Cattails are one of the most useful plants out there.
Cattail roots are best after the first freeze. You have to pound them and then let the starch settle out in water. The roots are very fibrous. I know some people cook them whole then chew them up and spit out the fibers.
He pulled off way more leaf than I ever do. Lots of that white part of the leaf is soft and easy to eat raw. I usually slice it up for salad.
The very young green cattail heads can be cooked up. The pollen can be shaked into a bag and use as a flour.
Cattail leaves can be used for weaving baskets and mats. The fluff can be harvested from the heads to be used as a batting or fill.
We're in the middle of farm ground, so there's not much foraging around here unless we drive somewhere. Our weeds vary somewhat from year to year, whatever the wind is blowing in.
We just got our first batch of dandelion greens, have dug roots for tea, eat the flowers. I picked a tub of flowers one year then was too tired to make the jelly, so I bagged 'em and put 'em in the frig. The next morning they looked wretched, so I pitched 'em.
Lambsquarter for sure, wild hemp leaves, purslane when I find it, wild violets when I take the time to locate them. Mallow is nice, wood sorrel, Shepherd's Purse (a lot of work for little reward). We have some kind of dock here, but by the time I see it, it's past it's prime.
Of course, wild sunflowers. But the seeds are so tiny, I thought the better use would be for chicken feed. I always left the wild sunflowers in the chicken run. Gave the birds some shade, then seeds dropped later.
Dang, I just did a search for 'edible weeds in Kansas' and found a long list! Try it for your state.
There are more edible things around here than I thought. I won't gather anything that's next to the road because of car exhaust. Unfortunately, some things that I want, I haven't spotted, like elderberry.
my concern with almost any wetland or river foraging around here is the agricultural poisons. cattails are in many ditches, but those ditches are runoff from heavily sprayed fields. the same with all the rivers.
if i can't grow it or know that the area hasn't been used for agriculture i won't harvest from there. too many poisons being used and some persist for a long time.