The Idaho Volcanic Wasteland Where Plants & Wildlife Somehow Thrive in Solid Black Rock

Craters of the Moon, Idaho

Craters of the Moon spreads out like a black sea of lava rocks and volcanic cones in the state’s center. This national monument has the state’s most interesting hiking, with trails crossing ancient lava flows and dipping into caves that stay cold year-round.

Ice Caves Stay Frozen Throughout the Year

In several lava tubes at Craters of the Moon, chunks of ice remain frozen even when summer temperatures rise above 90°F outside. Winter snow and rain seep into these caves, freeze, and stay trapped in these naturally cold chambers.

Many animals, including foxes and bats, rely on this ice as a water source during dry spells. Crystal Ice Cave, the biggest ice cave in the area, stays below freezing all year, keeping its ice formations intact for hundreds of years.

How Native Americans Used and Traded Volcanic Glass

Local tribes valued the black volcanic glass called obsidian to make arrowheads, spear points, and cutting tools. Scientists have found tools made from this obsidian miles away from Craters of the Moon, showing how far the trading networks reached.

Each area of the preserve has obsidian with its own chemical makeup, which helps researchers track where ancient tribes traveled to trade. Today, several tribes still consider this a sacred place where their ancestors gathered this important resource.

The Way Special Flowers Grow in Volcanic Rock

When spring arrives, flowers like dwarf buckwheat, monkey flowers, and bitterroot bring splashes of color to the black rocks. These tough plants survive by growing roots deep through cracks in the rock to find water and food.

The plants stay small, usually under six inches tall, to handle strong winds and big temperature changes. These flowers create a colorful carpet of purple, yellow, and pink across the black rocks when they bloom in late May.

What Lives Inside the Dark Volcanic Caves

The long network of lava tubes is home to unique creatures like blind pseudoscorpions and special bacteria that thrive in the dark, rocky environment. These cave-dwellers have adapted to life in total darkness where the temperature stays at 43°F all year.

Researchers have found microorganisms here that don’t exist anywhere else on Earth. Most of these creatures have no color or eyes but have developed better ways to feel and sense their way through the dark caves.

Why These Volcanoes Could Still Be Active

Among all mainland U.S. volcanoes, these are the youngest, with the last eruption creating the Kings Bowl lava field just 2,100 years ago. Scientists think more eruptions could happen in the next thousand years because the volcanoes are dormant, not dead.

Visitors can see tall spatter cones, giant cinder cones, and long pressure ridges that look almost exactly as they did when the lava cooled. These features help scientists understand how volcanoes shaped this region.

The Size and Formation of Underground Lava Tunnels

Massive tunnels stretch miles under the ground, created when the top layer of lava hardened while hot liquid lava kept flowing underneath. These lava tubes are among the longest found in North America.

Inside these tunnels, you can see where 2,000°F lava left marks on the walls and dripped from the ceiling. The largest tunnel that people can visit, called Indian Tunnel, is 30 feet high, 50 feet wide, and about 800 feet long.

The Story of Trees Growing in Lava Fields

Some limber pine trees growing in the lava fields have lived here thousands of years ago. These hardy trees survive by growing roots up to 40 feet deep into cracks in the rock.

Strong winds have twisted these trees into unusual shapes, and they endure harsh temperatures. Each tree creates a sheltered spot where other types of plants can grow.

The Rare Blue Color in Broken Lava Rocks

When you break open certain lava rocks here, they show a surprising blue shine caused by special crystals in the quickly cooled rock. This blue color comes from minerals like magnetite and titanium in the rock.

These rocks formed when 1,800°F lava cooled rapidly. Scientists study this blue basalt to learn about the chemical makeup of ancient lava flows and how they cooled.

Where Animals Find Shelter in Winter

The rough landscape becomes an important winter home where animals stay warm in lava caves and rock cracks. Deer and elk use the high rock ridges to block cold winds.

Pronghorn antelope, sage grouse, and small mammals find protection here during freezing winter months. The dark rocks soak up sunlight, creating warm spots that can be a lot warmer than the surrounding area.

The Medicinal Plants That Grow in Volcanic Soil

Tribes traditionally gathered special types of sagebrush, yarrow, and purple sage that grew in the mineral-rich volcanic ground. These plants developed stronger healing properties because of the harsh growing conditions and high mineral content in the soil.

Scientists now study these plants for medicine, finding that some can fight bacteria and reduce swelling. Research shows these plants can help treat breathing problems and stomach issues, just as the tribes discovered long ago.

An Ideal Location for Viewing Stars

The preserve sits far from city lights, making it one of the darkest places left in the lower 48 states. The black lava rock absorbs light, letting visitors see thousands of stars on clear nights.

Scientists choose this spot for studying space because of its clean air at 5,900 feet elevation and usually clear skies. The black ground and bright stars above help show why people first called this place Craters of the Moon.