Need Help Identifying Mushrooms

The mushroom below is growing on a tree in my backyard. I know very little about botany in general and mushrooms in particular, so any help would be greatly appreciated.
First some scale:

Horizontal Mushroom Post 3

VerticalMushroom Post 4

Some close ups:

Mushroom Post 1

Mushroom Post 2

Finally, the mushroom below grew out of the same whole you see just beneath the current mushroom in the pictures above:

Mushroom 2

I doubt that there is a relationship between the two mushrooms (other than one of environment) since the first grew a couple of years ago.

%d bloggers like this: