Dr. Ayana Elizabeth Johnson: Welcome to How to Save a Planet. I'm Dr. Ayana Elizabeth Johnson.

Alex Blumberg: And I'm Alex Blumberg. This is the show where we talk about what we need to do to address climate change, and how to make those things happen.

Ayana: So Alex, as you may know, I spent five or so years living in California.

Alex: That's where you got your PhD, right?

Ayana: Yeah.

Alex: That's where you became the doctor you are.

Ayana: [laughs] Yes. At Scripps Institution of Oceanography at UCSD in San Diego. And one of the things that's really obvious when you're in California is that they take water very seriously.

Alex: Oh yeah. No, my in-laws and my sister live in California, and so it's very much like a topic of conversation much more so than here.

Ayana: Yeah. And it's not something we talk about very much in New York, right? But people in California, they're like, "It's very dry. Do you know how dry? When is it gonna rain?" Like, you know, all these kinds of things are just part of daily conversation.

Alex: Right.

Ayana: For comparison, Hilo, Hawaii, gets a little bit more than 10 feet of rain a year, whereas New York, where you and I are sitting, gets just under four feet of rain a year. And San Diego, in California, gets an average of about 10 inches of rain every year.

Alex: Oh. So way less than half of what New York is even getting.

Ayana: Way less. And that's in an average year. So California is no stranger to our droughts, right? The most recent one spanned from 2011 all the way through 2017. It was one of the driest periods in the state's history. And now California, along with much of the west, including parts of Oregon and Colorado, are already in another severe drought that experts say is shaping up to be unprecedentedly bad.

Alex: And how do they know that again?

Ayana: You know, measurements. [laughs] California gets about 90 percent of its rain and snow between the months of October and April. So when the rain—and even more importantly, the snow in the mountains doesn't come, the state's in trouble. And that's what happened this year.

Alex: And the snow is important because obviously, it snows in the mountains and then over the summer it melts and feeds all the rivers and streams and stuff.

Ayana: Yeah. Because snow melt would usually provide about a third of the state's water. So water for drinking, for agriculture. But this April, when the snowpack was supposed to be at its peak, it was only 59 percent of what the normal level would be.

Alex: God, that's crazy that a third of the state's water comes from melting snow.

Ayana: Yeah. We don't usually think of California as, like, a snowy place but, you know, the Sierra Nevada mountains.

Alex: Right.

Ayana: So yes, California is not all sunny Southern beaches.

Alex: Right.

Ayana: And this water shortage problem is not just an issue for people in California, because California is one of the major food-producing regions of the country.

Alex: Yeah, I remember reading somewhere that two-thirds of America's fruit and nuts come from California.

Ayana: Yeah.

Alex: Two-thirds of our fruit and nuts!

Ayana: Yeah. And in this area that's like basically the desert.

Alex: Right. And so to irrigate the desert, you need the snowmelt. You also need the groundwater, which is also super stressed right now, right? These things all feed into each other.

Ayana: Yep. And all these connections between climate and snow and rain and groundwater and agriculture, that's what we're gonna be talking about on the show today.

Alex: First, we'll take a quick trip through the history of how the United States became so dependent on food grown in the driest part of the country. And then we'll hear from people who found other ways of growing delicious food in these super dry parts of the country. And these methods use less water, and they may provide a path forward as climate change makes water out west even less predictable.

Ayana: The story we're sharing today is from our friends at the podcast Gastropod. And that show is hosted by Cynthia Graber and Nicola Twilley, and it's coming right up after the break.

Brad Lancaster: I woke up this morning. Wonderful sound of a light drizzling rain. I'll take anything at this point, as it's been so long since we've had rain. I'll go check the rain gauge. Uh, we got 0.17 of an inch. [laughs] But hey, that's better than nothing.

Nicola Twilley: I grew up in England where, as you might have heard, it rains a lot. So this kind of excitement over less than two-tenths of an inch of rainfall is foreign to me—or at least, it was foreign to me until I moved to Los Angeles.

Cynthia Graber: We had a pretty bad drought this summer in New England, but still we've had far more rain than you in LA or than Brad Lancaster in Tucson, Arizona. Makes sense since you both basically live in the desert.

Nicola: We do indeed. California and Arizona are part of what John Wesley Powell called The Arid Lands of America. John Wesley Powell, in case you're not familiar, was a one-armed Civil War hero who was the first white person to navigate the length of the Colorado River as part of his research into water and the American West.

Cynthia: In 1878, Powell argued that the arid lands of the west would not and should not and could not support conventional agriculture—the kind that on the East Coast relied on rainfall. It was just too dry. But the government and the settlers in the region totally ignored him. All that sun and land was just too tempting.

Nicola: And now, America grows most of its water-filled fruits and vegetables in this arid region. So how did we pull that off?

Cynthia: And was it worth it? What's happened to the region as a result?

Nicola: In a desert where water is more precious than land, should we be growing food at all? And if so, what?

Cynthia: What can we learn from people whose ancestors have been farming in that region for thousands of years? And could their experience over generations help farmers everywhere deal with a hotter, drier future?

Nicola: All that this episode, plus the intense flavors of the desert, including magic beans and shrivelled squash.

Cynthia: This episode was pitched by our fabulous Gastropod fellow Sonja Swanson, who lives in the desert of Las Vegas. And then we got a special, incredibly generous donation from Gastropod listener Tilia Jacobs, who was inspired by our "Digging for Victory" episode about urban agriculture. She told us she wanted to support reporting on a similarly hopeful and pragmatic topic.

Nicola: In addition to being a Gastropod fan and a super generous person, Tilia is a writer, and the author of two very gripping crime novels and a delightful middle-grade fantasy book. Her books are the perfect escape during these pandemic times—I laughed out loud!

Cynthia: Thanks Sonja, for the topic suggestion, and thank you so much to Tilia for your support of the show.

Nicola: So let's start by introducing you all to Ramona Button, of Ramona's American Indian Foods.

Ramona Button: I am a Pima living on the Pima Reservation here on Gila River. I am also half Tohono O'odham from south of here. They used to be known as the Papagos, but now they're called the Tohono O'odham. And the Pimas are Akimel O'odham, that's my other half. It means the River People.

Terry Button: And I'm Terry, Ramona's husband. Terry Button.

Nicola: Ramona and Terry are farmers. Their farm's about an hour southeast of Phoenix, on the way to Tucson. And the whole region is a desert. The Sonoran Desert includes Phoenix and Tucson and parts of California, and it stretches all the way over the border into Mexico.

Cynthia: Ramona's ancestors have been farming in the region for thousands of years, and her dad kept the tradition alive on the reservation where she grew up.

Ramona Button: My father did the wheat. He did the tepary beans, the brown, S-oam Bavi, and white tepary bean, which is the Stotoah Bavi. And he did squash, the garbanzos, watermelon, and the sugar cane and the black eyed peas, which is U'us Bavi. And chiles. Mostly he's known for his chiles.

Nicola: And those chiles are part of what brought Ramona and Terry together. Ramona had left the reservation to work as a nurse in South Dakota. Terry was there studying Lakota songs and culture.

Cynthia: Friends introduced them, and they told Ramona that Terry had picked up a few words of Pima as well. That's the language of Ramona's people in the Southwest. So Terry tried out his rudimentary Pima on her.

Ramona Button: And I said, "Well, you're saying it correctly, but your dialect, accent is different." And so it was a little bit hard to decipher, but I could understand him. So I said, "Well, hmm, maybe we're a good match. [laughs] And so it happened.

Terry Button: And then when I came, when I met Ramona, the first experience I had with Southwest cuisine was her dad's long green chiles. And they were so hot, they blistered my lips, they turned white. [laughs] She would send them to me in the mail when I went back to school, and I'd share them with some of my buddies, and nobody could eat them. [laughs] And her dad got pretty famous actually, in the local community. He's well known for—he used to sell small, brown paper lunch sacks with chiles. And he'd have mild and medium and hot. He would regulate the chile temperature by the way he irrigated his chiles. He wouldn't let anybody else water his plots.

Nicola: And not just because he was manipulating the fieriness of his chiles. It was because the water itself was so rare and so precious. There was never enough.

Gary Nabhan: A desert is a place full of things other than water. They get a bad rap because they have low rainfall, and it's as if they're empty spaces.

Cynthia: Gary Nabhan is a desert agricultural ecologist, and he's written more than a dozen books about agriculture and the desert and its foods. He lives an hour south of Tucson, also in the Sonoran Desert.

Gary Nabhan: Within a mile and a half of where I am sitting right now, we have evidence of 4,500 years of agriculture in the form of corn remains from an archaeological site. So I am in the valley in the United States with the oldest history of agriculture.

Terry Button: Yeah, well as far back and farther back than written history can go, the people were farming here when Padre Eusebio Kino, who was the first non-Indian person to come into this country, came here and visited the Pimas in 1675. They were irrigating their fields with diversions from the Gila River at that time.

Nicola: Even though it was a desert, the native people were growing corn, squash, chiles, and beans, as well as tobacco and cotton. They'd figured out how to make the most of the little water they had, and they'd bred crop varieties that thrived in the heat and the dry.

Cynthia: And then Padre Kino led the Spaniards to the region.

Terry Button: When he came, he introduced wheat from the Mediterranean. He introduced black-eyed peas from Northern Africa. He introduced garbanzo beans from the Middle East, and melons from Persia.

Cynthia: Turns out, these crops fit into the traditional agriculture of the region perfectly. The Pima and their neighbors could plant the Middle Eastern and African crops in the winter, after their corn and squash were done.

Nicola: Plus, those crops thrived without a lot of water. They fit into the kind of dryland agriculture the native people had already developed to conserve and make the most of what little rain they received.

Gary Nabhan: So that part of the Spanish colonialism was accepted among most tribes. As one Native American man I knew said, "I hate the white man, but I love his peaches." [laughs] And the point is that they saw a way to fit that into their seasonal calendar in ways that augmented food production.

Nicola: The Spanish were followed by other white settlers. Terry says the first in the mid-1800s, were Mormons fleeing persecution.

Terry Button: And they diverted the flows of the Gila and the Salt River for their irrigation purposes, without any regard for the fact that the Pimas were downstream. And they dried them up. And they dried them up to where there was a drought in the early 1900s, around 1890 to 1910, and the flows of the river were decimated, and the Pimas starved to death.

Cynthia: Then as the 1900s continued, the water situation got even worse. Gary told us that the first hit came in 1910, with wood-fired, steam-powered pumps that could get at the groundwater and use it for irrigation.

Gary Nabhan: Within 10 years of that, the gasoline-powered pump and the electric-powered pump came into circulation in the Southwest. And unbelievably to us now, given the kinds of climate change risks that we are facing to our food security, most farmers at that time simply abandoned all those water-conserving practices and said, "Bring on more water that will give us higher yields."

Nicola: At the same time, people started building dams—a lot of dams. Dams and reservoirs and tunnels and canals, all to divert the water from the few precious rivers in the Southwest to irrigate fields full of crops.

[ARCHIVAL CLIP: In many ways, the most valuable resource of the Arizona desert empire is water. Within the confines of this one state, engineers have constructed some of the finest dams of their types in the world.]

Cynthia: These amazing feats of engineering allowed for the creation of huge swaths of conventional agriculture: fields of greens and melons and alfalfa to feed dairy cows.

[ARCHIVAL CLIP: As a direct result of this tremendous supply of water for irrigation, Arizona is a bountiful, all-year vegetable and fruit basket. Arizona citrus: oranges, lemons, tangerines, limes and grapefruit are unsurpassed for quality and flavor.]

Nicola: A triumph over nature. But a triumph that pretty quickly turned into a tragedy. The rivers ran dry. All those grand dams? In dry years, their huge reservoirs often sit half empty. Years go by without the Colorado River ever reaching the sea.

Cynthia: When the water did run into the rivers and down to the sea, it also seeped underground into the aquifer. But over the past century, people have been pumping so much water out of that aquifer. Arizona is pumping twice as much water as the rain can replenish, and so the state is literally sinking.

Nicola: In fact, this groundwater pumping issue has been kind of an emergency in Arizona for a while. It was the justification for the largest and most expensive water project ever constructed in the US—the Central Arizona Project. That funnels water from the Colorado River onto Arizona fields. They started building it in 1973, they finished it 20 years later, and it cost nearly $5 billion. So you would think that water would be pretty expensive for farmers.

Cynthia: But you'd be wrong. Only about $1.5-billion has to be repaid at all. That's $3.5-billion for free right there. And on top of it, farmers don't have to pay any interest on that money over 50 years, and the repayments don't even go back to the federal government—they go to even more local water diversion projects that also help farmers.

Nicola: Water in the West is a giant taxpayer-supported giveaway. In 2006, economists estimated that the US spent nearly $1-billion each year on keeping farmers irrigating crops they would not otherwise be able to grow. The math is complicated, but the impact is huge. Farmers are getting millions of dollars' of water every year, it costs taxpayers a fortune, but it's almost free for them. And that's why farmers can afford to spray so much of it on their fields year round.

Gary Nabhan: So we had crops from more temperate or tropical regions brought into the desert, into a really artificial environment.

Cynthia: It's a really strange set up, if you think about it. Crops are just getting freely sprayed with water, as if it were raining in the East Coast, and the fields are green nearly year round. It's also super sunny and warm nearly year round.

Nicola: And these well-irrigated temperate region crops love it. Because it's so hot and dry, they don't get all the diseases they would back east, but they still get plenty of water. And it's so sunny that farmers can grow multiple harvests per year.

Cynthia: But as you can all imagine, this system is also seriously wasteful. Water evaporates as it's being sprayed on the fields, it evaporates as it's being moved around, it evaporates from the reservoirs. Dams and irrigation canals leak. And the crops that are planted in the region are really water-hungry ones. It shouldn't make sense, but since the water is so thoroughly subsidized, the deserts in Arizona and California and Oregon and Washington are exactly where a huge amount of our nation's crops are grown.

Nicola: In our apple episode, we told you that most of America's apples are grown in the desert in eastern Washington state. California alone produces two-thirds of America's fruit and nuts. And then together, California and Arizona produce almost all of America's leafy greens—lettuce and baby spinach and so on.

Cynthia: Cattle feed occupies the most farmland in Arizona. And it doesn't just feed local cows. Alfalfa even gets shipped to Saudi Arabia and China. Basically, Arizona water is being sent overseas, and it takes 2,000 gallons of water to get enough alfalfa to feed a cow to get a gallon of milk.

Gary Nabhan: And in 1976, we wrote the first alarm call for red alert. That instead of trying to remake the desert to fit certain crops by pampering them, we needed to aim for the crops that grew well in the desert, rather than remaking it into something else that took so much water and energy that it was not sustainable.

Cynthia: But nobody listened.

Gary Nabhan: Because there was still not enough incentive. Energy seemed limitless, water seemed limitless, and the majority of agronomists in our state universities ignored the call to really focus on a water-conserving agriculture.

Nicola: And so here we are. It's still totally unsustainable, but it's still going on. Gary sounded the alarm in the 1970s, but by now even conventional farmers know that there is not enough water anymore. But they're still planting almonds and alfalfa and greens because that's how they can make a living.

Cynthia: But the water problem has become so serious recently that farmers aren't going to be able to continue with business as usual for much longer.

[NEWS CLIP: Commissioner Brenda Berman of the US Bureau of Reclamation said that this drought is one of the worst in 1,200 years. At the public briefing, government agencies called for immediate action in order to conserve water and avoid shortages in the future.]

[NEWS CLIP: There is no ignoring it. The biggest source for water in the Southwest is on the verge of reaching a critically low level. And Arizona needs to act fast to conserve that Colorado River water feeding into Lake Mead.]

Cynthia: Ramona and Terry might have something useful to share with conventional farmers that could help conserve Arizona's water. They came back to Arizona from South Dakota, and they wanted to farm, and to make money, they too started working on fields of commodity crops like cattle feed and cotton.

Nicola: But Ramona also wanted to grow the foods she'd known as a kid.

Cynthia: One of which was a very special bean.

Ramona Button: We call it bafv. And bafv meant "bean." And that's the only way that I knew of it when I was growing up.

Nicola: Ramona is talking about the tepary bean.

Ramona Button: The white tepary bean, my first taste of it when I was a little girl was it had a sweetness to it. I'd say it tasted like somebody put butter in it. And the brown have the nutty, earthy flavor. When I'm cooking them, they smell like the first desert rain.

Cynthia: Ramona loved tepary beans, but when she and Terry started farming more than 40 years ago, they were hard to come by. People had started growing the common pinto beans instead; pintos grow well in irrigated fields.

Terry Button: Some of the elders would say, "We want you to grow the bafv, the beans, because we really want that and we can't find it any place."

Nicola: To be able to grow them, Terry needed to first find the beans—which was actually a little bit of a challenge.

Ramona Button: He said, "Well, where would these beans be?" And I said, "You know, my father was a bean saver—seed saver, rather." So we found them in an old trunk in a gallon jar. And so I said, "Well, you know what? These are my father's beans. Let's see if they're still good." And so we took them out, did a short garden, and found out that they germinated.

Cynthia: That was exciting, But it still took a lot of trial and error to figure out how to grow them. Now Ramona and Terry grow and sell three colors of tepary beans at Ramona Farms: white, brown, and black.

Brandy Button: I'm looking at our brown tepary beans, one of our exclusive staple crops here at Ramona Farms. It is the bean that was native to our peoples. And they are beautiful. They are like little, tiny river rocks, little pebbles.

Nicola: This is Brandy Button, one of Ramona and Terry's daughters. She's a chef, and she now works alongside her parents on the farm.

Cynthia: Sterling Johnson told us tepary beans are a big part of his identity, too.

Sterling Johnson: I'm born on the Tohono O'odham reservation, which just means—translates into "The desert." The desert people, more or less. Farming was a big—has always been a big part of the Tohono O'odham nation. In 1973, we became a recognized tribe. Before that, we were called the Papagos by the Spaniards. And we were called "bean eaters." And the beans that I'm talking about were the tepary beans.

Nicola: Sterling is the farm manager for the Ajo Center for Sustainable Agriculture, which he runs with his wife Nina Sajovec. Their place is a couple hours away from Ramona and Terry's farm, closer to the Mexican border.

Cynthia: Nina says tepary beans are special to people native to this region, not just because their ancestors ate them, but because the beans are so perfectly adapted to the desert.

Nina Sajovec: Tepary beans have the ability to close up their leaves and turn away from the 90-degree angle of the sun rays hitting them, which slows down the evaporation of their leaf surfaces. And they literally need two to three waterings, like really good monsoon soakings to survive. And they produce best under the stress too. They really are the desert miracle plants and the desert survivors.

Nicola: Part of how the tepary beans are able to thrive in the desert is, like Nina says, they can handle the heat. They can bloom and grow baby beans at temperatures where pintos will just give up.

Cynthia: And another reason tepary beans do so well in such an inhospitable environment is that, once they're planted, they grow downward fast.

Gary Nabhan: When we dug down into fields, the traditional fields, we found that the roots were eight feet down in the ground after two and a half months.

Cynthia: Back in the '80s, Gary was doing some desert agriculture research just near the Mexican border, in one of the driest places that has ever been farmed in North America. Both pinto beans and tepary beans had been planted there when he visited.

Gary Nabhan: Those beans were planted after a one-inch rain, and only received another quarter of an inch of rain over the growing season. And the tepary beans produced 1,200 pounds an acre, whereas pinto beans planted the same day shriveled up and died without their flowers ever making beans or fruit two months into the growing season. They were just—they couldn't take the heat.

Terry Button: They're very thrifty. They're very drought-tolerant. And they set early. And matter of fact, if you irrigate them too much, they don't do as well.

Nicola: Terry and Ramona and Brandy have already harvested their tepary beans for this season. They're cleaning and packaging them on the farm now. Brandy walked outside the office to show us the scene.

Brandy Button: Well, looking out from the east I see our beautiful mountains. We have the Sacaton Mountains off in the distance. And then you can see the green as you go down to the base of the landscape. And it's really beautiful because it's green against the desert, which is always nice.

Cynthia: Their green fields back up to beautiful pink-toned desert mountains, with the clear blue sky behind them as a dramatic backdrop. The colors are stark and super intense.

Nicola: Terry says there are beans up in the mountains too—they still grow wild in the hills all around.

Terry Button: There's different colors, varieties of beans, and we have focused on the white and the brown, and we have selected now the black. But there are different colors. There's pink, and there's mahogany, and there's tan with turquoise speckles.

Cynthia: Whatever the color, tepary beans are Brandy's favorite. She's worked as a professional chef, and she has some recommendations for how to think about cooking with them.

Brandy Button: It's basic, but it's not. [laughs] So you can just, you know, expand upon the flavors that each of the beans has distinctly: the brown have that earthy and nuttiness to them. For the brown teparies, I love to use them in, like, rice medleys and mixtures like that. My mom's traditional recipe is still our favorite where, you know, you add beef and you could add chiles and cumin and garlic. And the white beans have almost like a cheddar essence. They're very sweet and creamy and buttery. My favorite way to eat them is with butter, salt and pepper. Super, super simple.

Nicola: Even though the Button family love their tepary beans—they're so perfectly adapted for the desert, and they taste so delicious—they admit that the beans are definitely not a money-maker.

Terry Button: They also don't produce the huge yields that they can get in other dry bean production that people want when they're growing crops like pinto beans, growing 40 sacks to the acre. That's not gonna happen with teparies.

Cynthia: Part of the reason pintos still make financial sense in the desert is because water is subsidized. That said, teparies will grow when it's just too hot for pintos, whether or not the plants are irrigated. But it's still tough to make much money on these particular beans right now.

Nicola: Terry and Ramona actually still grow their commodity crops—cattle feed and cotton—to make a living. But they're committed to growing the tepary beans and other traditional desert crops, too.

Terry Button: We feel that the seeds are sacred, and they're a family tradition. They've been saved through Ramona's family over many, many years.

Cynthia: The beans are just one crop. Another one is the short, bushy desert corn called 60-day corn. Corn usually takes 70 to 100 days to grow, but this particular corn shoots up in less than two months to take advantage of the seasonal rain.

Nicola: Another special desert crop is the cushaw squash.

Nina Sajovec: So the Tohono O'odham squash or ha:l in O'odham, it's a type of a cushaw that you can find on both sides of the border.

Cynthia: They have dark and light green stripes. They're kind of veiny like a leaf. They'd make a great centerpiece. And there are cushaw squashes that grow in a bunch of different environments.

Gary Nabhan: In fact, Elvis Presley's baby food was green stripe squash mashed up by his mother and fed to him every day. That's why he was such a great rock star. He grew up on green striped cushaw baby food.

Nicola: Elvis was eating his cushaw in rural Mississippi, which is most definitely not a desert. But the cushaw that Nina and Sterling, and Ramona and Terry, and Gary all know and love has been bred and adapted to the Sonoran desert for centuries.

Nina Sajovec: And it's just amazing to see how zucchinis and butternut squash, and all of those things start withering with the sun of May and June and die off really quickly, despite plenty of irrigation. And the O'odham squash gets planted at that time. And it has a couple of very interesting chemical mechanisms for surviving this.

Nicola: The squash has evolved to only photosynthesize in the morning and evening, when the sun isn't so intense.

Cynthia: And then it also cuts off water to the leaves during the day, and shuts down pores in the leaves to stop water from evaporating.

Nina Sajovec: So the squash looks wilted. It literally wilts daily. And it revives really with the coolness of the evening, and then coolness of the night, and is back up again in the morning. And I remember the first year I grew it, I was like, "Oh no, something happened! It's all wrong!"

Cynthia: Luckily, that was exactly what was supposed to happen, and the squash was fine. Gary told us another way these cushaw squash plants survive is that they search for water everywhere the vine's growing, all along the ground.

Gary Nabhan: During the rainy season, once a vine gets going, it roots down at each node between the leaves. So a plant may be rooted in the ground at six or seven different places along the vine.

Nicola: These ingenious ways of surviving in the desert heat and dryness are all great, but you all know that the most important question is always: how does it taste?

Gary Nabhan: Well, I won't name names, but someone was doing an article on all the great-tasting squashes of the United States, and listed the cushaw squash in the lower rung saying it just doesn't stand up to butternuts. And I started laughing and the journalist said, "What's wrong?" And I said, "Well, that's because the squash pulp or meat is not the primary reason that people grow them in Mexico." First, it's the seeds, then it's the squash flowers. Third, it's the meat of the squash to feed their pigs or lambs or chickens. And the pulp of the squash was the added bonus, not the primary driver of growing that crop. Even the vine tendrils were eaten in salads. The seeds are the primary thing that they were grown for over centuries for mole pipian, it's a green moles made from squash and pumpkin seeds all over central Mexico.

Cynthia: Tepary beans and cushaw squashes are just a few of the many plants that are well adapted to agriculture in Arizona—and not all of them are native. We mentioned that the Spanish brought useful desert crops with them, and some of those are fruit trees like pomegranates and figs. Another benefit of these fruit trees is they provide shade for other crops. Shade helps keep the plants from burning and shriveling up in the sun, plus it helps prevent too much water from evaporating.

Nicola: And saving water, as you might have realized by now, is the name of the game in desert farming. But it's not just about which crops you grow—there's a whole set of very clever technologies that dry-land farmers have created to make the most out of a very very little.

Alex: Okay. Popping in here to take a quick break. When we return, some of the clever technologies farmers have created to make the most of small amounts of rain.

Ayana: This is a topic near and dear to our hearts, so we'll actually be doing a whole separate episode reported by Kendra on climate-smart ag soon. But for now, stick around to hear the rest of this story.

Ayana: Hey, earthlings. Welcome back. Now let's return to the Sonoran desert with Gastropod hosts Nicola Twilley and Cynthia Graber.

Erick Meza: All right, so we're gonna get started. We're gonna plant today some of the leafy greens for the fall and the winter season here in the Sonoran Desert.

Cynthia: Erick Meza is the farm education coordinator at Las Milpitas Community Farm in Tucson. And before he plants, he has to inspect what are called ollas.

Erick Meza: I'm gonna go ahead, take the olla off the ground and just do a visual inspectment. Once they get full with water, they should look like sweating the water out, not pouring any water out. So looks nice, good shape, no leaks, so I'm gonna go ahead and put it back into the ground again. I don't like to bury my ollas too deep, I just like to put them flush with the ground—just deep enough for them to be covered.

Nicola: "Olla" is the Spanish word for a pot, and that's what ollas are.

Cynthia: They're made of unglazed terracotta, and they come in a variety of sizes. They have a narrow opening at the top and a wide round bottom like a lightbulb.

Erick Meza: And this is a technique that is definitely not new. It's been around for at least over 4,000 years. It started in China and then Northern Africa. And what it is is you have this clay pot and you bury it, and you leave an opening on the top that is visible. And the rest of the pot, it is completely buried into the ground, so when you pour the water on the top, fill up your container or your clay pot on the bottom, it starts sweating the water out. And this is very efficient because when you start putting your plants around it, the plants will slowly start benefiting from this moisture that the clay pot puts out.

Nicola: No one knows exactly when ollas started being used as a way of irrigating crops in the Sonoran Desert. The Spanish learned about ollas from North Africa, so they brought that technique with them, but Indigenous people in the Southwest certainly made pottery before the Spaniards showed up.

Gary Nabhan: So some of these things, it's a little bit hard to untangle whether pottery was used for irrigation in native North America before the Spanish came, but the results are the same.

Cynthia: And those results can be fantastic.

Erick Meza: Yes, we honestly have observed that the amount of water that you save has been almost as high as 80 percent. In comparison with even a normal drip irrigation water system, it saves about up to 80 percent of the water. So that's huge.

Nicola: Olla irrigation is not suited to every crop. Erick and Gary told us that ollas are not actually great for beans or corn.

Erick Meza: What we have observed is that the plants that do the best around the ollas is the fibrous roots, things like tomatoes do good, peppers, cilantro. You can also grow root vegetables like carrots and beets.

Gary Nabhan: I have observed that vine crops like melons, cucumbers, watermelons, because you can have non-arable land that they sprawl out across, as long as you have good soil right around the pot.

Cynthia: Gary says the olla system can work on a larger scale, too.

Nicola: He told us about a similar system that's used in the Canary Islands to grow the grapes that go into some seriously good wines—plenty of grapes using just a tiny amount of rain.

Gary Nabhan: So this isn't things for marginal, poor, hippie organic gardeners. This is commercial farmers. I'm not disparaging my friends who are great old hippie gardeners and farmers. But this is done on a large scale. Yes, it can be scaled up. Yes, it can produce high-value crops that keep farmers prosperous.

Nicola: That said, an olla system just wouldn't work out in the field for cotton and alfalfa.

Erick Meza: I would love to see it working on an industrial scale. I think the way that agriculture is practiced nowadays, it is very different. And I think ollas might be limiting some of, for example, agriculture that we see nowadays, it requires the use of machinery into the soil, which if you have a bunch of clay pots buried into the ground, it might definitely be more like an obstacle.

Cynthia: Even if they don't necessarily fit into mechanized agriculture, the benefit of ollas is that they focus water exactly where the water is needed on a tiny scale. But in the desert, you have to think large-scale, too. When the water falls, it falls really quickly, really hard, and it's not always where you want it to be.

Sterling Johnson: And so when the rain comes, we get the rain that falls straight down, but it's not enough to water the fields. What really is enough to water the fields is what comes from the mountains 15, 20 miles away.

Nicola: Sterling is a dry-land farmer—that means he grows everything on his farm using just the water that comes from the sky. So when that kind of big downpour happens, he needs to capture every last drop before it races away.

Sterling Johnson: Yeah, you just had to know exactly where your water is coming from, because the reservation when it rains, it gets flooded. And sometimes one part will get it, another part will get it, and it just—always being ready. You know, having the fields ready, making sure things were in place for the water to come in.

Nicola: This whole system of channeling the runoff is called ak-chin.

Gary Nabhan: The ak-chin systems of the Tohono O'odham and Yaki people and several other Indigenous groups in the Sonoran Desert are really where there's dry streambeds 90 percent of the year. And on a few days each month, you get a big thunderstorm in the mountains above, and people get to work as soon as they see the storms are creating runoff in the mountains above them.

Cynthia: Like Sterling said, the mountains might be 15 miles away, but you only have about a half hour or an hour to get everything ready.

Gary Nabhan: And people are standing there ready, opening ditches to divert the water into different parts of their fields. And it was really one of the most remarkable agricultural systems of growing food with less water in the world.

Cynthia: To prepare, Sterling builds speed humps for the water that start miles away from his fields. These small, earthen hills and even fences out of branches don't just slow the water down, but they also direct it to just where he wants it to go so it can slowly soak into his crops. It's a technique that had been used in the region for thousands of years, but it had nearly been lost.

Nicola: Sterling learned by watching his elders. It took years.

Nina Sajovec: It's important to note this, too: it's a slow process. But, you know, we get one chance a year with the monsoon rains. But after a couple of years where you put that bundle of branches, the water starts carving its way, and you can soon start seeing, like, little channels. And as a good farmer, dryland farmer, you're not just harvesting your crops, you're harvesting your water and you're thinking ahead of that.

Nicola: The whole idea of ak-chin is capturing as much of the rainfall as possible, and the organic matter it brings with it as fertilizer, and getting it into the ground where you want it. Ak-chin is one method. Gary also uses smaller-scale methods called fredges, which are kind of woven living hedgerows on the edges of his field that help slow and direct water, as well as capture soil and leaves and animal poo.

Gary Nabhan: And there are similar systems in parts of Africa and Asia. And I don't really know their full geography there, but it's often in semi-arid lands where the amount of rain falling on a surface can be multiplied just enough through these micro-catchments to make a difference.

Cynthia: These systems do work. They also can work in combination with technology. Terry uses technology to help him create the right slope on the field to capture water and measure the amount of water in his soil, together with water-harvesting canals.

Nicola: Terry and Ramona, Gary, Erick, Nina and Sterling, what they're doing is traditional, but it's now really unusual. Like we keep saying, water is practically given away in the Southwest, thanks to huge taxpayer subsidies, and so the knowledge of how to capture runoff and make the most of it nearly disappeared.

Gary Nabhan: And by the time I came to study with these incredible farmers, masters of water, harvesting and growing crops in a hot, dry land, there was only 150 acres left in an area the size of Connecticut that used this ancient practice.

Cynthia: But until water costs what it should or subsidies change, or until climate change makes this even more of a pressing issue, it's gonna be hard to get more people on board with these labor-intensive water-gathering methods. They work, but they're not suited to intensive, large-scale monoculture.

Nicola: The other thing to bear in mind is that growing food in the desert? Traditionally, it wasn't a year-round activity.

Nina Sajovec: When we're thinking about the traditional O'odham food system, dryland farming provided a lot of food. But the other portion—and some anthropologists and elders estimate that even more than 50 percent came from hunting but also gathering. I'm a farmer, so I always focus on crops myself, but I think it's important to emphasize the almost lost art of gathering things like cholla buds or saguaro fruit harvest or even agave cactus or mesquite pods.

Nicola: Like Nina says, that's another tradition that was nearly lost, but that some people are picking up again today.

Cynthia: Brad Lancaster—he's the guy you heard earlier so excited about the rain—he's an expert in desert foraging and water management, and he loves to harvest quite thorny prickly pear cactus fruit from the streets in Tucson using tongs so he doesn't hurt himself.

Brad Lancaster: Okay, now let's go to another cactus. Ooh, this one is loaded. Nice!

Nicola: Brad has led an effort to plant these kinds of edible, desert-adapted native plants on medians and the sides of the street in Tucson, so everyone can share the bounty.

Brad Lancaster: Turns out, in the average neighborhood in Tucson, there's over a million gallons of rain falling on each one-mile length of neighborhood street. So that's enough rain falling on that one mile stretch of street to irrigate over 400 native food-bearing trees and many understory plants. So let's harvest some of that bounty. Now I'm gonna grab my tongs and pick up fruit, drop it in the bucket.

Cynthia: In Las Vegas, Sonja Swanson—our fellow who had the brilliant idea for this episode—she wandered to a nearby park to pick mesquite pods off a tree.

Sonja Swanson: It's sunset out here at the park, and it is time to pick some mesquite. So I'm gonna just come down here. And there are some very big thorns on this tree, so I'm gonna have to watch out. But the mesquite pods are nice and dry, which is good. Ah, wow, these mesquite spikes are very sharp. Ouch!

Nicola: If you drive out into the desert from where I live in LA, there are miles and miles of mesquite groves. This tree is everywhere in the desert Southwest. It thrives in the dry landscape; its roots go down as far as 600 feet, so that it can pump up water. It even shares that water, and provides shade to other desert plants.

Cynthia: Abe Sanchez is a member of the Chia Cafe Collective in LA, and he's involved in promoting the consumption of native foods.

Abe Sanchez: I mean, they are tearing it down to make charcoal, right? I mean, that's the big thing. Most people, whenever you talk about mesquite, right away, they know that mesquite barbecue. And when you have to tell them that, wait a minute, this is the fruit that the tree produces and so forth, whatever.

Cynthia: The fruit is the pod. It looks like a long kind of pinkish or yellowish pod of beans. You can see the shape of the beans inside. But when it comes to eating, people just grind the whole pod. They don't shell the beans.

Gary Nabhan: Mesquite pods have been used as a food for upwards of 8,000 years from Texas to Southern California and down halfway into Mexico. The pods can be ground into a pastry flour that's as good as carob flour or chestnut flour for pastry chefs, and a coarser flour that can be made into tortillas and breads and beers and other foods.

Nicola: Tortillas were the way Abe first tried mesquite flour.

Abe Sanchez: And I thought they were just, wow! I thought that was awesome. They were delicious.

Cynthia: Each year, Gary takes part in a community event where people bring all the mesquite pods they've foraged to an organization called the Borderlands Restoration Network. There, the pods get sorted, and then they're roasted in a cylindrical, hand-cranked drum.

Nicola: Then they hook up a grinder. It's mounted on a trailer, and the pods get fed into a metal cone and ground up.

Cynthia: The team then pours out the flour into a sifter, and then into bags so people can take their flour home with them.

Nicola: Before modern milling technology, Abe says desert people in the region would roast the pods in their cooking fires, and then grind them using an ironwood pestle and mortar, which would have been pretty back-breaking work.

Abe Sanchez: Traditionally, it was just mixed with a little—the flour was mixed with water and kind of made into like a gruel. Kind of like a little, you know, cream of wheat sort of thing, whatever. Also, it was made into, like, a little dough, and then woven into and kind of molded into little crackers, little cookies that were sun dried.

Cynthia: Abe says these traditional dishes wouldn't necessarily catch on today because, while mesquite flour smells like dates and ginger, it has a pretty strong woody, earthy flavor that isn't so appealing all on its own. Abe has other recommendations for cooking with it.

Abe Sanchez: So we would rub the chicken or rub the fish in mesquite flour. Works really, really good as a coating. When you bake it, it gives it a really nice coating, a nice little flavor to the meat. I make an awesome gingerbread. I used an awesome gingerbread recipe that I add mesquite flour to.

Nicola: We managed to buy some mesquite flour from a co-op in Arizona, as well as some other desert foraged foods—cholla buds, which are like the tiny, thistly flower buds of a cholla cactus, and prickly pear syrup.

Cynthia: We also got a few varieties of tepary beans from Ramona Farms, as well as a specialty product made from 60-day corn that's harvested, roasted over mesquite, and then dried and shucked by hand.

Nicola: We all made different things with our desert ingredients. Sonja covered breakfast with mesquite flour pancakes and prickly pear syrup.

Sonja Swanson: Okay, first pancake is going on. Okay, moment of truth. I'm gonna drizzle a little prickly pear syrup on. Wow, that's really nice. I feel like it's a tamarind flavor? Kind of a tart sweetness to it. And then, like, the cocoa you get when you first open the jar of cocoa. I'm a fan. I will be making this again.

Nicola: I took care of snacks with a mesquite and chia cookie, which I honestly thought was pretty gross. I like my cookies to taste like cookies, not health-food store sawdust-texture bran muffins. My husband Geoff, on the other hand, doesn't like cookies and does like bran muffins, so he was a fan.

Nicola: And this is your what number cookie?

Geoff: I plead the fifth. [laughs]

Cynthia: I made a whole desert feast for dinner one night. My partner Tim made a prickly pear syrup and mezcal cocktail. I rehydrated the corn and the beans and the green-and-magenta-colored cholla buds. I mixed mesquite with white and whole wheat flour for mesquite tortillas. And then we layered all the ingredients into it for a big desert taco. But first we tasted each ingredient individually.

Cynthia: And then we have these very interesting looking cholla buds, which you had some choice words about.

Tim: These cholla—you mean the hedgehog penises? They look exactly like a bunch of strange, you know, pieces cut off of weird hedgehogs. [laughs]

Cynthia: I don't know. I thought they looked like dethorned cactus flower buds—they were green and pink. But despite the fact that they didn't look so appetizing to Tim, he was willing to taste them.

Tim: It's pretty terrible. [laughs]

Cynthia: Oh really? Oh, I like it. To me, it tastes like an artichoke heart.

Nicola: Some of these foods feel like an acquired taste, for sure. The tepary beans, on the other hand, were a winner right out of the gate. Those were delicious. But the mesquite flour, I'm not sure a cookie was the way to go.

Cynthia: At first, the earthy flavor of the mesquite in the tortillas surprised me, but it did grow on me. I can imagine eating it again. That said, I don't think mesquite is going to necessarily become the next quinoa.

Nicola: What these foods do have going for them is a surprisingly high level of nutrients. Two tablespoons of those cholla buds have as much calcium as a glass of milk, which blew my mind. And of course, they don't need huge amounts of water to grow, which is kind of a big deal.

Cynthia: Foraging may not necessarily play a huge role in food security in the region, but special desert beans and corn and squash are delicious, and they can have an important role to play on the farm.

Nicola: They don't yield as much, so no one is gonna make a quick buck on them. But the tepary beans and that 60-day corn? They go from seed to harvest in, well, 60 days or so in the summer, when the sun and the heat will overwhelm other crops. And they really don't need more than the summer monsoon in terms of irrigation. Farmers can grow other crops for cash in the winter, and use these to fill in the summer months.

Cynthia: And desert crops may well become critical in areas outside of Arizona, too. Climate change means more intense, hotter summers with shorter periods of rain in a lot of farm regions.

Gary Nabhan: And it's gonna be between two-fifths and a half of all arable lands on the surface of this planet that will be facing conditions of 110 degrees or more.

Nicola: So the Sonoran Desert has a lot to teach regular farmers in an increasingly arid world. So do all the world's desert cultures.

Gary Nabhan: What we have to do is open up the incredible library of traditional knowledge about how to live in any desert, and look at that range of solutions that may come from the Sahara or the Gobi or the Rub' al Khali Empty Quarter in Saudi Arabia. Take those concepts—not exactly the same plants, but match them with the crop plants that are best adapted to our particular conditions. And so it's not a western science versus old ways dichotomy, it's both-and. We need to draw on both of those, because we are in deep manure right now with regard to the future of agriculture.

Nicola: Growers like Nina and Sterling and Ramona and Terry, water harvesters like Brad and Erick, they're showing us what to do.

Cynthia: But it's not enough. Gary says these changes need support to happen, and that means support from the government.

Gary Nabhan: Well, instead of doing dumber-than-nails climate change subsidy giveaways to alfalfa farmers who are just growing a deeper-rooted alfalfa of six to eight feet instead of two to three feet, why not give subsidies to farmers to grow mesquite that have a 500-foot depth in their roots? Our subsidy system is all geared to Iowa and Nebraska. And the senators and congressmen in the desert states have to say, "The deserts are the laboratory of the future, so we have to overhaul agricultural subsidies." I'm not against subsidies—libraries are subsidized public institutions—but we have to have subsidies for people who are thinking out of the box 40 or 50 years into the future, rather than just keeping up the status quo.

Nicola: At the start of the episode, we told you that most of our fruit and vegetables, and almost all of our lettuces and baby greens, are grown in the desert. So does that make sense? Should we grow lettuce in the desert?

Cynthia: Gary grows a number of different varieties of lettuce. He buys his seed from a breeder named Frank Morton, and he grows them under the shade of mesquite trees on his property.

Gary Nabhan: And when all my neighbors are done with their conventional lettuces, Frank's diversified lettuce varieties grow three to five weeks longer in the shade of mesquite than the lettuces of any of my neighbors. I love lettuce, I love salads. I also grow things like capers and pomegranates for vinegar and things like that for salad dressings. So I get my desert flavors in the salad, but I still love lettuce. And so it's how we grow them, not whether or not we should grow them that I think makes a difference.

Cynthia: Thanks so much to Sonja Swanson for pitching this episode, and for all her incredibly hard work producing it! And really huge, huge thanks to Tilia Jacobs who gave us a major donation to report this. Thank you for your generosity and support of the show.

Nicola: We have links to Tilia's books on our website: a couple of very gripping crime novels, and a delightful fantasy book for junior high-age readers. If you're looking for an escape or a gift, you should definitely check them out.

Cynthia: Thanks also to Ramona, Terry and Brandy Button of Ramona Farms, Sterling Johnson and Nina Sajovec of Ajo Center for Sustainable Agriculture.

Nicola: Huge thanks also to Brad Lancaster, water harvester extraordinaire, Erick Meza of Las Milpitas Community Farm and Abe Sanchez of the Chia Cafe Collective.

Cynthia: And of course, a huge thanks as well to one of the world's great experts on desert agriculture, Gary Nabhan. He's written many books, and his latest is called The Nature of Desert Nature. We'll have a link to his books and to everyone's work and to places for you to buy the desert products we've mentioned if you'd like to try them out. Gastropod.com.

Ayana: We hope you enjoyed that episode of Gastropod, hosted by Cynthia Graber and Nicola Twilley. And we'll be back with the new episode of How to Save a Planet next week.

Alex: In the meantime, please check out other episodes from Gastropod that touch on the intersection of climate and food, like their episode on apples. You can find those on Spotify, iTunes, or wherever you listen to your podcasts.