Filling with a texture

I'd like to select a section of an image and then fill it with a texture from another image. For instance, I could add bark texture from a tree to a section of a face. I'm not sure how to select a texture from one image and apply it to another. Thanks for your help.

open up bark image
select the section you want as pattern/texture
Click Edit..Define Pattern..
name it.
open other image,
select area you want to fill
add new layer
select fill bucket
set fill method to pattern
choose the bark pattern - should be last pattern.
click the new layer within selection - viola!