In the traditional lunar calendar, May 23 is known as Chikusui-Jitsu, which literally means the "day for bamboo drunk." This day was thought to be the best for replanting bamboo, as the existing bamboo would be too intoxicated to realize what was happening. There are sometimes Saké drinking rituals connected with this holiday, generally using Bamboo Saké.
One form of such is Hachiku-zake, Henon bamboo Saké. To make it, you sliced a young henon in two at one of the nodes and then drill a small hole at the node. Some Saké is then poured into the hole and it will be left to sit there for a couple days. Sugar and other items from the bamboo will permeate the Saké, creating a different taste, and this Saké is also thought to prolong one's life.
Another form is Chikureki-shu, bamboo oil Saké, where the bamboo is similarly cut and filled with Saké. But, this one is then placed over a heat source and warmed, allowing certain elements to seep into Saké, such as bamboo oil, chlorophyll, and vitamin K. It too was thought to have medicinal purposes and recent research has discovered that bamboo oil can be effective in cancer prevention.
Have you ever tried bamboo Saké?