Guys you're not going to believe this but I've had them grow in at least 4 feet of water and still come out of the water another three feet.

CJ the reason you may not have seen them grow in as deep a water in your region vs. ours may be soil type or as alluded to species?

They are easy to control if they show up with a good systemic herbicide designed for Cattails. Be sure to use a a surfactent though as the leaves are quite waxy.

So if one doesn't want them to take over spray them. Just don't wait until they do take over like I did once!

If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.