Albizia Julibrissin is a beautiful ornamental tree that is popularly referred to as the "Silk Tree." Other synonyms for this plant species include Mimosa Tree, Persian Silk Tree, and Pink Siris. In China, where it is a native, the tree is called He Huan Pi, meaning "Collective Happiness Bark." It is also known as Nemu Tree in Korea, and sleeping tree in Japan because its leaves close up during the night. The pink and feathery flowers of the Albizia Julibrissin are loved by butterflies and bees, and the tree is used in herbal medicine to help calm the nerves and improve sleep quality.