According to the ancient legendary novel "Talking about the River", after Yang Di ascended the throne, he ordered the excavation of Tongji Canal. Yu Shiqi suggested planting willows on the embankment. Yang Di thought this suggestion was very good, so he ordered to plant willows on both sides of the newly opened Grand Canal and planted them himself. The imperial book gave Yangliu a surname and enjoyed the honor of sharing the same surname as the emperor. From then on, willow was called "willow".
Willow gets its name from the working method of willow head wood. Wood is still an indispensable material. In ancient times, tools were simple, so it was very difficult to cut thick trunks, while it was more convenient to cut branches two inches thick. Therefore, the wood used by ancestors was mainly branches two inches thick.
Therefore, the first wood operation of willow was formed, and the crown was cut off at a certain height to promote the germination of new branches, and the branches were cut off every few years for use. The result of the first wood operation is to keep the trunk so as to continue to use the branches. This is why the willow tree got its name. The word "Liu" has the same pronunciation as the word "Liu", which means "Liu", which means a tree that keeps its trunk for reuse.
References:
Baidu encyclopedia-willow