On the left is Sasa kurilensis, from the Kuril Islands between Japan and Russia. It's a shorter, groundcovering bamboo, that only gets about waist high. On the right, is Indocalamus tessellatus. It's a little over my head, so more than 6ft (2m) tall. The tall poles growing in the background (and a few within these clumps) are Phyllostachys angusta (Stone Bamboo).