I've had the following request out on the SRGC forum for some time without much luck. I'll try again here - these are seldom or never offered in the seedexes. I understand that seed is ripe quite early in the year:
"I am looking for various North American Toothworts (Dentaria spp) such as Dentaria laciniata, multifida, heterophylla, diphylla, californica, tenella, pucherrima, gemmata, nuttallii etc. Can anyone help?
Pay or trade."