It was a routine day in the laboratory belonging to Cameron Peace on the campus of Washington State University, Pullman, in the high, dry hills close to the Idaho border.
Peace is a tree-fruit geneticist, and on this warm September afternoon, as on most days, he was running programs that tease out the DNA profiles of apples.
Apples are Peace’s passion and the focus of his professional expertise.
He maintains a backyard collection of unusual varieties and runs a project called MyFruitTree, which lets members of the public send in leaves from unidentified apple trees and matches those trees’ genetic fingerprints to entries in a database of known types.
Washington State University is a land-grant university, founded to research and support agriculture, and Peace was honoring that mission.
The samples he was examining had come from a team on the other side of the country at the Maine Organic Farmers and Gardeners Association (MOFGA), a long-standing agricultural nonprofit.
The group wanted to identify trees it had found on old and abandoned farms, hoping to salvage valuable rarities before high winds or harsh winters killed them.
Peace does this work because every analysis he runs benefits his central project, a literal family tree of North American apples that traces the distribution of distinctive traits—flavor, color, hardiness, disease resistance—through siblings, parents and forebears.
He plugged the data from a Maine sample coded AMHO-504 into a spreadsheet tool that would compare it against his collection.
Then he sat back, agape.
High up in the continental pedigree the entire DNA fingerprint matched a predicted empty space.
The Maine team had found a living lost progenitor to hundreds of varieties—a tree that had been contributing its characteristics to American apples for hundreds of years.
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A lost piece of apples’ history had suddenly been discovered in North America.
That afternoon three years ago was the culmination of a detective story that spanned continents, collapsed centuries and linked the unlikeliest collaborators.
Two quests drove their efforts.
They wanted to identify a mystery tree on a property that dates back to the American Revolutionary War.
But they also wanted to uncover what the possibly oldest living apple tree in the U.S.
contributed to generations of apple varieties—and, equally, what traits it might still harbor that could be bred back into apples today to protect them against new threats in the future.
“Maybe there are aspects that people didn’t value in the past and, 200, 300 years ago, selected against,” Peace says.
“But these days, actually, we do need them.” Scientists such as Peace, and detectives such as the team that brought the mystery apple to him, agree that retrieving those genetic resources is a vital task.
For one thing, apples are valuable.
They are the fruit Americans eat the most and one of the top commercial crops in the U.S., which grows more apples than any other country outside China.
Apple harvests are rising in volume all the time, but in genetic terms, the base of that towering, crunchy mountain is narrowing.
Although about 2,500 varieties exist in the U.S.
and roughly 100 are raised commercially, most of the market depends on just 15 of them.
And apples are under threat.
When small numbers of varieties are planted very widely, the crop becomes more vulnerable to diseases such as fire blight, powdery mildew and scab.
Having near-monocultures in the field means disease organisms don’t have to rely on the evolution of new mechanisms to overcome the diverse genetic protections collectively carried by many apple varieties; once they settle genetically on a strategy, they can attack.
And they do, very successfully.
A U.S.-wide estimate made more than 20 years ago put the annual cost of fire blight, a bacterial disease, in excess of $100 million.
Since then, outbreaks in various parts of the country have cost producers $16 million to $42 million at a time.
Changing weather patterns are compounding these effects by creating conditions that encourage the growth of bacteria and fungi or by pulling the seasons out of sync with apples’ growing patterns, forcing trees to bud earlier and making flowers and fruit more vulnerable to temperature shifts.
Washington State, the leading apple producer in the country, lost more than 2 percent of its crop to a heat wave in 2021.
Given these realities, retrieving genetics that have been lost to time and market contraction is crucial to apples’ survival.
Worldwide, scientists are working to associate specific DNA segments with qualities that apples will need under future conditions so that those traits can be bred back into the fruit; the genetic markers can then be used to confirm that the breeding was a success.
They are also looking for places where gene variants from long-surviving varieties have been retained in trees growing today; that persistence demonstrates how genetically useful those qualities have been.
Scientists carry out that work on apples grown by commercial breeders and held in agricultural-school collections—but they also rely on apple enthusiasts who bring them fruit for which names and provenance are unknown.
Of course, those amateur detectives aren’t hunting rare varieties primarily to serve science.
They are looking for lost trees for the charm of their names, the complexity of their histories and the love of apples themselves.
All these motivations were present in the self-assembled team—a historian, several apple hunters, two dedicated homeowners, and a crew of geneticists and breeders—that brought the Maine tree to Peace’s attention and hunted across continents and back through centuries to retrieve the lost apple’s name.
John Bunker was barely into his 20s when he realized apples might end up being his life’s work.
During a preteen summer visit, he imprinted on Maine like a duckling on a zookeeper, vowing to get back to the state when he was old enough to chart his own path.
He managed it by attending Colby College, a small school with a tradition of environmental programs.
It was the early 1970s and the peak of the back-to-the-land movement.
Bunker and some of his friends started driving around the middle of the state, looking for cheap property.
They found a plot—more than 100 acres—in the tiny town of Palermo.
“It was inexpensive, and I was young and wanted to live in the woods, and it seemed like the right thing,” Bunker says.
There were old apple trees nearby.
Bunker remembers his first reaction was, “Free food!” (and maybe booze, too; he had tried making cider at Colby).
But after a few years of homesteading, he became curious to know more.
He started knocking on doors, asking about past owners and what they grew—and, increasingly, about apples, which became more fascinating to him the more he learned.
A quick pause for biology.
Apples don’t self-pollinate the way that tomatoes and peppers do, fertilizing and germinating with no outside assistance.
Instead they cross-pollinate: pollen from one tree travels to a blossom on a second, thanks to a helpful bee that carries it.
This means each fruit has two parents, just like humans do—and, also as with humans, the parents don’t get reproduced identically.
Instead their offspring possess unpredictable combinations of traits—which, just as in humans, often aren’t fully identifiable until some number of years pass.
So if you want to precisely reproduce an apple variety you like, you don’t start it from a seed.
You clone it by grafting, which means cutting a short piece of twig, inserting it into the trunk or branch of a different “rootstock” tree and letting it grow up.
Generations of grafting can carry an apple variety unchanged into the future, and because trees are long-lived, grafted apple trees can survive after the people who valued and named them have died or moved away.
As Bunker learned about Maine apples, he began to understand how fragile that knowledge was, dependent on what people remembered about texture and taste and best use.
He took on the task of saving it, talking to old-timers, studying neglected trees on old farm properties, and hauling fruit home to examine and document.
“I had no knowledge at all,” Bunker says now, 50 years after he started.
“At a certain point after I exhausted all the information that was out there, I realized I was going to have to develop a system for identifying things.
Because I was getting into the ones that were more obscure, the local historic apples.” Over decades Bunker became the expert he had needed, teaching himself to classify apples by characteristics such as color, stem depth, bark appearance, and the pattern of seed cells in fruit sliced horizontally.
He founded a fruit-tree nursery named Fedco Trees and sold grafted descendants of trees to ensure their ongoing survival and give himself an income while he kept apple hunting.
And by excavating the history of abandoned apples, he created enthusiasm and demand for them.
When Bunker staged apple-identification events at agricultural fairs, people lined up to talk to him, clutching apples from family properties, and others asked him to come give talks.
One of the latter was Jeanne Russell, who lives with her husband, Ron, on Verona Island, a narrow sliver of land where the Penobscot River begins to open to the Atlantic.
In 2007 she invited Bunker to a gathering of the Bucksport, Me., garden club.
It took place at the Russells’ property, where they have lived since 1979; they have traced its past ownership in local records as far back as George Washington’s first secretary of war.
On its long sweep of lawn, which hangs above a river channel and below pines that house Bald Eagles, there are about two dozen apple trees, and some of them looked ancient.
After his talk, Bunker strolled the property with the Russells.
There were towering crabapples and thick-trunked trees that looked robust enough to bear fruit for years to come, as well as some tottering old specimens leaning sideways and barely hanging on to life.
Bunker sketched a rough map on the back of the manila folder he had carried his notes in and marked the ones he thought he recognized: Ben Davis, Yellow Bellflower, Tolman Sweet.
At one edge of the lawn, he recorded tree number 26 as “unknown”—a notable notation from someone as knowledgeable as him.
Later, Bunker would tuck the map away, promising himself to go back.
In fact, he wouldn’t return to the Russells’ farm for many years.
Farther east from the Russells, in the tourist town of Bar Harbor, a historian was exploring a different question: where Maine apples came from.
Todd Little-Siebold is a professor at the College of the Atlantic, a tiny school—it has 350 students and 33 faculty—that focuses on human ecology and hands-on learning.
He landed there as a new Ph.D.
specializing in colonial and 19th-century Guatemala and looked around for a project that would layer his knowledge of agriculture and economics onto the New England landscape.
He settled on apples.
Little-Siebold began taking his students to properties where old trees could make history visible for them.
“I introduce them to trees so that they ask the question, Who planted this tree? How could we find out?” he says.
“There are agricultural census records and deeds and all these different ways that we can reconstruct what was probably grown here and who grew it.” Trying to identify....
