I bought this Stampin' Up stamp set a few weeks ago and these cards are my first 'play' with it.
I prefer the lighter brown for the main body of the tree, I think. The scalloped mats are made using Tonic Studio dies and the holey-edged mat (can't think of it's proper name!) is from Little B. The sentiment stamp is from Stamping All Day.
There are some lovely examples of this stamp set online, done in autumn shades, I think I'll be trying those next :-)