What is the most productive apple rootstock?
I'm curious, could you elaborate on what factors are typically considered when determining the productivity of an Apple rootstock? Are there certain varieties that are known for their superior fruit-bearing capabilities, or is it more of a combination of soil type, climate, and cultivation techniques? Additionally, are there any recent advancements in apple rootstock research that have led to the development of more productive strains? I'm eager to learn more about this topic, as I'm interested in optimizing the yield of my apple trees.