By Max Graham for Grist.
Broadcast version by Alex Gonzalez for Arizona News Connection reporting for the Solutions Journalism Network-Public News Service Collaboration

Below the red-tile roofs of the Catalina Foothills, an affluent area on the north end of Tucson, Arizona, lies a blanket of desert green: spiky cacti, sword-shaped yucca leaves, and the spindly limbs of palo verde and mesquite trees. Head south into the city, and the vegetation thins. Trees are especially scarce on the south side of town, where shops and schools and housing complexes sprawl across a land encrusted in concrete. 

On hot summer days, you don’t just see but feel the difference. Tucson’s shadeless neighborhoods, which are predominantly low-income and Latino, soak up the heat. They swelter at summer temperatures that eclipse the city average by 8 degrees Fahrenheit and the Catalina Foothills by 12 degrees. That disparity can be deadly in a city that experienced 40 straight days above 100 degrees last year — heat that’s sure to get worse with climate change. 

The good news is there’s a simple way to cool things down: Plant trees. “You’re easily 10 degrees cooler stepping under the shade of a tree,” said Brad Lancaster, an urban forester in Tucson. “It’s dramatically cooler.”

A movement is underway to populate the city’s street corners and vacant lots with groves of trees. Tucson’s city government, which has pledged to plant 1 million trees by 2030, recently got $5 million from the Biden administration to spur the effort — a portion of the $1 billion that the U.S. Forest Service committed last fall to urban and small-scale forestry projects across the United States, aiming to make communities more resilient to climate change and extreme heat. 

But in Tucson and many other cities, tree-planting initiatives can tackle a lot more than scorching temperatures. What if Tucson’s million new trees — and the rest of the country’s — didn’t just keep sidewalks cool? What if they helped feed people, too?

That’s what Brandon Merchant hopes will happen on the shadeless south side of Tucson, a city where about one-fifth of the population lives more than a mile from a grocery store. He’s working on a project to plant velvet mesquite trees that thrive in the dry Sonoran Desert and have been used for centuries as a food source. The mesquite trees’ seed pods can be ground into a sweet, protein-rich flour used to make bread, cookies, and pancakes. Merchant, who works at the Community Food Bank of Southern Arizona, sees cultivating mesquite around the city and surrounding areas as an opportunity to ease both heat and hunger. The outcome could be a network of “food forests,” community spaces where volunteers tend fruit trees and other edible plants for neighbors to forage. 

“Thinking about the root causes of hunger and the root causes of health issues, there are all these things that tie together: lack of green spaces, lack of biodiversity,” Merchant said. (The food bank received half a million dollars from the Biden administration through the Inflation Reduction Act.)

Merchant’s initiative fits into a national trend of combining forestry — and Forest Service funding — with efforts to feed people. Volunteers, school teachers, and urban farmers in cities across the country are planting fruit and nut trees, berry bushes, and other edible plants in public spaces to create shade, provide access to green space, and supply neighbors with free and healthy food. These food forests, forest gardens, and edible parks have sprouted up at churches, schools, empty lots, and street corners in numerous cities, including Boston, Philadelphia, Atlanta, Seattle, and Miami. 

“It’s definitely growing in popularity,” said Cara Rockwell, who researches agroforestry and sustainable food systems at Florida International University. “Food security is one of the huge benefits.” 

There are also numerous environmental benefits: Trees improve air quality, suck carbon from the atmosphere, and create habitat for wildlife, said Mikaela Schmitt-Harsh, an urban forestry expert at James Madison University in Virginia. “I think food forests are gaining popularity alongside other urban green space efforts, community gardens, green rooftops,” she added. “All of those efforts, I think, are moving us in a positive direction.”

Researchers say food forests are unlikely to produce enough food to feed everyone in need of it. But Schmitt-Harsh said they could help supplement diets, especially in neighborhoods that are far from grocery stores. “A lot has to go into the planning of where the food forest is, when the fruits are harvestable, and whether the harvestable fruits are equitably distributed.”

She pointed to the Philadelphia Orchard Project as an emblem of success. That nonprofit has partnered with schools, churches, public recreation centers, and urban farms to oversee some 68 community orchards across the city. Their network of orchards and food forests generated more than 11,000 pounds of fresh produce last year, according to Phil Forsyth, co-executive director of the nonprofit.

Some of the sites in Philadelphia have only three or four trees. Others have over 100, said Kim Jordan, the organization’s other executive director. “We’re doing a variety of fruit and nut trees, berry bushes and vines, pollinator plants, ground cover, perennial vegetables — a whole range of things,” Jordan said. 

The community food bank in Tucson started its project in 2021, when it bought six shade huts to shelter saplings. Each hut can house dozens of baby trees, which are grown in bags and irrigated until they become sturdy enough to be planted in the ground. Over the past three years, Merchant has partnered with a high school, a community farm, and the Tohono O’odham tribal nation to nurse, plant, and maintain the trees. So far they’ve only put a few dozen saplings in the ground, and Merchant aims to ramp up efforts with a few hundred more plantings this year. His initial goal, which he described as “lofty and ambitious,” is to plant 20,000 trees by 2030.

The food bank is also organizing workshops on growing, pruning, and harvesting, as well as courses on cooking with mesquite flour. And they’ve hosted community events, where people bring seed pods to pound into flour — a process that requires a big hammer mill that isn’t easy to use on your own, Merchant said. Those events feature a mesquite-pancake cook-off, using the fresh flour.

Merchant is drawing on a model of tree-planting that Lancaster, the urban forester, has been pioneering for 30 years in a downtown neighborhood called Dunbar Spring. That area was once as barren as much of southern Tucson, but a group of volunteers led by Lancaster — who started planting velvet mesquite and other native trees in 1996 — has built up an impressive canopy. Over three decades, neighborhood foresters have transformed Dunbar Spring’s bald curbsides into lush forests of mesquite, hackberry, cholla and prickly pear cactus, and more — all plants that have edible parts.

“There are over 400 native food plants in the Sonoran Desert, so we tapped into that,” Lancaster said. “That’s what we focused our planting on.” 

The Dunbar Spring food forest is now what Lancaster calls a “living pantry.” He told Grist that up to a quarter of the food he eats — and half of what he feeds his Nigerian dwarf goats — is harvested from plants in the neighborhood’s forest. “Those percentages could be much more if I were putting more time into the harvests.” The more than 1,700 trees and shrubs planted by Lancaster’s group have also stored a ton of water — a precious commodity in the Sonoran Desert — by slurping up an estimated 1 million gallons of rainwater that otherwise would have flowed off the pavement into storm drains.

Another well-established food forest skirts the Old West Church in Boston, where volunteers have spent a decade transforming a city lawn into a grove of apple, pear, and cherry trees hovering over vegetable, pollinator, and herb gardens. Their produce — ranging from tomatoes and eggplants to winter melons — gets donated to Women’s Lunch Place, a local shelter for women without permanent housing, according to Karen Spiller, a professor of sustainable food systems at the University of New Hampshire and a member of Old West Church who helps with the project. 

“It’s open for harvest at any time,” Spiller said. “It’s not, ‘Leave a dollar, and pick an apple.’ You can pick your apple, and eat your apple.”

Merchant wants to apply the same ethic in Tucson: mesquite pods for all to pick — and free pancakes after a day staying cool in the shade.


Max Graham wrote this article for Grist.


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Nevada scored high for its well-funded conservation programs and for the state's commitment to public land protections.

A new report by The Center for Western Priorities evaluated eight Western states within three categories - land protection and access, responsible energy development, and land use and planning for growth.

The Center's Policy Director Rachael Hamby said Nevada has done a good job of becoming an "assertive leader" as it relates to public land protection and conservation - especially with 67% of the state being made up of public lands, according to the Bureau of Land Management.

She added that Nevada was also the first state Legislature to endorse the global 30X30 Initiative, which is a plan to conserve 30% of nature by 2030 - to avoid what Hamby called a "biodiversity crisis."

"They've made progress towards that goal too, opening a couple new state parks," said Hamby, "and again this is a state doesn't always have as much of a surface area to work with - and this shows that is OK. You can be a conservation leader with your state-level policies in place for the lands that you do manage on behalf of Nevadans."

Hamby said the Silver State has also taken action to protect wildlife, including what she calls a "strong habitat framework" that is a direct result of an executive order signed in 2021 by former Gov. Steve Sisolak.

Nevada also passed a bill in 2021 that requires developers to consult with the Department of Wildlife on their subdivision plans and assess how projects will impact wildlife connectivity.

Nevada didn't have a legislative session in 2024, but it will have one in 2025.

Hamby said despite Nevada being in a good spot, there are still areas for improvement, such as responsible energy development.

Despite Nevada not being a major oil-producing or natural-gas producing state, it currently has no statewide setback requirements for oil and gas wells or any laws or rules on the books to reduce methane emissions.

Hamby said each state can celebrate its wins, but must also get to work where they're lagging.

"So hopefully the scorecard can help with identifying some area for growth in each state," said Hamby, "as policymakers are looking for ideas of what they might be able to do to advance conservation goals."

Hamby added that the positive economic implications of a transition to a clean energy economy will become even more evident in years to come.

Since the passage of The Clean Energy Plan in 2022, Nevada has seen more than 20,000 new jobs across the state.

When the Champlain Towers South collapsed in Surfside in 2021 taking 98 lives, it sent shock waves across South Florida. The tragedy has left lingering questions about the safety of coastal high-rises and whether the ground beneath them is as solid as once thought.

A new study by scientists from the University of Miami uncovered a troubling pattern: 35 buildings along the coastline from Miami Beach to Sunny Isles Beach are sinking, some at rates of up to eight centimeters in the past seven years.

Farzaneh Aziz Zanjani, a postdoctoral researcher at Washington University in St. Louis and the study's lead author, called the findings significant.

"We saw a correlation between the start of the subsidence and the nearby construction activities and we also found some correlation between the geology," Aziz Zanjani explained. "As we move from Sunny Isles to Miami Beach, the amount of subsidence is less."

Using satellite-based technology, the team tracked subtle ground movements which are otherwise invisible. Sunny Isles Beach, known for its luxury high-rises, showed the most dramatic rates of subsidence. The researchers believe the southern Florida geology with softer sandy layers within the limestone may be a factor.

For longtime residents, the study is unsettling. The idea some buildings may be sinking in a region already grappling with rising seas and stronger storms adds concerns about the future. Aziz Zanjani cautioned against jumping to conclusions.

"It doesn't necessarily mean that these buildings are unsafe," Aziz Zanjani pointed out. "This is beyond the scope of the study we had. It just shows that there is something happening under these buildings and it's related to geology and a lot more factors that we don't understand, and we need to do more research."

The research was motivated by the Surfside collapse but scientists found no evidence subsidence contributed to the tragedy. Still, Aziz Zanjani emphasized the study highlights the need for transparency and better monitoring of structural stability across the region. Aziz Zanjani's paper is open-access to the public.


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The Iowa Department of Natural Resources is training operators of Concentrated Animal Feeding Operations on the safest ways to apply manure to their fields and what to do if a spill happens. It is part of the state's effort to help reduce accidents and protect the environment.

Iowa produces about 50 million tons of manure every year or enough to fertilize roughly 17% of the state's cropland.

Jeff Prier, senior environmental specialist for the Iowa DNR, said the state is teaching commercial and smaller operators how to apply it safely by following a required manure management plan.

"When they go out to do their application, they need to comply with any separation distances to residence, church, business, school, public use area, water sources," Prier outlined. "Dependent on their application method."

Manure from Concentrated Animal Feeding Operations is known to pollute air and groundwater when it is not properly applied. Commercial operators said they are looking for more environmentally friendly ways to operate while trying to meet consumer demand for high quality meat. The deadline to apply for the DNR training is next week.

The DNR charges commercial operators $225 for a manure application permit and $175 for smaller operators. Prier noted it is a small price to avoid fines of between $3,000 and $5,000 for applying fertilizer without state certification.

"When they hear the numbers, they tend to open their eyes pretty big and think that's a pretty big number," Prier observed. "But the best reason is being in compliance with the rules and regulations and knowing what to do if there is a spill."

Prier, who has been overseeing training for 26 years, added given the amount of manure spread on Iowa farms every year, the number of spills is relatively small.


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