PS.
I did not even consider the maintenance! I certainly don't want to ferry my mower/weed eater every week so I'll have to look at other ground cover choices if I do end up with an island.
Regarding the islands eroding and silting in the pond though... does it matter (from an erosion standpoint) if the island has steep (near vertical banks) or gently sloping (say 4:1) sides?
