Rawa-buki (Giant Japanese butterbur), is a registered Hokkaido Heritage plant found only in the town of Ashoro. This green broad-leaved plant grows in the fields of the Rawan river basin. Rawan-buki reaches its full size during the month of June and can grow to impressive heights of up to 3 or 4 meters. Standing under a Rawan-buki plant at its peak height can make even a full-grown adult look small in comparison.
Botanists who study Rawan-buki are not exactly sure what makes this species of butterbur grow so tall, but some think the phenomenon can be attributed to Ashoro's location in a basin valley, as well as the minerals in the Rawan River, which come from Lake Onneto.
Rawan-buki is an edible plant that is rich in fiber and healthy minerals, and it has been a staple of the local cuisine for centuries. The stems are eaten boiled or pickled, and also in curry and many other dishes. The leaves are ground into powder and used in teas, candies, and other processed foods, and are sometimes used to wrap other cooked food. Restaurants and hotels throughout the Ashoro area serve Rawan-buki in season.
In late June, people come from all over the area to designated Rawan-buki fields to harvest the plants. Participants take the Rawan-buki home in bundles for cooking and pickling. Dishes in which the plants are used include meat-stuffed Rawan-buki, Chinese-style Rawan salad, and minestrone soup.
If you are visiting out of season, stop by the Ashoro rest area Ashoro Ginga Hall 21 to sample and purchase boiled Rawan-buki, available year-round.
This English-language text was created by the Japan Tourism Agency.