There definitely used to be a Bee Flower of "None" but I haven't seen it in a long time (and I've always been searching for it). I believe I recall a previous discussion explaining that it had been removed and all bees have a specific flower type (which is why you see "Wheat" instead of "None" now). My base is overgrown with flowers but I long ago stopped caring about it. It's ugly and a total mess but whatever. I've done genetics on all my bees of course but I just left "Flowers" alone. But yeah, "Stone" makes the most sense I think, if there's no "Flowers: None" in your modpack's bees.
Most Bee wikis are out-of-date (I'm doing bees in Infinity right now myself), it's impossible to keep up with every mod/modpack/update. Some wikis do it better than others, for instance here is a link to the Bee Species as of FTB Ultimate modpack days (circa 2013), it's still there and research-able:
http://ftbwiki.org/index.php?title=Bee_Species&direction=prev&oldid=78685
On a sad but unfortunately related note... this awesome link has now died, seemingly for good:
http://mc.nessirojgaming.eu/bees/index.php?title=Category:Attributes
Some kind soul had put up a series of oh-so-valuable pages on Bees which had information that just isn't found in any wiki, anywhere... it listed every Bee Attribute, and then sub-listed every bee that had that Attribute... and all that data is gone now, like dust in the wind. Sad, but its also my fault for never copying the webpages somehow. You want to know which Bee had a Temperature Tolerance of "Both 3"? That page could tell ya in a few clicks (Answer: Doctoral Bee).
There's a spoiler on page 2 of this 2013 thread where it says "An overview of the best bee traits:", it might be the best replacement available now for those pages that are gone:
http://forum.feed-the-beast.com/threads/bee-traits.9932/page-2
But look what it says in there (proof that it used to be in the game):
"Flowers:
- None (e.g. Arid Bee from Extra Bees)"
Maybe you should check Arid Bee just to be sure. I turned all mine into DNA and too lazy to go make another one to see. Let us know if you check.
My own question (haven't taken the time to check): Does Marble count as "Stone" in terms of the Flower trait? My base is made from Marble blocks (Chisel's, not ProjectRed's).