Every year, the tree is observed by the secretary of the Grand Council of Geneva (the local parliament), and the opening of the first leaf is recorded and announced publicly as indicating the beginning of the spring.

[3][4] In 1818, an official tree was chosen, and the sautier (the secretary of the Grand Council of Geneva, the Parliament of the Canton of Geneva) is in charge of regularly observing the tree, and of recording the date of the opening on an official register.

This event is then announced to the press and to the general public, indicating the beginning of the spring.

After its death in 1929, a third tree was chosen,[5] which died due to a fungus infection shortly after the last record, on 13 March 2015.

According to MeteoSwiss, the Swiss Federal Office of Meteorology and Climatology, global warming plays a role in this change, and so do other factors linked to the urban environment which increase the quantity of heat in the city.