Chojabaru Visitor Center was added to Your Favorites!
Aso-Kuju NP, Oita
Claim this place to tell your story your way.
Tadewara Marsh formed about 6,300 years ago, when volcanic ash and debris blocked the Shiramizu River. Today, rain and mountain springs keep this volcano-made basin wet.
Tadewara’s 38 hectares need human care: locals revived the long-interrupted spring burn, prepare firebreaks, then light fires at opposite ends so the flames meet and run out of fuel.
After the spring burn, Tadewara can look almost completely black—then yellow violets begin blooming against the charred ground. The fire clears old growth and helps keep the wetland from turning into woodland.
In August and September, look for the globe thistle’s vivid blue, ball-shaped bloom. It only looks like one flower: the “ball” is a cluster of many tiny flowers, on a plant with roots in continental Asia.
Tadewara Marsh covers 38 hectares; neighboring Bogatsuru Marsh covers 53. Together, they make the 91-hectare Kuju Bogatsuru-Tadewara Ramsar site, registered as internationally important in 2005.
More than 100 kinds of wildflowers bloom at Tadewara from spring to autumn, drawing butterflies and other insects. Those insects, in turn, help feed small birds such as the chestnut-eared bunting.
“Chojabara” is tied to the local Asahi Chōja, or “Morning Millionaire,” legend. Tourism pioneer Kumahachi Aburaya named the area “Chojagahara” when a tent hotel opened here; the name later shortened to today’s form.
The surrounding Iida Plateau’s grasses once served as more than pasture and winter cattle feed: a 1721 Tano village record lists making traditional straw rain capes as a source of income.
An 1846 village chronicle recounts grassland fires spreading and destroying nearby Shiratori Shrine in 1604 and again in 1715. The burns helped maintain pasture and thatch grass—but were never risk-free.
Inside the center, a satellite image of Aso-Kuju National Park is displayed at 1:8,000 scale across the floor. You can stand on the landscape itself while getting your bearings around Kuju.
