The small plant that is Ireland's national symbol is the shamrock. It is a three-leaved clover that represents the Holy Trinity in Christianity, which is the Father, Son, and Holy Spirit. The shamrock is also associated with St. Patrick, the patron saint of Ireland, who used the plant to explain the doctrine of the Holy Trinity to the Irish people. The shamrock is a beloved national symbol of Ireland and is worn proudly by the Irish on St. Patrick's Day, as well as on other occasions to showcase their Irish heritage.