Centaurea
nigrescens
PNW
BC
ID
OR
WA
44 specimens from 10 herbaria:
British Columbia (2)
Idaho (11)
Oregon (15)
Washington (16)
30 images from 6 herbaria:
IDE (19)
NOCA (4)
OSC (1)
PSM (1)
SRP (1)
WTU (4)
