Guadua is a Neotropical genus of thorny, clumping bamboo in the grass family, ranging from moderate to very large species. Physically, Guadua angustifolia is noted for being the largest Neotropical bamboo. The genus is similar to Bambusa and is sometimes included in that genus. Several animals are, to a various extent, associated with stands of Guadua bamboo, for example several species of seedeaters, and the Amazon and Atlantic Bamboo Rats.