Mystery plant

[PBSJones]

Last year I put together two small ponds made from 50 gallon tubs. I had irises in one, which had gotten too big for their pot. I divided them and put a couple of them into the other pond.

Now, what I was sure were irises are...not. They've grown about 4 1/2 feet tall with thin, concave leaves. The bases look nothing like the other irises I have.  Hopefully, the picture comes along with my text.

Does anyone have an idea what this plant could be? Is it just an iris that went nuts?  Just to the right of the mystery plants is an actual iris (I know for sure, because it bloomed) that I've cut back for the winter. (Ignore the cherry tomatoes that have decided to use the plant as a scaffold.)

[dperry]

Looks like Typha (cattail) to me.  Easy for them to get started "out of nowhere" as their seeds are windblown.

[Bob_A]

Agree with Don, looks like cattail.

[PBSJones]

 Thanks, guys! Last night I was looking at some of Mr. Perry's photos of his amazing pond, and had started reaching the same conclusion. Those sneaky little buggers! We live within a half mile of a large creek, so it's quite possible.

[matherfish]

I had cat tails show up in one of my lotus tubs last year. We are a good distance from other ponds but not all that far. Seeds came in from birds or wind but they sprouted and grew. I got rid of them last fall.