John Walter Hershey (February 5, 1898September 7, 1967) was a fruit and nut orchardist of Pennsylvania, United States. He worked for the U.S. government during the Dust Bowl, teaching farmers how to grow perennial food crops in order to diversity their incomes and their farm ecosystem. Many of the trees he grafted onto rootstock and planted in the vicinity of his Downington, Pennsylvania plant nursery remain standing and continue to produce fruit and nuts.
Hershey was born in Paradise, Pennsylvania, in the Pennsylvania Dutch country. He was a distant cousin of Milton Hershey of chocolate bar fame. He grew up on a farm and obtained a high school education. In early adulthood he worked as a bond salesman, and a railroad man. His formal education as an agronomist was nil, he was self-educated, with support only from mentors. He started his career in agroforestry with J. F. Jones, who was the "originator of a method of grafting nut trees."
Hershey started his own nut tree nursery in 1922. His nursery was on the Lincoln Highway "just east of the borough line" in what he described as "picturesque Yankee town located in a long fertile valley fringed with tree-covered hills." At the nut tree nursery he worked on breeding and crossbreeding different strains of North American nut trees, for example working on a successful cross between a pecan and a shellbark hickory. He also edited a periodical called The Nut Grower's Guide. He also advocated for planting food sources for wildlife, suggesting that farmers start "food plants on their rough knolls, slopes, ditches and edges of woodland. Of the berries and fruits, the best are the chokecherries, red and black haws, crabapples, wild plum, cherry, pears, persimmons, honey locust, and many others." He reported high profits from the planting of walnuts and black walnuts, and recommended grafting English and Persian walnuts to American black walnut rootstock.
Hershey worked as an agroforestry project manager for the Tennessee Valley Authority under Franklin Roosevelt's New Deal. The Tennessee River watershed is home to a diverse array of hardwood trees, including several kinds of oaks, tulip poplar, swamp cypress, tupelo gums, and prior to the blight, the American chestnut, many of which were or are commercially significant species.
His residence was at Corner Ketch near Downingtown, Pennsylvania.
Hershey died in Downington at age 69 in 1967. He was posthumously described as "the only honest grafter of Chester County."
Hershey was a member of the Society of Friends Uwchlan Monthly Meeting.