Jake,
Decoys that are hand carved are usually wood ( lots of softwood choices there : linden, cedar, tupelo, balsa, and on...), or cork. I usually do my birds in high density cork with wooden heads and tail inserts. The frond-rig I'm referring to in my post is something that I started when someone sent me a box of large palm fronds from So. California to see what I might come up with.
Apparently palm fronds were a cheap and quick alternative for many makers in CA back in the day. They have largely fallen out of use, but one of the big carving shows began to include a frond category for the fun of it. Idea is to try and capture the essence of a bird using a frond, while retaining as much of the natural shape of the frond while doing so. I have enjoyed working with them, and think they project a very "ducky" look. Implementing some updated techniques for sealing and painting them, and using a keel has produced some birds that I think will be unique as well as fun to hunt over.
Here are pictures of the first two birds I have completed. They'll be part of a seven-bird rig (5 blacks / pair of mallards) that I hope to have completed by fall. The third picture shows cork blacks at use in my rig so you can see the contrast in style.