Bamboo shoots will emerge from the ground for a few inches and usually pause for about a week before continuing to shoot skyward. They are covered by a hard protective sheath at each node which is deciduous and falls away once the shoot fully extends outward. The sheath has several functions, one of which is to protect the new shoot as it extends its internodes. At this stage the new shoots have a high water content and are very soft. The diameter of the shoot at its base is the diameter that the new culm (cane) will have when fully mature and throughout its life. New shoots extend upward by extending its internodes similar to the way a telescoping antenna will extend by pulling on it. They are fully extended and hardened off in apx 6 weeks from emerging from the ground.