Bo Tree IV

The Buddha and assorted bodhisattvas sitting/standing under a bo tree (Ficus religiosa L.) on the grounds of Pha That Luong (see Tuk-tuk to Pha That Luong) outside of Vientiane, Laos. I am always curious as to whether the bo trees planted at pagodas throughout S.E. Asia are from cuttings taken from the mother tree at Bodh Gaya.

The sign in front of the bo tree at Pha That Luong cleared this up for me.  But are they really saying that the tree was planted on the site in 2500 BC, i.e. Siddhartha Gautama stood up after attaining enlightenment in 500 BC and the Supreme Patriarch of Laos immediately reached over and took a cutting?