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value-added products (Charlebois et al. 2010). In our study, vegetative and reproductive growth also differed by year, which may be attributed to favorable temperatures and solar radiation in 2023, when plant responses were enhanced. Mean maximum daily tempera tures were generally warmer early in the 2023 growing season (April to June) than in 2022, with greater solar radiation during bloom and flowering, followed by cooler temperatures during fruit enlargement and ripening (July and August). Varying amounts of precipita tion during the different years were likely not a major factor in this study since drip irriga tion was used to prevent low moisture condi tions in the potting medium. Others reported that low soil moisture exacerbated the effect of root pruning (Mika and Krzewinska 1995), while optimal moisture diminished the reduc tion in vegetative growth in apple trees (Mill er 1995; Saure 2007). Moreover, Geisler and Ferree (1984) reported that root regeneration of woody plants is promoted with relatively warm temperatures, good soil aeration, the lack of moisture stress, and relatively high light intensities. In conclusion, this study demonstrated that root pruning reduced shoot growth and limited fruiting on young, container-grown American elderberry plants. However, transplanting into a larger container with or without root prun ing mitigated these negative effects, especial ly when grown under favorable conditions. While root pruning may not be advantageous, refinements in container production of Ameri can elderberry may enhance fruit production. Future research may include optimization of container size, evaluation of growing sub strates and their longevity, plant nutrient re quirements, and pruning frequency. Economic analyses are also needed to determine the fea sibility and profitability of high-density, con tainer-based systems for American elderberry fruit production. Literature Cited Byers PL. 2010. Elderberry possibilities. Univer sity of Missouri. https://grow.midwest-elderberry.

coop/overview/elderberrypresentationmn.pdf. [accessed 2 Nov 2023]. Byers PL. 2014. Overview of elderberry nutrition in Missouri. University of Missouri Extension. https://grow.midwest-elderberry.coop/overview/ byers-overvieweldernutritio.pdf. [accessed 2 Nov 2023]. Byers PL, Thomas AL. 2011. ‘Bob Gordon’ elder berry. J Am Pomol Soc. 65(2):52–55. Byers PL, Thomas AL, Gold MA, Cernusca MM, Godsey LD. 2014. Growing and mar keting elderberries in Missouri. University of Missouri Center for Agroforestry. AF1016. https://centerforagroforestry.org/wp-content/ uploads/2021/05/2014Growing ElderberryGuide. pdf. [accessed 2 Nov 2023]. Byers RE, Yoder KS. 1999. Prohexadione-calcium inhibits apple, but not peach, tree growth, but has little influence on apple fruit thinning or qual ity. HortScience. 34(7):1205–1209. https://doi. org/10.21273/HORTSCI.34.7.1205. Cahoon GA, Shaulis N, Barnard J. 1977. Effect of daminozide on ‘Concord’ grapes. J Am Soc Hor tic Sci.102(2):218–222. https://doi.org/10.21273/ JASHS.102.2.223. Campbell T, Schupp JR, Marini RP. 2022. Reevalu ating summer hedging and root pruning for inten sive apple orchard systems: a review. J Am Pomol Soc. 76(3):136–145. Charlebois D, Byers PL, Finn CE, Thomas AL. 2010. Elderberry: botany, horticulture, poten tial, p 213–280. In: Janick J (ed.). Hortic Rev., vol 37. Wiley, Hoboken, NJ, USA. https://doi. org/10.1002/ 9780470543672.ch4. Curry EA. 1988. Chemical control of vegetative growth of deciduous fruit trees with paclobutra zol and RSW0411. HortScience. 23(3):470–473. https://doi.org/10.21273/ HORTSCI.23.3.470. Darnell RL, Alvarado-Raya HE, Williamson JG. 2008. Root pruning effects on growth and yield of red raspberry. HortScience 43(3):681–684. https://doi.org/10.21273/HORTSCI.43.3.681. Elfving DC, Lombardini L, McFerson JR, Drake SR, Faubion DF, Auvil TD, Van Ee G, Visser DB. 2003. Effects of directed applications of pro hexadione-calcium to tops of mature pear trees on shoot growth, light penetration, pruning, and fruit quality. J Am Pomol Soc. 57(2): 45–57. Fang Y, Nunez GH, Silva MND, Phillips DA, Mu noz PR. 2020. A review for southern highbush blueberry alternative production systems.Agron omy 10(10):1531. https://doi.org/10.3390/agron omy10101531. [accessed 3 Nov 2023]. Ferree DC. 1992. Time of root pruning influences