With its verdant stands of old-growth cedar, hemlock and spruce, the Tongass National Forest is the largest intact temperate rainforest in the world. And at 16.7 million acres, covering most of Alaskas southern panhandle, its also the biggest national forest in the United States.

The Tongass thick overstory, made up of trees up to 800 years old, shades some of the worlds last healthy salmon streams. It hosts the largest known concentration of bald eagles and serves as a refuge for brown bears, which have declined in other areas of the country. And with these resources as the foundation of their ways of life, the forest has been home to the Tlingit, Haida and Tsimshian people for over 10,000 years.

All this is now under threat from the United States Forest Service under the Trump administration, which plans to remove protections from the forest by the fall to allow new roads to be built in pristine stretches that have never seen industrial development, and begin logging the Tongass old growth.

In response, the tribes that live there are making a last-ditch stand to protect their cultural homelands, engineering a new type of plan to recognize the relationship between the forest and the people whove lived in it for millennia. If successful, they could help lay the groundwork for other Indigenous efforts to protect functioning cultural landscapes all while helping the nation tackle climate change.

With its vast swaths of old growth, the Tongass stores more carbon than any other national forest, on par with the planets most dense terrestrial carbon sinks in Chile and Tasmania. Its the lungs of the country, according to Dominick DellaSala, chief scientist of the Geos Institute, a scientific organization working on climate solutions. DellaSala, who wrote a 2019 analysis on the forest, has called the Tongass Alaskas best and final shot at preparing for climate change.