Thanks, everyone!

Great ideas -- though it didn't sound like anyone's actually done much of this decoupage with leaves thing, quite a few approaches were forwarded. Now, I guess it's experimentation time.

F.Y.I., from my first two tries, it became apparent that any moisture or oilyness in the leaf was going to cause failure (should've known that). My second attempt used a light coat of spray mount on the back surface of the leaf, then a rub-down onto the surface using a mylar shield. This got the leaf down almost complely flat -- then I gooped over it with System Three, and again, used mylar to press out bubbles and "form" the epoxy over the remaining surface undulations. This worked pretty well, except that when I pulled the mylar away (while somewhere between "green" and fully cured), a few light spots appeared in the epoxy -- my guess was again, some delamination of the thin epoxy film. Guess maybe one more try might involve letting the epoxy cure completely first.

Hate to glass over them, as Nick suggests, since it would be nice to be able to remove them later if they faded excessively, or if my wife just got sick of them; suppose I'm leaning toward a topcoat or varnish approach.

Certainly, making decals could be an option, but as I'm greatly appreciative of the beauty of natural wood in my kayaks, having real leaves seems a better compliment to the wood...will save the scanner idea for later.

Thanks again for the terrific feedback, and to Guillemot for hosting this forum!