Yet another project in the "pond" collection (sounds more appetizing than "swamp", right?), to be company for the frog, lily pads, and water lily. All you need to make cattails are Nilla Wafers, a Styrofoam block, a dusting pouch filled with a 50/50 mix of cornstarch and powdered sugar, stiff consistency brown and green royal icing, round tip #8, leaf tip #352, and dry linguine (spaghetti would probably look more realistic, but I didn't have any on hand).
Pipe another line on the other side of the linguine directly opposite it.
Dust your fingertips especially thoroughly against the dusting pouch and pinch the icing together around the linguine.
Re-dust your fingertips and tap along the seam until it disappears. Don't worry about making the cattails look perfect; last I checked, they aren't perfectly cylindrical in nature, either.