The veins on the leaves are from fussy cutting leaf printed fabric and being very... precise (my friends use a less flattering word) about placement. The dimensional effect is an artifact of the serrated applique process (and thanks to Pepita for the perfect segue.)
I've posted the serrated leaves tutorial in the Tutorials forum. Sorry it's later than planned; DH and I spent all weekend playing SWTOR and not attending to quilty stuff. Anyway, let me know if it's clear as mud or if you have any questions; the method is finicky but it gives good results.