I thought the same thing, Sheryl. I think of taproot as a carrot, parsnip, or beet. Butterfly weed hass a taproot. Poppies have taproots. Dandelions have taproots. My coneflowers don't have anything that I think resembles a tap root.
Kind of an accusatory tone in the article, too. If a plant doesn't survive in my yard, I see it as not hardy. Whether it meets it's demise as a result of cold temps or winter wet doesn't matter to me. If it doesn't survive my 73" of rain, it's not hardy to me. I can't make the rain stop. Speaking of which, we're having another monsoon.
Karen