If you linked together durable plastic crates, as used for carrying bread ot bottled merchandise, with nylon rope, you could make a stable buoyant 'raft' that could be tethered to rise and fall with lake levels...
Aquatic iris are buoyant and mat forming when their numbers merge, rather suitable for the task of a floating island...
You may have to start them in a side pond until the plants 'knots' well together, then drain them off so they are easy to move to add to the deep water pond
Regards, andy
http://community.webshots.com/user/adavisus
