I have both Hemerocallis flava (or lilioasphadelus?) and Hemerocallis minor. Both lose all leaves in the winter-you can't even find them. Flava has fleshy enlarged roots while minor has fibrous roots. For years I thought a low early yellow daylily was minor, but now after rereading Stout I think the one I bought as minor is really H. nana. It seems to have fibrous roots- or at least mine does. Nana seems to cross with every thing all by itself and is shedding seeds all around itself now. I think it has teamed up with Stella, Happy Returns, middendorfs, dumortierii and Heaven knows what, as they are all different shapes and height. Some other early Spring seedlings disappear as well and if I dig around the clump I find that the growing point of the fan looks almost like the tip of a bulb just a rounded point with the leaves inside. Minor has been called a variety of flava, by the way, but Stout thought they were quite different and they are from narrow leaves to thick scapes on flava and thin wiry scapes on minor to different roots to huge seed pods on flava with big black seeds to small narrow pods on minor with the smallest seeds of any daylily-------------------------------------------------------------Weedy
leaves of this seedling completely disappear in winter it's miserably infertile too!