This plant is native to Southeast Asia, and is thought to be a natural cross between Alocasia macrorrhizos and Colocasia esculenta (Taro). The stems are eaten as a vegetable in Southeast Asia, particularly Vietnam, and in Japan. The root corms of this species are fibrous and inedible, and the leaves are not particularly edible either.
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The photo to the left shows what the plant looks like. Some varieties can grow leaves up to 5 feet across. The stems are peeled and used as slices or short segments, mostly in soups. They have little flavor, but are valued for their foamy sponge-like texture and ability to hold a lot of the broth flavor. Photo by Dick Culbert distributed under license Creative Commons Attribution-ShareAlike v2.0 Generic.