Bamboo are a group of perennial evergreen (except for certain temperate species) plants in the true grass family Poaceae,subfamily Bambusoideae,tribe Bambuseae.Giant bamboos are the largest members of the grass family.In bamboo,wheat and other grasses,the internodal regions of the plant stem are hollow,but the vascular bundles,as seen in cross section,are scattered throughout the stem instead of in a cylindrical arrangement.