Effect of hexazinone on species distributions and weed competition in lowbush blueberry fields in Maine.

Lowbush blueberries (Vaccinium angustifolium Aiton and V. myrtilloides Michaux) are produced on native or wild stands in Maine and Eastern Canada. The use of the herbicide hexazinone has caused changes in the weed populations in lowbush blueberry fields. To determine the effect of hexazinone on these species and on the growth and productivity of lowbush blueberries in commercial fields in Maine; blueberry and weed population cover, frequency, and blueberry plant stand and yield were sampled on two fields over four years. Cover and frequency of all species were compared to an earlier survey on 14 fields which had been treated once or twice with hexazinone. Blueberry plant stand was compared among the treated fields. Hexazinone-treated fields had a decline in the cover and frequency of a number of weed species and a corresponding increase in blueberry growth and yield. Open ground, bunchberry (Cornus canadensis L.) and dogbane (Apocynum androsaemifolium L.) increased in cover and frequency with hexazinone treatment. Replacement series experiments to assess competitive effects of bunchberry were established on native stands of blueberries in 1986 and 1987. Quadrats were established on prune and crop fields at cover ratios, where c = crop or blueberry and w = weed or bunchberry of 100c/0w, 75c/25w, 50c/50w, 25c/75w, 0c/100w. Dormant blueberry and bunchberry plugs from prune fields were grown in the above proportions in the greenhouse in the summer of 1987. In the field study, relative yields and regression of individual vs associate yield indicates that blueberry and bunchberry growth are equivalent. Blueberry fruit number and yield decreased with increasing bunchberry density. In the greenhouse study, relative yield, regression of individual versus associate yield, and leaf area index of blueberry and bunchberry indicated that blueberry grew as well or better in mixtures than in prune stands. Replacement series experiments indicated that blueberries are competitive with bunchberry but open areas among clones in native fields allow faster growing bunchberry to spread without competition. Two field experiments indicated that imidazoline compounds did not provide selective control of bunchberry but sulfonyl urea compounds merit further research for bunchberry suppression

History of Maine’s wild blueberry industry

Wild blueberry plants were first established as the glacier receded 10,000 years ago and were used by native Americans, but the commercial industry began in the 1800’s and continued to expand to the 1950’s, when Maine was the largest blueberry producer in the United States. Wild blueberries were first picked fresh by hand, then raked and canned and now are mostly mechanically harvested, and 99% of the crop is frozen and is used principally as an ingredient in processed foods. The crop increased over time from less than one million pounds in 1896 to the bumper crop of over 110 million pounds produced in 2000. It now averages about 100 million pounds which is produced on 44,000 acres, half of which are harvested each year. Harvest techniques from hand-picking to hand-raking, to the current practice of 24 hr/day machine harvesting, have changed over time. Pest challenges that have faced the industry include the blueberry maggot in 1919 to the introduction of the newest pest, the spotted wing drosophila in 2012. Changes in pruning from burning to mowing began when the price of oil increased in the 1970s, when fields were de-rocked, leveled and mowed to reduce cost and facilitate mechanical harvesting. Wild blueberry growers were early adopters of IPM techniques which include fruit fly trapping and border spraying to minimize applications, use of sweep net to monitor for chewing insects, monitoring weather conditions to apply fungicides, leaf sampling to determine fertilizer needs and the use of sulfur to reduce soil pH as a cultural management tool to suppress weeds. These improved weed, disease and insect management techniques, and the increased use of imported pollinators and irrigation, have increased yields and reduced the cost of production allowing wild blueberry growers to be economically competitive

Comparison of multiple post-emergence Callisto applications for spreading dogbane (\u3cem\u3eApocynum androsaemifolium\u3c/em\u3e L.) control in wild blueberry fields

Spreading dogbane (Apocynum androsaemifolium L.) is a major weed pest in wild blueberry (Vaccinium angustifolium Ait.) fields and is difficult to control. In a 2016 trial conducted in a prune year wild blueberry field, spreading dogbane was sprayed post-emergence with mesotrione (Callisto) at 146 mL/ha or 219 mL/ha product per application to 1 x 4 m split plots, with one half also receiving pre-emergence hexazinone (Velpar). Dogbane emergence and growth were monitored, and plots were sprayed when dogbane reached the 3-5 leaf stage and again after regrowth for a total of three Callisto applications for each rate. Although both Callisto-Velpar combinations (93% control in July) and Callisto 219 mL/ha alone (98% control in July) almost eliminated dogbane, and no new seedlings were observed at the fourth evaluation in July, dogbane was not completely controlled by any treatment. Some of the dogbane stems which appeared dead at the third evaluation in June showed regrowth of lateral leaves in July. T-tests comparing Velpar vs no Velpar indicated that the addition of Velpar slightly increased dogbane control and injury, but the effects were not significant at α=0.05. The commercial landowner’s adjacent treatment of a split Callisto application followed by a mid-summer glyphosate wiper application exhibited better long-term control of dogbane, and warrants further investigation

MR445: Maine Wild Blueberry Growers: A 2010 Economic and Sociological Analysis of a Traditional Downeast Crop in Transition

An extensive mail survey of Maine wild blueberry growers was conducted in spring 2010, the first extensive sur­vey of growers in almost three decades (1974). The objective of the survey was to quantify the diversity of growers’ philosophies, management practices, and perspectives on their priorities in producing blueberries. We also wanted to identify the sources of new information upon which growers rely. Our results are based on 100 responses from a grower population of 353. We asked growers to place themselves into one of four categories representing distinct ap­proaches to management: conventional (12%), integrated pest management (IPM, 65%), organic (13%), or no-spray (11%). Conventional and IPM growers incorporated more pesticides into their production than organic and no-spray growers. IPM growers, however, were more likely than conventional growers to monitor their fields for pests and need for fertilizer. Conventional growers harvested fewer acres, made less money from blueberries, and were less likely to attend University of Maine Cooperative Extension (UMCE) meetings than IPM growers. No-spray growers were simi­lar to organic, with a few differences. No-spray growers used herbicides and fertilizers whereas organic growers used sulfur and pulled weeds by hand. No-spray growers made less of their income from blueberries, were less likely to grow blueberries full time, and were less likely to attend UMCE meetings regularly than organic growers. Conventional and IPM growers (pesticide adopters) shared similar goals: making a profit, maintaining land value, providing healthy food for the public, and leaving a legacy for their family. Pesticide-avoiders (organic and no-spray)—characterized by their minimal use of pesticides and lower likelihood to rent or purchase commercial bees—also shared similar goals: provid­ing healthy food for the public, making a profit, and being a steward of the environment. In general a few trends were observed for all growers. Field size was associated with management intensity and education level, and years as a grower had little influence on production practices.https://digitalcommons.library.umaine.edu/aes_miscreports/1017/thumbnail.jp

Proceedings of the North American Blueberry Research and Extension Workers Meeting, 2018 Orono, Maine

The 2018, the North American Blueberry Research and Extension Workers (NABREW) Conference took place August 12-15 at the Wells Conference Center at the University of Maine in Orono. The meeting was conducted by the University of Maine Cooperative Extension, and a welcome was provided by the president of the University of Maine and UMM, Dr. Joan Ferrini-Mundy. This is the second time that this national conference has been held in Maine; the first was in 1966. This year more than 74 participants from 13 states and four other countries - Norway, Canada, Mexico and New Zealand - attended the conference

What Is the Value of Wild Bee Pollination for Wild Blueberries and Cranberries, and Who Values It?

Pollinator conservation efforts and growing interest in wild bee pollination have increased markedly in the last decade, making it increasingly important to have clear and practical estimates of the value of pollinators to agriculture. We used agricultural statistics, socio-economic producer surveys, and agronomic field research data to estimate traditional pollination value metrics and create novel approaches to the valuation of the ecosystem services provided by wild pollinators. Using two regionally important United States (USA) crops—Maine wild blueberry and Massachusetts cranberry—as models, we present the perceived values of wild bee pollinators from the perspectives of both consumers and producers. The net income attributable to wild bees was similar for wild blueberry ($613/ha) and cranberry ($689/ha). Marginal profit from incrementally adding more hives per ha was greater from stocking a third/fourth hive for cranberry ($6206/ha) than stocking a ninth/10th hive for wild blueberry ($556/ha), given the greater initial responsiveness of yield, revenue, and profit using rented honey bee hives in cranberry compared with wild blueberry. Both crops’ producers were willing to annually invest only $140–188/ha in wild pollination enhancements on their farms, justifying government financial support. Consumers are willing to pay ≈6.7 times more to support wild bees than producers, which indicates a potential source for market-based subsidies for invertebrate conservation

Blueberry Progress Reports

The 1980 edition of the Blueberry Progress Reports was prepared for the Maine Blueberry Commission and the University of Maine Blueberry Advisory Committee by researchers with the Maine Life Sciences and Agriculture Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Weed Control in Lowbush Blueberry Fields 2. Pruning of Blueberries 3. Integrated Pest Management of Blueberries in Maine 4. Physiology and Culture of the Lowbush Blueberry 5. Blueberry Diseases: Incidence and Control 6. Insects Affecting the Blueberry 7. Effect of Plant-Water Stress on Lowbush Blueberry Growth, Yield and Quality 8. Blueberry Extension Progress Report 9. Plan of Work -1981- Blueberry Extensio

Blueberry Progress Reports

The 1981 edition of the Blueberry Progress Reports was prepared for the Maine Blueberry Commission and the University of Maine Blueberry Advisory Committee by researchers with the Maine Life Sciences and Agriculture Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Weed Control in Lowbush Blueberry Fields 2. Pruning of Blueberries 3. 1982 Blueberry Fruit Fly Monitoring IPM Program 4. Physiology and Culture of the Lowbush Blueberry 5. Blueberry Diseases: Incidence and Control 6. Control, biology, and ecology of insects affecting lowbush blueberries 7. Blueberry Extension Progress Report 8. Plan of Work - 1982 - Blueberry Extensio

Blueberry Research Progress Reports

The 1989 edition of the Blueberry Research Progress Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Control of Secondary Blueberry Pests 2. Monitory Methods, Economic Injury Levels, and Action Thresholds of Secondary Blueberry Pests 3. Control of Blueberry Maggot 4. Phosphorus Dose/Response Curve 5. Nitrogen-Phosphorus Study 6. Multiple Cropping of Wild Stands 7. Changes in Sugars and Organic Acids of Blueberries During Development 8. Investigation of Preprocess Changes That Could Lead to the Development of a Simple and Inexpensive Method to Measure Preprocess Berry Spoilage 9. Development of Simple and Less Expensive Methods to Analyze Pesticides Used on Maine and Canadian Blueberries 10. Evaluation and Modification of Commercial Wipers 11. Effect of Rate and Formulation of Hexazinone on Bunchberry 12. Bracken Fern Control Alternatives 13. Evaluation of Hexazinone with Spot Treatments of Glyphosate Sethoxydim or Fluazifop-P for Bunchgrass Control 14. Directed Sprays of Glyphosate for Bunchberry Control 15. Evaluation of Norflurazon with or without Hexazinone for Bunchgrass Control 16. Selective Wiper and Mechanical Control of Dogbane 17. Evaluation of Sulfonyl Urea Herbicides for Bunchberry Control 18. Seedling Pruning Study 19. Evaluation of Sethoxydim in Lowbush Blueberry Fields 20. Blueberry Extension Program 21. Pollination of the Low-bush Blueberry by Native Bees 22. Postharvest Fungi of Lowbush Blueberries 23. Effects of Pruning Methods on Mummy Berry Incidenc

Blueberry Advisory Committee Research Report

The 1988 edition of the Blueberry Advisory Committee Research Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Monitoring methods, economic injury levels, and action thresholds for blueberry spanworm larvae in vegetative year fields. 2. Control of secondary blueberry pests 3. Control of blueberry maggot 4. Effect of pruning practices on blueberry insect abundance 5. Survey of Fungi Contaminating Lowbush Blueberries 6. Nutrition Survey 1988 7. Phosphorus Dose/Response Curve 8. Effect of Several Mulches on Frost Heaving, Soil Moisture, Soil Temperature and Rhizome Development 9. Influence of Mulch Sources on Clonal Spread-SCS Study, Deblois 10. Effect of Surface Mulches on Stabilizing Lowbush Blueberry Soil in Barren Areas 11. Nitrogen-Phosphorus Study 12. Changes in Sugar and Organic Acids of Blueberries During Development, Preprocess Lag Time and Storage 13. Characterization of Pectin in Blueberries 14. Effect of Hexazinone (VELPAR) on Species Distribution in Lowbush Blueberry Fields 15. Evaluation of Setyhoxydim (POAST) for Bunchgrass Control 16. Evaluation and modification of commercial wipers 17. Evaluation of Five Preemergence Herbicides for Control of Oatgrass and Bunchgrass 18. Effect of rate and formulation of hexazinone (VELPAR) on bunchberry 19. Bracken fern control alternatives 20. Hexazinone (VELPAR) and terbacil (SINBAR) combinations for weed control 21. Evaluation of hexazinone (VELPAR) with spot treatments of glyphosate (ROUNDUP) or sethoxydin (POAST) for bunchgrass control 22. Directed sprays of glyphosate (ROUNDUP) for bunchberry control. 23. Evaluation of Postemergence Applications of Chlorimuron for Bunchberry Control 24. Seedling Pruning Study 25. Blueberry Harvester Trials 26. Blueberry Extension Progra