Long-term effects of rootstock and tree density on the economic profitability of ‘Delicious’ apple orchards in the Northeastern U.S

Abstract

Establishing an apple orchard involves a strategic combination of biological and structural decisions. Factors such as variety, rootstock, tree spacing, training system, and local environmental and economic conditions all interact to influence orchard performance over time. Understanding how these variables affect long-term profitability is essential for growers aiming to maximize returns on investment. This study presents an economic evaluation of a long-term field trial conducted in New York State (Yonder Farm, southeastern region) from 2007 to 2017. The trial focused on ‘Delicious’ apples and assessed the interaction between ten rootstocks (B.118, G.11, G.16, G.210, G.30, G.41, G.935, M.26, M.7, and M.9) and four training systems with varying planting densities: Super Spindle (5,382 trees·ha-1), Tall Spindle (3,662 trees·ha-1), Triple Axis Spindle (2,243 trees·ha-1), and Vertical Axis (1,656 trees·ha-1). Our results show that highdensity systems, Super Spindle and Tall Spindle, consistently delivered the highest profitability, despite their higher initial establishment costs. These systems also achieved faster break-even points and greater cumulative net present value, especially with rootstocks such as G.11, G.210, and G.935. In contrast, lower-density systems like Vertical Axis and Triple Axis Spindle showed slower economic recovery and lower overall returns. The multi-leader Triple Axis Spindle system had lower profitability than higher density single stem systems (Tall Spindle and Super Spindle). This indicates that multi-leader trees planted at lower planting densities than Tall Spindle or Super Spindle with the goal to reduce initial establishment costs does not result in as high profitability as the higher density single stem systems. Profitability was not only influenced by training system but also by the compatibility between rootstock and planting density. Rootstocks such as G.41, G.11, and G.210 performed best under high-density conditions, while B.118 was more suited to low-density systems. Conversely, M.9 and M.7 showed limited economic potential, particularly when used in intensive planting systems. These findings underscore the importance of aligning rootstock vigor and precocity with the structural design of the orchard to optimize long-term economic outcomes.