I really was quite smitten with this pillow from Crate & Barrel, but I am allergic to feathers (and well, lets face it... for a seasonal pillow, its price was a bit steep!) SO... I figured out how to make something similar myself!
What you need:
12" pillow form
Red pillow cover: I used this tutorial to make my own using felt.
4 colors of green felt.
Green thread and needle
An object to trace circles (about an inch and a half)
2. Group them in fours and stitch them together.
3. Cut a triangle out of some green felt (in the shape of your tree).
4. Glue the circle bunches down, creating the pattern until it is full.
5. Glue a rectangle for the trunk onto the back of the tree (triangle).
6. Glue the entire thing onto your pillow and you are done!