Exploring North America's Oldest Food Forest
A truly magical place hides in plain sight in a suburb of Philadelphia. It contains the living history, and the potential future, of agriculture in North America. In history, scope, and potential it outshines almost every agroforestry project, university research station, or permaculture farm in the continental United States.
In 1953, J. Russell Smith called it “America’s No. 1 Tree Crop Farm.” Bill Mollison used it as a model for temperate permaculture. John Hershey’s Nut Tree Nursery in Downingtown, PA - less than an hour outside Philadelphia - is perhaps the most important collection of fruit and nut trees ever assembled on this continent, and though it was shuttered and subdivided after Hershey’s untimely death in 1967, its surviving trees still stand amidst the suburban sprawl of southeastern Pennsylvania. In medians, back yards, parking lots, and overgrown vacant lots you can find towering pecans, blight resistant grafted chestnuts, old nursery rows of grafted black walnuts, the sweetest persimmons, pawpaws, hazelnuts, hickories, sugary pod honey locusts, tannin-free edible acorns, and unsprayed bountiful apples - all of which bear prolifically without any maintenance or care. This treasure trove of trees is North America’s oldest living food forest - a thriving ecosystem, up to a century old in some parts, comprised of the best fruit and nut trees that can be grown here.
Over the past few years a group of small nurserymen, organic farmers, and grass roots ecologists have been exploring these remaining plantings. We have collected seeds, cross-referenced trees with old publications, and networked with other nut and fruit growers around the country to catalog and preserve this incredible place.
In 1921, John Hershey started a small nut tree nursery on 8 acres just east of Downingtown, PA. A decade later, the midst of the Great Depression, the Tennessee Valley Authority (T.V.A.) began a division for tree crops, and at the bequest of J. Russell Smith (the revered author of “Tree Crops: A Permanent Agriculture”), John Hershey left for Tennessee to lead this new division. The work these two men did during a few short years there became the basis for the entire agroforestry movement in the United States, and on his return to Downingtown Hershey expanded his farm to about 75 acres and offered the best of the best from what he had found and grown in Tennessee.
In the 1953 edition of Tree Crops: A Permanent Agriculture, Smith referred to Hershey’s farm and nursery in Downingtown as “America’s No. 1 Tree Crop Farm,” and included a map of the site that we have used to locate some of the surviving trees.
Smith’s seminal work would become one of the most significant inspirations for Permaculture’s co-founder Bill Mollison, and the book’s subtitle (“A Permanent Agriculture”) was shortened into the portmanteau “permaculture” itself. Mollison even adapted this same map in later publications to demonstrate a model layout of an existing tree crop farm for temperate zones.
A farmer decades ahead of his time, Hershey was advocating organic farming in the 1940’s - particularly noting the value of mulching. Like Smith, he had seen the way that unsustainable and extractive agricultural systems robbed the land of topsoil and caused droughts, floods, and the Dust Bowl.
Smith and Hershey presaged and inspired many of the future tenets and strategies of the permaculture movement espoused by Bill Mollison and others. They saw tree crops as the key foundation of an agriculture that provided food for people, timber, and feed for livestock. Hershey, for instance, recommended the following for hog feed: “all the nuts, the American triplets [honey locust, persimmon, and white oak], their little sisters the mulberries and paw paws”; for chickens he recommended serviceberry, mulberry, persimmon, pawpaw, mountain ash, haws and hawthorn, and cracked nuts for winter feeding. Only in the past few years have more farmers begun exploring these recommendations and creating robust silvopastural systems for livestock based on tree crops.
Hershey and Smith revived and developed many of the crops and systems that sustainable farmers are only now beginning to realize are the future of agriculture in North America. A major aspect of this was finding and preserving the best genetics of each tree crop at a time when those trees still existed in the landscape.
Because they held competitions for farmers to submit the best examples of each tree crop, often published in rural newspapers, they were able to crowdsource the best genetics from across the Eastern Seaboard. Many of the finalist submissions became named cultivars that were propagated by Hershey and others for decades to come. These often came from old farmsteads in the South that had preserved the trees from pre-industrial times - farmsteads that often have since been paved over and developed.
Oftentimes, these trees were likely the direct work, or the recent descendents, of the superior selections made by indigenous farmers in the region prior to colonization. For example, 3 of the 4 best selections of honey locust came from areas of the South that comprises the Cherokee homeland. The Cherokee have a long and established history of revering and making use of the honey locust, so it is not unlikely that these Gleditsia selections are, in fact, Cherokee trees. Indeed, most of the tree crops that Hershey and Smith grew and propagated are known to have been the staples of indigenous forest gardening systems throughout the Southeast, which were usually destroyed through logging or neglect by colonists. In this respect, visiting and studying Hershey’s collection of trees is an opportunity to witness and honor thousands of years of indigenous ecological management and horticulture in North America.
The Hershey trees, then, are not just the future of food production for our bioregion - they are the living history of a truly sustainable and regenerative agriculture that has existed here since before European settlers ever arrived. The superior varieties of hickories, honey locust, persimmon, white oaks, and other native trees are the pinnacle of centuries of breeding and selection by indigenous and American farmers. It is not an exaggeration to say that all of us who have visited the Hershey nursery have felt the weight and the sanctity of this history, and we walk through these towering sentinels as if visiting a holy place. It also hurts all the more when we see these trees fall to the chainsaws and machinery of developers who would see champion trees removed to place a parking lot, as is currently happening.
Finally, these trees are vitally important and irreplaceable for another reason. As climate change begins to affect our region in earnest, bringing highly unpredictable weather patterns and temperature extremes, all of the plants around us are increasingly being pushed to their biological limits. The majority of tree crop genetics that John Hershey crowdsourced came from farmers in the Deep South, where the summer highs and heat index resemble what is projected for our region in the next 50 years. These trees, then, are likely able to withstand high temperatures for prolonged periods, in addition to the accompanying fungal and pest issues often found in the Deep South.
Furthermore, these trees have survived the past 50 to 100 years in eastern Pennsylvania with essentially no maintenance. Former nursery rows grew into a thick jungle, and the weakest trees were weeded out by the strongest - leaving only the most robust specimens. This food forest literally created itself as a highly diverse and productive system out of the nursery stock. The remaining trees were never watered or fertilized, rarely pruned, and certainly never sprayed. The ones that survive today are therefore the best of the best - tree crop genotypes that can withstand Deep Southern heat (heatwaves over 100° F), harsh northern frosts (as low as -16° F), urban stresses like pollution and root damage, soil compaction, and complete and utter neglect for decades - yet still produce an abundant and high-quality crop on an annual or biennial basis. Because most of the trees are native, they support exponentially more biodiversity than popular non-native crops as well. If we want to create an abundant perennial agricultural system for our region that requires almost no maintenance and can withstand the worst projections for climate change in the next century, these trees are the answer.
Anyone who cares about our ability to grow food in the next 100 years should know about this place. The oldest food forest in North America shows us both where we have come from, and where we need to go if we want to thrive in an uncertain future.
Species of Lepidoptera (moths & butterflies) supported: 46
The first of the “American Triplets” popularized by J. Russell Smith and John Hershey - the American persimmon (Diospyros virginiana) - is an astoundingly delicious fruit. The trees at the Hershey nursery produce an abundance of fruit every Fall that is quickly eaten by deer, rodents, birds, and yellow jackets. Indeed, Hershey particularly touted the persimmon as an animal feed, noting that they’ll produce 5 tons of valuable livestock feed per acre on land that would be difficult to grow corn on.
Quercus alba, Q. macrocarpa, Q. muehlenbergii, Q. cerris, etc.
Species of Lepidoptera (moths & butterflies) supported: 534
Hershey grew and tested white oaks extensively, noting their longstanding use as a staple crop for people and ease of propagation. He particularly took interest in the ancient sentinels growing in his local landscape, and grew many seeds from the “William Penn Oaks” - specimens throughout Southeast Pennsylvania that were mature trees in the 1680’s. These trees often proved to be superior stock. His work with the TVA additionally turned up white oaks with acorns “practically free of tannin bitterness, sweet as Japanese chestnuts.”
For animal feed, he particularly liked the giant acorns produced by bur oak (Quercus macrocarpa), noting that it grafts well onto white oak, and produces acorns three years after grafting. Like the other white oaks he grew, these bur oak selections had low tannin acorns and grew quickly. Two of the largest at the site are planted at the Downingtown Quaker meeting house. Having seen how the bur oaks here produce huge acorns in the thousands, and how the local wildlife relishes them, it is easy to imagine that they would be perfect for silvopasture systems and food plots for hunters.
Gleditsia triacanthos var. inermis
Species of Lepidoptera (moths & butterflies) supported: 46
The final member of the “American Triplets,” superior selections of honey locust (Gleditsia triacanthos) were among the most significant contributions that Hershey ever made - and their potential still has yet to be realized. Hershey discovered varieties (“Millwood,” “Calhoun,” “Hershey,” and “Schofer”) of this native nitrogen-fixer that are thornless and produce 1.5+ ft. pods that are up to 40% sugar - an incredible and still untapped source of sweetener and calories. He found that the trees reliably produce hundreds of bushels of oat-quality feed per acre for livestock in fall and winter.
In one Downingtown back yard, there are a number of these superior honey locust trees growing. The owners mow regularly beneath the trees, essentially creating a honey locust savannah that approximates the megafauna-dependent habitat they’ve evolved for, as well as what they would look like in a modern silvopastural system for livestock feed.
Species of Lepidoptera (moths & butterflies) supported: up to 127
Hershey started growing Japanese chestnuts, but by the late 1940’s was convinced that Chinese chestnuts were superior for our region. Throughout the literature he repeatedly recommended growing seedlings, as they come fairly true from seed and grafted trees can be risky. He offered seedlings from two varieties he named - a timber-type Chinese chestnut that he dubbed “Sky Climber” and recommended for timber plantings, as well as a variety called “Abundance” whose seedlings he said were often better than the grafted parent. Furthermore, he recommended planting black locust (Robinia pseudoacacia) at 6x6 ft. spacing in between chestnuts and walnuts, in order to fix nitrogen and push the growth of the nut trees.
Juglans nigra, J. cinerea, J. regia
Species of Lepidoptera (moths & butterflies) supported: 130
Hershey grafted and sold a number of black walnut (Juglans nigra) cultivars. He noted that seedlings of the “Thomas” variety make the best rootstock for walnuts, except in the far north. For customers in cold areas, he used Minnesota black walnuts for understock, and seedlings of a nut from Utah that survives and bears nuts in areas under 12-16 inches of rainfall for drier areas in the West. He also grafted and sold selections of English Walnut (Juglans regia) - the kind we most often find in stores - grafted on Black Walnut rootstock.
Pecan, Hickory, and Hican
Carya illinoinensis, C. ovata, C. cordiformis, Carya hybrids
Species of Lepidoptera (moths & butterflies) supported: 235
Hershey introduced the “Grainger” cultivar of shagbark hickory (Carya ovata), now the standard against which all other cultivars are measured for the species. Additionally, he planted an extensive collection of cold hardy pecans (Carya illinoinensis, cultivars “Busseron,” “Greenriver,” and “Indiana”) that still produce an incredible quantity of high-quality nuts.
One of the most incredible sights for those who visit the Hershey nursery is the size of Hican (pecan x hickory hybrids) nuts. Some of these, presumably the “McAllister” or “Bixby” variety, are the largest nuts produced on this continent. Many of these hican trees are likely the oldest of their kind in existence.
Other varieties of hicans can be found throughout the site as well, including “Burton” whose seedlings are particularly known to produce high-quality nuts.
Species of Lepidoptera (moths & butterflies) supported: 311
At a few locations we have found an exceptional crabapple that holds its fruit late into the winter. It has a sweet-tart taste that is excellent for cider, baking and cooking, and even fresh eating for those who like somewhat tart apples. Most impressively, it produces a huge crop annually - avoiding the curse of biennial bearing that is common to most apples. Even in years when disease and pest pressure is heavy in apples throughout the region, these crabapples are unbothered and produce excellent blemish-free fruit without any sprays or maintenance. I have not yet found another cultivar with this quality of fruit that performs so well without sprays here. It’s exact cultivar is still unknown - we first thought it was “Callaway” based on visual assessment, but after consulting Hersheys catalogs we now believe it is either “Hopa” or “Manchurian.”
In addition to the trees profiled here, Hershey also offered hybrid poplars, redbud, silver bell, blueberries, mulberries, highbush cranberry viburnum, coral berry, mountain ash, Washington hawthorn, blackberries, sugar maple, and other tree crops with great potential. While exploring the nursery, we have also come across some oddities that we have yet to find an answer for - such as grafted beech trees, and large pecans that were grafted twice, creating an interstem about 20 feet high.
While it is a miracle that so many trees have survived five decades of development and urbanization, they are still under immediate threat. There are members of the city government in Downingtown who now realize how special this collection of trees is, but more organizing and education for the public is needed to make sure the remaining trees are looked after and not removed so easily. In the meantime, our group ventures out every year to collect seeds and cuttings, and to record and discover what still remains. The dream of Hershey and Smith is experiencing a rebirth with the renewed global interest in permaculture and agroforestry. We hope that this site can be a model and source of inspiration for future generations, and help guide the way toward an ecologically regenerative agriculture in our bioregion.
The research in this article has been painstakingly compiled by a number of people who have generously volunteered their time toward this project. Dale Hendricks of Green Light Plants, Buzz Ferver of Perfect Circle Farm, Zach Elfers of Nomad Seed Project, Adam Dusen of Hundred Fruit Farm, Taylor Malone, and - most importantly - Pete Chrisbacher, who knew about this site before any of us, and spent years gathering, scanning, and generously sharing many of Hershey’s catalogs and publications with us. For the intrepid fruit nuts out there, these documents can be publicly accessed here.