The tree's the thing..
Tom (the cat) is all over the pan background in this scene. As a matter of fact, it was virtually impossible to completely eliminate him. The animators never revealed the entire bike. Similiarly, the red gift box on the far right is animated on a cel, and while it bounces around a bit, it never moves out of the way completely.
So... here's the entire pan shot, re-created with Tom and the red box remaining!