This technique, which is called daisugi, enables foresters to harvest wood much more quickly. The shoots can either be planted or harvested. Similar techniques can be found dating back to ancient Rome, which was called pollarding, and across Europe particularly in Britain where it's called coppicing.
The result is slender cedar that is both flexible and dense, making it the perfect choice for traditional wood roofs and beams. Daisugi cedar can be harvested every 20 years and with the base tree lasting hundreds of years, there's a lot of wood to be harvested from just one tree.
With such a demand and lack of space, foresters came up with an ingenious way to grow more wood using less land. This involves the heavy pruning of a mother cedar tree, which encourages tall, thin saplings to shoot upwards. Think of it as a bonsai on a large scale.