organic matter, and generally low nutrient availability and cation exchange capacity. Organic management of both orchards began in 2006, and USDA organic certification was attained in 2008.

Orchard 1 was planted in 2006 with the cultivars ‘Ginger Gold’, ‘Liberty’,

‘Macoun’, and ‘Zestar!’on Bud. 9 rootstock and ‘Honeycrisp’ on M.26. rootstock at a tree spacing of 1.5 m x 4.6 m and trained to a vertical axis system. Each cultivar was replicated

112

15 times in a completely randomized design with three-tree replications. A previous orchard was removed from the site in 2003 and site preparation included lime application and cover cropping for two years following commercial recommendations (Peck and

Merwin, 2009, Pruyne et al., 1994, Robinson, 2005). To minimize variation in original tree size and quality, all lateral shoots were removed and trees were pruned to 1 m in height at planting.

Orchard 2 was an existing orchard planted in 1988 with ‘McIntosh’ and ‘Liberty’ trees on M.26 rootstock at a tree spacing of 3 m x 4.6 m which was top-grafted in 2006 to the same five cultivars as were planted in Orchard 1. Since the original cultivar (‘McIntosh’ or ‘Liberty’) may affect growth of the new ‘top-grafted’ tree, a randomized complete block experimental designwith two-tree replications, eight replications on ‘Liberty’ interstock and eleven on ‘McIntosh’, was used to block any effect on new scion growth. Very few block effects from the original scion cultivar were observed during the study, and they will not be further discussed here; all data were pooled between the blocks for this study for a total replicate n of 19 per cultivar for Orchard 2.

Orchard management

During each growing season the following were applied according to standard organic commercial recommendations: an organically-approved disease and arthropod pest management program; weed management via mowing and mulching, mechanical and hand tillage (Orchard 1) and mowing (Orchard 2); and mineral nutrient materials application (Peck and Merwin, 2009, Cooley et al., 2014). Soil moisture tension was measured weekly (Watermark Soil Moisture Sensor, Spectrum Technologies, Inc.,

Plainfield, IL) and drip irrigation applied if below 30 cbars. Hourly on-site weather data

113 including temperature, humidity, precipitation, wind speed and direction, solar radiation, and leaf wetness were recorded continuously during the study period using an automated weather station (Davis Vantage Pro Plus, Model # 6162, Davis Instruments Corp.,

Hayward, CA from 2006-2009; Rainwise MK-II, Rainwise, Inc., Trenton, ME 2010-2013).

Weather and weekly orchard scouting data were used in developing an organic pest management program following standard protocols (Cooley et al., 2014). In both orchards, fish oil and liquid lime sulfur were applied at petal fall which aided in fruit thinning.

Beginning in 2009, remaining fruit were hand-thinned to leave a single fruit per cluster in

June, however, in order to assess effects of thinning from application of kelp-extract biostimulants, no hand thinning was performed in Orchard 1 in 2009 or 2010.

Input costs

Labor required for orchard management and harvest activities was recorded for all years. Labor tasks were divided into two groups for unskilled and skilled labor, with per hour values of US$10 and US$25 assigned, respectively. Labor was recorded for the whole orchard since management was consistent across cultivars for all years of the experiment.

The only labor activities that were variable by cultivar were hand thinning and fruit harvest, since they were dependent on fruit set and crop yield. Thinning time per tree was multiplied by the unskilled labor rate to determine cost of thinning activity per cultivar per year.

Harvest cost of US$0.06/kg was calculated from actual piece rate of US$1.20/bushel ($18.1 kg) paid to harvest laborers in commercial orchards in the region. Actual cost of orchard inputs, including trees, trellis materials, irrigation supplies, pest management materials, fertilizers, and applied pollen were recorded each year. In addition, equipment use time was recorded each year for all activities. For equipment cost calculations, the replacement

114 cost of all tools, tractors, and implements was divided by a billable hour expectancy of 500 hours to determine an hourly rate for each. Resulting costs were comparable to published estimates (Lazarus, 2014). All costs were converted to US$/ha based on tree spacing in each orchard, and data analyzed and reported on that basis.

Fruit grading

A sample of 10 fruit from each tree in Orchard 1 or 25 fruit per tree in Orchard 2 was assessed and graded annually within one week of harvest. The same observer graded all fruit for the duration of the project to minimize variation between observations. Fruit were assessed for fruit weight, percent red color, and disease and insect pest damage, described in Chapters 2 and 3. Based on fruit size, color, and incidence of defects, a grade was assigned to each fruit by the observer. Fruit grades were based on 2002 USDA grading standards that allow for combination of two adjoining grades, therefore, for this assessment, US Fancy and US#1 were combined and graded as ‘US#1’ (USDA, 2002).

General grade categories for this study included: 1) US#1 Count: fruit over >140 grams in weight, with no punctures, with minor blemishes (under 6 mm in diameter), and with red color ‘acceptable for variety’ or >50% for ‘Macoun’, ‘Liberty’, ‘Honeycrisp’, ‘Zestar!’; 2)

US#1 Bag: same standards as US#1 Count but fruit weight between 100-140 grams, grade assumes fruit would be sold in tote bags for a lower price than Count fruit; 3) Utility: may have significant cosmetic blemishes but no skin punctures unless corked over, healed ‘dry’ stings are allowed, this assumes a /processing market, where equipment considerations may be in place, so small fruit (under 100g) were rejected ; and 4) Cull: all fruit under 100 g, grossly misshapen fruit, and any fruit with open punctures or feeding wounds, rots, or other gross defects. The percentage of total fruit in each grade category

115 was calculated separately by cultivar. Data values presented are grand means of annual means of the percentage of fruit in each category 2008-2013.

Yield and income

Crop yield per tree (Chapter 2) was converted to Mg/ha based on tree spacing and accumulated from 2008 - 2013 in order to determine cumulative gross income/ha. In this calculation, trees that had died during the experiment were assigned a yield of zero in order to include tree survival in the assessment. This assumed that the proportion of trees that died during the study would be consistent when expanding the data to include a full hectare.

Gross income was calculated annually for each cultivar by multiplying harvested yield by the proportion of fruit in each grade category. The resulting kg of fruit in each category was multiplied by the following price levels: US$3.14, US$2.10, US$0.52, and

US$0.00 per kg for US#1 Count, US#1 Bag, Utility, and Cull grades, respectively. For this analysis, a retail farm stand market was assumed, which eliminated concerns over packing and storing costs and reflects the smaller-scale, retail-oriented market for most organic orchards in the region. Fruit pricing was determined through a survey of local orchards and from actual pricing in the retail farm stand at the HREC. Prices were static over the course of the study, which was justified by minimal annual variation in observed market prices.

Utility fruit price represents actual prices paid by a local processor. These prices are higher than those used in a study conducted in New York which evaluated the cultivar ‘Liberty’ grown under organic and integrated fruit production systems (Peck et al., 2010), but represent actual prices received for premium retail fruit in Vermont. Net income was calculated by subtracting annual costs from annual gross income for all cultivars in each

116 orchard. Gross and net income was accumulated from 2006-2013 by cultivar within each orchard.

Net Present Value

In order to assess long-term profitability, for each cultivar in each orchard system, net present value analyses were performed. Input, machinery, and labor costs were subtracted from orchard income for each cultivar in each year. All data were converted to

US$/ha based on tree spacing and orchard size to standardize data analysis. A discount rate was calculated based on 6% interest rate for moderate-risk investments, which is consistent with another orchard profitability study conducted in New York (Robinson et al., 2007).

Annual discount rate was calculated using the formula (1-i)t where i = interest rate and t = time in years since beginning of orchard establishment. The resulting value declines over time from 1 in year 1 (2006) to 0.309 in year 20 (2025). This net present value (NPV) calculation allows for comparison of alternative potential opportunities for investment of funds with varying lifespans compared to a given return from other investment products.

Cash flows for 2014 through 2025 were projected using an average of orchard production and expenses from 2010-2013, during which both orchards were assumed to have reached full production, which is supported by research and extension summaries for training systems from New York (Robinson, 2004a, Robinson, 2005, Robinson et al., 2007).

Annual net income or loss was multiplied by each year’s discount factor to determine annual NPV cash flow, which were then accumulated through Year 20.

Statistical analysis

All data were analyzed separately within each orchard. Cumulative yield and income data and NPV in Year 20 were subjected to analysis of variance (SAS PROC GLM)

117 by cultivar with a significance level of α=0.05. If the overall F-test was significant, pairwise comparisons were performed using Tukey’s honestly significant difference

(HSD) test. Fruit grade percentages were converted to proportions and transformed using the arcsin square root and the analyses were performed on the transformed data. Analysis of variance by cultivar, year, and cultivar x year interactions using Tukey’s HSD for multiple comparisons, was performed on fruit grade category data. Because the percentage of fruit within each category by cultivar was not independent (i.e., all combined percentages = 100); paired t-tests were performed among each category within each cultivar and orchard. Although a significance level for each t-test of α=0.05 was used, adjustments for multiple comparisons were not possible.

RESULTS AND DISCUSSION

Input costs

Actual labor, equipment, and input costs for each orchard are presented in Table

4.1. For Orchard 1, costs began to accrue in 2003 when the previous orchard was removed and site preparation work commenced. In Orchard 2, cost accrual commenced in 2006 when the trees were top-grafted. The difference in time between start dates may favor

Orchard 2 over Orchard 1, because a complete assessment of the two systems would include management costs and income for the previous crop on the non-grafted trees in

Orchard 2 for 2003-2005. However, in order to compare the new, organic cultivars in this study, costs and income from the post-grafting trees in Orchard 2 only were included in this assessment. In Orchard 1, approximately 10% of total costs from 2003-2013 were accrued during site preparation prior to planting. Costs were greatest in 2006 when the orchard was initially planted, totaling US$55,747/ha.. A high expenditure in that year,

118 listed under ‘Fertilizers’ in the table, was for pre-plant compost applied at 185 m3/ha to the tree rows based a published study that found improved tree growth and early fruit production from a similar rate of compost (Moran and Schupp, 2003). The most significant costs in that year were from orchard establishment, including tree and trellis material purchases and from labor and equipment associated with planting. Costs in Orchard 2 in

2006 were US$9,496/ha, and in fact were lower than annual management costs in some subsequent years.

Fruit grade

Fruit grade assessments are presented in Table 4.2. Overall, the combined percentage of fruit in both US#1 grades for each cultivar in each orchard system (range

35-58%) was well below the 90-95% typical of cultivars in commercial non-organic orchards (Tukey and Schotzko, 1988). The percentage of fruit within each commercial grade was only different by cultivar at α=0.05 for the US#1 Bag grade in both orchards, but in Orchard 1, no differences among cultivars was detected after applying Tukey’s adjustment for multiple comparisons. In Orchard 2, ‘Liberty’ and ‘Macoun’ had a higher percentage of fruit sorted into this grade than ‘Honeycrisp’. ‘Liberty’ and ‘Macoun’ were also the lowest ranked cultivars for fruit weight in Orchard 2 (Chapter 2), which explains the higher incidence of grading them into the US#1 Bag category, which differs from US#1 only by that parameter. For all categories, year and cultivar x year interactions were significant (P<0.0001), which indicates that grade distribution was different among cultivars each year and that cultivar distribution varied within years. This is likely explained by differences in disease, arthropod pest, and other damage incidence, and by differences in fruit weight each year that are largely explained by differences in crop load

119

(Byers, 2003). Annual differences in fruit grade distribution will be further discussed in

Chapter 5.

Distribution of fruit into commercial grades for each cultivar was important because percentages of fruit in each grade were applied to the total yield for that cultivar, and if high percentages of fruit sorted into lower-valued grades, economic performance would suffer. In Orchard 1, within ‘Ginger Gold’. ‘Macoun’, and ‘Zestar!’ the fruit were most often graded into the US#1 Count category, although the percentage of fruit in that grade was not always statistically different from other grades. Within ‘Ginger Gold’,

‘Honeycrisp’, and ‘Liberty’, the fruit were also frequently graded into the ‘Cull’ category.

The incidence of fruit rots on ‘Honeycrisp’ and ‘Ginger Gold’, discussed in Chapter 3, potentially explains the incidence of culled fruit for that cultivar. Mean fruit weight of

‘Liberty’ in Orchard 1 was 121.5 g, and given that the cultivar had among the highest percentage of fruit without disease and pest damage, fruit size might have been a primary factor in the Cull grade assigned to nearly 40% of its fruit from 2008-2013. In Orchard 2, within each cultivar, the highest-valued US#1 Count grade had the highest percentage of fruit assigned to it with two exceptions: (i) for ‘Zestar!’ where the Utility grade had 37.3%, but this was not significantly different than the percentage of fruit assigned the US#1 Count grade (31.6%); and (ii) for ‘Honeycrisp’, which had a statistically similar percent of fruit graded as Utility and Cull fruit. The percent of fruit graded as US#1 Bag was lowest for all cultivars, which reflects mean fruit weights well above the 140 g threshold as discussed in

Chapter 2.

120

Yield and income

Cumulative crop yield per hectare from 2008-2013 differed by cultivar in both orchards (Table 4.3), and mean separation by cultivar was nearly the same as for cumulative yield per tree in kg as reported in Chapter 2. Values differ slightly from the calculated yield per hectare from Chapter 2, because tree death was accounted for in this assessment by assigning a yield of zero, rather than a missing value, to dead trees. This was based on the assumption that fixed, per-acre input costs (e.g., mowing, spraying, fertilizing) would largely not change if a certain proportion of trees were no longer in the orchard, because equipment passes would continue to be made past the dead trees.. Total cumulative gross income (US$/ha) differed by cultivar in each orchard (Table 4.3). ‘Ginger

Gold’ and “Honeycrisp’ had greater cumulative gross income than ‘Liberty’ in Orchard 1, yet none differed statistically from ‘Macoun’ or ‘Zestar!’. In Orchard 2, ‘Ginger Gold’ again had the greatest cumulative gross income, followed by ‘Liberty’. Cumulative net income was calculated by subtracting fixed and variable costs accumulated since orchard establishment from accumulated gross income, and mean separation by cultivar within each orchard was the same as for net income. In Orchard 1, all cultivars had negative values which is not unexpected, because newly planted orchards systems typically do not attain positive accumulated cash flow until ten or more years after establishment (Robinson et al., 2005). However, ‘Ginger Gold’ and ‘Honeycrisp’ were less negative than ‘Liberty’.

In Orchard 2, however, all cultivars had positive net cumulative net income after the eight year from establishment, suggesting that this orchard establishment method may be preferable to planting new trees if a grower has suitable trees to graft. This finding supports previous work from the Czech Republic where top-grafted trees attained positive economic

121 return after Year 8 for some cultivar and rootstock combinations (Blazek et al., 2002).

Caution is advised in interpreting these results into commercial application, since tree death may reduce profitability of the top-grafted system. Also, the cumulative net income does not account for the time value of delayed income used in NPV analyses for both orchards which is discussed below. Among the cultivars in Orchard 2, ‘Ginger Gold’ had the highest cumulative net income, followed by ‘Liberty’ and ‘Honeycrisp’, which were not different from one another. Lower cumulative net income for ‘Macoun’ and ‘Zestar!’ could be explained by lower tree survival with those cultivars (discussed in Chapter 2).

Net Present Value

Long-term economic performance of the cultivars in each orchard assessed by NPV after 20 years is presented in Figure 4.1. In Orchard 1, all cultivars had negative NPV by year 20, and yearly NPV trend downward for all years except 2011 and 2013 for most cultivars. NPV at Year 20 ranged from -US$82,952/ha for ‘Ginger Gold’ to -

US$119,260/ha for ‘Liberty’. The magnitude of negative NPV after 20 years suggests that small changes in management, pest incidence or fruit grade would not likely bring the cultivars toward profitability. Projections after the 2013 season were based on average costs and income from 2010-2013, and projected income in particular may have been greater if yield and income were increased in later years. However, research results and extension recommendations for vertical axis-trained orchards in New York suggest that full production should be achieved by Year 7, with near-full production attained by Year

5. It is assumed that in a multi-year outlook, that from 2014-2020, an orchard may experience regular random weather events as were observed in 2006-2013, including frost events in 2010 and 2012. There is the possibility of each year in the projection having

122 favorable weather, but that is not likely to occur. Given that studies of NPV applied to orchard systems tend to use 15-20-year lifespans for evaluation (Funt et al., 1982, Bechtel et al., 1995, Blazek et al., 2002, Mouron, 2005, Robinson et al., 2007, Bravin et al., 2008), and that the cultivars in this orchard had not even approached positive NPV by Year 20 indicate that Orchard 1 was economically unsuccessful, and significant changes in initial establishment and/or management practices, including use of a more vigorous rootstock or modified training system, would be required to change the economic outlook in the future.

In contrast, all cultivars in Orchard 2 achieved positive NPV by Year 8 or earlier.

Mean separation of twenty-year projected NPV in this Orchard 2 indicated that ‘Ginger

Gold’ has the highest NPV, followed by ‘Liberty’ which was not significantly different from ‘Honeycrsip’. ‘Macoun’ and Zestar!’ had the lowest NPV among the cultivars, although ‘Honeycrisp’ was not statistically different from those cultivars. In Orchard 2,

‘Ginger Gold’ achieved positive NPV in Year 3, ‘Liberty’ in Year 5, ‘Honeycrisp’ in Year

7, and ‘Macoun’ and ‘Zestar!’ in Year 8. This is similar to a study in the Czech Republic that modelled economic performance of top-grafted trees at the same tree density which achieved positive NPV after six to ten years (Blazek et al., 2002). Higher incidence of tree death on ‘Macoun’ and ‘Zestar!’ likely had the greatest impact on NPV for those cultivars, but they also were among the lowest for harvested cumulative crop yield per tree (Chapter

2). The degree of difference between the cultivars in this orchard was significant, with NPV for ‘Ginger Gold’, US$223,313, more than double the next lower cultivar ‘Honeycrisp’ with US$108,087. In order to spread production and marketing risk and to provide a diverse product mix to customers, growers typically raise multiple apple cultivars, so it would not be realistic to suggest selecting only the most profitable cultivar in this study. In addition,

123 local growing or marketing conditions may not favor certain cultivars. For example,

‘Ginger Gold’, ripens in August, prior to the bulk of the traditional apple marketing window. Questions on storage potential and market demand for this and other cultivars further complicate the matter of cultivar choice, and suggest that NPV is only one characteristic to consider.

In Orchard 1, planting and other establishment costs of over US$55,000/ha in 2006 alone (Table 4.1) were a substantial cost which would require consistent high yield to be recouped, as is expected in high density orchards (Robinson, 2006). Groundcover management, fertilizer, and crop protection material costs were approximately double those in a study in New York of mature organic ‘Liberty’ trees, with groundcover management and spray material, labor and equipment costs notably higher in Orchard 1

(Peck et al., 2010). However, comparisons to this study of organic apple production in a similar region to Vermont are difficult to make. This is because disease management on apple scab-susceptible cultivars requires more inputs, including materials, equipment, and labor, than in an orchard composed entirely of ‘Liberty’, which is genetically resistant to the disease. In addition, the orchard used in the New York study was managed with non- organic inputs, including synthetic fertilizers and herbicides, from its establishment in 1994 through 2004. This made complete less critical for early tree establishment, since the trees had already attained full size prior to the study. In Orchard 1, complete weed control was sought using organic practices from the outset of establishment, which required significant labor and machinery expense. In contrast, Orchard 2 was initially established using non-organic practices for 18 years prior to the study, and groundcover management costs were much lower than in Orchard 1 because trees established for greater than five

124 years in the orchard are less susceptible to groundcover competition than younger trees

(Atucha et al., 2011). Mean annual groundcover management costs after the establishment year in Orchard 2, had a mowed sod groundcover versus the mulched, cultivated, or hand- weeded tree rows in Orchard 1, were 21% lower than for Orchard 1 (Table 4.1).

The intent of this research was to evaluate long-term economic performance of five important commercial apple cultivars grown organically in two orchard establishment systems in Vermont. In Orchard 1, low yield and relatively high input and labor costs contributed to negative NPV for all cultivars, and it is not expected that modest improvements in management, yield, or fruit pest incidence would improve the economic performance of the cultivars in this orchard. Crop yield and subsequent economic performance of the cultivars was likely affected by poor tree growth in Orchard 1. Factors that likely contributed to below-optimal tree growth and crop yield include: reduction in net photosynthesis attributable to repeated applications of sulfur and lime sulfur fungicides; high incidence of phytophagous mites; improper rootstock selection for the soil type and planting system; slight to moderate deficiencies of mineral nutrients, and; groundcover competition and potential root damage associated with under-tree cultivation. These factors may be addressed via scion/rootstock selection, soil management and site selection, and groundcover management in future studies. Cultivars with the highest tree survival in

Orchard 2 had the highest twenty-year NPV, and ‘Ginger Gold’ in particular performed well economically in this orchard, which suggests that top-grafting existing trees may be a successful method to transition orchards to new cultivars. Results from this study in combination with the results of assessments of horticultural performance and disease and pest incidence of these cultivars within the two systems will provide information to assist

125 in the selection of cultivars and/or orchard systems for future organic production in

Vermont and other New England states.

ACKNOWLEDGEMENTS

The research was part of the OrganicA Project which was funded with major grants from the USDA Integrated Organic Program (IOP) and the Organic Research and Extension

Initiative (OREI) program, and with support from the Universities of Vermont, Maine, and Arkansas.

LITERATURE CITED Atucha A., Merwin, I.A. and Brown, M.G. 2011. Long-term effects of four groundcover management systems in an apple orchard. HortScience 46:1176-1183.

Bechtel L., Barritt, B.H., Dilley, M.A. and Hinman, H.R. 1995. Economic analysis of apple orchard management systems with three varieties in central Washington. Research Bulletin XB1032. Washington State Univ., College of Agriculture and Home Economics Research Center Research Bulletin XB1032.

Berkett L., Moran, R., Garcia, E., Darby, H. and Parsons, R. 2009a. Using ‘New’ Alternatives to Enhance Adoption of Organic Apple Production through Integrated Research and Extension. USDA Organic Research & Extension Initiative. 2009-51300-05530.

Berkett L., Moran, R., Garcia, E., Darby, H., Parsons, R. and Hayden, J. 2006. Using ‘New’ Alternatives to Enhance Adoption of Organic Apple Production through Integrated Research, Education, and Extension. USDA Integrated Organic Program. 2006-51300- 03478.

Blazek J., Falta, V., Vavra, R. and Benes, V. 2002. Prediction of profitability of topworking in older apple orchards under contemporary economic conditions of the Czech Republic. Horticultural Science (Prague) 29:85-91.

Bradshaw T., Berkett, L., Parsons, R., Darby, H., Moran, R., Garcia, E., Kingsley-Richards, S., Griffith, M., Bosworth, S. and Gorres, J. 2015a. Disease and arthropod pest incidence in two organic apple orchard systems in Vermont, USA, 2008-2013. Acta Hort. submitted:

Bradshaw T., Berkett, L., Parsons, R., Darby, H., Moran, R., Garcia, E., Kingsley-Richards, S., Griffith, M., Bosworth, S. and Gorres, J. 2015b. Tree growth and crop yield of five cultivars in two organic apple orchard systems in Vermont, USA, 2006-2013. Acta Hort. submitted:

126

Bravin E., Mencarelli Hofmann, D., Kockerols, K. and Weibel, F. 2008. Economics evaluation of apple production systems. Acta Hort. 873:219-226.

Byers R. 2003. Flower and Fruit Thinning and Vegetative Growth: Fruiting Balance. In: Ferree, D. & Warrington, I. (eds.), Apples: Botany, Production, and Uses. CABI, Cambridge, MA.

Cooley D.R., Autio, W.R., Greene, D., Teveris, E., Los, L.M., Hamilton, G., Eaton, A.T., Berkett, L.P., Bradshaw, T.L., Faubert, H.H., Koehler, G. and Clements, J. (eds.) 2014. 2014 New England Tree Fruit Management Guide: USDA Cooperative Extension Service,Universities of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont.

Funt R., Lines, A. and Ferree, D. 1982. Rates of return of four apple production systems. Acta Hort. 135:177-184.

Lazarus W.F. 2014. Machinery cost estimates. Available at: http://faculty.apec.umn.edu/wlazarus/documents/machdata.pdf.

Moran R.E. and Schupp, J.R. 2003. Preplant monoammonium phosphate fertilizer and compost affects the growth of newly planted 'Macoun' apple trees. HortScience 38:32-35.

Mouron P. 2005. Ecological-economic life cycle management of perennial tree crop systems: The Swiss fruit farms. Ph.D. Dissertation, Swiss Federal Institute of Technology Zurich.

Peck G. and Merwin, I. (eds.) 2009. A Grower's Guide to Organic Apples: Cornell University Coop. Extension.

Peck G.M., Merwin, I.A., Brown, M.G. and Agnello, A.M. 2010. Integrated and organic fruit production systems for 'Liberty' apple in the northeast United States: A systems-based evaluation. HortScience 45:1038-1048.

Pruyne P.T., Merwin, I. and Mullin, P.G. 1994. Diagnosis of apple replant problems in New York orchard soils and evaluation of nematode-suppressive cover crops. Acta Hort. 363:121- 128.

Robinson T. 2004a. Effects of tree density and tree shape on apple orchard performance. Acta Hort. 732:405-414.

Robinson T. Replanting for success. Proc. Cornell 2005 In-Depth Fruit School. Crown Point, NY p. 147-152.

127

Robinson T. 2006. The evolution towards more competitive apple orchard systems in the USA. Acta Hort. 491-500.

Robinson T., DeMarree, A. and Hoying, S. 2007. An economic comparison of five high density apple planting systems. Acta Hort. 732:481-489.

Robinson T.L., DeMarree, A.M. and Hoying, S.A. 2005. Economic comparison of five high- density apple planting systems (abstr.). HortScience 40:1128.

Tukey R.B. and Schotzko, R.T. 1988. Evaluating orchard performance and practices from packout records. Pacific Northwest Extension Bulletin PNW322.

USDA. 2002. United States Standards for Grades of Apples. USDA Agricultural Marketing Service, Fruit and Vegetable Programs, Fresh Products Branch.

128

Tables and Figures

Table 4.1 Equipment, labor, and input costs ($US/ha).

$0

$0

$0

$93

-

-

-

236

854

452

815

2013

$700

$943

$940

$976

2013

9,564

3,468

2,189

1,551

$7,856

$2,710

$1,493

$

$

$

$

$

$

$

$

$

$

$

$0

$0

-

-

-

412

565

922

2012

$233

2012

2,199

3,155

1,906

1,932

$3,464

$2,008

$2,664

$1,147

$1,039

$1,725

$2,104

11,091

$14,384

$

$

$

$

$

$

$

$

$

$

$

$0

$0

88

-

-

-

508

744

541

2011

$140

$677

2011

4,325

2,206

2,136

$1,914

$3,824

$1,082

$1,191

$1,809

$2,344

10,547

$12,981

$

$

$

$

$

$

$

$

$

$

$

$0

$1

-

-

-

295

609

634

261

2010

$338

$649

$229

$676

2010

8,134

2,948

1,555

1,832

$2,188

$2,437

$6,336

$2,760

$15,614

$

$

$

$

$

$

$

$

$

$

$

$1

34

-

-

860

558

554

2009

$141

$709

$308

2009

9,779

1,579

2,102

2,054

2,038

$1,914

$1,392

$1,957

$2,107

$1,986

$2,174

$12,688

$

$

$

$

$

$

$

$

$

$

$

$0

$0

76

-

-

-

211

338

2008

$592

$258

2008

7,737

2,682

1,297

1,044

2,089

$1,333

$2,259

$1,670

$2,143

$2,773

$2,242

$13,270

$

$

$

$

$

$

$

$

$

$

$

Orchard 2

Orchard 1

$0

$0

81

$38

-

-

799

566

338

2007

$179

$964

$208

$206

2007

2,172

2,020

2,168

2,089

$8,032

$1,025

$3,863

$1,548

10,232

$

$

$

$

$

$

$

$

$

$

$

$38

-

-

423

914

649

703

299

347

2006

$759

$137

2006

9,496

1,564

4,598

$1,333

$2,824

$7,690

$1,664

$3,532

$55,747

$26,557

$11,212

$

$

$

$

$

$

$

$

$

$

$

$0

$0

$0

$0

$0

$502

$355

2005

-

-

-

-

-

-

-

-

-

-

$6,337

$3,114

$1,075

$1,290

$0

$0

$0

$0

$781

$314

$430

$344

2004

-

-

-

-

-

-

-

-

-

-

$4,891

$1,003

$2,018

x

$0

$0

$0

$0

$0

$0

$0

$0

2003

-

-

-

-

-

-

-

-

-

-

$2,867

$1,032

$1,835

z

y

Orchard management

Groundcover management

Fertilizers

Crop protection materials Crop protection

Orchard maintenance

Groundcover management

Orchard establishment

Orchard maintenance

Groundcover management

Orchard establishment

Orchard management

Groundcover management

Fertilizers

Crop protection materials Crop protection

Orchard maintenance

Groundcover management

Orchard establishment

Orchard maintenance

Groundcover management

Orchard establishment

x: Cost accrual began in 2003 for in Orchard began Cost commenced. 1 accrual preparation orchard and when site previous removal x:

y: Labor hours were multiplied by $25 and $10 per hour for skilled and unskilled labor, respectively. labor, by $25 and and unskilled $10 per Labor hour hours y: for were skilled multiplied

z: Equipment costs were derived from purchase price divided by useful life of equipment to determine hourly rate hourly per to of determine piece. equipment life by useful costs were from Equipment purchase derived divided z: price

Total non-variable costs Total non-variable

Inputs

Labor

Equipment

Non-variable costs Non-variable

Total non-variable costs Total non-variable

Inputs

Labor

Equipment Non-variable costs Non-variable Table 4.1 costs and labor, Equipment, ($US). input 129

Table 4.2 Commercial fruit grade distribution, 2008-2013

US#1 Count US#1 Bag Utility Cull Orchard 1 Ginger Gold 35.6 Az 15.6 B 27.8 A 21.0 A Honeycrisp 33.3 B 10.5 C 21.0 B 35.2 A Liberty 19.0 C 28.8 B 12.3 D 39.9 A Macoun 28.9 A 28.7 A 17.4 B 25.0 B Zestar! 35.0 A 12.3 C 27.9 B 24.8 B cultivar (p) 0.6053 0.0436 0.3264 0.3630

Orchard 2 Ginger Gold 41.9 A 6.9 C\ab 26.4 B 24.9 B Honeycrisp 34.1 A 1.1 B\b 29.1 A 35.6 A Liberty 38.8 A 13.4 C\a 22.2 B 25.6 B Macoun 36.3 A 15.4 C\a 22.5 B 24.7 B Zestar! 31.6 A 3.8 C\ab 37.3 A 25.9 B cultivar (p) 0.6401 0.0021 0.2162 0.6481 zValues represent grand means of annual means of percent of fruit assigned to each grade category for each year 2008-2013. Values followed by the same capital letter within a row do not differ in paired t-tests at α=0.05. No adjustments for multiple comparisons were applied to correlated data within cultivars. Values followed by the same lower-case letter within a column do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for mean separation byyP-value cultivar. for overall F-test to detect differences among culivars for each fruit grade.

130

Table 4.3 Cumulative yield, gross income, & net income, 2006-2013

Cumulative yield Cumulative gross Cumulative net (Mg/ha)z income, $US/ha income, $US/ha Orchard 1 Ginger Gold 30.7 aby $ 44,699 a $ (77,893) a Honeycrisp 35.5 a $ 42,831 a $ (80,682) a Liberty 25.6 bc $ 27,280 b $ (94,300) b Macoun 25.1 bc $ 38,433 ab $ (83,444) ab Zestar! 23.6 c $ 35,952 ab $ (85,303) ab cultivar (p)x <0.0001 0.0023 0.0037

Orchard 2 Ginger Gold 108.4 a $ 187,689 a $ 109,717 a Honeycrisp 72.7 b $ 93,445 bc $ 22,195 bc Liberty 66.2 b $ 116,816 b $ 46,374 b Macoun 38.7 c $ 66,713 c $ 90 c Zestar! 50.3 bc $ 69,154 c $ 3,603 c cultivar (p) <0.0001 <0.0001 <0.0001 zValues represent cumulative yield and net income for 2008-2013. Cumulative gross income includes input and management costs from 2003 - 2007 for Orchard 1 or 2006-207 for Orchard 2. Cumulative yield/ha, gross income, and net income were calculated from per-tree yield and fruit grading based on tree density, and dead trees were assigned yield=0 to account for tree loss. Assumed crop prices were: US#1 Count: US$3.14; US#1 Bag: US$2.10; Utility: US$0.52; and Cull: US$0.00 per kg , respectively yValues followed by the same lower-case letter within a column do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for mean separation by cultivar.x P-value for overall F-test to detect differences among culivars for each fruit grade.

131

Figure 4.1: NPV of accumulated cash flow ($US/ha) 2006-2025

Net present value for Orchard 1 (above) and Orchard 2 (below) calculated at 6% discount rate from 2008-2025 using actual recorded expenses and estimated income through 2013 and projected net income from mean of 2010-2013 through 2025.

132

CHAPTER 5: COMPREHENSIVE SUMMARY OF THE ORGANICA PROJECT AND AREAS FOR FURTHER INVESTIGATION

INTRODUCTION

In order to fully understand the opportunities and challenges of organic apple production in New England, research on cultivars and planting systems used by growers was needed to assess the commercial potential to produce important cultivars preferred by consumers under organic management. Challenges to increased commercial production of organic apples in the region include pest and disease pressure, groundcover management, tree nutrition management, tree vigor and crop yield (Earles, 1999, Moran, 2007). The majority of apples grown commercially in Vermont are traditional, non-disease resistant genotypes, including ‘McIntosh’, ‘Empire’, ‘Cortland’, and ‘Red Delicious’ (VTFGA,

2011). Those cultivars, especially ‘McIntosh’, are susceptible to apple scab, the most significant disease of the crop in the region (MacHardy, 1996). However, beginning in the

1990s, newer apple cultivars with high consumer acceptance and potentially less susceptibility to apple scab began to be planted which represented an opportunity to assess their performance under an organic management program. As new apple cultivars were planted in Vermont, growers used two different systems to establish new cultivars in their orchard by either planting a new orchard with nursery-grown trees or by top-grafting an older, established orchard. Tree density began to increase in many orchards which used the vertical axis and other trellised tree training systems with 1200 or more trees per hectare, as compared to older freestanding trees with planting densities around 500 trees per hectare (Robinson, 2006, VTFGA, 2013). Newer high density orchard systems may

133 improve overall orchard profitability through increased early fruit production, and narrow, open tree canopies may improve pest management through improved spray material penetration and sunlight interception which reduces canopy moisture, thereby potentially reducing incidence of diseases and arthropod pests. In orchards which required removal of older trees from orchard sites and extensive pre-plant site preparation, thereby taking land out of commercial production for several years, top-grafting existing orchards was another alternative that growers used to change cultivars (R. Allen, pers. comm.).

Disadvantages of top-grafting orchards include graft failure, inability to change rootstock or site conditions, and potential tree decline (Hartmann and Kester, 2002, Blazek et al.,

2002). No research had been conducted in Vermont on the performance of top-grafting trees to change cultivar. The rationale and major objective for pursuing this research as submitted to the USDA programs that funded the bulk of the project are presented in

Appendix 1.

ORCHARD ESTABLISHMENT AND EXPERIMENTAL DESIGN

The hypothesis of this research project was that the five selected commercially- important and high-valued apple cultivars ‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’,

‘Macoun’, and ‘Zestar!’ grown in Vermont would respond differently from one another for horticultural, disease and pest incidence, and economic performance parameters when managed organically in two different orchard establishment systems. The two orchards, referred to as Orchard 1 and Orchard 2 and described in detail below, were managed similarly and contained the same cultivars, but were not set up for direct statistical comparison, and results are addressed separately by orchard in this research project. The

134 experimental design in each orchard used the cultivar as the treatment, so all trees received the same organic management practices in each season..

In 2006, two apple orchards were established at the University of Vermont

Horticulture Research and Education Center in South Burlington, VT (lat. 44.43162, long.

-73.20186) as part of the Organic Apple Research and Demonstration (OrganicA) Project

(Berkett, Moran et al. 2012). Site climate Köpper-Geiger classification is Dfb (snow, fully humid, warm summer) and USDA hardiness zone 5a, with 1295 mean growing degree days

(base 10°C) (NOAA, 2002). Orchard soil is a Windsor Adams loamy sand, characterized by its coarse sandy texture, extremely good internal water drainage, low organic matter, and generally low nutrient availability and cation exchange capacity (Allen, 1973). Cultivar selection was based from consultations with apple growers in Vermont and the region. .

Growers were asked to identify high value, regionally adapted, horticulturally successful cultivars that were proven in their orchards and which they would be interested in growing organically to supply consumer demand.. Maps of both orchards are included in Appendix

2.

Orchard 1 was planted in April 2006 with the cultivars ‘Ginger Gold’, ‘Liberty’, and ‘Macoun’, and ‘Zestar!’ on Bud. 9 rootstock and ‘Honeycrisp’ on M.26. at a tree spacing of 1.5 m x 4.6 m and trained to a vertical axis system. M.26 rootstock was selected for ‘Honeycrisp’ due to an inherent lack of vigor in that cultivar (Rosenberger et al., 2001).

Each cultivar was replicated 16 times in a completely randomized design with three-tree replications. One replicate per cultivar containing a dead or weak tree was dropped from the project in 2007 or 2008 for the remainder of the study, leaving 15 three-tree replicates per cultivar that were used for data analysis. A previous orchard was removed from the site

135 in 2003 and site preparation following commercial recommendations included lime application and cover cropping for two years with sudangrass, buckwheat, rye, and rape

(Pruyne et al., 1994, Robinson, 2005, Peck and Merwin, 2009). Immediately prior to planting, 185 m3/ha compost was applied to the tree rows based on research that found improved tree growth with a similar rate of compost (Moran and Schupp, 2003). While this application was made at considerable expense, it was expected that the nutrients in the compost would be released over several years and thus would serve as a long-term fertility treatment that would reduce the need to apply expensive organic fertilizers in future years

(Travis et al., 2003). In order to minimize variation in original tree size and quality, all lateral shoots were removed and trees pruned to 1 m in height at planting. It is important to note that Orchard 1 was organically managed from the outset and thus, the critical years of early established did not involve conventional, non-organic management tools such as fertilizers, herbicides and pest management tools which potentially would have influenced growth differently.

Orchard 2 was an existing orchard planted in 1988 with ‘McIntosh’ and ‘Liberty’ trees on M.26 rootstock that was ‘top-grafted’ in April 2006 to the same five cultivars as were planted in Orchard 1. Since the original cultivar (‘McIntosh’ or ‘Liberty’) may affect growth of the new ‘top-grafted’ tree, a randomized complete block experimental design with two-tree replications, eight replications on ‘Liberty’ interstock (the remaining scion trunk section above the M.26 rootstock onto which grafts were made) and eleven on

‘McIntosh’, was used to block any effect on new scion growth. Block effects were only observed for trunk cross sectional area (TCSA) in 2011, 2012, and 2013 (p= 0.03, 0.05, &

0.01, respectively) and proportion of fruit without insect damage in 2010 and 2012 (p=0.03

136

& 0.05, respectively). Because the observed effects were relatively tangential to the primary focus of the study and represent a small portion of the total dataset collected, they were ignored for this analysis, and all data was pooled for both interstocks in the orchard.

ORCHARD MANAGEMENT

During the study, an organically-approved disease and arthropod pest management program, weed management via mulching, mechanical and hand tillage, and mineral nutrient materials were applied as needed based on standard recommendations which were organically-acceptable (Peck and Merwin, 2009, Cooley et al., 2014, Stiles and Reid,

1991). Hourly on-site weather data including temperature, humidity, precipitation, wind speed and direction, solar radiation, and leaf wetness were recorded continuously during the study period using an automated weather station (Davis Vantage Pro Plus, Model #

6162, Davis Instruments Corp., Hayward, CA from 2006-2009; Rainwise MK-II,

Rainwise, Inc., Trenton, ME 2010-2013). Soil moisture tension was measured weekly

(Watermark Soil Moisture Sensor, Spectrum Technologies, Inc., Palinfield, IL) and drip irrigation applied if below 30 cbars. Organic certification was received and the first crop of fruit was harvested in 2008.

Nutrient management

Soil and foliar nutrient applications were made annually to provide adequate levels of mineral nutrients to support tree growth and fruit production (Appendix 3). These actions were based upon nutrient recommendations for conventional orchards (Stiles and

Reid, 1991). Orchard fertilization was performed to prevent mineral deficiencies during this study, but optimum levels for many nutrients for commercial non-organic trees were difficult to attain using organically-certified materials at recommended manufacturer rates

137 and timing. Plant tissue samples were collected annually for each cultivar in both orchards following standard protocols and analyzed by the University of Maine Analytical Lab

(Orono, ME) for nitrogen, phosphorus, potassium, calcium, magnesium, boron, zinc, manganese, copper, aluminum, and iron. Total N was determined using the Dumas standard combustion (Sweeney, 1989). All other nutrients were measured by dry ashing

(Chapman and Pratt, 1961). Solution analysis was by plasma emission. Foliar tissue sample results are presented in Appendix 4.

In general, levels of mineral nutrients in foliar tissue were within recommended guidelines from the University of Maine Analytical Laboratory (summarized in Appendix

4). Foliar nitrogen levels were nearly always above recommended levels, and were deficient only in Orchard 1 in 2012 on ‘Ginger Gold’, ‘Honeycrisp’, and ‘Liberty’.

Calcium, magnesium, boron, and zinc were deficient on all cultivars in most years, and were added annually through foliar sprays or soil application. Copper was also deficient in several years, and was applied annually in pest management sprays to manage fire blight and apple scab. Given the low organic matter, coarse sand content, and low cation exchange capacity of the orchard soil, nutrient deficiencies could be expected to be common.

Observed deficiencies may have contributed to reduced cultivar performance in both orchard systems, but fertility management practices used to mitigate deficiencies likely reduced the impact of low nutrient uptake, and those practices were applied equally to all cultivars in each orchard as to not affect comparisons of the cultivars within each system.

In commercial production, growers may tailor nutrient applications to the specific needs of a particular cultivar, so specific nutrient deficiencies observed within cultivars may have been better addressed.

138

Organic pest management

Because apples are a perennial crop, the practices of crop rotation, between-crop soil building, and fallowing land are not feasible options for breaking pest cycles and improving pest management as they are used in annual cropping systems (Zehnder et al.,

2007). Most pest management programs used in commercial orchards prior to the 1970s focused on elimination of diseases and pests through application of broad spectrum pesticides, disregarded the benefits of relationships between pests and their predators, and were reductionist in nature by separating out production functions without considering interrelated functions in the orchard ecosystem such as fertilizer use and disease incidence, for example (Whalon and Croft, 1984). With the introduction of Integrated Pest

Management (IPM) into fruit production in the last quarter of the 20th century, commercial orchard production systems began to replace chemical practices with knowledge of the orchard ecosystem such that pesticide use could be reduced by identifying critical management times in a pest or disease’s life cycle, by adopting thresholds of tolerance for certain levels of pests, and by encouraging biological and cultural control in the orchard

(Prokopy et al., 1994).

Pest management practices were an important component of overall management of both orchards in this study. During each growing season the following were applied according to standard organic commercial recommendations: an organically-approved disease and arthropod pest management program; weed management via mowing mulching, mechanical and hand tillage (Orchard 1) and mowing (Orchard 2); and mineral nutrient materials (Peck and Merwin, 2009, Cooley et al., 2014).. Orchard sanitation practices including removal of fruit fruit which had prematurely dropped to the orchard

139 floor, leaf shredding in autumn or early spring, removal of diseased and dead wood, and pruning to an open canopy were performed annually. In addition, a collection of non- managed ornamental crabapples adjacent to the study orchards and an ornamental juniper collection were removed from the site in 2009 to reduce inoculum for diseases and pests.

Weather and weekly orchard scouting data were used in developing an organic pest management program following standard protocols (Cooley et al., 2014, Berkett et al.,

2007, Braun and Craig, 2008).

The resulting pest management spray applications applied to both orchards, presented in detail in Appendix 5, was similar in number to non-organic commercial orchards in the region (Cooley and Coli, 2009). Such reliance on pesticides as used in this study may suggest that the form of management represented an input substitution model instead of an agroecology-based holistic system (Rosset and Altieri, 1997). However, the underlying premise of Organic certification requires that growers develop a long-term farm plan that utilizes ecosystem functions, plant host resistance, and cultural practices to reduce pest and disease incidence prior to applying chemical pesticides (National Organic

Standards Board (NOSB), 1995). Those same principles, excepting the restriction of non- approved pesticide materials, are also at the foundation of IPM systems (Ehler, 2006), and as such, substitution of spray materials for organically-acceptable versions in the study orchards constitutes the most ecologically-focused approach for the system.

Central to the number of pesticide applications made to the orchards are two factors.

First, the use of cultivars susceptible to apple scab requires the use of protective sprays in

Vermont and the region in both organic and non-organic systems in order to produce a commercially-acceptable crop, (MacHardy, 1996). Because there are presently no

140 effective, organically-acceptable options to sulfur and lime sulfur materials for managing apple scab (Cromwell et al., 2011, Peck and Merwin, 2009), the use of those materials on the scab-susceptible cultivars in the present research planting was necessary. The use of all scab-resistant cultivars in this study would have significantly reduced the number of fungicide applications, but sprays would still have been needed to manage other diseases and, as noted previously, Vermont growers, who advised in the selection of cultivars in this project, are interested in planting cultivars that have proven consumer appeal such as

‘Ginger Gold’ and ‘Zestar!’

The second factor that contributes to regular spray applications in orchards managed for dessert fruit is the presence of arthropod pests roughly from the pink bud stage until harvest. Because apple orchards, as a perennial crop, cannot use crop rotations as in annual systems, and large tree canopies and rough bark provide habitat for overwintering pests, management of arthropods will be required in all commercial orchards, whether organic or not. In many cases, cultural management of orchard groundcovers and tree canopies may enhance natural biological control of certain pest species, but in commercial orchards, such tactics cannot be solely relied upon to provide sufficient marketable fruit

(Simon et al., 2010). Individual pests vary in the intensity required for their management as well. In the northeastern U.S., plum curculio is an annual pest for which management is assumed to be required annually, with biological monitoring only used to determine when to halt spray applications for the season (Reissig et al., 1998). In this study, five to nine applications of kaolin clay were applied annually to manage plum curculio.

Codling moth is another pest that requires frequent pesticide applications annually to manage fruit damage levels in commercial orchards. In New England, this pest is also

141 assumed to be present for all commercial producers, with early-season monitoring used to time applications to control first generation moths (Cooley et al., 2014). Although no trap capture thresholds exist for determining the need to apply pesticides for later generations, weekly captures of five or more moths per week indicate a high population that would likely require management (H. Reissing, pers. comm.). InOrchards 1 and 2, codling moth trap captures of five moths in one week occurred in all years except 2013, when pheromone mating disruption was deployed (Appendix 5). In many years, trap captures of 20 or more moths in a single week indicated that the population of this pest was particularly high, and despite frequent applications of materials to manage it, damage was significant as was described in Chapter 3. Mating disruption as was used in 2013 works by saturating the orchard area with synthetic pheromones that prevent males from finding females, but this also prevents males from finding traps, so the low trap capture numbers in 2013 are not necessarily indicative of a reduced population in that year. Recent work on developing new lures to monitor codling moths in orchards that use mating disruption suggests that, with non-pheromone-based attractants, trap captures of one moth or more per week indicate a need for spray application (Knight and Light, 2005). That threshold was attained in four weeks in 2013 in this study, even with the use of less effective pheromone attractants.

Overall, codling moth pressure was high in Orchards 1 and 2, and the pest management program used was based on population monitoring and best practices developed through applied research.

HORTICULTURAL EVALUATION

Horticultural performance of the evaluated cultivars in both orchard systems was discussed in Chapter 2. Overall tree survival was good, except for ‘Macoun’ and ‘Zestar!’

142 in Orchard 2. ‘Zestar!’ trees tended to die due to graft incompatibility or decline soon after grafting (Garcia et al., 2013). However, ‘Macoun’ trees typically declined 3-5 years after grafting, and often had trunk cankers or peeling bark at the tree base, although some dying trees of other cultivars also had the same symptoms (Figure 5.1). The presence of wood- rotting fungi in the heartwood of the trees prior to top-grafting was likely, based on darkening of the heartwood of the cut stump. Trunk cankers on declining or dying trees are common on ‘Macoun’ trees grown in the region, although other cultivars may also be affected (Rosenberger, 2007). Tree death as was observed in Orchard 2 is a recognized issue in top-grafted orchards, and is likely to have significant impacts on orchard profitability (Blazek et al., 2002).

Tree growth, however, was generally poor in Orchard 1. Tree height, canopy width, and terminal shoot length generally were below optimum based on tree spacing and trellis design, and although mean tree width reached 1.5 m for all cultivars, narrow or incomplete canopies in the tops of trees contributed to many gaps in the ‘fruiting wall’ that is sought in this training system, as illustrated in Figure 5.2. As outlined in Chapter 2, cumulative yield efficiency (the amount of crop yield per unit area of tree size) was near that for trees in a multi-year evaluation of eleven non-organically managed dwarfing rootstocks similar in size to B.9 with ‘McIntosh’ and ‘Fuji’ scion cultivars conducted across 15 states and included data from the experiment station where the research in this paper was conducted

(Autio et al., 2011). Therefore it could be surmised that an increase in tree canopy size would increase crop yield per hectare. Rootstock selection, soil management and site selection, and groundcover management would be appropriate factors to consider to improve tree growth in newly planted organic orchards in future studies

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Crop yields in Orchard 2 were acceptable for an organic or non-organic management system. Observed yields approached or exceeded the 2009-2012 average for all cultivars in at least some years. ‘Ginger Gold’ exceeded the 2013 NASS average in

2011 and 2013, and in the latter year, all cultivars except Liberty exceeded it. This indicates that top-grafting of existing orchards is an acceptable method for changing cultivars when shifting to organic orchard management in Vermont.

DISEASE AND ARTHROPOD PESTS ON FOLIAGE

Management of disease and arthropod pests was challenging on all cultivars in both orchards, and was expected given that disease and pest management are often cited as impediments to adoption of organic apple production (Delate et al., 2008b, Sayre, 2004,

Earles, 1999, Hinman and Ames, 2011, Zehnder et al., 2007). Results of disease and arthropod pest incidence from individual years were reported in previous publications

(Berkett et al., 2008, Berkett et al., 2013, Berkett et al., 2009b), and comparisons between those studies and the overall means for the six growing seasons 2008-2013 merit further discussion. Although disease and pest incidence was recorded since 2006, data collection in the first two growing seasons did not include several variables that were assessed in later years, and this dissertation does not address those two seasons which were previously reported (Berkett et al., 2008). Data presented in the 2009 publication were included among the multi-year evaluation of disease and arthropod pest incidence in the 2013 publication. The six-year means presented in this paper corroborate the annual results previously presented for a portion of the years in which the research was conducted.

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DISEASE AND ARTHROPOD PESTS ON FRUIT

Annual incidence of disease and insect pest damage on fruit was also reported for

2009-2012 in the 2013 publication referenced above, which may provide greater insight to the grand means reported in this paper. Typical damage from disease, arthropod pest, and abiotic factors (discussed below) is illustrated in Appendix 7. Apple scab incidence on fruit was low in all years, with no mean separation among cultivars in both orchards, except in

Orchard 2 in 2009 when ‘Ginger Gold’ had a higher incidence of scab (13.5%) than all other cultivars except ‘Macoun’, with 3.9% incidence. Those two cultivars were also the highest-ranked in that orchard in the analysis of six-year means. Regarding rust incidence,

‘Ginger Gold’ had the highest or among the highest incidence annually as it also did in the overall six-year mean. Incidence of sooty blotch and fly speck were relatively low annually except for 2009 where ‘Liberty’ and ‘Macoun’ had 7.3% and 5.5% of fruit affected, respectively, in Orchard 1. Fruit rots incidence levels were higher than what would be desired in some years. It is important to note that the grand mean masked variability in the general level of incidence in certain years (Berkett et al., 2013).

The total of all arthropod damage on fruit (i.e., percentage of fruit without any arthropod damage) was significant among cultivars. In the six-year means, no cultivar had greater than 75% of fruit without insect damage, although higher percentages were observed in individual years. Although overall incidence of plum curculio damage across all years was at or below 10%, in some years damage was as high as 23%. Tarnished plant bug damage also was substantially greater in certain years than in the grand mean of all years. . In addition, although ape maggot incidence was less than 1% and no cultivars differences were observed in the six-year means, ‘Honeycrisp’ had 4.8% of fruit with apple

145 maggot damage in 2010 in Orchard 1, although this percentage was not significantly different from the incidence on the other cultivars which was zero. Among the insects directly damaging fruit, it is suspected that internally-feeding lepidopteran pests had the most economic impact because damage is in the form of open wounds where live larvae can remain in the fruit and damaged fruit would be downgraded to the USDA ‘Cull’ grade category which has no economic value. In addition, feeding wounds from internal

Lepidoptera could also become infected by fruit-rotting fungi which may serve as inoculum that could affect adjacent fruit. With both internally-feeding and surface feeding

Lepidopteran pests, the incidence of damage was variable from year to year (Berkett et al.,

2013).

ABIOTIC DAMAGE TO FRUIT

Methods for fruit evaluation at harvest were discussed in Chapter 3, but during that assessment, incidence of abiotic defects was also recorded. These fruit defects may affect the commercial grade of a given fruit, and therefore merit discussion in light of their potential impact on economic performance. As was outlined in Chapter 3, a random, representative sample of 10 fruit per tree in Orchard 1 and 25 fruit per tree in Orchard 2, if available, was collected at harvest and evaluation of fruit defects performed within one week of harvest. Grading defects for each fruit were visually assessed by the observer, who assigned presence/absence for the following defects: sunburn, bitter pit, russet, hail damage, bird pecking, spray injury, frost damage, and fruit cracking. Incidence was recorded as the proportion of fruit affected by each defect. Abiotic defect incidence was averaged for each replicate by cultivar and orchard. Grand means of abiotic damage incidence were calculated across the years 2008-2013 and proportional data transformed

146 by arcsine square root prior to ANOVA with Tukey’s adjustments for multiple comparisons at α=0.05. Results are presented in Table 5.2.

For each defect, significant differences were observed among the cultivars in both orchards, with one exception (i.e., bird pecks in Orchard 1). Sunburn incidence in Orchard

1 was greatest on ‘Honeycrisp’ (4.8%), followed by ‘Zestar!’ (2.7%), which was not statistically different from any other cultivar. In Orchard 2, ‘Zestar!’ had the highest incidence of sunburn with 2.3% of fruit affected. Bitter pit incidence was greatest on

‘Honeycrisp’ in Orchard 1 (3.8%) but in Orchard 2, ‘Macoun’ (6.3%) and ‘Honeycrisp’

(3.4%) both were affected to a greater degree than the other cultivars. Bitter pit is a known problem for both cultivars, and is typically associated with calcium deficiency, nutrient imbalance, heavy crop load and water deficiency (Ferguson and Watkins, 1989), and high incidence may result in poor storability or marketability for those cultivars. Russetting was observed in both orchards. . Hail damage ranged from 13.3% - 20.5% in Orchard 1, and from 8.2% - 13.5% in Orchard 2 in the grand means for 2008-2013, but most damage occurred in 2009 with a lesser amount in 2008, and no hail damage was observed in the remaining years (Table 5.3). Cultivar differences in hail damage incidence may be explained by fruit size, growth habit, or canopy density that may protect fruit from falling hail, but the differences reported do not necessarily suggest that any of the cultivars is more or less susceptible to hail in general. Regarding bird damage, no differences among the cultivars were observed in Orchard 1, but in Orchard 2, ‘Honeycrisp’ fruit were more affected than the other cultivars in that orchard where, in general, crows would commonly roost in the tree tops. Spray burn, most likely caused by a phytotoxic reaction to sulfur or lime sulfur, ranged from 1.0% - 10.4% of affected fruit in Orchard 1 and 0.6% - 4.6% in

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Orchard 2. ‘Honeycrisp’ had the highest incidence of spray burn in Orchard 1, but it was not statistically different from ‘Macoun’. In Orchard 2, both ‘Honeycrisp’ and ‘Liberty’ had the greatest incidence of spray burn. In both orchards, ‘Zestar!’ fruit had the lowest incidence of damage. For frost rings, which were observed in 2010 only, and fruit cracking

‘Honeycrisp’ had the greatest incidence of both in both orchards, with the exception that the incidence of cracking on ‘Macoun’ was not significantly different than ‘Honeycrisp’.

FRUIT GRADE ASSIGNMENT The commercial grade assigned to individual fruit was important in the overall analysis of economic performance of the cultivars in the two orchard systems. Grading was performed following USDA standards used in commercial trade (USDA, 2002), and the same assessor was used for the duration of the project to minimize subjective variation in grade assignment. In addition, the assessor was well-acquainted with grading criteria, with

15 years’ experience in apple grading in commercial and retail environments. The grade categories included in this project were selected to account for relevant and important variations in fruit quality and finish without overwhelming the datasets with extraneous categories. USDA standards include top grades of US#1 Fancy and US#1, but the two are often combined in commercial trade (S. Lacasse, pers. comm.). In addition, the standards specifically allow for combining of the two grades when only the lower US#1 grade is used. Wholesale apples are often sold by ‘count’ size, which roughly equates to the number of fruit of a given size that will fit into a U.S. bushel., with ‘counts’ of 100, 113, 125, 138,

150, and 163 commonly used (Tukey and Schotzko, 1988).

An underlying premise for the economic evaluation of the cultivars in this study was that the hypothetical orchard operator would market the fruit in a retail environment

148 such as an on-farm stand; as such, no storage or packing costs were included. Given that such operations typically do not sort fruit into the number of size categories used by wholesale fruit packers, two categories were selected for US#1 grade fruit. ‘Count’ fruit represented apples that may be sold loose, which customers would select by the individual fruit, and ‘Bag’ fruit which included smaller apples that may be sold in bags by volume or weight. Apples were sorted into the two size categories by fruit weight; and weight thresholds that were used from a published study (Rosenberger et al., 1996) and which were supported by practices used at local retail orchards in the Champlain Valley of

Vermont. For apples that attained US#1 grade, fruit weight of 140 g or greater placed them into the Count category, fruit between 100 and 139 grams were assigned into the Bag category, and fruit under 100 g were included with culled fruit based on the assumption that small fruit may cause problems with processing machinery. A category for ‘Utility’ fruit was included and not sorted by size, based on USDA standards. This grade was assumed to be used in processed apple products such as pies or sauce, and was assumed to be sold directly to the consumer at a significantly lower price or used in on-farm, processing with a lower price assumed in the cost of goods produced. A ‘Cull’ grade was assigned to all fruit under 100 g in size regardless of grade, or to fruit that were significantly damaged or rotten such that they would not meet the Utility standard. USDA grading standards are included in Appendix 8.

Distribution of fruit into grade categories for each cultivar and in each orchard was discussed in Chapter 4. The percent of fruit graded as US#1 Count for each cultivar in both orchards when averaged across the years of the study was below commercial standards used for non-organic fruit. Tukey and Schotzko (1988) recommend ‘packout’ (a term that

149 refers to the relative percentage of fruit that is graded as US#1 or higher) levels of 90-95% for commercial wholesale orchards in the Pacific Northwest, and those values are supported by packing house operators in the Champlain Valley of Vermont (S. Lacasse, D.

Greene, pers. comm.). Annual percent of fruit assigned to each grade category for all cultivars in both orchards is illustrated in Figure 5.3. In many years, less than 50% of fruit of each cultivar were in the combined US#1 Count and Bag grades. In 2008, all cultivars in both orchards except ‘Zestar!’ in Orchard 2 had greater than 50% US#1 fruit, but in

2009, all had dropped below that level and most remained below 50% for the duration of the study. As stated above, overall, the proportion of fruit in the US#1 grades was below the 90-95% considered acceptable for non-organic orchards. The low proportion of fruit in the US#1 grades was an important factor for all cultivars in both orchards in evaluation of their economic performance in this study.

ECONOMIC EVALUATION

Input costs

Detailed annual labor, equipment, and input costs by category are presented in

Appendix 9. In this study, meticulous records of all orchard activities were collected, and all production activities were included in the cost tables. Data collection and other experimental procedures unique to a research project were coded as such, and those activities were not included in the data. Further detail on specific activities and specific inputs is not included in the tables is order to summarize costs more concisely. Costs in

Orchard 1 began to accrue at the time of removal of the previous orchard (2003), in order to fully assess the impact of those activities on long-term economic performance. In

Orchard 2, costs began to accrue in 2006 when top-grafting was performed. A more

150 complete analysis including costs and returns in 2003-2005 for Orchard 2, which had harvestable crop produced on mature trees during those years, would favor the economic performance of that orchard substantially.

All labor activities were coded as unskilled or skilled, and wages per hour of US$10 and US$25 per hour assigned, respectively. Insurance and other benefits were not included separately in the cost data. Skilled activities were those that would be performed by a manager or owner with extensive experience in orchard management, and unskilled activities were those that may be provided by seasonal labor. Labor costs, on average, made up 29% and 33% of total costs over the duration of the study in Orchards 1 and 2 respectively. However, high labor costs for hand weeding in Orchard 1 in certain years were important factors in those years where labor costs were 63% (2007) and 58% (2010) of total costs. The efficiency of field workers in those years and extent to which the orchard was hand weeded likely disproportionately impacted economic performance compared to horticultural benefits achieved. Given the high labor costs associated with hand weeding, a commercial grower of organic apples may not likely use that practice after the initial planting year. Improved mechanical weeding procedures could reduce management costs, but a critical point to consider is the need to maintain a weed-free strip to reduce competition for nutrients and water between groundcover and trees in early establishment years. This is an area where further research is merited. In Orchard 2, labor costs in excess of 35% of total costs only occurred in the initial grafting year, and reflected the labor required to cut the original trees down to grafting height, perform grafting, and train the newly growing scions.

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In this study, all equipment costs including hand tools were included. For some equipment uses, a value of $0 or $1 appears in the table. This is not a typographic error, but represents very low costs for the hourly use of hand tools for infrequent tasks. Overall equipment costs were $35,894 and $18,785 for Orchard 1 and 2, respectively, with spraying equipment costs having the greatest share of total equipment costs (23% and 25% in Orchards 1 and 2, respectively) in each orchard.

Compared to labor and equipment costs, applied inputs made up the greatest percentage of total costs in both orchards over the duration of the experiment (i.e, 48% and

42% for Orchards 1 and 2, respectively). In particular, the costs associated with the establishment of Orchard 1, including trees and trellis materials, were notably high. High establishment costs of modern high-density orchards are not unique to organic systems, and a general figure of $50,000 per hectare is assumed, compared to as low as $12,000 for lower density systems without the need for a trellis (Robinson et al., 2007). The high initial cost of orchard establishment requires early and high yield in order to recoup invested funds, and in Orchard 1, that was not achieved.

Because all cultivars within each orchard were given the same management so that the cultivar was the experiment treatment in this study, costs described above were considered fixed costs in that they did not vary by cultivar. Labor costs associated with hand thinning fruit, however, were variable by cultivar depending on the time required to manually thin the crop on each tree. Hand thinning was not performed in either orchard in

2008 because the crop was relatively small, as discussed in Chapter 2. In 2009 and 2010, hand thinning was also not performed in Orchard 1 in order to assess the effects of kelp- derived biostimulants extracts on the efficacy of lime sulfur fungicides (Bradshaw et al.,

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2013) which, although not specifically labeled as thinners, have been shown to provide fruit thinning when used for apple scab management from bloom through 10-12 mm fruit size (McArtney et al., 2006, Noordijk and Schupp, 2003, Stopar, 2004). No effects from kelp-extract application on thinning effectiveness nor return bloom were observed in the study (Bradshaw et al., 2013). Hand thinning was performed in Orchard 1 in 2011-2013 and in 2009-2013 despite the application of oil and liquid lime sulfur at petal fall in each year. On all trees, fruit were selectively removed in June soon after fruit set or around 10-

20 mm in size. Thinning was performed to reduce fruit to one fruit per cluster, and insect- damaged fruit were selectively removed and disposed.. Laborers recorded the time to thin each tree in minutes, and those values were multiplied by labor rates to assign a thinning cost for each tree. Costs were standardized to $/ha based on planting density for inclusion in the cost and net income analysis in this study. Annual thinning costs (Table 5.4) were subjected to ANOVA with Tukey’s adjustment for multiple comparisons applied. In

Orchard 1, ‘Ginger Gold’ had the highest thinning cost in 2011 followed by ‘Honeycrisp’, with no difference among the remaining cultivars. . Cultivar differences were less distinct in 2012. In 2013, ‘Honeycrisp’ had the highest thinning cost among all cultivars at

$1,545/haIn Orchard 2, ‘Ginger Gold’ was always the highest or among the highest for thinning costs, and ‘Macoun’ and ‘Zestar!’ often among the lowest. The labor required to hand thin fruit in this study was not insubstantial, and further research on cost-effective and horticulturally-effective thinning treatments in organic orchards is warranted.

Income

Central to the economic evaluation of any enterprise is a review of income generated by the business. In this study, harvested crop yield was multiplied by the

153 percentage of fruit in each grade category, and the resulting values multiplied by assigned prices for each grade. Thus, the two primary determinants of income are yield and grade distribution, with higher yield and increased sorting of fruit into US#1 grades positively affecting income. In 2007, a small crop of fruit from the original scion cultivar in Orchard

2 was harvested from ‘nurse limbs’, which were scaffold limbs retained in the year after top-grafting in order to maintain photosynthesis and tree growth of the tree. That crop was not produced from the evaluated scion cultivars in this study, but was graded to the same standards and included in the income evaluation, because commercial growers commonly produce fruit on nurse limbs to maintain cash flow. In order to concentrate growth into the developing top-grafted scions, no fruit were retained in 2006, so no income is shown in that year. In 2008, both orchards were allowed to crop on the scion cultivars evaluated in this study.

Annual income by cultivar and orchard, expressed in $/ha, is presented in Table

5.5. In Orchard 1, ‘Liberty’ had the highest gross income among the cultivars in 2008, which may be expected because it also produced the highest harvested crop yield in that year and over 70% of fruit were assigned US#1 grades (Table 2.2, Chapter 2). Similarly, the highest-yielding cultivar in 2009 in that orchard, ‘Honeycrisp’, also had the highest income. In 2010, despite crop yield that was not significantly different from the other cultivars, income for ‘Ginger Gold’ was the highest. Gross income has highest for

‘Honeycrisp’ and ‘Ginger Gold’ in 2011 and lowest for ‘Liberty and ‘’Zestar!’. In 2013, no differences were observed among cultivars for gross income, and the values for all cultivars were the highest among all years in the study.

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In Orchard 2, differences in income were observed in 2007; the fruit harvested were from the ‘nurse limbs’ of the original cultivars (i.e., ‘Liberty’ and ‘McIntosh’) that were retained and not from the newly grafted scions. ‘Ginger Gold’ was the highest or among the highest cultivars for gross income in all years except 2012, when ‘Liberty’ and

‘Honeycrisp’ had the greatest income. ‘Macoun’ and ‘Zestar!’ had the lowest or among the lowest gross income for 2008-2013, presumably because of poor tree survival for those cultivars.

Net present value

The net present value (NPV) analysis discussed in Chapter 4 represents the primary evaluation of the long-term potential for the cultivars in this study to be grown successfully for profit in each organic management system. Comparisons in this study were not made to a non-organic treatment, but rather the cultivars were evaluated against one another within each system to assess cultivar selection when best organically-acceptable management practices were applied to all. Actual, measured data were used for crop yield, fruit grade category distribution, and management costs for all years through 2013, but for

2014 through 2015, those values were extrapolated from means of the previous four years when the orchards were assumed to be in full production. Costs were not adjusted for inflation for future years, which may bias the results toward greater profitability than expected, but fruit price was also not adjusted upward in projections. The four-year means for costs and income represent “best-guess” values based on long-term establishment of the orchard systems. Production in the later years may be expected to decline as trees age, but that was not taken into consideration because a twenty-year lifespan is generally on the lower end of an orchard’s productive lifespan (Westwood, 1993).

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All cultivars in Orchard 1 had negative NPV after year 20, and continued annual losses in value occurred for all projected years (reference table in Chapter 4) . The high establishment and management costs in this orchard simply were not recouped by yield or fruit grade during the study, and it is not expected that any additional future changes in management would affect NPV sufficiently to consider this orchard economically successful. In Orchard 2, positive NPV was attained after twenty years for all cultivars; reduced tree survival was a likely cause of lower NPV for ‘Macoun’ and ‘Zestar!’. That positive NPV was achieved in this orchard suggests that, given adequate tree vigor and resulting crop production, organic apple production can be successful with the cultivars of this study in a top-grafted orchard establishment system in the region. Given these results, one can speculate that changes in the fundamental orchard design of Orchard 1, such as using a more vigorous rootstock, which would increase tree growth and crop yield in the newly planted orchard, may have led to successful economic performance in that system also.

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161

TABLES AND FIGURES

Table 5.1 Annual harvested crop yield, MG/ha.

29.23

29.45

19.52

26.45

42.21

15.63

10.07

10.87

18.36

13.66

2013

5.40

5.30

9.79

3.64

5.74

1.87

2.57

2.04

18.20

15.76

2012

9.44

4.33

5.42

4.97

8.54

19.74

12.37

17.40

25.19

10.04

2011

2.51

7.66

5.93

2.39

1.52

0.66

0.80

1.82

10.16

11.73

2010

6.68

2.33

2.78

3.70

5.62

8.11

2.89

13.60

10.00

13.03

2009

z

1.09

0.48

2.81

1.65

0.21

0.39

1.10

0.05

0.06

10.33

2008

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Values represent annual mean yield per hectare calculated from kg fruit per tree each fruit from and orchard.in kg tree per density Dead hectare calculated mean represent yield annual Values

studies, no statistics were performed. no studies, statistics

trees were assigned yield of zero to account yield for tree trees death. were similar presented assigned purposes Data for with is comparison

z Orchard Orchard 2 Orchard Orchard 1

162

Table 5.2 Mean percent incidence of abiotic fruit defects, 2008-2013

c

b

bc

a

c

c

ab

c

a

bc

1.5

3.5

1.9

5.4

1.1

1.0

2.6

0.8

6.0

1.2

<0.0001

<0.0001

Cracking

b

b

b

a

b

b

b

b

a

b

0.1

0.0

0.2

1.0

0.0

0.0

0.0

1.2

5.1

0.0

<0.0001

<0.0001

Frost Frost ring

c

b

a

b

a

c

ab

b

b

a

0.6

1.7

4.4

2.4

4.6

1.0

8.1

5.2

5.7

10.4

<0.0001

<0.0001

Spray Spray burn

b

b

b

a

b

4.1

2.2

2.6

7.8

4.0

1.6

1.1

1.1

2.7

1.7

0.0777

<0.0001

Bird pecks Bird

a

b

a

b

b

ab

c

ab

bc

a

8.6

8.2

9.0

13.4

13.5

16.3

13.3

17.9

15.1

20.5

Hail

<0.0001

<0.0001

a

ab

bc

c

a

b

a

ab

bc

a

8.4

5.2

4.5

2.7

6.1

6.3

8.1

7.0

3.1

8.8

0.0002

Russet

<0.0001

b

a

b

a

b

b

b

b

a

b

0.5

6.3

0.7

3.4

0.0

0.2

1.2

0.8

3.8

0.0

<0.0001

<0.0001

Bitter pit Bitter

z

a

b

b

b

b

ab

b

b

a

b

2.3

0.9

0.3

1.5

0.2

2.7

0.5

0.1

4.8

1.4

<0.0001

<0.0001

Sunburn

y

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

P-value for overall F-test to detect differences among culivars for grade. each fruit culivars F-test to among detect P-value for differences overall

Values represent grand mean of annual means from 2008-2013 for percent of fruit evaluated at harvest with incidence of abiotic defects. was of mean Incidence means represent abiotic of from grand annual 2008-2013 at for incidence percent harvest Values evaluated of with fruit

y

cultivar.

by the same lower-case letter within a column do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for by do mean a at not separation column differ α=0.05.applied by within Tukey's comparisons the letter same lower-case adjustment for multiple

calculated from the number of fruit affected / total of all fruit evaluated (10 per tree in Orchard 1, 25 per tree in Orchard 2, if available). Values followed followed (10 per evaluated Orchard tree 1,from fruit Values in the number 25 affected of of per / Orchard fruit calculated all tree total 2,in available). if

z Orchard Orchard 2 Orchard Orchard 1

163

Table 5.3 Mean annual percent incidence of hail damage on fruit, 2008-2013 2008 2009 2010 2011 2012 2013 Orchard 1 Ginger Gold 25.0 z 87.2 ab 0.0 0.0 0.0 0.0 Honeycrisp 0.0 62.1 d 0.0 0.0 0.0 0.0 Liberty 5.5 89.3 a 0.0 0.0 0.0 0.0 Macoun 2.4 75.5 cd 0.0 0.0 0.0 0.0 Zestar! 6.5 76.0 bc 0.0 0.0 0.0 0.0 cultivar (p)y 0.1304 <0.0001 na na na na

Orchard 2 Ginger Gold 0.5 ab 53.3 b 0.0 0.0 0.0 0.0 Honeycrisp 0.0 a 46.7 b 0.0 0.0 0.0 0.0 Liberty 3.7 ab 72.3 a 0.0 0.0 0.0 0.0 Macoun 7.5 ab 50.5 b 0.0 0.0 0.0 0.0 Zestar! 8.4 b 70.7 a 0.0 0.0 0.0 0.0 cultivar (p) 0.0092 <0.0001 na na na na zValues represent annual means from 2008-2013 for percent of fruit evaluated at harvest with incidence of hail damage. Incidence was calculated from the number of fruit affected / total of all fruit evaluated (10 per tree in Orchard 1, 25 per tree in Orchard 2, if available) Values followed by the same lower-case letter within a column do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for mean separation by cultivar. yP-value for overall F-test to detect differences among culivars for each fruit grade.

164

Table 5.4: Annual costs (US$/ha) for hand thinning fruit, 2009-2013 2009 2010 2011 2012 2013 Orchard 1 Ginger Gold naz na $ 912 ay $ 207 ab $ 677 b Honeycrisp na na $ 633 b $ 305 ab $ 1,545 a Liberty na na $ 299 c $ 158 b $ 663 b Macoun na na $ 313 c $ 343 a $ 755 b Zestar! na na $ 264 c $ 257 ab $ 414 b cultivar (p)x <0.0001 <0.0001 <0.0001

Orchard 2 Ginger Gold $ 3,091 a $ 2,512 a $ 3,508 a $ 903 ab $ 3,007 a Honeycrisp $ 780 c $ 1,540 bc $ 1,774 b $ 1,491 a $ 3,072 a Liberty $ 1,777 b $ 2,267 ab $ 1,172 bc $ 1,462 a $ 1,601 bc Macoun $ 466 c $ 1,151 c $ 1,214 bc $ 584 b $ 2,862 ab Zestar! $ 489 c $ 1,317 c $ 995 c $ 521 b $ 1,118 c cultivar (p) <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 zNo hand thinning performed in Orchard 1 in 2009 or 2010. yValues represent annual means from 2009-2013 for labor costs (at US$10/hr) to hand-thin fruit to one apple per cluster in June. Values followed by the same lower-case letter within a column do not differ at α=0.05. Tukey's adjustment for multiple comparisons applied for mean separation by cultivar. x P-value for overall F-test to detect differences among culivars for each fruit grade.

165

Table 5.5: Annual gross income (US$/ha) for harvested fruit, 2007-2013.

b

b

b

b

a

2013

0.0001

0.0672

27,676

34,495

34,798

28,648

71,307

17,947

13,752

12,253

18,433

20,141

$

$

$

$

$

$

$

$

$

$

c

c

a

ab

bc

b

a

bc

c

c

2012

4,984

4,658

4,419

7,516

2,957

2,177

2,238

0.0001

0.0001

30,116

19,735

14,412

$

$

$

$

$

$

$

$

$

$

b

b

b

b

a

c

bc

c

a

ab

2011

7,712

8,891

6,252

0.0001

0.0001

17,966

16,909

12,857

22,454

42,654

13,255

11,700

$

$

$

$

$

$

$

$

$

$

bc

c

ab

c

a

b

b

b

b

a

2010

7,152

2,809

3,627

2,498

2,489

1,273

1,122

5,224

0.0001

0.0001

10,456

15,157

$

$

$

$

$

$

$

$

$

$

c

c

ab

b

a

c

bc

bc

a

b

2009

7,153

3,485

3,333

5,171

5,509

6,831

0.0001

0.0001

21,406

16,121

23,248

11,248

$

$

$

$

$

$

$

$

$

$

y

b

b

b

b

a

bc

b

a

bc

c

804

440

921

222

150

2008

1,280

6,113

3,372

2,466

0.0001

0.0001

22,114

$

$

$

$

$

$

$

$

$

$

ab

a

ab

b

ab

z

na

na

na

na

na

2007

5,436

6,125

4,207

2,507

3,450

0.0028

$

$

$

$

$

x

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

cultivar (p) cultivar

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Values represent annual mean gross income for 2007-2013. Income was calculated by kg harvested fruit / for harvested by tree 2007-2013.fruit income kg (dead mean represent Income trees gross annual was assigned calculated Values

No crop was produced in Orchard 1 in 2007. Fruit harvested in 2007 in Orchard 2 was from nurse limbs held over from the original tree No crop was over Orchard Orchard produced 2007. 2007 from 1 2 harvested held in in the in in was Fruit original from nurse limbs

P-value for overall F-test to detect differences among culivars for grade. each fruit culivars F-test to among detect P-value for differences overall

x

Tukey's adjustment for multiple comparisons applied for by mean cultivar. separation applied Tukey'scomparisons adjustment for multiple

US$0.52; and Cull: US$0.00 per kg , respectively Values followed by the same lower-case letter within a column do a at not column differ α=0.05. by within the letter same lower-case followed Values US$0.00 ,per kg US$0.52;respectively and Cull:

yield=0) * fruit grade distribution * price per grade. Assumed crop prices were: US#1 Count: US$3.14; US#1 Bag: US$2.10; Utility: US$2.10; US$3.14; US#1 Utility: Count: US#1 were: crop Bag: per prices * Assumed grade. price distribution grade * fruit yield=0)

y

produced from the new, grafted cultivar in produced that from in orchard. the new, cultivar grafted

cutlivar ('McIntosh' were subsequent fruit cutlivar were of 2008 2006.removed to 'Liberty')and was in in all grafted Nurse which limbs

z Orchard Orchard 2 Orchard Orchard 1

166

Figure 5.1: Trunk cankers on dead trees, Orchard 2

Left: Trunk canker and bark peeling on dead ‘Macoun’ tree. Right top: Discolored heartwood on stump at grafting may indicate presence of wood-rotting fungi. Right bottom: Bract fungi on declining ‘Macoun’ tree.

167

Figure 5.2: Size of typical trees in Orchard 1

Photos of typical tree size in Orchard 1, fall 2012. Clockwise from upper left: ‘Macoun’ (left) and ‘Ginger Gold’; ‘Liberty’; ‘Honeycrisp’, and; ‘Zestar!’.

168

Figure 5.3: Annual fruit grade distribution, 2008-2013

Annual mean distribution of fruit into four commercial grades by cultivar. In each year, 10 (Orchard 1) or 25 (Orchard 2) fruit per tree, if available, were evaluated within one week of harvest for fruit weight, red color, disease and pest damage incidence, and abiotic defects. Each fruit was then assigned a grade according to commercial standards (USDA 2002). ‘USDA 1’ grades represent USDA #1 or greater, and are the highest-valued fruit.

169

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APPENDICES

APPENDIX 1: THE RATIONALE AND MAJOR OBJECTIVE IN THE USDA GRANTS THAT FUNDED THE ‘ORGANICA PROJECT’ INCLUDING THE LIST OF INVESTIGATORS Major Funding Sources: USDA Integrated Organic Program (IOP) Grant: “Using ‘New’ Alternatives to Enhance Adoption of Organic Apple Production through Integrated Research, Education, and Extension” (USDA CSREES 2006-51300-03478, 2006-2009). USDA Organic Research & Extension Initiative (ORE) Grant: “Using ‘New’ Alternatives to Enhance Adoption of Organic Apple Production through Integrated Research and Extension” (USDA CSREES 2009-51300-05530, 2009-2014). Principle Research Investigators and Key Technical Specialists: University of Vermont: Lorraine P. Berkett, Robert L. Parsons, Heather M. Darby, Terence L. Bradshaw, Sarah L. Kingsley-Richards, and Morgan C. Griffith University of Arkansas: M. Elena Garcia University of Maine: Renae E. Moran Rationale (from 2006 grant proposal, but without citations): The public views organic agriculture as highly related to safe food systems, a healthy, well-nourished population, and an agricultural system that protects the environment. A strong, sustainable agriculture is critical to the viability of rural communities, including the positive impact of the agricultural landscape on tourism. This is particularly important in Vermont where most of its population lives in rural communities and to other rural states. Apples (Malus x domestica Borkh) are an important component of New England’s diversified agriculture. In New England, the crop represents 7,700 ha, with an average utilized production value for the past ten years of 47 million dollars. In Vermont, there are currently approximately 3,000 acres (1,215 ha) which generate $8.9 million in annual cash receipts and $12.8 million in value-added products. Maine currently has 2,220 acres (898 ha) in commercial apple production based on University of Maine surveys and production records of the Maine State Pomological Society. However, out of the estimated 1,421 commercial apple orchards in New England, very few are certified organic. In Vermont, there are only three certified commercial apple orchards; in Maine, there are seven organic orchards ranging in size from one to 120 acres ( 0.4- 49 ha). More orchardists are interested in organic production than this number reflects and have asked for research and extension outreach on organic apple production for many years (1998 through 2005 University of Vermont (UVM) Apple Industry Surveys, unpublished). In Maine, requests to the University of Maine Cooperative Extension for information on organic apple growing averaged 11% of the total requests during the years 2001-2005 (Moran, personal communication). However, a major constraint to organic production has been the susceptibility of the predominant cultivar grown in the New England region (i.e., ‘McIntosh’) to apple scab, a

189 serious disease caused by the fungus Venturia inaequalis (Cooke) Wint. which can make the fruit unmarketable as fresh fruit and which can weaken the overall health of the tree by affecting photosynthesis and causing premature defoliation. ‘McIntosh’ apple trees are considered very susceptible to apple scab and wet, cool conditions that occur in New England during the growing season favor apple scab infection and disease development. Thus, production of quality fruit relies on multiple applications of fungicides (i.e., 8-10+ applications). Recently, within the apple industry in New England there has been a shift away from ‘McIntosh’ because of consumer preference for different cultivars and a shift in market focus from wholesale to more profitable retail, niche markets. ‘McIntosh’ currently comprises approximately 42% of the total apple production in Vermont; in 1992, it was 62%. In 1998, 66% of orchards responding to an industry survey were classified as retail or retail/wholesale operations. The same survey in 2003 indicated this number to be 76%. The number of wholesale operations decreased from 13% in 1998 to 9% in 2003. In terms of trends in local, niche-markets, 6.3 million dollars in agricultural products were sold directly to consumers through farmers’ markets in Vermont in 1997. This amount increased to 45 million dollars by 2003. In Maine, a similar trend has occurred. Average farm size decreased from 30 acres (12 ha) in 2001 to 22 acres (9 ha) in 2005, as growers reduced wholesale production and increased the retail/farmstand portion of their market based on University of Maine surveys and production records of the Maine State Pomological Society. On the national level, the shift in cultivar preference is reflected in the fact that most of the fresh market apples now being imported into the United States (US) are newer cultivars whose fruit have distinctive color, flavor, and quality characteristics. Of the eighteen apples featured in the US Apple Association web page, six are more recent introductions into the US. The change in cultivar preference in national markets has also occurred in local and regional markets where consumers are seeking newer cultivars. This trend has a distinct advantage for enhancing organic agriculture in the region because: (1) many of these cultivar alternatives are more naturally resistant to apple scab and can be grown with fewer fungicides plus advances in scab research make management of this disease more feasible on these newer cultivars; and (2) the trend allows for the strengthening of local/regional, niche-market strategies that potentially provide higher profit margins. New apple cultivars, such as ‘Honeycrisp’ and ‘Ginger Gold’, bring a premium price to apple growers in local and regional markets. ‘Honeycrisp’ when sold at retail markets can sell for up to $50.00 per bushel (ungraded) whereas, ‘McIntosh’, graded to USDA standards, sells for an average of $18.00 to $22.00 per bushel. The price premium for new cultivars over standard cultivars may last 10-15 years. Some of the newer cultivars, such as ‘Honeycrisp’, ‘Ginger Gold’, and ‘Zesta!’ are particularly adapted to the colder climate of New England and northeastern New York and grow better here than in other warmer regions, furthering the potential for capturing niche-markets. It is expected that organically grown apples would have economic benefits to growers throughout the region are expected to reduce the farm’s marketing and financial risk. Would not scab-resistant apple cultivars address the scab disease constraint? Yes is the answer but, currently available scab-resistant cultivars do not have the consumer appeal that other new cultivars have. This is associated with many reasons, some of which are outlined in the Final Report of an extensive, eight-year USDA LISA/SARE Apple Production Project. This multi-disciplinary project, which involved growers from NJ, PA,

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NY, MA and VT and researchers and/or extension personnel from the Rodale Institute, Rutgers University, Cornell University, the Universities of MA and VT evaluated how scab-resistant cultivars (SRCs) could contribute to more sustainable production systems. [Note: Dr. Berkett was the coordinator of the project for five years.] The study noted that although small, niche-markets for SRCs have been established by some growers, they did not have the name recognition and consumer appeal of other newly introduced cultivars. None of the SRCs that were evaluated had as distinctive and desirable fruit quality attributes as those found in other recent introductions like ‘Ginger Gold’ and, more recently, ‘Honeycrisp’. This is not to say that SRCs should be forgotten; they are an important cultivar alternative in organic production and are represented in the proposed research. Another major constraint in organic apple production was arthropod management, in particular management of the plum curculio, Conotrachelus nenuphar (Herbst). Research on alternative management strategies for this arthropod pest and others including biocontrol of the European red mite, Panonychus ulmi (Koch), by the predacious mite, Typhlodromus pyri (Scheuten), provide insights and potential alternatives to managing pest populations within organic apple systems. In addition, a kaolin clay product has been shown to suppress many of the arthropod pests of apple. As with any new technology, potential non-target impacts within the apple ecosystem must be identified, however, kaolin remains a viable organic option to suppress key arthropod pests of apple if used judiciously. A third major constraint in organic apple production has been the availability of practical thinning methods. Chemical thinning of apples is one of the most important management practices that an orchardist is required to do. It is conducted to adjust fruit load, to increase fruit size, and to enhance return bloom because the economic viability of most orchards depends on the production of large, high quality fruit every year. Orchards managed under conventional or IPM practices depend on the use of plant growth regulators and carbaryl (an organophosphate insecticide) to accomplish this task. These conventional thinners are not available for use in organic systems and thinning has been done by hand. In Washington State, the lack of traditional thinners for use in organic apple production is reported to be one of the reasons for the higher production costs associated with organic apple systems. Hand thinning in organic orchards can account for 10 to 20 percent of the total labor budget in an orchard. Recent research in the development of thinning strategies for use in organic apple orchards has resulted in promising alternatives such as fish oil and lime sulfur applications. The implementation of these findings into organic apple systems has the potential to solve a major limitation in organic apple production. From a number of perspectives, it is an opportune time to conduct the integrated organic apple research, education, and extension that is being proposed in this grant application. Research knowledge related to what were the major constraints in adoption of organic production in the Northeast is at a point where it needs to be integrated into organic production systems and evaluated holistically, including an economic analysis of potential economic costs, returns, and risks associated with the systems. Growers want and have asked for organic research and information which will facilitate decision-making on the opportunities and risks of organic apple production. To date, we have not been able to adequately address their needs.

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We propose to establish two organic apple orchards which represent the way growers would change cultivars on their farm: (1) either by planting a new orchard where young trees ordered from a nursery are planted; and (2) by using a technique called “top- grafting” whereby twigs containing several vegetative buds of the new cultivar (scion) are grafted onto the trunk of an existing, older tree changing the cultivar of the tree. We will incorporate available knowledge and information to evaluate cultivar performance in these organic apple production systems; the research will address consumer preferences for newer cultivars and organically grown food, and grower desires for sustainability and profitability.

The Major Research Objective of the OrganicA Project: Incorporate and evaluate ‘new’ apple cultivars and research-generated knowledge of apple ecosystem dynamics into organic production systems to determine sustainability and profitability. In essence, the questions being researched in this project are:

 What are the opportunities and challenges of five apple cultivars identified as important to apple industry under organic apple production?  Is organic apple production profitable and sustainable with the knowledge and tools we have and with these cultivars?  Will there be a long-term difference in profitability between the two organic apple production systems growers are using to switch to new cultivars?

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APPENDIX 2: ORCHARD MAPS

OrganicA Project, Orchard 1 UVM Horticultural Research Center, South Burlington Vermont This orchard is a new planting. The previous orchard was removed in 2003 and soil was prepared prior to planting the new trees in 2006. For research purposes, the orchard is planted in a completely randomized design with replications of 5 cultivars (‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’, ‘Macoun’, and ‘Zestar!’).

SOUTH KEY 35 C3E C5W 35 code definition 34 C2E C4W 34 C1 Ginger Gold/Bud.9 33 C5E C2W 33 C2 Honeycrisp/M.26 32 (skip) C1W 32 C3 Liberty/Bud.9 31 C1E C3W 31 C4 Macoun/Bud.9 30 C4R14T3 C1R2T3 C5R4T3 C2R6T3 C1R8T3 C2R11T3 C5R12T3 C3R16T3 30 C5 Zestar!/Bud.9 29 C4R14T2 C1R2T2 C5R4T2 C2R6T2 C1R8T2 C2R11T2 C5R12T2 C3R16T2 29 R1 rep 1 28 C4R14T1 C1R2T1 C5R4T1 C2R6T1 C1R8T1 C2R11T1 C5R12T1 C3R16T1 28 R2 rep 2 27 C1R15T3 C3R1T3 C4R4T3 C1R5T3 C4R9T3 C5R10T3 C4R12T3 C5R16T3 27 R3 rep 3 26 C1R15T2 C3R1T2 C4R4T2 C1R5T2 C4R9T2 C5R10T2 C4R12T2 C5R16T2 26 R4 rep 4 25 C1R15T1 C3R1T1 C4R4T1 C1R5T1 C4R9T1 C5R10T1 C4R12T1 C5R16T1 25 R5 rep 5 24 C3R14T3 C5R2T3 C3R5T3 C5R7T3 C3R7T3 C1R10T3 C5R11T3 C4R16T3 24 R6 rep 6 23 C3R14T2 C5R2T2 C3R5T2 C5R7T2 C3R7T2 C1R10T2 C5R11T2 C4R16T2 23 R7 rep 7 22 C3R14T1 C5R2T1 C3R5T1 C5R7T1 C3R7T1 C1R10T1 C5R11T1 C4R16T1 22 R8 rep 8 21 C2R14T3 C2R3T3 C1R3T3 C3R6T3 C5R9T3 C3R9T3 C3R12T3 C2R16T3 21 R9 rep 9 20 C2R14T2 C2R3T2 C1R3T2 C3R6T2 C5R9T2 C3R9T2 C3R12T2 C2R16T2 20 R10 rep 10 19 C2R14T1 C2R3T1 C1R3T1 C3R6T1 C5R9T1 C3R9T1 C3R12T1 C2R16T1 19 R11 rep 11 18 C5R13T3 C4R2T3 C4R3T3 C1R4T3 C4R8T3 C2R10T3 C1R12T3 C1R16T3 18 R12 rep 12 17 C5R13T2 C4R2T2 C4R3T2 C1R4T2 C4R8T2 C2R10T2 C1R12T2 C1R16T2 17 R13 rep 13 16 C5R13T1 C4R2T1 C4R3T1 C1R4T1 C4R8T1 C2R10T1 C1R12T1 C1R16T1 16 R14 rep 14 15 C2R13T3 C1R1T3 C3R4T3 C4R6T3 C5R8T3 C1R9T3 C3R11T3 C5R15T3 15 R15 rep 15 14 C2R13T2 C1R1T2 C3R4T2 C4R6T2 C5R8T2 C1R9T2 C3R11T2 C5R15T2 14 R16 rep 16 13 C2R13T1 C1R1T1 C3R4T1 C4R6T1 C5R8T1 C1R9T1 C3R11T1 C5R15T1 13 T1 North tree 12 C1R14T3 C2R2T3 C5R3T3 C2R5T3 C2R7T3 C2R9T3 C4R11T3 C2R15T3 12 T2 middle tree 11 C1R14T2 C2R2T2 C5R3T2 C2R5T2 C2R7T2 C2R9T2 C4R11T2 C2R15T2 11 T3 South tree 10 C1R14T1 C2R2T1 C5R3T1 C2R5T1 C2R7T1 C2R9T1 C4R11T1 C2R15T1 10 9 C3R13T3 C4R1T3 C3R3T3 C5R6T3 C1R7T3 C3R8T3 C1R11T3 C5R14T3 9 8 C3R13T2 C4R1T2 C3R3T2 C5R6T2 C1R7T2 C3R8T2 C1R11T2 C5R14T2 8 7 C3R13T1 C4R1T1 C3R3T1 C5R6T1 C1R7T1 C3R8T1 C1R11T1 C5R14T1 7 6 C4R13T3 C5R1T3 C2R4T3 C4R5T3 C1R6T3 C2R8T3 C2R12T3 C4R15T3 6 5 C4R13T2 C5R1T2 C2R4T2 C4R5T2 C1R6T2 C2R8T2 C2R12T2 C4R15T2 5 4 C4R13T1 C5R1T1 C2R4T1 C4R5T1 C1R6T1 C2R8T1 C2R12T1 C4R15T1 4 3 C1R13T3 C2R1T3 C3R2T3 C5R5T3 C4R7T3 C4R10T3 C3R10T3 C3R15T3 3 2 C1R13T2 C2R1T2 C3R2T2 C5R5T2 C4R7T2 C4R10T2 C3R10T2 C3R15T2 2 1 C1R13T1 C2R1T1 C3R2T1 C5R5T1 C4R7T1 C4R10T1 C3R10T1 C3R15T1 1 ROW 1 ROW 2 ROW 3 ROW 4 ROW 5 ROW 6 ROW 7 ROW 8 NORTH METHODS Trees planted 4/21/06 by Lorraine Berkett, Terry Bradshaw and Sarah Kingsley-Richards Trees repositioned 4/27/06 by Terry Bradshaw and Sarah Kingsley-Richards Reps 1-12 start in row 2 and continue through row 7 Reps 13-16 start in row 1 and go to row 8 All rep counting goes from North to South in each row Tree code verified on 5/23/06 by Sarah Kingsley-Richards

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OrganicA Project, Orchard 2 (2008) UVM Horticultural Research Center, South Burlington Vermont SOUTH B2C3 extra B2C3 extra B2C3 extra 71 ?C2 B1C3 extra B2C2R19T2 71 This orchard is a top-grafted orchard. Trees in an existing 70 B2C3 extra B1C3 extra B2C2R19T1 70 orchard (‘McIntosh’ and ‘Liberty’ trees on M.26 rootstock 69 ?C2 (skip) B2C2R18T2 69 68 ?C2 B1C3 extra B2C2R18T1 68 planted in 1988) were cut back to a trunk and “nurse” limb 67 ?C2 B1C3 extra B2C3 extra 67 prior to grafting of scions in April 2006. For research 66 ?C2 B1C3 extra (skip) 66 purposes and to block any existing cultivar effect on new 65 B2C1R12T2 B1C1R6T2 B2C1R19T2 65 scion growth, the orchard is grafted in a randomized 64 B2C1R12T1 B1C1R6T1 B2C1R19T1 64 63 B2C1R11T2 B1C5R5T2 B2C5R19T2 63 complete block design with replications of 5 cultivars 62 B2C1R11T1 B1C5R5T1 B2C5R19T1 62 (‘Ginger Gold’, ‘Honeycrisp’, ‘Liberty’, ‘Macoun’, and 61 B2C4R11T2 B1C3R7T2 B2C4R19T2 61 ‘Zestar!’). A total of 19 two-tree replicates per cultivar 60 B2C4R11T1 B1C3R7T1 B2C4R19T1 60 were top-grafted across the entire orchard. The number of 59 B2C3R14T2 B1C2R6T2 B2C1R18T2 59 58 B2C3R14T1 B1C2R6T1 B2C1R18T1 58 scions grafted PER TREE was dependent on rootstock 57 B2C2R12T2 B1C4R6T2 B2C3R19T2 57 diameter, where <6 inches received two scions and >6 56 B2C2R12T1 B1C4R6T1 B2C3R19T1 56 inches received four. 55 B2C4R10T2 B1C1R5T2 B2C5R18T2 55 54 B2C4R10T1 B1C1R5T1 B2C5R18T1 54 53 B2C3R13T2 B1C3R6T2 B2C3R18T2 53 52 B2C3R13T1 B1C3R6T1 B2C3R18T1 52 KEY 51 B2C4R9T2 B1C5R4T2 B2C5R17T2 51 50 B2C4R9T1 B1C5R4T1 B2C5R17T1 50 code definition 49 B2C2R11T2 B1C3R5T2 B2C1R17T2 49 B1 Liberty interstock/M.26 48 B2C2R11T1 B1C3R5T1 B2C1R17T1 48 B2 Mac interstock/M.26 47 B2C3R12T2 B1C4R5T2 B2C2R17T2 47 C1 Ginger Gold 46 B2C3R12T1 B1C4R5T1 B2C2R17T1 46 C2 Honeycrisp 45 B2C5R12T2 B1C5R3T2 B2C1R16T2 45 C3 Liberty 44 B2C5R12T1 B1C5R3T1 B2C1R16T1 44 C4 Macoun 43 B2C3R11T2 B1C3R4T2 B2C2R16T2 43 C5 Zestar! 42 B2C3R11T1 B1C3R4T1 B2C2R16T1 42 R1 rep 1 41 B2C5R11T2 B1C1R4T2 B2C4R18T2 41 R2 rep 2 40 B2C5R11T1 B1C1R4T1 B2C4R18T1 40 R3 rep 3 39 B2C1R10T2 B1C2R5T2 B2C2R15T2 39 R4 rep 4 38 B2C1R10T1 B1C2R5T1 B2C2R15T1 38 R5 rep 5 37 B2C5R10T2 B1C4R4T2 B2C3R17T2 37 R6 rep 6 36 B2C5R10T1 B1C4R4T1 B2C3R17T1 36 R7 rep 7 35 B2C3R10T2 B1C2R4T2 B2C5R16T2 35 R8 rep 8 34 B2C3R10T1 B1C2R4T1 B2C5R16T1 34 R9 rep 9 33 B2C3R9T2 B1C5R2T2 B2C1R15T2 33 R10 rep 10 32 B2C3R9T1 B1C5R2T1 B2C1R15T1 32 R11 rep 11 31 B2C2R10T2 B1C3R3T2 B2C4R17T2 31 R12 rep 12 30 B2C2R10T1 B1C3R3T1 B2C4R17T1 30 R13 rep 13 29 B2C2R9T2 B1C1R3T2 B2C2R14T2 29 R14 rep 14 28 B2C2R9T1 B1C1R3T1 B2C2R14T1 28 R15 rep 15 27 B2C1R9T2 B1C4R3T2 B2C5R15T2 27 R16 rep 16 26 B2C1R9T1 B1C4R3T1 B2C5R15T1 26 R17 rep 17 25 B2C5R9T2 B1C1R2T2 B2C4R16T2 25 R18 rep 18 24 B2C5R9T1 B1C1R2T1 B2C4R16T1 24 R19 rep 19 23 B1C5R1T2 B2C1R14T2 B1C1R8T2 23 T1 North tree 22 B1C5R1T1 B2C1R14T1 B1C1R8T1 22 T2 South tree 21 B1C4R2T2 B2C3R16T2 B1C5R8T2 21 20 B1C4R2T1 B2C3R16T1 B1C5R8T1 20 strikeout =dead or regrafted in 2007 19 B1C4 extra B2C5R14T2 B1C1R7T2 19 grey = rep incomplete in 2007, extra tree, other 18 B1C2R3T2 B2C5R14T1 B1C1R7T1 18 17 B1C2R3T1 B2C5R13T2 B1C4R8T2 17 METHODS 16 Fuji? B2C5R13T1 B1C4R8T1 16 Reps start in row 1 and continue through row 3 15 B1C3 extra B2C2R13T2 B1C5R7T2 15 Reps 1-8 are grafted onto Liberty trees 14 Fuji? B2C2R13T1 B1C5R7T1 14 Reps 9-19 are grafted onto McIntosh trees 13 B1C3 extra B2C4R15T2 B1C2R8T2 13 Liberty trees are in position 1-23 in rows 1 and 3, and position 24- 12 B1C4R1T2 B2C4R15T1 B1C2R8T1 12 71 in row 2. 11 B1C4R1T1 B2C3R15T2 B1C2R7T2 11 McIntosh trees are in position 24-71 in rows 1 and 3, and 1-23 in 10 B1C3R2T2 B2C3R15T1 B1C2R7T1 10 row 2. 9 B1C3R2T1 B2C4R14T2 Fuji? 9 All rep counting goes from North to South in each row 8 B1C2R2T2 B2C4R14T1 B1C3 extra 8 Tree code verified on 5/15/06 by Sarah Kingsley-Richards 7 B1C2R2T1 B2C1R13T2 Fuji? 7 6 B1C1R1T2 B2C1R13T1 B1C3R8T2 6 5 B1C1R1T1 B2C4R13T2 B1C3R8T1 5 4 B1C3R1T2 B2C4R13T1 B1C5R6T2 4 3 B1C3R1T1 (skip) B1C5R6T1 3 2 B1C2R1T2 B2C4R12T2 B1C4R7T2 2 1 B1C2R1T1 B2C4R12T1 B1C4R7T1 1 B2C3 extra B2C3 extra B2C3 extra ROW 1 ROW 2 ROW 3 NORTH

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Aerial Photo of OrganicA Orchards University of Vermont Horticulture Research & Education Center 65 Green Mountain Dr, South Burlington, VT Photo: 5/19/2012, Google Earth

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APPENDIX 3: FERTILIZER TABLE

Nutrient inputs appied to Orchards 1 and 2, 2006-2013. Orchard 1 Total annual amount of fertility inputs applied per hectare Material source unit 2006 2007 2008 2009 2010 2011 2012 2013 Chilean nitrate az kg - - 136 - - - - - Pro-Gro 5-3-4 a kg - - 1085 678 678 787 678 - Pro-Gro 6-0-6 a kg ------326 Sul-po-mag a kg ------629 -

materials 3

Soil-applied Compost b m 185 ------Wood chip mulch c,d m3 - - - 293 - 293 293 - Biomin Ca e l - 4.87 29.43 9.05 - - - - Biomin Mg e l - - 6.79 20.37 - - - - Biomin Mn e l - - 2.26 9.05 - - - - Biomin Zn e l - 2.43 6.80 6.79 3.40 6.79 2.26 - Mora Leaf Ca f kg - - - 23.87 18.44 6.51 16.27 29.29 NAK Fish g l - - - 18.11 18.11 9.05 - - Organic Gem fish h l ------54.33 36.22 Solubor i kg - 1.17 - 1.08 1.08 2.03 2.17 2.17

Foliar-applied materials Cal Mag DL j l 13.58 4.53

Orchard 2 Material 2006 2007 2008 2009 2010 2011 2012 2013 Chilean nitrate az kg ------Pro-Gro 5-3-4 a kg - - - 1302 949 949 1101 - Pro-Gro 6-0-6 a kg ------610 Sul-po-mag a kg ------1101 -

materials 3

Soil-applied Compost b m ------Wood chip mulch c,d m3 ------Biomin Ca e l - 21.50 55.18 50.93 4.53 - - - Biomin Mg e l - - 12.73 20.37 - - - - Biomin Mn e l - - 4.24 16.98 4.24 - - - Biomin Zn e l - 4.30 12.73 8.49 19.10 6.79 3.96 - Mora Leaf Ca f kg - - - 50.86 32.55 7.59 48.82 73.24 NAK Fish g l - - - 33.95 33.95 9.05 - - Organic Gem fish h l ------95.07 67.91 Solubor i kg - 2.06 - 2.03 2.03 2.17 3.80 4.07

Foliar-applied materials

z Material sources: a = North Country Organics, Brafdord, VT; b = Intervale Compost Company, Burlington, VT; c = on-site materials from tree clearing; d = Barrett's Tree Service, Burlington, VT; e = J.H. Biotech, Ventura, CA; f = Wilbur Ellis Co., San Francisco, CA; g = North American Kelp, Waldoboro, ME; h = Advanced Marine Technologies, New Bedford, MA; i = U.S. Borax, Inc., Valencia, CA; j = AgroK Unltd, Ukiah, CA.

196

APPENDIX 4: FOLIAR TISSUE ANALYSES

1.67

2.36

1.86

1.60

1.67

1.05

1.12

0.79

0.97

0.86

1.44

1.51

1.55

1.57

1.20

1.49

1.70

2.00

1.49

1.42

2.20

2.21

2.43

2.11

1.61

1.20

1.18

1.21

1.21

1.18

Fe/Mn

0.5 - 2.0

3

7

7

4

4

8

8

44

33

37

71

16

13

11

18

79

84

74

72

85

73

93

93

94

96

110

152

111

214

166

120

143

114

133

134

106

129

156

172

100

P/Zn

50 - 100

N/P

0.97

1.00

1.42

1.17

0.92

1.60

1.49

1.56

1.64

1.12

1.61

1.39

1.47

1.67

1.20

1.43

1.41

1.53

1.53

1.10

1.32

1.19

1.25

1.14

1.16

1.26

1.42

1.68

1.52

1.49

1.06

1.08

1.01

0.99

0.85

1.58

1.58

1.59

1.60

1.61

1.25 - 1.50

-

377

554

571

612

362

419

571

514

668

489

302

524

432

576

410

409

412

420

408

398

Al (ppm) Al

30

27

27

21

32

30

21

28

30

32

37.3

44.7

40.1

20.4

53.3

27.8

25.9

43.1

38.1

25.9

25.0

27.4

37.2

33.7

24.7

20.0

15.0

18.0

14.0

20.0

26.0

14.0

16.0

30.0

18.0

18.1

19.5

19.4

19.3

19.3

25 - 50

Zn (ppm)

66

62

46

25

88

30

30

27

36

32

41

37

32

55

50

41

39

28

44

49

40

41

41

41

42

35.7

28.8

34.3

51.8

41.1

65.7

61.4

74.2

83.5

69.8

44.4

44.6

35.7

47.2

52.3

35 - 100

Mn (ppm)

83

61

63

64

82

71

90

86

68

93

79

48

48

49

50

49

59.7

67.9

63.7

68.5

69.2

68.7

58.4

80.7

60.3

63.9

67.5

55.3

74.1

62.6

30 - 150

Fe (ppm)

6.2

6.9

7.3

7.4

7.7

6.5

6.5

4.9

4.7

4.5

6.8

2.6

2.6

2.9

4.3

3.2

6.9

6.4

5.0

5.5

8.3

7.9

7.9

7.8

7.8

7.8

4.14

5.76

4.97

3.46

7-12

Cu (ppm)

6

8

39

13

21

47

45

50

55

60

20.1

16.9

17.5

22.7

19.8

20.9

20.2

22.6

23.8

21.6

25.8

19.3

30.7

29.7

25.4

24.0

19.0

22.0

24.0

20.0

27.0

23.0

27.0

29.0

27.0

27.4

27.4

27.6

27.7

27.8

35-50

B (ppm)

0.33

0.41

0.30

0.45

0.53

0.36

0.30

0.32

0.40

0.43

0.16

0.15

0.15

0.14

0.16

0.20

0.17

0.18

0.17

0.20

0.40

0.35

0.31

0.36

0.44

0.16

0.13

0.13

0.15

0.14

0.22

0.18

0.25

0.22

0.31

0.18

0.18

0.18

0.18

0.19

P (%)

0.1 - 0.2

0.21

0.21

0.18

0.24

0.28

0.22

0.22

0.21

0.25

0.24

0.24

0.21

0.21

0.27

0.27

0.23

0.21

0.19

0.27

0.24

0.21

0.22

0.18

0.26

0.25

0.20

0.20

0.17

0.30

0.29

0.20

0.21

0.20

0.29

0.28

0.26

0.26

0.26

0.26

0.26

Mg (%) Mg

0.35 - 0.50

2.3

2.01

1.66

1.94

2.27

1.57

1.51

1.54

1.64

1.94

1.75

1.83

1.68

1.64

2.01

1.98

1.80

1.82

1.74

2.19

1.90

1.82

1.76

1.91

2.01

1.64

1.38

1.32

1.43

1.42

1.97

1.80

1.80

1.87

2.13

1.43

1.43

1.42

1.42

1.42

K (%)

1.3-1.8

0.85

0.79

0.75

0.71

1.07

0.92

0.76

0.83

0.79

0.92

0.94

0.70

0.87

0.71

1.02

1.09

1.03

1.14

0.91

1.30

1.16

0.97

1.05

0.92

1.47

1.29

0.94

1.25

1.09

1.41

1.56

1.00

1.04

1.01

1.43

1.69

1.69

1.67

1.70

1.73

Ca (%)

1.3 - 2.0

z

2.4

2.23

2.02

2.35

2.27

2.09

2.51

2.25

2.69

2.18

2.82

2.54

2.47

2.74

2.41

2.82

2.54

2.78

2.65

2.40

2.51

2.17

2.20

2.17

2.33

2.06

1.96

2.22

2.18

2.11

2.09

1.94

1.81

1.86

1.82

2.25

2.25

2.26

2.28

2.29

N (%)

1.9-2.1

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Cultivar

y

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Orchard

Plant tissue mineral nutrient level recommendations from UMaine Testing Lab. Testing from recommendations UMaine level nutrient mineral Plant tissue

Leaves collected annually in midsummer. 50 +/- leaves per sample collected from all trees in sample unit.Leaves were washed and submitted to UVM Ag Testing Lab (2006-2007, Burlington, Lab (2006-2007,Testing were unit.Leaves Burlington, washed sample trees Ag to and in UVM submitted from all 50 midsummer. collected per +/- in leaves sample annually Leaves collected

y

VT) or UMaine Testing Lab VT) (2008-2011,Testing or UMaine Orono, ME) for analysis.

z

2006

2006

2006

2006

2006

2007

2007

2007

2007

2007

2008

2008

2008

2008

2008

2009

2009

2009

2009

2009

2010

2010

2010

2010

2010

2011

2011

2011

2011

2011

2012

2012

2012

2012

2012

2013

2013

2013

2013

2013

Year Recommended level 2006-2013 Orchard 1 Foliar 2006-2013 Tissue Analysis Orchard 1 Foliar

197

2.05

2.22

2.16

2.23

1.61

1.09

1.13

0.85

0.75

0.92

1.69

1.98

2.82

2.16

1.85

1.51

2.40

2.48

2.27

1.63

1.87

2.60

4.79

2.81

2.40

0.98

1.34

2.01

1.26

1.13

Fe/Mn

0.5 - 2.0

9

8

8

5

91

51

67

12

12

12

10

10

15

91

85

88

142

142

162

175

143

148

150

128

153

136

100

100

110

113

101

131

111

140

116

121

125

107

121

155

115

100

106

132

116

P/Zn

50 - 100

N/P

1.43

1.15

1.44

1.33

1.21

1.42

1.20

1.41

1.33

1.17

1.97

1.68

2.10

1.76

1.56

1.66

1.50

1.53

1.52

1.34

1.36

1.04

1.40

1.41

1.31

1.64

1.17

1.39

1.39

1.34

1.76

1.50

1.63

1.44

1.62

1.31

1.11

1.48

1.49

1.27

1.51

1.72

1.40

1.37

1.58

1.25 - 1.50

-

157

181

201

375

187

310

319

537

279

198

284

296

429

253

207

315

354

339

181

187.5

Al (ppm) Al

9

12

12

13

12

14

12

16

17

12.5

17.5

10.5

13.5

25.5

22.5

14.3

12.9

14.3

24.7

38.8

19.9

14.1

16.1

13.4

13.0

14.0

14.0

12.0

13.0

14.0

12.0

14.0

14.0

11.0

14.4

13.2

13.5

14.3

14.7

13.05

25.55

23.55

14.45

18.05

10.795

25 - 50

Zn (ppm)

29

30

29

25

32

26

26

25

27

19

21

35

25

25

30

38

31

25

14

26

30

40

32

17

29

25.5

18.5

24.5

23.5

29.8

28.9

27.5

89.9

31.6

31.1

37.3

24.95

35.25

63.85

61.15

63.35

68.25

34.15

20.65

33.65

35 - 100

Mn (ppm)

53

60

62

68

62

58

65

67

73

72

40

43

34

37

42

53.9

69.1

69.4

54.3

63.3

66.7

60.85

60.75

60.25

56.25

67.85

57.45

61.85

58.15

62.35

30 - 150

Fe (ppm)

6.2

4.5

4.3

4.3

4.8

4.4

9.4

7.7

9.7

8.2

8.2

7.5

8.0

7.2

7.9

7.9

10.9

8.64

8.76

6.86

6.12

7-12

4.735

4.495

4.095

4.165

4.465

11.25

6.745

6.915

10.115

Cu (ppm)

16

15

23

17

17

18

18

22

54

58

52

25

26

27

18.5

18.5

46.5

47.5

26.7

23.3

25.2

24.8

22.4

27.7

27.0

22.0

26.0

28.0

24.0

33.0

26.0

29.0

27.0

30.0

28.8

23.5

28.1

26.6

25.4

24.75

23.05

20.55

26.85

28.95

27.55

35-50

B (ppm)

0.17

0.17

0.21

0.21

0.20

0.19

0.18

0.21

0.24

0.23

0.11

0.12

0.11

0.09

0.12

0.15

0.15

0.13

0.14

0.16

0.23

0.22

0.18

0.19

0.23

0.17

0.17

0.17

0.18

0.20

0.12

0.12

0.12

0.17

0.15

0.17

0.15

0.15

0.17

0.17

0.17

0.13

0.14

0.19

0.17

P (%)

0.1 - 0.2

0.39

0.30

0.50

0.31

0.40

0.37

0.31

0.48

0.31

0.36

0.28

0.24

0.29

0.26

0.32

0.35

0.31

0.32

0.28

0.37

0.34

0.31

0.32

0.30

0.37

0.34

0.31

0.30

0.33

0.38

0.31

0.29

0.29

0.32

0.35

0.35

0.31

0.30

0.37

0.41

0.31

0.31

0.26

0.27

0.36

Mg (%) Mg

0.35 - 0.50

1.9

1.9

1.68

1.89

1.85

1.83

2.04

2.09

1.52

1.48

1.67

1.51

1.42

1.75

1.77

1.62

1.87

1.17

1.30

1.29

1.47

1.27

1.66

1.76

1.56

1.42

1.80

1.42

1.17

1.49

1.46

1.43

1.795

1.905

1.865

1.405

1.425

1.465

1.435

1.865

2.115

1.505

1.915

1.785

1.725

K (%)

1.3-1.8

1.3

0.88

0.71

1.24

0.77

1.00

0.88

0.78

1.19

0.76

0.90

0.80

0.65

0.81

0.66

0.95

0.82

0.73

0.76

0.74

0.98

1.31

1.28

1.23

1.19

1.46

1.27

1.43

1.23

1.41

1.20

1.46

1.16

0.97

1.34

1.25

1.45

1.51

1.41

1.20

1.59

1.045

0.985

1.025

0.885

Ca (%)

1.3 - 2.0

z

2.4

2.2

2.4

2.18

2.67

2.44

2.46

2.55

2.29

2.44

2.55

2.99

2.61

2.26

2.15

2.06

1.95

2.10

2.11

2.06

2.18

1.95

2.31

2.12

2.28

2.14

2.01

2.08

2.00

2.26

2.685

2.485

2.765

2.605

2.425

2.175

2.345

2.535

2.465

2.255

2.475

2.465

2.245

2.485

2.495

N (%)

1.9-2.1

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Zestar!

Macoun

Liberty

Honeycrisp

Ginger Gold Ginger

Cultivar

y

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

Orchard

Plant tissue mineral nutrient level recommendations from UMaine Testing Lab. Testing from recommendations UMaine level nutrient mineral Plant tissue

Leaves collected annually in midsummer. 50 +/- leaves per sample collected from all trees in sample unit.Leaves were washed and submitted to UVM Ag Testing Lab (2006-2007, Burlington, Lab (2006-2007,Testing were unit.Leaves Burlington, washed sample trees Ag to and in UVM submitted from all 50 midsummer. collected per +/- in leaves sample annually Leaves collected

y

VT) or UMaine Testing Lab VT) (2008-2011,Testing or UMaine Orono, ME) for analysis.

z

2006

2006

2006

2006

2006

2006

2006

2006

2006

2006

2007

2007

2007

2007

2007

2008

2008

2008

2008

2008

2009

2009

2009

2009

2009

2010

2010

2010

2010

2010

2011

2011

2011

2011

2011

2012

2012

2012

2012

2012

2013

2013

2013

2013

2013

Year Recommended level 2006-2013 Orchard 2 Foliar 2006-2013 Tissue Analysis Orchard 2 Foliar

198

APPENDIX 5: ORGANIC PESTICIDE TREATMENTS IN ORCHARDS 1&2

w

w

w

-

-

-

-

2

1

6

3

7

3

1

1/2

1/3

2013

10/7

-

-

-

-

1

6

2

8

6

1

1

1

0

12

2012

-

-

-

-

-

3

4

9

9

1

1

6

6

12

2011

w

w

-

-

-

-

1

3

5

2

1

1

6

7

1/2

1/2

2010

w

x

-

-

-

-

-

-

2

3

5

1

1

4

3

8/9

2009

-

-

-

-

-

-

1

6

1

8

1

3

8

5

2008

Total number of applications per applications season of number Total

w

w

w

x

-

-

-

-

-

1

1

1

7

5

2

1/2

2/7

1/2

2007

w

w

x

x

x

x

-

-

-

-

-

-

-

2

1

1

1

1

2/6

2006

3/12

y

kg

l

kg

g

ml

kg

l

l

l

kg

kg

kg

l

kg

73

6.1

2.3

0.4-2.3

1.1-1.7

Rate per acreRate

4.5-18.1

4.5-18.1

5.7-13.0

2.3-19.5

1.08-2.17

23.7-71.0

20.3-54.3

4.34-4.67

10.9-17.5

z

l

k

j

i

e

h

g

f

e

c

d

c

b

a

Mfr

C. subtsugaeC.

parafinnic oil parafinnic

B. thuringiensisB.

spinosad

granulosis virus granulosis

kaolin clay kaolin

azadiractin

pyrethrum

neem oil neem

streptomycin

B. subtilisB.

copper hydroxide

calcium polysulfide calcium

sulfur

Active ingredient Active

x

Grandevo

JMS Stylet Oil Stylet JMS

Dipel DF

Entrust

CYD-X

Surround

Aza-Direct 1.2L Aza-Direct

Pyganic

Trilogy

Agri-Mycin 17 Agri-Mycin

Serenade Max Serenade

Champ WG Champ

Lime sulfur Lime

Microthiol Disperss Microthiol Material

bactericides

Insecticides

Fungicides & & Fungicides

The first value represents the number of applications made to Orchard 1, and the second value applications made to Orchard 2. Orchard to made applications value second the and 1, Orchard to made applications of number the represents value first The

Reduced rates of sulfur (0.68-4.07 kg/ha) were applied in Orchard 1 in 2006 werein 1 applied Orchard (0.68-4.07 in kg/ha) sulfur rates of Reduced

Product manufacturers: a = United Phosphorous Inc., King of Prussia, PA; b = Miller Chemical & Fertilizer Corp., Hanover, PA; & ProductInc., c Fertilizer a = Phosphorous Nufarm = Americas, manufacturers: United Burr Chemical of Ridge, Inc.,Prussia, PA; King b = Miller

Applied to Orchard 2 only. 2 Orchard Applied to

w

x

y

FL; l = Marrone Bio Innovations Inc., = Innovations FL; Marrone l CA. Bio Davis,

Tessenderlo Kerley, Inc., Phoenix, AZ; i = Dow Agrosciences LLC, Indianapolis, IN; j = Valent USA Corp., USA Creek, k IN; Walnut = Farms,j CA; JMS = Flower Valent Inc.,LLC, Beach, Indianapolis, Vero Tessenderlo Inc.,= Kerley, Dow i Agrosciences AZ; Phoenix,

IL; d = AgraQuest, Inc., Davis, CA; e = Certis USA, LLC, Columbia, MO; f = McLaughlin Gormley King Co., Minneapolis, MN; g = MN; Gowan g Co.,Co., Yuma,h Minneapolis, King = AZ; Gormley Inc.,IL; MO; d LLC,e f USA, = = = AgraQuest, CA; Davis, Certis McLaughlin Columbia,

z Orchard 1 Orchard Pesticide applications in OrganicA Orchards 1 and 2, 2006-2013. 2, 1 and Orchards OrganicA Pesticide in applications

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APPENDIX 6: WEEKLY CODLING MOTH TRAP CAPTURES, 2008-2013

Year Week 2008 2009 2010 2011 2012 2013 1 0.0 1.3 0.0 0.0 0.0 0.0 2 0.0 0.7 0.0 0.0 1.0 0.5 3 0.7 2.0 1.7 1.7 7.0 2.3 4 2.5 2.3 4.7 10.7 10.5 0.5 5 4.7 2.0 10.0 19.3 7.5 1.5 6 4.0 6.0 4.0 16.0 11.3 1.5 7 21.0 6.0 2.3 12.3 16.8 1.3 8 16.0 4.0 2.7 11.7 20.0 0.3 9 5.3 7.3 5.0 17.3 12.3 0.0 10 2.7 1.0 2.7 16.7 3.0 0.8 11 4.0 2.7 2.7 9.7 1.3 0.0 12 3.3 4.7 8.3 12.3 4.3 0.5 13 9.0 0.7 13.7 12.7 16.3 0.3 14 na na 22.0 14.0 6.5 0.0 15 na na 27.0 6.3 4.3 na 16 na na 4.3 2.3 2.0 na 17 na na 4.7 na na na zValues represent average new captures of codling moth adults in two pheromone-baited (Scentry L104, Scentry Biologicals Inc., Billings, MT) wing traps per orchard in Orchards 1 & 2. yTrapping commenced at bloom in each season, so weeks do not coincide with specific dates in each season. Trapping continued until the beginning of harvest.

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APPENDIX 7: FIGURES OF BIOTIC (DISEASE AND INSECT PEST) AND ABIOTIC DAMAGE ON FRUIT

Apple scab on ‘Macoun’, not sufficient to Apple scab on ‘Zestar!’ sufficient to reduce downgrade fruit grade fruit grade to Utility.

Rust on calyx end of ‘Liberty’ Lenticel spotting (left) and Brooks spot (right) on ‘Ginger Gold’.

Rot on ‘Zestar!’ Rot on ‘Honeycrisp’

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Corked-over plum curculios ovipositional Severe fruit corking from plum curculio on stings sufficient to downgrade fruit to Utility ‘Honeycrisp’. grade.

European apple sawfly damage at harvest. Abscising fruit with European apple sawfly damage.

Internal lepidopteran damage on Codling moth (internal lepidopteran) larvae ‘Honeycrisp’. in ‘Macoun’.

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Apple maggot trail in ‘Honeycrisp’. Surface lepidopteran damage on ‘Macoun’.

Sunburn on ‘Zestar!’. Spray burn on ‘Ginger Gold’.

Bitter pit on ‘Honeycrisp’. Frost ring on ‘Honeycrisp’

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APPENDIX 8: USDA APPLE GRADING STANDARDS United States Standards for Grades of Apples

Effective December 19, 2002

Compiled from: http://www.ams.usda.gov/AMSv1.0/getfile?dDocName=STELPRDC5050339

Grades

§51.300 U.S. Extra Fancy.

“U.S. Extra Fancy” consists of apples of one variety (except when more than one variety is printed on the container) which are mature but not overripe, clean, fairly well formed, free from decay, internal browning, internal breakdown, soft scald, scab, freezing injury, visible water core, and broken skins. The apples are also free from injury caused by bruises, brown surface discoloration, smooth net-like russeting, sunburn or sprayburn, limb rubs, hail, drought spots, scars, disease, insects, or other means. The apples are free from damage caused by bitter pit or spot and by smooth solid, slightly rough or rough russeting, or stem or calyx cracks, as well as damage by invisible water core after January 31st of the year following the year of production except for the Fuji variety of apples. Invisible water core shall not be scored against the Fuji variety of apples under any circumstances. For the apple varieties listed in Table I of §51.305, each apple of this grade has the amount of color specified for the variety. (See §§51.305 and 51.306.)

§51.301 U.S. Fancy.

“U.S. Fancy” consists of apples of one variety (except when more than one variety is printed on the container) which are mature but not overripe, clean, fairly well formed, and free from decay, internal browning, internal breakdown, soft scald, freezing injury, visible water core, and broken skins. The apples are also free from damage caused by bruises, brown surface discoloration, russeting, sunburn or sprayburn, limb rubs, hail, drought spots, scars, stem or calyx cracks, disease, insects, bitter pit, Jonathan spot, or damage by other means, or invisible water core after January 31st of the year following the year of production, except for the Fuji variety of apples. Invisible water core shall not be scored against the Fuji variety of apples under any circumstances. For the apple varieties listed in Table I of §51.305, each apple of this grade has the amount of color specified for the variety. (See §§51.305 and 51.306.)

§51.302 U.S. No. 1.

“U.S. No. 1” consists of apples which meet the requirements of U.S. Fancy grade except for color, russeting, and invisible water core. In this grade, less color is required for all

204 varieties listed in Table I of §51.305. Apples of this grade are free from excessive damage caused by russeting which means that apples meet the russeting requirements for U.S. Fancy as defined under the definitions of “damage by russeting,” except the aggregate area of an apple which may be covered by smooth net-like russeting shall not exceed 25 percent; and the aggregate area of an apple which may be covered by smooth solid russeting shall not exceed 10 percent: Provided, That, in the case of the Yellow Newtown or similar varieties, the aggregate area of an apple which may be covered with smooth solid russeting shall not exceed 20 percent. Each apple of this grade has the amount of color specified in §51.305 for the variety. Invisible water core shall not be scored in this grade. (See §§51.305 and 51.306.)

§51.303 U.S. Utility.

“U.S. Utility” consists of apples of one variety (except when more than one variety is printed on the container) which are mature but not overripe, not seriously deformed and free from decay, internal browning, internal breakdown, soft scald, and freezing injury. The apples are also free from serious damage caused by dirt or other foreign matter, broken skins, bruises, brown surface discoloration, russeting, sunburn or sprayburn, limb rubs, hail, drought spots, scars, stem or calyx cracks, visible water core, bitter pit or Jonathan spot, disease, insects, or other means. (See §51.306.)

§51.304 Combination grades.

(a) Combinations of the above grades may be used as follows:

(1) Combination U.S. Extra Fancy and U.S. Fancy;

(2) Combination U.S. Fancy and U.S. No. 1; and

(3) Combination U.S. No. 1 and U.S. Utility.

(b) Combinations other than these are not permitted in connection with the U.S. apple grades. When Combination grades are packed, at least 50 percent of the apples in any lot shall meet the requirements of the higher grade in the combination. (See §51.306.)

§51.305 Color requirements.

In addition to the requirements specified for the grades set forth in §§51.300 to 51.304, apples of these grades shall have the percentage of color specified for the variety in Table I appearing in this Section (not included in this Appendix because no varieties in the study orchard were included in the table). All apple varieties other than those appearing in Table I shall have no color requirements pertaining to these grades. For the solid red varieties, the percentage stated refers to the area of the surface which must be covered with a good shade of solid red characteristic of the variety: Provided, That an apple

205 having color of a lighter shade of solid red or striped red than that considered as a good shade of red characteristic of the variety may be admitted to a grade, provided it has sufficient additional area covered so that the apple has as good an appearance as one with the minimum percentage of good red characteristic of the variety required for the grade. For the striped red varieties, the percentage stated refers to the area of the surface in which the stripes of a good shade of red characteristic of the variety shall predominate over stripes of lighter red, green, or yellow. However, an apple having color of a lighter shade than that considered as a good shade of red characteristic of the variety may be admitted to a grade, provided it has sufficient additional area covered so that the apple has as good an appearance as one with the minimum percentage of stripes of a good red characteristic of the variety required for the grade. Faded brown stripes shall not be considered as color.

(A) Color standards USDA Visual Aid APL-CC-1 (Plates a - e) consists of a folder containing the color requirements for apples set forth in this section and five plates illustrating minimum good shade of solid red or striped red color, minimum compensating color and shade not considered color, for the following 12 varieties: Red Delicious, Red Rome, Empire, , , Jonathan, , McIntosh, Cortland, Rome Beauty, Delicious, and York.

These color standards will be available for examination and purchasing information in the Fresh Products Branch, Fruit and Vegetable Programs, AMS, U.S. Department of Agriculture, South Building, Washington, D.C. 20250; in any field office of the Fresh Products Branch; or upon request of any authorized inspector of the Fresh Fruit and Vegetable Inspection Service.

§51.306 Tolerances.

In order to allow for variations incident to proper grading and handling in each of the grades in 51.300, 51.301, 51.302, 51.303, and 51.304 the following tolerances are provided as specified:

(a) Defects:

(1) U.S. Extra Fancy, U.S. Fancy, U.S. No. 1, and U.S. No. 1 Hail grades: 10 percent of the apples in any lot may fail to meet the requirements of the grade, but not more than one-half of this amount, or 5 percent, shall be allowed for apples which are seriously damaged, including therein not more than 1 percent for apples affected by decay or internal breakdown.

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(2) U.S. Utility grade: 10 percent of the apples in any lot may fail to meet the requirements of the grade, but not more than one-half of this amount, or 5 percent, shall be allowed for apples which are seriously damaged by insects, and including in the total tolerance not more than 1 percent for apples affected by decay or internal breakdown.

(b) When applying the foregoing tolerances to Combination grades, no part of any tolerance shall be allowed to reduce, for the lot as a whole, the 50 percent of apples of the higher grade required in the combination, but individual containers shall have not less than 40 percent of the higher grade.

(c) Size: When size is designated by the numerical count for a container, not more than 10 percent of packages in the lot may fail to be fairly uniform. When size is designated by minimum or maximum diameter, not more than 5 percent of the apples in any lot may be smaller than the designated minimum, and not more than 10 percent may be larger than the designated maximum. “Fairly uniform” means the size of the fruit within the container does not vary more than ½ inch diameter from the smallest to largest fruit.

Definitions

§51.312 Mature.

“Mature” means that the apples have reached the stage of development which will insure the proper completion of the ripening process. Before a mature apple becomes overripe it will show varying degrees of firmness, depending upon the stage of the ripening process. The following terms are used for describing different stages of firmness of apples:

(a) “Hard” means apples with a tenacious flesh and starchy flavor.

(b) “Firm” means apples with a tenacious flesh but which are becoming crisp with a slightly starchy flavor, except the Delicious variety.

(c) “Firm ripe” means apples with crisp flesh except that the flesh of the Gano, , and Rome Beauty varieties may be slightly mealy.

(d) “Ripe” means apples with mealy flesh and soon to become soft for the variety.

§51.313 Overripe.

“Overripe” means apples which have progressed beyond the stage of ripe, with flesh very mealy or soft, and past commercial utility.

§51.314 Clean.

“Clean” means that the apples are free from excessive dirt, dust, spray residue, and other foreign material.

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§51.315 Fairly well formed.

“Fairly well formed” means that the apple may be slightly abnormal in shape but not to an extent which detracts materially from its appearance.

§51.316 Injury.

“Injury” means any specific defect defined in this Section or an equally objectionable variation of any one of these defects, any other defect, or any combination of defects, which more than slightly detract from the appearance or the edible or shipping quality of the apple. In addition, specific defect measurements are based on an apple three inches in diameter. Corresponding smaller or larger areas would be allowed on smaller or larger fruit. Any reference to “inch” or “inches in diameter” refers to that of a circle of the specified diameter. Any reference to “aggregate area,” “total area,” or “aggregate affected area” means the gathering together of separate areas into one mass for the purpose of comparison to determine the extent affected. The following specific defects shall be considered as injury:

(a) Russeting in the stem cavity or calyx basin which cannot be seen when the apple is placed stem end or calyx end down on a flat surface shall not be considered in determining whether an apple is injured by russeting. Smooth net-like russeting outside of the stem cavity or calyx basin shall be considered as injury when an aggregate area of more than 10 percent of the surface is covered, and the color of the russeting shows no very pronounced contrast with the background color of the apple, or lesser amounts of more conspicuous net-like russeting when the appearance is affected to a greater extent than the amount permitted above.

(b) Sunburn or sprayburn, when the discolored area does not blend into the normal color of the fruit.

(c) Dark brown or black limb rubs which affect a total area of more than one-fourth inch in diameter, except that light brown limb rubs of a russet character shall be considered under the definition of injury by russeting.

(d) Hail marks, drought spots, other similar depressions or scars:

(1) When the skin is broken, whether healed or unhealed;

(2) When there is appreciable discoloration of the surface;

(3) When any surface indentation exceeds one-sixteenth inch in depth;

(4) When any surface indentation exceeds one-eighth inch in diameter; or

(5) When the aggregate affected area of such spots exceeds one-half inch in diameter.

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(e) Bruises which are not slight and incident to proper handling and packing, and which are greater than:

(1) 1/8 inch in depth;

(2) 5/8 inch in diameter;

(3) any combination of lesser bruises which detract from the appearance or edible quality of the apple to an extent greater than any one bruise described in paragraphs (1) or (2) of this section.

(f) Brown surface discoloration when caused by delayed sunburn, surface scald, or any other means and affects an area greater than 1/4 inch in diameter.

(g) Disease:

(1) Cedar rust infection which affects a total area of more than three-sixteenths inch in diameter.

(2) Sooty blotch or fly speck which is thinly scattered over more than 5 percent of the surface, or dark, heavily concentrated spots which affect an area of more than one-fourth inch in diameter.

(3) Red skin spots which are thinly scattered over more than one-tenth of the surface, or dark, heavily concentrated spots which affect an area of more than one-fourth inch in diameter.

(h) Insects:

(1) Any healed sting or healed stings which affect a total area of more than one-eighth inch in diameter including any encircling discolored rings.

(2) Worm holes.

§51.317 Damage.

“Damage” means any specific defect defined in this section or an equally objectionable variation of any one of these defects, any other defect, or any combination of defects, which materially detract from the appearance, or the edible or shipping quality of the apple. In addition, specific defect measurements are based on an apple three inches in diameter. Corresponding smaller or larger areas would be allowed on smaller or larger fruit. Any reference to “inch” or “inches in diameter” refers to that of a circle of the specified diameter. Any reference to “aggregate area,” “total area,” or “aggregate affected area” means the gathering together of separate areas into one mass for the

209 purpose of comparison to determine the extent affected. The following specific defects shall be considered as damage:

(a) Russeting in the stem cavity or calyx basin which cannot be seen when the apple is placed stem end or calyx end down on a flat surface shall not be considered in determining whether an apple is damaged by russeting, except that excessively rough or bark-like russeting in the stem cavity or calyx basin shall be considered as damage when the appearance of the apple is materially affected. The following types and amounts of russeting outside of the stem cavity or calyx basin shall be considered as damage:

(1) Russeting which is excessively rough on and other similar varieties.

(2) Smooth net-like russeting, when an aggregate area of more than 15 percent of the surface is covered, and the color of the russeting shows no very pronounced contrast with the background color of the apple, or lesser amounts of more conspicuous net-like russeting when the appearance is affected to a greater extent than the amount permitted above.

(3) Smooth solid russeting, when an aggregate area of more than 5 percent of the surface is covered, and the pattern and color of the russeting shows no very pronounced contrast with the background color of the apple, or lesser amounts of more conspicuous solid russeting when the appearance is affected to a greater extent than the above amount permitted.

(4) Slightly rough russeting which covers an aggregate area of more than one-half inch in diameter.

(5) Rough russeting which covers an aggregate area of more than one-fourth inch in diameter.

(b) Sunburn or sprayburn which has caused blistering or cracking of the skin, or when the discolored area does not blend into the normal color of the fruit unless the injury can be classed as russeting.

(c) Limb rubs which affect a total area of more than one-half inch in diameter, except that light brown limb rubs of a russet character shall be considered under the definition of damage by russeting.

(d) Hail marks, drought spots, other similar depressions, or scars:

(1) When any unhealed mark is present;

(2) When any surface indentation exceeds one-eighth inch in depth;

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(3) When the skin has not been broken and the aggregate affected area exceeds one-half inch in diameter; or

(4) When the skin has been broken and well healed, and the aggregate affected area exceeds one-fourth inch in diameter.

(e) Stem or calyx cracks which are not well healed, or well healed stem or calyx cracks which exceed an aggregate length of one-fourth inch.

(f) Invisible water core existing around the core and extending to water core in the vascular bundles, or surrounding the vascular bundles when the affected areas surrounding three or more vascular bundles meet or coalesce, or existing in more than a slight degree outside the circular area formed by the vascular bundles. Provided, That invisible water core shall not be scored as damage against the Fuji variety of apples under any circumstances.

(g) Bruises which are not slight and incident to proper handling and packing, and which are greater than:

(1) 3/16 inch in depth;

(2) 7/8 inch in diameter;

(3) any combination of lesser bruises which detract from the appearance or edible quality of the apple to an extent greater than any one bruise described in paragraphs (1) or (2) of this section.

(h) Brown surface discoloration when caused by delayed sunburn, surface scald, or any other means and affects an area greater than 1/2 inch in diameter.

(i) Disease:

(1) Scab spots which affect a total area of more than one-fourth inch in diameter.

(2) Cedar rust infection which affects a total area of more than one-fourth inch in diameter.

(3) Sooty blotch or fly speck which is thinly scattered over more than one-tenth of the surface, or dark, heavily concentrated spots which affect an area of more than one-half inch in diameter.

(4) Red skin spots which are thinly scattered over more than one-tenth of the surface, or dark, heavily concentrated spots which affect an area of more than one-half inch in diameter.

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(5) Bitter pit or Jonathan spot when one or more spots affects the surface of the apple.

(j) Insects:

(1) Any healed sting or healed stings which affect a total area of more than three- sixteenths inch in diameter including any encircling discolored rings.

(2) Worm holes.

§51.318 Serious damage.

“Serious damage” means any specific defect defined in this section; or an equally objectionable variation of any one of these defects, any other defect, or any combination of defects which seriously detract from the appearance, or the edible or shipping quality of the apple. In addition, specific defect measurements are based on an apple three inches in diameter. Corresponding smaller or larger areas would be allowed on smaller or larger fruit. Any reference to “inch” or “inches in diameter” refers to that of a circle of the specified diameter. Any reference to “aggregate area,” “total area,” or “aggregate affected area” means the gathering together of separate areas into one mass for the purpose of comparison to determine the extent affected. The following specific defects shall be considered as serious damage:

(a) The following types and amounts of russeting shall be considered as serious damage:

(1) Smooth solid russeting, when more than one-half of the surface in the aggregate is covered, including any russeting in the stem cavity or calyx basin, or slightly rough, or excessively rough or bark-like russeting, which detracts from the appearance of the fruit to a greater extent than the amount of smooth solid russeting permitted: Provided, That any amount of russeting shall be permitted on Roxbury Russet and other similar varieties.

(b) Sunburn or sprayburn which seriously detracts from the appearance of the fruit.

(c) Limb rubs which affect more than one-tenth of the surface in the aggregate.

(d) Hail marks, drought spots, or scars, if they materially deform or disfigure the fruit, or if such defects affect more than one-tenth of the surface in the aggregate: Provided, That no hail marks which are unhealed shall be permitted and not more than an aggregate area of one-half inch shall be allowed for well healed hail marks where the skin has been broken.

(e) Stem or calyx cracks which are not well healed, or well healed stem or calyx cracks which exceed an aggregate length of one-half inch.

(f) Visible water core which affects an area of more than one-half inch in diameter.

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(g) Disease:

(1) Scab spots which affect a total area of more than three-fourths inch in diameter.

(2) Cedar rust infection which affects a total area of more than three-fourths inch in diameter.

(3) Sooty blotch or fly speck which affects more than one-third of the surface.

(4) Red skin spots which affect more than one-third of the surface.

(5) Bitter pit or Jonathan spot which is thinly scattered over more than one-tenth of the surface.

(h) Insects:

(1) Healed stings which affect a total area of more than one-fourth inch in diameter including any encircling discolored rings.

(2) Worm holes.

(i) Bruises which are not slight and incident to proper handling and packing, and which are greater than:

(1) 3/8 inch in depth;

(2) 1 1/8 inches in diameter;

(3) any combination of lesser bruises which detract from the appearance or edible quality of the apple to an extent greater than any one bruise described in paragraph (i)(1) or (2) of this section.

(j) Brown surface discoloration when caused by delayed sunburn, surface scald, or any other means and affects an area greater than 3/4 inch in diameter.

§51.319 Seriously deformed.

“Seriously deformed” means that the apple is so badly misshapen that its appearance is seriously affected.

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APPENDIX 9: DETAILED, ACTUAL ANNUAL LABOR, EQUIPMENT, AND INPUT COSTS, $US/HA. Orchard 1

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Total Labor Orchard establishment Planting/preparation $ 1,032 $ 1,003 $ 1,075 $ 3,297 $ 14 $ - $ - $ - $ - $ - $ - $ 6,422 Grafting $ - $ - $ - $ 57 $ - $ - $ - $ - $ - $ - $ - $ 57 Trellis construction $ - $ - $ - $ 3,748 $ 50 $ - $ - $ - $ - $ - $ - $ 3,799 Tree training $ - $ - $ - $ 588 $ 143 $ 258 $ 308 $ 229 $ - $ - $ - $ 1,527 Groundcover management $ - Debris shredding $ - $ - $ - $ 143 $ - $ - $ 215 $ 143 $ 202 $ 237 $ 95 $ 1,035 Flame weeding $ - $ - $ - $ - $ 215 $ - $ - $ - $ - $ - $ 229 $ 444 Hand weeding $ - $ - $ - $ 1,663 $ 3,412 $ 889 $ 1,204 $ 6,049 $ 143 $ 315 $ 330 $ 14,004 Herbicide application $ - $ - $ - $ - $ - $ - $ - $ - $ - $ 229 $ - $ 229 Mechanical tillage $ - $ - $ - $ - $ - $ 860 $ 215 $ 143 $ 215 $ - $ - $ 1,433 Mowing $ - $ 430 $ 502 $ 545 $ 237 $ 394 $ 72 $ - $ 287 $ 143 $ 287 $ 2,895 Mulch application $ - $ - $ - $ 473 $ - $ - $ 401 $ - $ 344 $ 115 $ - $ 1,333 Orchard maintenance $ - Fertilizer application $ - $ - $ - $ - $ - $ 115 $ 86 $ 57 $ - $ 229 $ 47 $ 535 Irrigation maintenance $ - $ - $ - $ 975 $ - $ 172 $ 14 $ - $ - $ 57 $ 143 $ 1,362 Pollen application $ - $ - $ - $ - $ - $ 14 $ 57 $ 57 $ 29 $ 108 $ - $ 265 Pruning $ - $ - $ - $ - $ 36 $ 14 $ 29 $ 72 $ 72 $ 108 $ 143 $ 473 Spraying $ - $ - $ - $ 72 $ 645 $ 1,183 $ 1,541 $ 2,150 $ 753 $ 645 $ 609 $ 7,597 Vertebrate mangement $ - $ - $ - $ 287 $ 201 $ 172 $ 229 $ 100 $ 229 $ - $ - $ 1,218 Cropload management $ - $ - $ - $ - $ 143 $ - $ - $ - $ - $ - $ - $ 143 Total labor $ 1,032 $ 1,433 $ 1,577 $ 11,847 $ 5,096 $ 4,071 $ 4,372 $ 9,002 $ 2,273 $ 2,186 $ 1,883 $ 44,773 Labor % of total costs 36% 29% 25% 21% 63% 31% 34% 58% 18% 15% 24% 29% Equipment Orchard establishment Planting/preparation $ 1,835 $ 2,018 $ 1,290 $ 2,569 $ - $ - $ - $ - $ - $ - $ - $ 7,712 Grafting $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - Trellis construction $ - $ - $ - $ 903 $ - $ - $ - $ - $ - $ - $ - $ 903 Tree training $ - $ - $ - $ 60 $ - $ - $ 1 $ 1 $ - $ - $ - $ 62 Groundcover management $ - Debris shredding $ - $ - $ - $ 92 $ - $ - $ 482 $ 321 $ 472 $ 545 $ 212 $ 2,123 Flame weeding $ - $ - $ - $ - $ 9 $ - $ - $ - $ - $ - $ 9 $ 18 Hand weeding $ - $ - $ - $ 11 $ 9 $ - $ 6 $ 34 $ 14 $ 23 $ 22 $ 119 Herbicide application $ - $ - $ - $ - $ - $ - $ - $ - $ - $ 23 $ - $ 23 Mechanical tillage $ - $ - $ - $ - $ - $ 1,927 $ 482 $ 321 $ 482 $ - $ - $ 3,211 Mowing $ - $ 344 $ 355 $ 413 $ 189 $ 315 $ 57 $ - $ 229 $ 367 $ 734 $ 3,004 Mulch application $ - $ - $ - $ 1,148 $ - $ - $ 1,147 $ - $ 1,147 $ 1,147 $ - $ 4,588 Orchard maintenance $ - Fertilizer application $ - $ - $ - $ - $ - $ - $ 0 $ 0 $ - $ - $ 30 $ 31 Irrigation maintenance $ - $ - $ - $ 0 $ - $ 1 $ 0 $ - $ - $ 0 $ - $ 2 Pollen application $ - $ - $ - $ - $ - $ 1 $ 6 $ 6 $ 3 $ 176 $ - $ 192 Pruning $ - $ - $ - $ - $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 1 Spraying $ - $ - $ - $ 37 $ 1,548 $ 2,771 $ 1,978 $ 2,752 $ 1,806 $ 1,548 $ 1,462 $ 13,903 Vertebrate mangement $ - $ - $ - $ - $ - $ - $ 1 $ 1 $ - $ - $ - $ 3 Cropload management $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - Total equipment $ 1,835 $ 2,362 $ 1,646 $ 5,233 $ 1,755 $ 5,015 $ 4,160 $ 3,437 $ 4,153 $ 3,829 $ 2,469 $ 35,894 Equipment % of total costs 64% 48% 26% 9% 22% 38% 33% 22% 32% 27% 31% 23%

Inputs Crop protection materials Gen Insecticides $ - $ - $ - $ - $ - $ 483 $ 62 $ 351 $ 119 $ 119 $ 356 $ 1,490 Kaolin clay $ - $ - $ - $ 116 $ 125 $ 646 $ 420 $ 476 $ 937 $ 511 $ 710 $ 3,942 CM granulosis virus $ - $ - $ - $ - $ - $ - $ - $ - $ 927 $ 881 $ 311 $ 2,118 Lep Insecticides $ - $ - $ - $ - $ 66 $ 437 $ 160 $ 385 $ 952 $ 414 $ 444 $ 2,859 Miticide (oil) $ - $ - $ - $ - $ 56 $ 55 $ 140 $ 120 $ 108 $ 62 $ 62 $ 604 Mating Disruption $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ 245 $ 245 Fungicides $ - $ - $ - $ 21 $ 377 $ 629 $ 512 $ 569 $ 600 $ 416 $ 453 $ 3,576 Bactericides $ - $ - $ - $ - $ 341 $ 9 $ 97 $ 287 $ 181 $ 263 $ 129 $ 1,307 Fertilizers $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - Granular blended $ - $ - $ - $ - $ - $ 1,154 $ 516 $ 516 $ 598 $ 1,601 $ 393 $ 4,778 Foliar $ - $ - $ - $ - $ 38 $ 178 $ 193 $ 133 $ 78 $ 407 $ 307 $ 1,335 Compost $ - $ - $ - $ 11,212 $ - $ - $ - $ - $ - $ - $ - $ 11,212 Lime $ - $ 314 $ - $ - $ - $ - $ - $ - $ - $ - $ - $ 314 Groundcover management $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - Herbicides $ - $ - $ - $ - $ - $ - $ - $ - $ - $ 1,550 $ - $ 1,550 Mulch $ - $ - $ - $ 759 $ - $ - $ 1,914 $ - $ 1,914 $ 1,914 $ - $ 6,500 seed $ - $ 781 $ 3,114 $ - $ - $ - $ - $ - $ - $ - $ - $ 3,895 Orchard management $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - Trellis materials $ - $ - $ - $ 10,453 $ - $ 442 $ - $ - $ - $ - $ - $ 10,895 Irrigation materials $ - $ - $ - $ 1,687 $ - $ - $ - $ - $ - $ - $ - $ 1,687 Tree training materials $ - $ - $ - $ 395 $ 179 $ 90 $ 60 $ 105 $ - $ - $ - $ 828 Vole protection $ - $ - $ - $ 1,046 $ - $ - $ - $ - $ - $ - $ - $ 1,046 Pollen $ - $ - $ - $ - $ - $ 60 $ 82 $ 233 $ 140 $ 233 $ 93 $ 841 Planting stock $ - $ - $ - $ 12,976 $ - $ - $ - $ - $ - $ - $ - $ 12,976 Total inputs $ - $ 1,095 $ 3,114 $ 38,666 $ 1,181 $ 4,184 $ 4,156 $ 3,175 $ 6,554 $ 8,369 $ 3,504 $ 73,999 Inputs % of total costs 0% 22% 49% 69% 15% 32% 33% 20% 50% 58% 45% 48% Total management costs $ 2,867 $ 4,891 $ 6,337 $ 55,747 $ 8,032 $ 13,270 $ 12,688 $ 15,614 $ 12,981 $ 14,384 $ 7,856 $ 154,665

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Orchard 2

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Total Labor Orchard establishment Planting/preparation $ - $ - $ - $ - $ - $ - $ - $ - $ - Grafting $ 4,327 $ - $ - $ - $ - $ - $ - $ - $ 4,327 Trellis construction $ - $ - $ - $ - $ - $ - $ - $ - $ - Tree training $ 270 $ 566 $ - $ 34 $ - $ - $ - $ - $ 871 Groundcover management $ - Debris shredding $ 486 $ 313 $ 727 $ 211 $ 85 $ 148 $ 239 $ 85 $ 2,293 Flame weeding $ - $ - $ - $ - $ - $ - $ - $ - $ - Hand weeding $ 51 $ 254 $ - $ 304 $ 549 $ 406 $ 135 $ 135 $ 1,834 Herbicide application $ - $ - $ - $ - $ - $ - $ - $ - $ - Mechanical tillage $ - $ - $ - $ - $ - $ - $ - $ - $ - Mowing $ 112 $ 232 $ 317 $ 42 $ - $ 190 $ 190 $ 232 $ 1,317 Mulch application $ - $ - $ - $ - $ - $ - $ - $ - $ - Orchard maintenance $ - Fertilizer application $ - $ - $ - $ 135 $ 51 $ 51 $ 135 $ 42 $ 414 Irrigation maintenance $ - $ - $ - $ 68 $ - $ - $ 101 $ 203 $ 372 Pollen application $ - $ - $ 8 $ 68 $ 51 $ 17 $ 63 $ - $ 207 Pruning $ - $ 287 $ 423 $ 1,006 $ 676 $ 1,200 $ 845 $ 1,310 $ 5,747 Spraying $ 1,564 $ 782 $ 866 $ 761 $ 761 $ 887 $ 761 $ 634 $ 7,015 Vertebrate mangement $ - $ 135 $ - $ 17 $ 17 $ 51 $ - $ - $ 220 Cropload management $ - $ 963 $ - $ - $ - $ - $ - $ - $ 963 Total Labor $ 6,810 $ 3,533 $ 2,341 $ 2,645 $ 2,189 $ 2,950 $ 2,470 $ 2,641 $ 25,580 Labor % of total costs 72% 35% 30% 27% 27% 28% 22% 28% 33%

Equipment Orchard establishment Planting/preparation $ - $ - $ - $ - $ - $ - $ - $ - $ - Grafting $ 347 $ - $ - $ - $ - $ - $ - $ - $ 347 Trellis construction $ - $ - $ - $ - $ - $ - $ - $ - $ - Tree training $ - $ - $ - $ - $ - $ - $ - $ - $ - Groundcover management $ - Debris shredding $ 204 $ 85 $ 85 $ 490 $ 206 $ 348 $ 571 $ 206 $ 2,194 Flame weeding $ - $ - $ - $ - $ - $ - $ - $ - $ - Hand weeding $ 5 $ - $ - $ 30 $ 55 $ 41 $ 14 $ 14 $ 158 Herbicide application $ - $ - $ - $ - $ - $ - $ - $ - $ - Mechanical tillage $ - $ - $ - $ - $ - $ - $ - $ - $ - Mowing $ 90 $ 254 $ 254 $ 34 $ - $ 152 $ 338 $ 595 $ 1,716 Mulch application $ - $ - $ - $ - $ - $ - $ - $ - $ - Orchard maintenance $ - Fertilizer application $ - $ - $ - $ 1 $ 0 $ - $ - $ 27 $ 28 Irrigation maintenance $ - $ - $ - $ 0 $ - $ - $ 1 $ - $ 1 Pollen application $ - $ 1 $ 1 $ 7 $ 5 $ 2 $ 104 $ - $ 119 Pruning $ - $ 9 $ 9 $ 205 $ 1 $ 4 $ 2 $ 3 $ 233 Spraying $ 703 $ 2,079 $ 2,079 $ 1,826 $ 1,826 $ 2,130 $ 1,826 $ 1,521 $ 13,989 Vertebrate mangement $ - $ - $ - $ 0 $ 0 $ - $ - $ - $ 0 Cropload management $ - $ - $ - $ - $ - $ - $ - $ - $ - Total equipment $ 1,348 $ 2,427 $ 2,427 $ 2,593 $ 2,093 $ 2,676 $ 2,854 $ 2,366 $ 18,785 Equipment % of total costs 14% 24% 31% 27% 26% 25% 26% 25% 25%

Inputs Crop protection materials Gen Insecticides $ 178 $ - $ 553 $ 73 $ 415 $ 137 $ 141 $ 669 $ 2,166 Kaolin clay $ - $ 826 $ 775 $ 618 $ 564 $ 1,036 $ 605 $ 572 $ 4,996 CM granulosis virus $ - $ - $ - $ - $ - $ 1,068 $ 1,043 $ 368 $ 2,479 Lep Insecticides $ 56 $ 146 $ 517 $ 463 $ 729 $ 1,098 $ 473 $ 727 $ 4,209 Miticide (oil) $ 99 $ 178 $ 66 $ 166 $ 196 $ 125 $ 73 $ 147 $ 1,050 Mating Disruption $ - $ - $ - $ - $ - $ - $ - $ 247 $ 247 Fungicides $ 555 $ 489 $ 760 $ 668 $ 703 $ 666 $ 478 $ 585 $ 4,904 Bactericides $ 25 $ 381 $ 11 $ 115 $ 340 $ 195 $ 342 $ 153 $ 1,562 Fertilizers $ - $ - $ - $ - $ - $ - $ - $ - $ - Granular blended $ - $ - $ - $ 625 $ 456 $ 456 $ 1,722 $ 465 $ 3,724 Foliar $ - $ 81 $ 211 $ 234 $ 153 $ 52 $ 477 $ 389 $ 1,596 Compost $ - $ - $ - $ - $ - $ - $ - $ - $ - Lime $ - $ - $ - $ - $ - $ - $ - $ - $ - Groundcover management $ - $ - $ - $ - $ - $ - $ - $ - $ - Herbicides $ - $ - $ - $ - $ - $ - $ - $ - $ - Mulch $ - $ - $ - $ - $ - $ - $ - $ - $ - Cover crop seed $ - $ - $ - $ - $ - $ - $ - $ - $ - Orchard management $ - $ - $ - $ - $ - $ - $ - $ - $ - Trellis materials $ - $ - $ - $ - $ - $ - $ - $ - $ - Irrigation materials $ - $ - $ - $ 1,387 $ - $ - $ - $ - $ 1,387 Tree training materials $ 423 $ 340 $ - $ 38 $ - $ - $ - $ - $ 801 Vole protection $ - $ 1,832 $ - $ - $ - $ - $ - $ - $ 1,832 Pollen $ - $ - $ 76 $ 155 $ 295 $ 88 $ 412 $ 236 $ 1,261 Planting stock $ - $ - $ - $ - $ - $ - $ - $ - $ - Total Inputs $ 1,337 $ 4,272 $ 2,969 $ 4,541 $ 3,852 $ 4,921 $ 5,766 $ 4,557 $ 32,215 Inputs % of total costs 14% 42% 38% 46% 47% 47% 52% 48% 42% Total management costs $ - $ - $ - $ 9,496 $ 10,232 $ 7,737 $ 9,779 $ 8,134 $ 10,547 $ 11,091 $ 9,564 $ 76,580

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