photos:

If additional photos will help, let me know. Long skinny plants are challenging! Thanks.

Thanks GG. It does look irisey, but this might be too deep (based on what I've read). Cattail would be awfully fun though. I guess I will just have to be patient and see what it does next, huh?

Definitely not Iris. It is a Typha. Most likely Typha Angustipholia or something closely related. Does your bucket have fish? The water Lily looks good. The Cattail will quickly take over the container. You may want to remove one of them to slow down the invasion.

Why is it "definitely not iris"? When not in flower, Iris pseudacorus and typha are virtually indistinguishable, unless you examine how the leaves emerge from the root crown. And the pseudacorus is well able to grow in several inches of standing water. There are vast swathes of it growing in wetlands adjacent to Lake Washington that are always under 6-12" of water.

Respectfully agree it may be difficult to distinguish on newly emergent leaves without seeing the root base. However the original post states the plant is 5 feet above the water, at that stage there are NO similarities between the water Iris and a Cattail. The iris leaves would be three times as wide and would have bloomed long ago.

Do a little more research. Iris pseudacorus can easily achieve 6' in height. And the leaves of this species are quite narrow - no more than 1 1/4 to 1 1/2 inches. Young plants do not always flower either.

I am not saying it isn't typha.....only that it is not reasonable to dismiss iris just based on visuals provided by a photo. There is just not enough data to be certain in either case.

I also think it's a Typha.

...and I thought it was just grass until it kept growing up...

I hope it makes it long enough to bloom! I didn't include a good size reference I realize. If it helps, the tank is about 41" x 25" across the top and 32" tall. 70 gallons capacity.

In the meantime, short of pulling it up, is there anything I could take a picture of that would help narrow it? I don't suppose either of these candidates have remarkable scents or anything easy.

Is it possible that seeds were stuck to the water hyacinth I bought at the hardware store from a tub of plants? I intentionally didn't clean it because I wanted to grow duckweed for my goldfish. (That isn't going well but I'm not really trying.)

(I think there are fish in there--white cloud minnows. I haven't seen them since it went all green, and they were pretty elusive anyway. The mosquitoes aren't back so I think the fish are still alive.)

Texture of the two is different. The leaves of Typha would be sharper edged and stiffer in texture. Iris is more juicy, more like bulb foliage. Iris has roots which are like knobbly tubers. Red in cross section. Iris leaves are in flat, fan like sheaves. Typha sheaves are not flat. I'm pretty firmly in the Typha camp.

Agreed. Also the description of the triangular leaf base lends itself to Typha not Iris.

Newbie question here, but do aquatic iris leaves resemble bearded iris in how they are arranged in flat bundles? (My plant vocabulary is a little bit weak, apparently.)

These are definitely not oriented that way.

No. Seedlings - and new grow rising from existing rhizomes - produce foliage appearing in clusters. One website even refers to them as "rosettes". So no flat fans or 'bundles' like a bearded iris but a cluster of tightly overlapping leaves at the base, which often DO appear triangular in shape due to the defined midrib and overlapping.

Where the iris has naturalized is very often in the same area - often intermixed - with the cattails. If neither plant is showing any signs of flowers or seeds, they are very difficult to tell apart (unless dug up and examined closely), which is also something acknowledged by many websites.

That it sprung up spontaneously in that depth of water would lead more to typha than iris simply because the iris germinates best in moist shoreline areas rather than under complete inundation, which the typha will tolerate.

If a cattail, it should produce flowers next season. The iris will not flower until it is 3 years old.

The Iris pseudacorus in my pond always produce flat fans. Just like a bearded Iris. Never bundles or rosettes.

I pulled one up. In the original post's top photo, you can see what looks like 2 plants, but the one in the foreground actually has a smaller one coming up right next to it. Now, if you jiggle one of the big ones, the other jiggles as well; they are definitely attached. The little one seemed free so I yanked it, in the interest of science and whatnot.

Does that help? :)

Thanks again!

Enjoy your Typha