On the Bush Fire scar, volunteers have begun restoring the desert, one saguaro at a time

In the middle of the Bush Fire burn scar northeast of Phoenix, Natural Restorations co-founder Justin Corey demonstrated how to plant a saguaro cactus. First thing to know: They're sharp.

Corey pointed to the green ties around the top of the 100 nursery cactuses lined up for the Save Our Saguaros replanting event. A knot signals the vulnerable side that needs to face north to avoid the sun.

“They’ll actually twist to try to reposition themselves to the right orientation,” Corey said. “We want to give them the best chance we can.”

A crowd of 95 volunteer planters listened and watched as Corey and Natural Restoration’s veteran staff showed them how to dig the hole, carefully place the one-foot tall saguaro and water the cactus and its neighboring protective plant.

Although the towering cactuses can withstand sweltering temperatures and fend off predators with their sharp spines, they are temperamental in their early years.

After thousands of saguaros were killed in the Tonto National Forest during the 2020 Bush Fire, Corey wanted to ensure all the cactuses for the annual event were planted correctly to have the best odds of survival.

Natural Restorations, an Arizona-based nonprofit that works with veterans to revitalize natural areas, estimated 80,000 saguaros died in the fire. The burned area has since struggled to recover.

Because the desert is not adapted to fire, repeated burns like the Bush Fire could transform the ecosystem from desert to grasslands.

Partnering with the U.S. Forest Service, the National Forest Foundation and several commercial partners, Natural Restorations hosted the fourth annual Save Our Saguaros event in the Bush burn scar as part of a larger restoration effort in the Tonto National Forest.

The Bush Fire burned over 200,000 acres in just a few weeks, but reintroducing saguaros to the area will take years. If saguaros take root after planting, they could take decades to reach the size of those burned in the fire.

“Everyone thinks the desert is this dead place, but really it’s this incredibly lively, hardy keystone ecosystem for the nation,” said Rebecca Veerman, a communication specialist for the U.S. Forest Service in the Tonto National Forest. “We need to make sure we can do everything we can to keep it.”

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How the Bush Fire spread quickly

On June 13, 2020, a driver pulled an overheating car into a patch of red brome, an invasive and highly flammable grass species. The car sparked, starting a fire near the intersection of Bush Highway and State Route 87, about 30 miles northeast of Phoenix.

During the previous winters, introduced grasses like red brome flourished with moderate temperatures and moist soil. The result was dense patches of vegetation that could act as surface fuels for a wildfire.

“Little fuels like that start really easily. You can throw a match down and you’re off to the races,” said Mary Lata, fire ecologist for the U.S. Forest Service. “That’s one of the reasons (the Bush Fire) was so disruptive and it spread so fast.”

The fire started on a southwestern slope, and as winds aligned with the incline, flames pushed further uphill, according to Lata. The flames leaned forward on the slope, burning closer to fuels and igniting them more quickly, exacerbating the spread.

The fire burned an average of 1,000 acres per hour for more than three days, Lata said, and scorched 214,000 acres in about a week.

While small patches of high-severity fire can benefit some ecosystems, a fire burning this intensely ravages the desert landscape.

“It was burning the desert in a way that the desert is just not adapted to,” Lata said.

The Bush Fire was fully contained on July 6, 2020, but not before damaging thousands of saguaros and native plants.

When fire burns across the bottom of saguaros, they usually do not recover well. They live off the water still inside for two or three years after a fire until they finally die, making replanting efforts essential to restoring saguaros in the burn area.

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Replanting cactuses can help restore an entire ecosystem

After observing the devastation from the Bush Fire, Justin and Nicole Corey — the husband and wife co-founders of Natural Restorations — were inspired to start their replanting program.

“I remember driving down Bush highway, and Justin and I both just started crying seeing the desert crisped and all the saguaros with their arms bent and everything,” Nicole Corey said. “We decided as we were driving that we really wanted to do something about it.”

The Coreys launched their program in November 2020 with a tree planting, then ventured into replanting saguaro and native plants in the Bush burn scar in May 2021.

Natural Restorations employs a team of post-9/11 veterans who lead volunteer trash and graffiti removal, planting events and help relocate saguaros from construction sites and private property for replanting.

During this year’s Save Our Saguaro event, the teams planted 100 cactuses, contributing to the 917 that Natural Restorations has planted since the start of the program. The Coreys recognize the importance of restoring other native plants as well, not just the saguaros iconic to the Sonoran Desert.

Volunteers also threw seed balls and planted other native species, hoping to restore fishbook cactuses, prickly pear, cholla, palo verde and mesquites.

“We’re trying to bring back the entire ecosystem, you can’t just bring back the saguaros. As we were planting in the spring, we would see pollinators coming in and checking them out as we got them in the ground,” Nicole Corey said. “So it’s really cool to see this ecosystem coming back.”

As more fires occur in the Tonto National Forest and across the state, organizers worry desert lands could transition to grasslands.

Invasive grasses like red brome and buffelgrass are adapted to fire, growing back stronger and outpacing native plants afterward.

It’s a vicious cycle: Grasses are dangerous fuels that rapidly spread wildfires, which kill desert plants and allow the grasses to dominate after the flames are extinguished while native species struggle to recover.

Although a saguaro can produce 20 to 40 million seeds in its lifetime, few seeds will sprout and even fewer will reach maturity.

“It could be a fool’s mission at this point. Climate change is happening and the landscape is changing,” said Veerman. “But some of us are stubborn and want to hold on to the saguaros because this is the only place they live and they are part of this important community for us and the wildlife.”

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How to plant a saguaro in the wild

Volunteers set out in groups of three, with one brave planter donning gloves to carry the nursery cactuses into the burn scar. They worked with a list of requirements to ensure each cactus had what it needs to survive.

“I was a little nervous at first, but it was fun,” said volunteer Deidre Knee. “How often can you say you got to plant a saguaro?”

For saguaros, location is key. The cactuses must be spaced at least 20 feet apart and paired with a nurse plant. Palo verde, ironwood or mesquites are often nurse plants for saguaros, protecting them from sunburn and extreme hot or cold temperatures.

Volunteers had to dig holes deep enough to cover the roots and ensure the correct side faced north before placing the cactuses.

“Everything in the desert is so harsh, I figured cactuses had to be pretty hardy," said Ana Walker, a volunteer for the event. "I didn’t realize how particular saguaros are."

Each side of a saguaro can withstand different amounts of sunlight. The west and south sides can endure more sunlight, while the east side can tolerate the morning sun. The north side is mostly shaded by the plant and should not be exposed to direct sunlight.

The saguaro will develop accordingly, producing dense spines on the sides that get the most sun to act as a natural sunblock.

Based on the spine density and the orientation the saguaros were growing before they were moved, the Natural Restorations team placed the green ties on each cactus to designate which side needed to face north. The ties will also help the team keep track of the saguaros planted over time.

After ensuring the cactus was oriented correctly, volunteers buried the roots and compacted the dirt. Natural Restorations distributed buckets of water to each group to give the cactuses a head start.

Natural Restorations and its partners will monitor the saguaros and continue watering about once a month during the first year.

Cactus survival is still iffy

Even if volunteers do everything correctly, the nursery saguaros may not survive.

“Planting saguaros out into habitat when they have been grown in cultivation is a challenge,” said Peter Breslin, a postdoctoral plant ecology researcher at the Desert Lab at Tumamoc Hill for the University of Arizona.

Nursery saguaros may not be as tough as those grown naturally. They can be more at risk to predators like javelina or packrats. Placement with a nurse plant is essential, and sometimes a burn area like the Bush scar may not have ample native vegetation to cover saguaros.

Natural Restorations is learning from past missteps: They changed planting locations after a batch of saguaros planted too close to the road struggled with excess dust from cars and OHVs. According to Breslin, restoration projects’ success rates provide valuable information for land managers.

If the replanted saguaros survive, it will take years for them to reach maturity.

Although growth rates vary depending on climate, precipitation and location, in the first eight years of life saguaros grow between 1 and 1.5 inches each year. They can grow to be 40 to 60 feet tall, but reaching that height can take a century or two.

Hayleigh Evans covers environmental issues for The Arizona Republic and azcentral. Send tips or questions to hayleigh.evans@arizonarepublic.com.

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This article originally appeared on Arizona Republic: Volunteers plant saguaro cactuses on Bush Fire burn scar near Phoenix