The El Malpais National Monument is a volcanic landscape with geological features like lava flows, lava tube caves, sandstone bluffs and cinder cones, the most common type of volcano in the world, according to the National Park Service website. While rural residents of New Mexico frequently turn to cutting wood in the fall to help with heating during the winter, harvesting trees at El Malpais is illegal, the AP reported.

Alligator juniper trees grow extremely slowly. It can take up to 18 months for a seed to mature after pollination, while young trees grow about 0.6 inches per decade. This pace slows further as they get older, according to the AP.

The harvesting of these trees impacts the monument’s biodiversity, setting up the area for decades of recovery after the loss. Officials are not yet sure as to why the trees are being harvested or what they’re being used for, said Lisa Dittman, a spokeswoman for the monument.

For more reporting from the Associated Press, see below.

The initial illegal tree cutting discovery was reported in 2020. But park law enforcement monitoring the area and over the past year have reported additional trees cut down, with the latest incident happening in October.

Park employees are encouraging the public to submit any information that would help with the investigation to the National Park Service’s tip line.

The National Park Service recently cut brush and trimmed trees in the same area of the monument to prepare for a series of prescribed fires to restore fire into the ecosystem, targeting the buildup of vegetation that can lead to large catastrophic fires.

The park focuses on the protection of alligator junipers before thinning is done.

The largest of the southwestern junipers, the alligator juniper is found in western Texas, in parts of northwestern New Mexico and in north-central Arizona near Flagstaff. The species also extends into northern and central Mexico.

Research has shown that alligator junipers can live up to 500 years. The trees stop growing when moisture conditions are unfavorable but begin growing again with adequate moisture, a characteristic that enhances the species’ ability to survive in harsh, arid environments.

However, scientists have found that mortality can increase after several consecutive years of drought.