Dave,
I once tried setting an old round bale at waters edge(some of it in the water, some of it out)...the only thing it did, as far as I could tell, was provide an environment for cat tails to flourish...the only cat tails I have ever had in my ponds came from that one instance of setting that round bale in the water's edge, They thrived in that one spot until I used a back-hoe and removed the remanents of the hay. No cat tails since.
