I think they will spawn on anything that has an underside. I can't say if they have preferred materials of not, but if there is competition for spawning space I would say they would use anything.

I've heard here on PBF that they prefer things that stay put over things that float around the pond. I have always staked my pallets in place. They can move a little with water level changes, but don't float all over the pond. But that is something I just heard someone else here on PBF say. Can't say for sure.

I would not think the treated wood would be good, but in not too long algae will be growing on it and by then I would guess the FHM would use it. They might not take to it right away.

They will use the underside of a dock or whatever they can find. But once you get predators big enough to eat them, they will try and seek something with some protection if available.

John

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