I love this mushroom (Hypsizygus ulmarius) as I was able to identify it using a key on the Mushroom Expert web site. It also turns up every year at this time, growing on a Camperdown Elm tree near our Ash Woodlot. The mushrooms grow out of the cut off or broken ends of branches. The combination of pristine white, perfectly shaped mushrooms and gnarled tree branches makes an interesting photo.