I looked at Amas, Crimson King, William A Setchell.
Amas and William are yellow beard. Crimson King is white.
However, it seems to be a matter of how far down the fall the color of the beard extends. I looked at photos from the Historic Society and Garden Org. For example Crimson King, the color is yellow in the throat and the beard is white further out. I am not certain but that "throat" may be correctly called "claw."
Some Iris, the color is definite all the way yellow but with the Historics, it seems as if they are all yellow at the beginning and then are differentiated by when or if the beard becomes white.
Maybe someone who has more knowledge will post about beards because it is the single distinguishing feature among some of the oldies.
