If you open the odf it tells you what texture the leaves need. For example, if we open:
yav_prop_leaftree.odf
It tells us other odfs are attached. We're concerned with the two yav_prop_leafpatch odfs
It's looking for yav_leaf
.tga. The other leafpatch is looking for yav_leaf2
.tga. Anyways, that the gist of how it works. Ya'll probably knew that, but I figured I'd share for those who didn't.