Viscum album "Phoradendron leucarpum" is used in North America in lieu of the European "Viscum album".) According to an old Christmas custom, a man and a woman who meet under a hanging of mistletoe were obliged to kiss. The custom may be of Scandinavian origin. It was alluded to as common practice in 1808 and described in 1820 by American author Washington Irving in his "The Sketch Book of Geoffrey Crayon, Gent.": In Germany, the Christmas tradition is that people who kiss under mistletoe will have an enduring love or are bound to marry one another. Every year, the UK town of
Plant-for-the-Planet 1 million trees in each of their own countries. Plant-for-the-Planet promotes the view that each tree is a contribution towards environmental and climate protection. It also suggests that each tree planting is an action for social justice. The organisation says that it is most often the developing countries that suffer the most from the effects of climate change, despite the fact that they have most often done the least to cause it. Plant-for-the-Planet says it considers each tree to also be a symbol for climate justice. By the start of 2011, there were children participating in more than 93 countries.