Introduction to Millennium Immortal Grass: Also called horse rush, it is a perennial herb. This plant in Baoyun Temple was planted by Wang Zhihuan, a great poet of the Tang Dynasty. In the second year of Kaiyuan of Tang Dynasty, 26-year-old Wang Zhihuan was highly appreciated by Prime Minister Zhang Jiuling and was recommended to be the chief registrar of Hengshui County at that time. Before leaving, I saw a rush in front of the Prime Minister's house. I was moved by the scene, so I said to the Prime Minister: This grass is not greedy for fat and water, and will remain green for thousands of years. Since the wise prime minister trusts me, my students must be like this unscrupulous horse rush, not afraid of wind and frost in their official career for the country and the people, and always maintain the righteous character of a scholar. He also asked for a few trees to be planted in Hengshui, leaving a lasting legacy.