A Rudbeckia Thief?

[TygrBright]

2. Correct, no root material remaining.

But also almost no disturbance of the soil...

Flower-carrying stems I call scapes. The two plants that are gone had many of them. The remaining four are in a slightly less well-irrigated area and haven't thrown out so many, yet.

The only thing I know of that reliably eats them is rabbits, but rabbits usually nibble some on all the plants, not systematically devour only two in their entirety.

I just dunno.... I can't really see anyone sneaking into our yard to carefully uproot and steal a coupla plants, either, but what do I know?

baffledly,
Bright