UNIVERSITY PARK, Pa. — One glance at a commercial orchard today and you realize these aren't your grandfather's apple trees. Long gone are the 40-foot-high, widely spaced, gnarled and spindly trees of the past. They have been replaced by squat, tightly planted trees loaded with low-hanging fruit.
Key to the transformation has been research conducted at Penn State and other land-grant universities, and Penn State horticulture professor Rob Crassweller has been at the forefront of the effort to boost apple production for more than 30 years. In his role as a faculty member with Penn State Extension, he has presented those findings to growers.
The University's College of Agricultural Sciences has been conducting research on apple tree rootstock at the Russell E. Larson Agricultural Research Center at Rock Springs since the early 1970s, when horticulturists from a number of universities in the Northeast banded together to form a project called NC-140. That federally funded initiative continues today and Penn State will host its annual meeting in November.
"It is a group of us involved in pomology representing 20-some states, three Canadian provinces, and even a cooperator in Mexico," Crassweller said. "We have been cooperatively evaluating rootstock since the mid-'70s because rootstock controls tree size, and we must have size control since we don't want trees to be 40 feet tall. We want them to be no more than 14 feet high — so we can pick all of the fruit from the ground."
In recent years, Crassweller has also been working with the Midwest Apple Improvement Association, helping it evaluate and develop new cultivars. New apple varieties created by breeders have revolutionized the apple industry, he noted. For example, the Honeycrisp variety — which he had a hand in evaluating — has set the apple market on its ear.