Why did they name the plant cattails?

Answer 1

The following ideas are educated guesses only.

Probably because it looks like a cat tail, thick and bushy, just before going to seed. The fiber appears like fur in the winter just before sowing the seeds to the wind, although a pretty straight tail. Catch a glimpse of one just before and they do look very fluffy, very unlike the sausage link on a pole as in most times of the year.

I would be surprised if the material was not used for down in the past as it is very light and springy, with most excellent insulating properties. Properly encased in reed or flax, it could make a coat. For 20 minutes work one can gather a pillow's worth in a marsh if the area is hard frozen, therefore much easier to move around. And one could have had children do it, simply bend the stalk down. What else is there to do on windless warmer 30 degree F days in areas with long winters? If so, this would be the most important time for observing the plant at close quarters in earlier agrarian societies.

Pripet/Pinsk Marshes in Poland/Ukraine/Belarus for example is 120 miles by 300 miles, or about 40,000 square miles, and famous stubborn self reliance of the independent minded locals. There is no chance a luxury of cat tail silk stuffing for the plucking would be overlooked, and the area was a refuge for the wars waged in the area (horses could not stand on the marshy, quaking grounds, equalizing the odds for common folk, and lots of bushy cover. In the winter, there was little or no fodder and still the potential for getting stuck).