Performance of ten elite Chinese chestnut cultivars in replicated trial over 16 years in central Missouri

Chinese chestnut is an emerging specialty crop in the midwestern USA. Long-term evaluation of elite Chinese chestnut cultivars is limited in the USA, leading to grower uncertainty. To inform Mid-Missouri growers on cultivar adoption, a replicated trial was established in 1999 at the Horticultural and Agroforestry Research Farm (New Franklin, Missouri, USA), consisting of five complete randomized blocks (8.1×8.1 m spacing). Ten promising cultivars of predominately Castanea mollissima ancestry were field grafted onto C. mollissima rootstock on deep, fertile, well drained, erodible loess soil of the Missouri River hills. Yield (kg tree^‑1) and kernel weights (g) were collected 11 times over a period of 16 years (2007-2011, 2015, 2017, and 2019-2022). Additional kernel quality (17) and phenological parameters (11) were evaluated during 2020-2022. ‘Qing’ produced the highest yields during 9 of the 11 years that data were collected. ‘Payne’ produced the highest yields in 2020 and 2021. The highest average single season yield was achieved by ‘Payne’ in 2021 averaging 45.5 kg tree^‑1. 30-nut samples were evaluated for weight, dimension, percent defect, ease of peeling, pellicle thickness, pellicle adhesion to kernel, and flesh color to gauge overall quality. Nut weight (g) varied year to year and was influenced by moisture availability and crop load. Data collected over a 16-year period (n=11) revealed nut weights averaging between 10.1 and 15.4 g, with ‘Peach’ the heaviest and ‘Perry’ the lightest. Total variation (%CV) for nut weight (g) was lowest for ‘Mossbarger’ (8.2%) and ‘Peach’ (8.6%) and highest for Qing (23.6%), due to its 2017 crop. Variation in phenology, harvest time, harvest window, percent nut defect, and other quality parameters were also significant among cultivars.