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.
Pecans, hicans, hickories, black walnuts, white oaks, maples, persimmons, and honey locusts - most of the trees grafted varieties - create a dense, productive canopy
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.
The History
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.
Hershey’s farm and nursery was incredibly diverse and held an enormous wealth of every type of tree crop imaginable: filberts, blueberries, English and Black walnuts, chestnuts, peaches, cherries, pears, jujubes, sugar maples, chinkapin and bur oak, mulberries, wild plums, persimmons, honey locust, more oaks, pecans, hicans, hickories, and more.
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 mature honey locust between former nursery rows. Over the decades after the farm was abandoned, the trees grew into a “jungle” where the weakest trees were shaded out. The trees that remain are the strongest and most resilient. This food forest literally created itself as a highly diversified and productive system. The only maintenance it receives is periodic mowing.
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.
Grafted hickories in a back yard. Hickories, including bitternut hickory (Carya cordiformis), are one of the most underutilized (and most delicious) 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.
“Hershey’s tree-crops section in the T.V.A. offered prizes for the best acorns, the best honey-locust pods, the best persimmons, the best blueberries, and other wild fruits… Hershey’s most important find was the Milwood Honey Locust and the Calhoun - both of which produce above thirty percent sugar”
Timber-form chestnut, hickories, persimmons - many of them grafted varieties that Hershey discovered while working at the T.V.A.
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.
Gathering giant “Bixby” or “McAllister” hican nuts from a truly massive tree - about at 100 ft. tall and wide. This particular tree is slated to be destroyed this winter to make way for a new housing development.
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.
The Trees
American Persimmon
Diospyros virginiana
Species of Lepidoptera (moths & butterflies) supported: 46
Hershey grew an incredible diversity of American persimmons displaying different shapes and colors - reds, oranges, purples, greens, and more.
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.
Thousands of ripe persimmons litter the ground in early Fall
“Fall of ‘65 with no rain - grass growth at a “stall”, 60 young [persimmon] trees fed our 25 herd 2 months, grew and fattened; 15 sheep 4 weeks, from late September till last week of November, then started to look for hay. Think of it. With little loss of hay and pasture crop in the orchard this tremendous crop of persimmons, 35% sugar, 10% protein plus many other feed elements; plus the potent oil and protein in seed it really excites you. Can you afford to slug along without them?”
A grafted persimmon - with its distinctive bark - stands amidst honey locusts, pecans, hicans, and black walnuts
Oak
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.”
Bur oak acorns drop abundantly in early October. I was able to gather 500 of these enormous acorns by hand in less than half an hour. Pigs or deer could swoop them up much faster, if given the chance.
“Here’s the center piece - the keystone of the American Triplets. This back bone of American frontier life and today’s wood industry, would make more for man in annual crops than our coal mines, if we would put our minds to work on it. Here’s why. These are the “corn fields of the future.” When man grows up to use what he has, he’ll Oak a mountain ridge, a hill-side, a rocky knoll. According to production figures of bearing oaks a low of 274 bushels of corn per acre in hog food value can be grown on mountains and steep slopes.”
Hershey collected and grew the largest specimens of bur oak acorns he found. Photo courtesy of Buzz Ferver.
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.
Honey Locust
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.
Plump, sugary pods on grafted varieties can grow over 18 inches long.
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.
The honey locust selections tend to bear biennially - however, different varieties bear in different years. This tree produced very little last year, however there was a large crop on other trees. Planting different varieties will ensure a dependable crop every year.
This planting shows how honey locusts could be part of silvopasture systems - or integrated into annual grain or vegetable fields. The leaves provide dappled shade, allowing for most annuals to grow beneath them.
Chestnut
Castanea mollissima
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.
These Chinese chestnuts, still growing in untended hedges with an understory of invasive bush honeysuckle, have grown to enormous size in 50+ years - about 4 feet in diameter at breast height
Chestnut burs hang heavy on the branches of a young seedling chestnut near some of the older specimens
Walnut
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.
Average sized black walnut (left) beside a black walnut from a grafted tree (right) near the Meetinghouse
Black walnuts bear abundantly every year
This is a triple grafted walnut: black walnut rootstock, 2 grafted butternut (Juglans cinerea) varieties, and third graft of a highly unusual single-lobed walnut that is easier to crack and great for home production
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.
An enormous (100+ ft. tall & wide) pecan tree - one of many of this size. These trees are likely nearly a century old, and are slated for removal this year by a developer.
We gathered hundreds of pecans from just the lowest branches that we could reach. Looking up into the canopy of a giant tree like this, it is clear what the productive potential is for tree crop systems in the Northeast.
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.
Giant nuts from the “Bixby” or “McAllister” hican. These are the largest nuts that can be grown in North America.
Other varieties of hicans can be found throughout the site as well, including “Burton” whose seedlings are particularly known to produce high-quality nuts.
Crabapple
Malus sp.
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.”
Delicious crabapples larger than a quarter, bearing abundantly every year without sprays. These will hang on late into winter.
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.
A blight-resistant hazelnut, growing and fruiting beneath an overstory of honey locust (Gleditsia triacanthos var. inermis), Turkey oak (Quercus cerris), and Chinese chestnut (Castanea mollissima), near another understory stand of pawpaw (Asimina triloba)
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, Zach Elfers, Adam Dusen, Buzz Ferver, 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.