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Trees in the desert are like oxygen at high altitude — scarce and precious.

During a recent spring tree giveaway sponsored by Nevada's Clark County, the team had a couple of hundred young trees ready and lined up for residents. All the trees disappeared within an hour.

Lulu Banks was eligible for two free trees. That's because her neighborhood in North Las Vegas is a designated "urban heat island" — a specific area that's hotter than other neighborhoods, in part because of lack of shade.

"I don't have any trees on my property," Banks said.

She knew exactly where she was going to plant the new trees: one close to her front window and another outside her bedroom. She hopes the shade will help lower her air conditioning bill in the summer.

Research has shown that trees can lower the temperature in the area around them significantly, by at least 10 degrees. And Las Vegas needs all the cooling it can get.

Climate change is driving up peak temperatures in cities across the country, and last summer, Las Vegas reached a record high of 120 degrees. Temperatures hit 100 degrees or higher for more than two months straight.

That summer heat contributed to more than 500 deaths, according to the Clark County Coroner's Office. Experts say heat-related deaths are likely undercounted across the country.

It prompted an increased focus on finding ways to help keep people safe from the heat.

In May, state lawmakers passed a bill requiring the state's biggest cities and counties to create heat mitigation plans by next summer; it was signed into law this month.

In Las Vegas, the city, county and nonprofits are all stepping up efforts to plant more trees and provide more shade — especially in the hottest neighborhoods.

Tackling "shade disparity" 

Across the U.S., studies show heat disproportionately affects lower-income neighborhoods because they tend to have older, less-energy-efficient homes and often have little tree canopy.

Ariel Choinard calls it "shade disparity."

Choinard leads the Southern Nevada Heat Resilience Lab, which studies how heat affects people and communities and then recommends data-based solutions. The lab was created in 2023 and is funded primarily by the National Oceanic and Atmospheric Administration, a federal agency.

In April, Choinard visited several urban heat island neighborhoods to demonstrate how the built environment can dramatically increase surface temperatures, and the significant difference trees can make.

A 2022 heat mapping project found that several areas, including East Las Vegas and North Las Vegas, can experience temperatures up to 11 degrees hotter than other parts of the region. Each of these neighborhoods is relatively poorer than other parts of Las Vegas.

"Folks here have to work harder and longer to afford to cool their homes," Choinard said. "And we know that people make really tough trade-offs when it's superhot."

That can mean choosing between keeping their homes at a safe and comfortable temperature and paying for groceries, or limiting medication.

Choinard pointed out a mature tree providing plenty of shade in a neighborhood without many others.

"It's this tree that's doing really great work here," she said.

On this day in April, it was 95 degrees out. But under the tree, it was much cooler. Choinard measured the temperature on the ground with an infrared thermometer: 87 degrees.

Trees help cool the air through a process known as transpiration cooling. Essentially, trees release water into the atmosphere from their leaves, cooling the air around them. Tree cover also provides shade, keeping sidewalks, roads and buildings from absorbing and trapping as much of the sun's heat.

At the Desert Inn Estates, a mobile home community with few trees in East Las Vegas, Choinard pointed the infrared thermometer at a picnic table sitting directly in the sun.

"130 degrees on a bench next to a table," she said, reading the device.

Asphalt can get even hotter: The asphalt parking space near the picnic table registered 144 degrees.

That's hot enough that Las Vegas has seen an increase in burns — among people and pets — from hot pavement during the summer.

Planting 2,000 trees a year

That's why the county, the city and nonprofits are all increasing efforts to plant more trees in the desert.

"Our 2050 goal is to plant 60,000 trees within the city of Las Vegas, and that breaks down to a little over 2,000 trees a year," said Brad Daseler, the city's urban forester.

Daseler is bringing in mostly nonnative plants that provide shade and are drought tolerant, like oak trees from northern Mexico and eucalyptus trees from Australia.

"Las Vegas is a pretty challenging environment for plant material in general because we do get so warm, but we also have the ability to freeze," Daseler said. "So finding trees that can survive in both of those climate extremes absolutely is a challenge."

And you can't just plant any tree in any place, Daseler says. There's nuance and strategy to what kind of trees are chosen for what areas.

Walking through the city tree nursery, he pointed out a young bur oak.

"Those would be trees that we would use more in our park spaces," he said. Other trees, like the Indian rosewood, can better withstand the harshness of being planted in a median, surrounded by asphalt and concrete, with a "high heat load."

The region is currently in a drought that the U.S. Drought Monitor has classified as "exceptional" — its severest category.

So there's a delicate balancing act, Daseler said, in maximizing both trees and water.

That's a constant challenge in the desert, says Choinard.

"There's always that question of, what is the highest use of a gallon of water?" she said. "But when we're talking about the long-term viability of our communities, I think a tree is a great thing to put water on."

Teaching the next generation

The tree-planting effort has also spread to some schools, which are starting garden clubs.

On a weekend this spring, students and parents gathered in the garden at Booker Elementary School. Students planted trees, fruits and vegetables in beds — each with its own letter, spelling out S-T-E-M (for science, technology, engineering and mathematics).

"Don't give plants too much water, but you need it to have some water so it can grow," said third-grader Donovan Pantoja.

His mom, Natalie Hernandez, said the project instills positive life lessons, and teaches kids to be environmentally conscious.

"And then they may teach their kids," she said. "And hopefully that trickles [down], to try to conserve and help the planet."

Yvette Fernandez is the Las Vegas-based regional reporter for the Mountain West News Bureau, a collaboration between Boise State Public Radio in Idaho, KANW in New Mexico, KUNC in Colorado, KUNR in Nevada, Nevada Public Radio, and Wyoming Public Media, with support from affiliate stations across the region.

Edited by Rachel Waldholz