*ahem* I must say, this is a fucking great piece of art (god bless it, excuse my language, but really.. I couldn't even.. wow!) The lighting from the bag is excellent, and I am sooo curious about who the other pony is with "CJ" in the heart
This.. this just in 30 minutes. Either you're a time traveler (Just spit it out!) or just a damn good artist able to convey great emotions and a story in a single frame. I'm not telling the story, you can make your own. Truly heartwarming.
Looks like Cherry Jubilee has her initials carved into that tree along with her special somepony. The tree is probably the site of significant personal memories for her. The tree looks like it died, but now Zecora is using her alchemical skills to revive and heal it. Thus "saving memories" for Cherry Jubilee.
I guess she made her way through Dodge Junction before she came to Ponyville. And I guess this is the cherry tree Cherry Jubilee was meeting with her stallion under, if the heart with CJ+( ) is any evidence. Nicely shaded here, and a ncie glow effect as well. Really like the way you reflected the full spectrum of lighting on the tree. Love their expressions, too. Well done!