[url=https://www.ecy.wa.gov/Programs/wq/plants/native/cattail.html]Cattail is a native food source[/url]par excellence in many different stages of growth, and a native habitat plant of note. I never see redwing blackbirds without them nearby somewhere when I kayak.
And they would guild nicely with [url=https://plants.usda.gov/factsheet/pdf/fs_sala2.pdf]duck potato[/url], a survival food that was cropped by indigenous tribes. Our [url=https://en.wikipedia.org/wiki/Nelumbo_lutea]native lotus[/url]would fit into this crew too, although it can be a bit rambunctious... but just as edible as it's Asian cousin and just a bit deeper than the duck potato.
Cattail at the margin, duck potato at 6-12" and the
Nelumbo lutea at 12-18" Kayaking will be difficult, but there is a lot of food there...
HG