Episode Description

In 1909, the Mayor of Tokyo sent a gift of 2,000 prized cherry trees to Washington, D.C. But the iconic blossoms enjoyed each spring along the Tidal Basin are not from those trees. That’s because Flora Patterson, who was the Mycologist in Charge at the USDA, recognized the original saplings were infected, and the shipment was burned on the National Mall. In this episode, assistant producer Hilda Gitchell explores Flora’s lasting impact on the field of mycology, starting with a blight that killed off the American chestnut trees, and how she helped make the USDA’s National Fungus Collection the largest in the world.

Flora's Mushroom Ketchup Recipe
Thi​​s brief article and photograph of Patterson appeared in the Washington Star on December 9, 1917.
Staff of the Bureau of Plant Industry in front the USDA building, ca. 1900s. Flora Wambaugh Patterson is seated in the front row on the left. Beverly Galloway is standing to the right of the stairs. Courtesy of the National Archives.
Letter written by Flora W. Patterson about the plant pathogens found upon inspection of the Japanese cherry trees shipped from Japan to Seattle and then transported via railroad to Washington, DC
Specimen of a fungus on the Japanese cherry trees that is still unidentified to species. The specimen was collected and identified by Vera K. Charles, one of Patterson’s assistants, and is part of the collections at the U.S. National Fungus Collections
USDA plant pathologists and entomologists inspecting the first set of Japanese cherry trees that were found to be infected with exotic fungi and insects
The first set of Japanese cherry trees being burned on the mall following the discovery of potentially harmful plant pathogens and insects

All captions were written by Amy Rossman in her article about Flora.

Episode Transcript

Of Chestnuts, Cherry Trees, and Mushroom Catsup: Flora Patterson, the Woman who Kept Devastating Blights from U.S. Shores

KATIE HAFNER: Entire forests of American chestnut trees were being killed off as Flora Patterson raced to find the cause. 

DR. SANDRA ANAGNOSTAKIS: She was one of the foremost people worrying about inspection of imported commodities.

KATIE HAFNER: I'm Katie Hafner, and this is Lost Women of Science Shorts. It was the start of the 20th century and Flora Patterson had reason to worry.

She knew it was just a matter of time before another blight would strike. In the early 1900s, Flora Patterson, a widowed mother of two, threw herself into her work as a mycologist, a fungi specialist. She made it her mission to protect native species. Without her, we might not have the iconic cherry trees that grace the National Mall.

She pushed for laws to stop plants at the border so they could be checked for disease. And these inspections hinged on being able to identify invasive fungi precisely. And that's a challenge. Fungi species outnumber plant species by at least six to one. So, as Mycologist in Charge, Flora set out to expand the USDA’s fungal collection.

AMY ROSSMAN: It's like a library for fungi. 

KATIE HAFNER: That's Amy Rossman. She's one of the latest in a long line of female mycologists who've succeeded Flora Patterson at the USDA.

AMY ROSSMAN: So when people wanna know what a certain fungus is, they will ask for these specimens and compare what their unknown is with these known identified species.

KATIE HAFNER: Fungi are at once villains and heroes. They're good and they're evil. But mostly they're good. They're critical for life on Earth, sequestering carbon in the soil. Penicillin has saved countless lives, and of course there are so many industrial and culinary uses. Fungus puts the blue in blue cheese! But blighted American Chestnut trees, they had no defenses against a newly introduced fungus from overseas.

The towering chestnuts that dominated forests up and down the eastern seaboard were quickly wiped out, and this dark side of fungi? That was Flora Patterson's specialty. These days, mycology is having a bit of a moment. The number of mushroom foraging clubs in North America has grown by 30% over the past decade.

Amateur mushroom hunters are everywhere these days. Our assistant producer, Hilda Gitchell, met up with a group of hobbyists to see what has long made people like Flora Patterson tick.

HILDA GITCHELL: It's 10 o'clock on a chilly but sunny Saturday morning and I find myself tramping through the woods with a group of about 30 fungi enthusiasts, all heads down, on the hunt. It doesn't take long for our leader, Sigrid Jakob, to make a find.

SIGRID JAKOB: So what I've got here on this log is Hypholoma sublateritium, or called Brick Tops. It's a beautiful little wood decomposer that usually shows up in October, November. Um, and some people eat it. It's got a beautiful red, brick-color top and is yellow underneath.

HILDA GITCHELL: Sigrid Jakob is the president of the New York Mycological Society. 

HILDA GITCHELL: Wow, that's huge!

Suddenly a prize find.

MULTIPLE VOICES: Goodness. There is several dinners right there. May I smell it? This one’s even bigger.

HILDA GITCHELL: A huge colony of delectable hen of the woods mushrooms. Said to taste like chicken, there's enough for everyone to take some home.

MULTIPLE VOICES: Oh my God. There's more. Go get one. Go get one. And there's one, like, there's one like on this, behind the tree a little bit.

HILDA GITCHELL: Jakob leads these weekly walks year round, but her interest in mythology extends beyond the fungi themselves. She notes that for thousands of years, foraging for edibles and medicinals often fell to women - the knowledge of which ones to eat and which to avoid. Passed down, generation to generation.

SIGRID JAKOB: Women have been roaming the forests, looking for fungi, collecting, accumulating knowledge, cause it was always one of those permissible things for women to do.

And there was a strong batch of women in the 19th century. And as the profession became professionalized, as it, you know, entered the degree programs of the colleges and universities, women kind of got pushed out. So there are a few famous and very influential female mycologists, but they're not nearly as many as you would expect given how much of nature observation has always been done by women.

HILDA GITCHELL: One of the most influential female mycologists of the 19th century was Flora Patterson. She was born in 1847 and grew up in Columbus, Ohio, the daughter of a Methodist minister. She went to Ohio Wesleyan Female College, which in 1865 had listed Flora as an alum. This was just at the end of the Civil War, a time when only about one in every six college graduates was a woman.

Amy Rossman says that, beyond her bachelor's, Flora went on to earn at least one master's degree. Still, Flora's job prospects were slim. Four years after completing her studies, Flora married Edwin Patterson of Ripley, Ohio, and they settled in nearby Cincinnati where he was a steamboat pilot. He plied the Ohio River while she settled into family life, first giving birth to one son, and then another. But then, tragedy struck. Her husband was badly injured in a steamboat explosion.

AMY ROSSMAN: And she took care of him for 10 years and then he died and then she had to figure out what to do with her life and how to have, make a livelihood for her children.

HILDA GITCHELL: In that time, being widowed with two children meant becoming destitute, and there were few social safety nets. But Flora's brother was a professor at the University of Iowa. So she moved her family from Ohio to Iowa City and there at the university she enrolled in classes. 

With a name like Flora, she seemed destined for a master's in botany, the study of plants. Just as Flora finished her coursework, her brother took a post at an Ivy League school. Flora followed, and with sons now old enough to be sent to boarding school, she studied at Radcliffe College, the all women's sister school of Harvard. There, she found a job that let her reconnect with her childhood interest in mushrooms.

AMY ROSSMAN: She got a job at the Gray Herbarium, which included fungi at that time, preparing fungi and working on them, and that's where she got her background in mycology.

HILDA GITCHELL: Floras's title, assistant, at the Gray Herbarium in Cambridge, falls short in describing her growing expertise, according to Amy Rossman, who succeeded Flora a century later at USDA. Rossman, now retired, has researched Flora's life and work. She says that Flora, after three years of honing her skills, was able to not just preserve a specimen, but to identify it by sight.

AMY ROSSMAN: I imagine that she was looking at fungi, packaging fungi, getting the labels correct on the fungi, but the fact that she learned so much about fungi makes me think that she was actually doing some of the identification work.

HILDA GITCHELL: You'd think that such expertise would be in high demand, but you'd be wrong. Flora was an expert, but she was also a woman. So in 1895, 25 years before women got the right to vote, she made a move that Rossman says helped level the playing field. 

AMY ROSSMAN: She got her job through a civil service examination, and in some ways I think that the government using exams like that, that's how women got hired.

HILDA GITCHELL: The exam catapulted her to a job at the US Department of Agriculture, the USDA. But was she paid less than the men? 

AMY ROSSMAN: I don't think so, because you know in the government you have a GS rating and that's what you're paid because the exam was fair.

HILDA GITCHELL: Rossman says Flora's age may have helped.

AMY ROSSMAN: Flora was hired at the USDA when she was 48 years old. She had already seen a lot of life. And so she probably, you know, knew what was important and knew how she felt about things, and so she just went for it.

HILDA GITCHELL: By all accounts, Flora worked hard. Her skills were appreciated, even by those who resisted working alongside women. At the time, about 15% of USDA workers were women, but most of those women were secretaries or typists or in other clerical roles.

Despite the dearth of women, some men still complained that the place was being overrun. Rossman stumbled upon a letter while researching Flora's life. In it:

AMY ROSSMAN: Two prominent scientists then, saying how there were so many women scientists at the USDA, Flora Patterson was okay, but it had increased a dozen or more women.

Of course, there were about three, so.

HILDA GITCHELL: Flora immersed herself in her work, particularly the fungal collection. So in 1904, when a chestnut tree blight was quickly killing off entire forests, she was the go-to person to identify the source. 

AMY ROSSMAN: And at that time, chestnut trees were the dominant tree.

HILDA GITCHELL: So dominant that they towered over hardwood forests all along the eastern seaboard.

They were known as the redwoods of the East. The origin of the blight? Mycologist Dr. Sandra Anagnostakis is an expert on chestnut tree blight. She blames a fungus from Japan. 

DR. SANDRA ANAGNOSTAKIS: There was a flood of, of Japanese chestnuts, and that's almost certainly how the fungus got here.

HILDA GITCHELL: The fungal blight took hold pretty quietly. A forester at the Bronx Zoo was the first to sound the alarm when he noticed a dead American chestnut tree in the middle of summer. That mighty tree, it had been killed off by a tiny fungal infection that was barely perceptible at first. 

AMY ROSSMAN: It appears as these pretty little red spots, little, little fruiting bodies. They're about a millimeter across or even less, but they form clumps. So then you see these red things.

HILDA GITCHELL: The blight traveled quickly. By the time it was noticed at the Bronx Zoo, it had already stealthily spread as far west as Ohio. As it spread, Flora Patterson dug deep into the USDA’s fungal collection to figure out what was killing off those trees.

She's credited with being the first to narrow the cause to a fungus. 

DR. SANDRA ANAGNOSTAKIS: Here was this woman who had been one of the first people to look at the fungus and she had, uh, made a very reasonable identification. Flora Patterson understood at that time that the USDA fungal collection was going to be extremely valuable, but by that time I'm sure that she was very aware that there were many reports of chestnut trees dying suddenly. So I think she must have realized that the cat was already out of the bag and the fact that she could identify it was not going to be a whole lot of help.

HILDA GITCHELL: And she was right. Within 50 years, the towering American chestnut trees were gone. For Flora, the blight that had killed off the American chestnut was a warning.

It was clear to her that she was racing against the clock, that another blight could hit again, threatening not just native trees, but agriculture as well. 

DR. SANDRA ANAGNOSTAKIS: She was one of the foremost people worrying about inspection of imported commodities.

HILDA GITCHELL: At the time, international trade by steamboat was bringing in all kinds of new cargo from overseas.

Flora and her USDA colleagues were increasingly being asked to identify new pests arriving on plants.

DR. SANDRA ANAGNOSTAKIS: And there were many, many plants of various kinds coming in that she was responsible for looking at… the pineapple diseases and potato scab and things that she was seeing daily.

HILDA GITCHELL: Samples of these new fungal diseases were added to the USDA's collection by Flora and her team.

During Flora's 27 years at the USDA, the fungal collection grew to almost 115,000 specimens, over five times the size it was when she started working there. 800 of those specimens were added by Flora herself. Rossman says preparing an individual specimen is a lengthy and painstaking process.

AMY ROSSMAN: Say some fungus is on a, a leaf that comes through the ports and you identify it as something, or maybe you can't identify it, but you want others to know about its existence. 

Then you make a specimen of it, and if it's just a leaf, you can treat it like a pressed botanical specimen, just put it between newspaper and squash it down there. If it's a mushroom, you might wanna cut off a stipe and the cap and dry it. Then you have to make sure it gets disinfected some way, and then you put it in a packet, which is a, you know, just a little piece of paper.

In her day, she just maybe even hand write a label and put it on with all the information you have. You know, where did it come from? When was it collected? Who collected it? And then add it to the collections.

HILDA GITCHELL: Rossman says finding Flora Patterson's own handwriting on some of the specimen labels, a century later, was always thrilling.

When the 1904 chestnut blight hit, Flora was nearly a decade into her career at the USDA. She pressed hard for a plant quarantine, but got little traction. It would take another five years and another blight for the public to take notice.


KATIE HAFNER: So Katie here, uh, Hilda, when we left off, it must have been so discouraging for Flora Patterson. I mean, here she was.


KATIE HAFNER: She'd done her job as a mycologist.

HILDA GITCHELL: I mean, she had literally identified the fungus that was killing off the American chestnuts. She had done that work.

KATIE HAFNER: But it was too late to save those trees.

HILDA GITCHELL: Yeah. And then five years later, it almost happened again. It was Washington, D.C. And there was a gift from Japan, um, from the mayor of Tokyo to be planted all along the tidal basin, and it's those iconic cherry trees.

KATIE HAFNER: Whoa, whoa, whoa. Wait a minute. Wait. Cherry trees? Those trees are still there.


KATIE HAFNER: I mean, I know they're iconic.


KATIE HAFNER: Oh, wow. And they bloom every spring. I mean, they're on postcards. People come from all over the place. Like tourists. These crazy tourists.

HILDA GITCHELL: It’s not just tourists! My family goes every year to take those photos!

KATIE HAFNER: Oh! I'm sorry.

HILDA GITCHELL: Um, but those blooms, they're not the original trees. In 1909, the original batch of about 2000 saplings? They didn't work out.

Those trees traveled for weeks. By boat from Japan to Seattle, and then they came all the way across the country from Seattle to D.C., and by the time they got there, Flora and her team of inspectors were ready to greet them.


HILDA GITCHELL: And I talked with Amy Rossman about it. She says it must have been a shock when the trees were unloaded.

AMY ROSSMAN: They were just covered with fungi and insects. So three of the USDA scientists looked at those and identified some of the organisms that were there, and I imagined they were horrified. I would be. So they wrote a letter saying that this, this wasn't acceptable. And so they ended up being burned on the mall.

KATIE HAFNER: They were burned?

HILDA GITCHELL: Yeah. Yeah, in a bonfire. And you can see the photos of these trees stacked up in a giant pile, and they're right in front of the Washington Monument.

KATIE HAFNER: Oh, so this goodwill gift, this gift from Japan literally went up in flames for the world to see. But, but, so what about the trees that are there now?

HILDA GITCHELL: So those are from the second batch. Let's let mycologist Dr. Sandra Anagnostakis explain.

DR. SANDRA ANAGNOSTAKIS: After the destruction of the original trees, uh, another shipment was sent. And she checked them along with her colleagues and those trees were and those were the ones that were planted in Washington, D.C.

KATIE HAFNER: So that second batch, those are the trees that we know and love. Still, the spectacle of all this, this whole episode must have come as a real jolt to people.

HILDA GITCHELL: So those photos I mentioned, they were widely circulated, the photos of the burning trees, and there was public outcry. But the chestnut blight five years earlier, that was still fresh. So, the blight coupled with the cherry trees really captured the public's attention to the serious threat and the astronomical cost of invasive pests, and it launched a national discussion.

So Flora doubled down on her push for a federal policy. Here's Dr. Anagnostakis.

DR. SANDRA ANAGNOSTAKIS: She was able to write very convincingly that these things were coming into the country and had to be stopped. And it was because of her work, really the front line of, of convincing people, that the Plant Quarantine Act was finally passed in 1912.

HILDA GITCHELL: That 1912 Plant Quarantine Act? It mandated inspections of imports and it established border checks to stop infectious plants from coming in and spreading a plant pandemic.

KATIE HAFNER: Oh, so that's where that comes from. So that's all the forms you have to fill out when you're at the border…. do you have any plants, any so, and any fruit. Right? I mean, I have madly scrambled to eat all the apples in my bag just so that I won't get, like, arrested or something.

HILDA GITCHELL: Exactly, exactly. And it's not just those, that random fruit that you might have brought back, but you know, they make you check those boxes. Like, did I bring back any wheat or, you know, any seeds or anything?

KATIE HAFNER: Okay. But, okay, back to Flora

HILDA GITCHELL: Yeah. Yeah. So it's 1912. The Quarantine Act is now law, and Flora and her team are tapped to put a system in place. Her supervisor back then had nothing but praise for how this was done, and here's what he wrote:

MALE READER: When it became necessary to put into operation the Plant Quarantine Law of 1912, Mrs. Patterson and her assistance rendered material aid organizing and setting in motion the pathological inspection service, which has since grown in large proportion.

HILDA GITCHELL: Still, Mrs. Patterson and her assistance were nearly taken off the job. Two years after the 1912 Quarantine Act that she had championed, Flora was notified that she and her four employees, three of whom were women, the team that had won accolades for helping implement the new law, would be transferred to a department where they would no longer be inspecting imported plants.

Mycologist Rossman says it was presented as a cost cutting measure. Flora fought back with a strongly worded letter to her supervisors, reminding them that her group of inspectors, mostly women, had already prevented the spread of several potential diseases. She wrote,

FEMALE READER: It is significant that each fungus disease which has been called to public attention through the Department or by other workers had first been noted by the inspectors either directly or by means of correspondence. As instances of this nature may be mentioned English potato scab, silver scurf, chestnut blight disease and citrus canker, specimens of all of which had been secured by correspondence or requests for mycological assistance.

HILDA GITCHELL: Flora won that battle and she stayed on the job for seven more years, retiring at age 75. Mycologist Amy Rossman notes that she herself is among the most recent in a long line of women who have followed in Flora Patterson's footsteps as a lead mycologist at the USDA. For Dr. Anagnostakis, Flora's lasting legacy, though, is the fungal collection itself.

DR. SANDRA ANAGNOSTAKIS: The collection is absolutely invaluable, and I think that every mycologist in the country is in awe of the US National Fungal Collection.

HILDA GITCHELL: And to this day, the fungal collection at the USDA that she helped build? It's still the largest in the world. Flora Patterson never remarried, at least we found no evidence that she did. But she had a full career and she was living with one of her sons in New York City when she died in 1928, at the age of 80, 5 years after she retired. 

But you know what's odd?

KATIE HAFNER: What's odd?

HILDA GITCHELL: So despite all of those accomplishments - protecting entire plant species, beefing up the USDA collection and bringing women along as mycologists -  perhaps the thing that Flora Patterson was best known for back in her own time? It was recipes.


HILDA GITCHELL: Kind of a cookbook? So let's let Amy Rossman explain.

AMY ROSSMAN: Well, another thing she did, was write this popular article on common and edible mushrooms. So that was bestseller. It went into several printings.

HILDA GITCHELL: So of all of Flora’s scientific publications, and there were over a dozen, Amy Rossman says that this is the one that broke through to the general public.

KATIE HAFNER: Okay, I just wanna say here that this kind of pisses me off. I mean, she did all that valuable scientific work and she's best remembered for recipes?

HILDA GITCHELL: I know it's kind of crazy, but there is this one recipe, and when I talked to Amy Rossman, this is the one that she specifically mentioned. So this recipe, this was kind of at the end of this longer book about ways to use common mushrooms, what was edible, what wasn't, and it was credited to a few other people, but it was in this book that made Flora popular. 

KATIE HAFNER: I know we talked about, so it was the mushroom catsup, they called it catsup back then.


KATIE HAFNER: And that recipe totally kind of caught my imagination. So guess what I did? I, I made it. And I have to tell you, it took me a couple of days, and it's a weird thing. It calls for this ingredient, mushroom liquor. I thought, what's that?


KATIE HAFNER: It's actually just what you get by soaking the mushrooms in too much salt and…

HILDA GITCHELL: That was my biggest question, is how hard was it to get the ingredients? 

KATIE HAFNER: Well, the ingredients are, they're not hard to get, but it's sort of, they're called different stuff. And so then what I did, I guess I got maybe two ounces of liquid, and it's pretty liquidy. It's not all that ketchupy. Anyway, I put it in a little jar and I took it to a restaurant and I found some willing guinea pigs, most of them strangers to, uh, taste it and give me their feedback, but I had to warn them to hold back because just a little bit of this stuff goes a long way.

MULTIPLE VOICES: Okay. All right. Wow. It's like balsamic vinegar and ketchup put together. Yeah. Yeah. A little bit of mushroom after tastes. 

Oh, I actually, it reminds me of some Asian fusion, but that's sort of what rings a bell.

Are you sure it's ketchup? Because it's a little runny. And when I take a good whiff of it, it has like almost like a cinnamon or like cloves, maybe, even?

I don't taste mushrooms, which is a good thing cuz I don't like mushrooms.

Salty, fishy, oniony, fermented, kind of delicious and disgusting at the same time.

KATIE HAFNER: And if you'd like to give it a try, the mushroom ketchup recipe is on our website at lostwomenofscience.org, along with photos of the cherry tree bonfire, Patterson at her microscope, and so much more on the life of mycologist Flora Patterson.

You've been listening to Lost Women of Science Shorts. Thanks to my co-executive producer, Amy Scharf, senior producer Barbara Howard, production assistant Dominique Janee, our sound design engineer, D Peterschmidt. And Mike Fung, Jeff DelViscio, Paula Mangin, Elizabeth Younan, and Nora Mathison. This episode of Lost Women of Science Shorts has been funded in part by Schmidt Futures and by the Alfred P. Sloan Foundation.

Lost Women of Science is distributed by PRX and published in partnership with Scientific American. With assistant producer Hilda Gitchell, I'm Katie Hafner.

Katie Hafner

Host & Executive Producer

Katie Hafner was a longtime reporter for The New York Times, where she continues to be a frequent contributor. Katie is uniquely positioned to tell the stories of lost women of science. Not only does she bring a skilled hand to complex narratives, but she has been writing about women in STEM for nearly 30 years. She is the author of six books of non-fiction, and her first novel, The Boys, was published in July 2022 by Spiegel & Grau. Katie is also the host and executive producer of Our Mothers Ourselves, an interview podcast that celebrates extraordinary mothers.