Hi Bill,
Apologies for dawdling, some rather demanding projects to surmount etc...
Odd you should mention floating islands, I'm tinkering with a little sedge little more than 4" tall which self seeds and makes a floating island all on it's own. Currently it is an island a couple of feet wide and new islands are springing up all over a 40' pond (eek)
Aquatic iris have buoyant rhisomes and roots, if they were to be jammed into position over time they would form an extensive buoyant knot of plants on any kind of structure. A string of those durable bread trays lashed together would suffice...
The neat thing about aquatic iris, they make real tough fibrous masses which will cope with fish grazing at their roots
One downside, having foliage like sails, they would catch the breeze and tug hard in a storm on any anchor
How buoyant are they? hmmm, I planted a few chunks of Laevigata snowdrift on a 3 gallon bucket of heavy soil in 30" of water. In about two years the plant mass was a gently drifting floating island...
A very popular spot for tiddlers fish fry among those roots and shoots... The big fellas liked loafing in the shade beneath the islands...
Regards, andy
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