People who have passed by the Amelia Square site in downtown Fredericksburg of late might have wondered why there is a small tree atop two of the four-story town-houses now under construction. Turns out it's part of a long-standing tradition in the construction industry called "topping out" that celebrates the last beam being placed atop a building. A tree or branch is often placed on the top beam. The tradition is common throughout Europe. Two of the owners of the homes being built have spent ample time in Germany and asked for the topping-out ceremony to be performed at their units, said Patrick Gay, one of the builders who is developing the complex.