Table 3. Stem and leaf carbon isotope composition (‰) for 2018 and 2019 of ‘Honeycrisp‘ apple trees on B.9, M.9, G.969, CG.4292, G.210, G.87, CG.5257, G.814, G.890 rootstocks measured in 2018 and 2019. Different letters indicate significance differences among means determined using a Tukey‘s mean separation test (α=0.05).