The tall spindle orchard design that is being so steadfastly encouraged by researchers—and adopted by growers—in the eastern United States came about from the discovery of ­several important principles. In the 30 years he has been working to develop the tall spindle system, Cornell University’s Dr. Terence Robinson said he was guided by five principles: 1. Studies on light interception showed that the highest yields required that trees intercept 70 to 75 percent of the light. Growers who wanted pedestrian orchards of around eight feet tall couldn’t achieve that unless they went to very narrow alleys that are too narrow […]