Grandma March Day (or simply Baba Marta, ) is a holiday celebrated in Bulgaria, on the first of March. Martenitsa - usually in the form of a wrist band, woven by combining red and white colored threads - are worn on that day and through March, until a stork or a bloomed tree is seen, symbolizing warmer weather and well being. Older Bulgarians call it Birch Month, because it is around this time when birch trees start growing leaves and give sap. There's much folklore about Grandma March Day and the character of Baba Marta herself. The greeting exchanged on this day is Chestita Baba Marta (Честита Баба Марта – Happy Baba Marta, often shortened to ЧБМ on greetings cards).