Plan to preserve Joshua trees in California

When a renewable energy company began to destroy thousands of Joshua trees will be felled this month to make way for a massive solar farm. fueled the fire of resentment Among Mojave Desert residents and activists.

It was a public demonstration of the difficult dilemma facing conservationists fighting to preserve western Joshua trees. While the state is close to completing a draft conservation plan later this year, both climate change and solar projects are threatening the iconic trees’ desert habitat.

Climate scientists estimate that western Joshua trees will be able to survive on this basis alone until the end of the century. 10% To 25% of the land they now live on. And, as the Mojave and Colorado deserts continue to get hotter and drier, succulents will likely disappear almost entirely from Southern California – Also from Joshua Tree National Park,

The problem, experts say, is that while many species can move north and to higher elevations to escape rising temperatures, Joshua trees’ migration rate is much slower and they can’t keep up.

“Joshua trees are in this triple squeeze crisis,” said Christopher Smith, a biology professor at Willamette University who wrote one of the articles. 2023 paper Ways to strike a balance between solar development and Joshua tree preservation are being explored.

First, there’s climate change, Smith said. Then, there’s habitat loss due to urbanization and solar energy development. Finally, there’s increasingly common wildfires — which can get much bigger. erase it A large percentage of all living Joshua trees are destroyed in a single season.

“There are some places where, according to our census over the last 15 years, half the trees are dead,” Smith said.

after a Years of effort fail Western Joshua trees — a different species from their eastern counterparts — are set to be listed as endangered species in 2022, climate advocates and the state developed a law to preserve them. It also ordered the California Department of Fish and Wildlife to draft a science- and Native-American-backed conservation plan by the end of 2024, and impose a fee for removing Joshua trees — fees that would be used to fund conservation work.

For years, environmental groups Even more government agencies They have talked about moving the plants north to Oregon, so that in a hundred years the climate can be like that of Southern California. However, Joshua tree scientists say that transplanting this species is not that easy.

Among other obstacles to relocation, western Joshua trees face a hurdle of sorts. Single Species of Yucca Moth To pollinate them a unique, underground network of fungi which deliver nutrients to the trees. And scientists say there may be other species on which the plants depend, which they haven’t yet identified.

“I think most people would call it a Hail Mary pass,” Smith said of moving the plants a long distance. “In order to keep those (trees) as a long-term legacy, and not just for the zoo animals, you also need a functioning ecosystem.”

A Joshua tree in Juniper Hills is surrounded by the Bobcat Fire in 2020. With wildfires, climate change and habitat loss, Joshua trees in California are taking an increasing toll.

(Irfan Khan/Los Angeles Times)

Instead, the Department of Fish and Wildlife is taking a defensive stance and focusing on protecting the trees in select locations where they have the best chance of survival. Scientists are using models of future climate and maps of Joshua tree locations to identify areas within the trees’ current habitat that will still have an acceptable climate in a hundred years.

Many of these areas, called climate refuges, are small — which means scientists need extremely detailed maps to identify them. So, a team from the United States Geological Survey decided to create one. They studied nearly 1 million points on Google Earth across an area of ​​more than 50,000 square miles; then, they traveled more than 9,000 miles on paved and dirt roads during 30 site visits to verify that the trees they saw in satellite images were actually there.

The resulting data set, to release in December 2023The battle map is the battle cry for the state’s army of conservationists and scientists. They’re using it to identify refuges across the region — places they can deploy every tool in their arsenal to protect them from land developers, wildfires, heat waves and drought.

Measures could include removing flammable shrubs, planting new Joshua trees and working to preserve the entire ecosystem that depends on the trees, including moths and fungi. The state has also asked scientists for ideas on how to make trees more resilient.

Smith and his colleagues have sequenced the genomes of 300 Joshua trees, and the number is growing. With genetic maps like these, scientists have found that some populations of Joshua trees have genes that make them More resistant to hot and dry conditions,

Although no research has been published on the topic yet, according to Smith, there is preliminary evidence that roots adapted to better gather nutrients with fungi may be more capable of growing a new tree after a wildfire. This budding body of research could help the state introduce specific adaptations into the refuge — and generally work to keep genetic diversity high — essentially helping Joshua trees adapt faster to climate change.

However, the state’s focus on refuges doesn’t mean all other Joshua trees are doomed. The conservation act includes a tree rehabilitation program to move trees threatened by property development to these climate refuges. Wildlands ConservancyA nonprofit organization with dozens of protected areas in the western U.S. also wants to provide homes for relocated Joshua trees.

In 2006, the Sawtooth Complex fire destroyed the Joshua tree woodland within the conservancy’s 2,500-acre Pioneer Mountain Preserve, just northwest of Joshua Tree National Park. Tim Krantz, the group’s conservation director and emeritus professor of environmental studies at the University of Redlands, hopes to work with the state to rebuild that forest with transplanted Joshua trees.

Thousands of Joshua trees, such as this giant specimen estimated to be 150 to 200 years old, will be removed from the outskirts of Boron to make way for a massive solar energy array.

(Myang J. Chun / Los Angeles Times)

But removing an entire forest isn’t easy — or cheap. Conservationists need large hydraulic tree spades to dig up the plants and the soil around them. And when the tree is replanted in another location, caretakers must ensure the same side of the succulent is facing north and follow an intensive irrigation regime for the first few years after it’s moved.

“We’re hoping to eventually move hundreds of trees, and at that scale … ​​there’s a lot of monitoring and maintenance that goes on — a lot of boots on the ground,” said Krantz, who co-owned Landscaping Company Which often moved trees, including Joshua trees.

While Krantz hopes the Conservation Fund will be able to support this work, the fund — which funds all aspects of conservation — probably won’t have enough money to cover the entire costly process of relocating every tree threatened by property development.

Scientists, state officials and tribes are still debating the details of the conservation plan, but the Department of Fish and Wildlife is not ready to take action. One of the first steps in building an ecological fortress around Joshua Tree refugia is to make sure the state either owns the land or has permission to do conservation work there. In 2023, the department completed its first land acquisition with a non-profit organization Native American Land Preservation,

The site is not only a potential haven for Joshua trees, but also a cultural site for the Kawaiisu Tribe. Now, the land will be permanently protected by the tribes and the conservancy, having voluntarily entered into a legally binding conservation easement facilitated by the state.

“It really reassures everybody that the land is being set aside for its intended purposes forever — because it gets recorded,” said Nicole Johnson, an attorney who works with tribes and a board member of the Native American Lands Conservancy.

A desert ecologist hikes through the Joshua Tree Study Site in Joshua Tree National Park in May 2023.

(Gina Ferrazzi / Los Angeles Times)

In addition to partnering with the Native American Land Conservancy, the state is working with more than a dozen native tribes to co-manage the conservation plan and combine science with traditional ecological knowledge. However, building relationships with tribal governments takes time, said Drew Kaiser, a senior environmental scientist with the California Department of Fish and Wildlife who is coordinating the conservation plan’s development. The co-management aspect of the plan is still in its early stages.

The department is also working with a solar project in the Mojave Desert, near Boron, to preserve more than 80,000 acres of Joshua tree habitat. According to the companyState requires firm to pay Over $1.3 million To compensate for the loss, the company has decided to deposit 4,700 trees in the conservation fund. However, the company is not planning to plant any of the 4,700 trees at another place.

For Smith, this is the reality of the situation the state finds itself in. “A lot of species are going to go extinct, and a lot of populations of Joshua trees … are going to be lost. The situation we’re in right now is to stop the bleeding and decide which ones to save.”