Climate Change in Joshua Tree National Park, California

Joshua trees in front of snowy mountain in Joshua Tree National Park, California
Joshua Tree National Park

Joshua Tree National Park is named after the Joshua trees (Yucca brevifolia) native to the Mojave Desert. Originally declared a National Monument in 1936, Joshua Tree National Park was re-designated as a National Park in 1994.

Joshua Tree National Park includes parts of two deserts, each an ecosystem whose characteristics are determined primarily by elevation: the higher Mojave Desert and the lower Colorado Desert. The Joshua tree can be found in the Mojave Desert area of the national park (and outside the park).

The Joshua tree (Yucca brevifolia) is a member of the Agave family, but don’t confuse the Joshua tree with the Mojave yucca (Yucca schidigera). This close relative can be distinguished by its longer, wider leaves and fibrous threads curling along leaf margins. The Joshua tree is a monocot in the subgroup of flowering plants that also includes grasses and orchids. It grows between 1.5-3 inches per year.

The average lifespan of a Joshua Tree is about 150 years old, but a few of the largest Joshua trees may be much older. They average about 40 feet, but can grow up to 70 feet.

 

Fire in the Mojave Desert (2020)

Watch this 4-minute video on the Dome Fire and its impact on the Mojave Desert and Joshua tress.

In the Mojave desert, fires provide an opportunity for invasive plants to take root, which in turn leads to larger and more frequent fires. In Joshua Tree National Park, this cycle has resulted in fires of 5,000, 6,000, and 13,000 acres over the past few decades, and increasing acres of invasive grasses. The Dome Fire, in Mojave National Preserve, burned 43,000 acres and over a million Joshua trees in summer 2020. (Source: National Park Services)

How does Climate Change affect Joshua Tree National Park?

Higher temperatures and longer drought periods are threatening Joshua trees and they may not be many left by the end of the century based on forecasting models.

If you look around Joshua Tree National Park you see an abundance of Joshua trees, but what you most likely do not see is that these trees are mature and there is a lack of younger trees. In large areas of the national park Joshua trees have not reproduced its population.

There are a few small areas, called microrefugia, where conditions are better for Joshua tree’s survival: lower temperatures than the surrounding areas and more precipitation. In these areas more young Joshua trees can be found. According to Dr Cameron Barrows, ecologist and researcher on biodiversity conservation at UC Riverside’s Palm Desert Center,  about 20% of Joshua Tree National Park might be saved for Joshua trees, if we can protect these microrefugia and reduce carbon emissions. (Source: Climate Stewardship by Adina Merenlender with Brendan Buhler, 2021)

More information on Climate Change in the Southwest by the National Park Service.

What can we do to reduce effects of climate change?

As stewards of our nature, we should always follow the 7 Principles of Leave No Trace when we visit our national parks. Use refillable water bottles and pack your lunch in reusable containers to eliminate waste.

Volunteer with a national park, state park, or other nature preserves in the area where you live. Not only will you learn about your local ecosystem, but you will most likely make new friends. To volunteer with Joshua Tree National Park, please visit Joshua Tree National Park Volunteer Opportunities.

For broader national impact on climate change, get involved in civic action. Write to your local representatives to demand action on climate change and vote for politicians who make climate change a priority.

 

Enjoy our nature & help protect it.