"Since 1818, a particular chestnut tree has been used as the official "herald of the spring" in Geneva. The sautier (secretary of the Parliament of the Canton of Geneva) observes the tree and notes the day of arrival of the first bud. While this event has no practical effect, the sautier issues a formal press release and the local newspaper will usually mention the news.
As this is one of the world's oldest records of a plant's reaction to climatic conditions, researchers have been interested to note that the first bud appears earlier and earlier in the year. During the first century, many dates were in March or April. In recent years, it has usually been in mid-February and sometimes even earlier. In 2002, the first bud appeared unusually early, on 7 February, and then again on 29 December of the same year. The following year, which was one of the hottest years recorded in Europe, became a year with no bud. In 2008, the first bud also appeared very early, on 19 February."