Asteraceae and Rhamnaceae

Baccharis pilularis vs Ceanothus velutinus

These two are not on this page because a keyword tool suggested them. They are here because our own identification model genuinely mistook one for the other, on real photographs, 4 times. We publish the rate, and then we tell you what actually separates them.

Confused 4x by our model Method published

Side by sidefigs. a and b

Baccharis pilularis, photographed by Amthinkia
fig. a Amthinkia, CC0 1.0

Baccharis pilularis

coyote brush
Ceanothus velutinus, photographed by Josiah Londerée
fig. b Josiah Londerée, CC BY 4.0

Ceanothus velutinus

Snowbrush Ceanothus

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Ceanothus velutinus Baccharis pilularis 4 of 20 (20%)

Measured on 38,949 openly licensed, research-grade photographs. Full method and dataset.

What actually separates themon the record

Family Asteraceae versus Rhamnaceae. Different families, which is a real separation.
Genus Baccharis versus Ceanothus.
Flowering Peaks in October versus June. If the plant is in flower, timing helps. (n = 3,230 and 600.)

What we do not have yet: the diagnostic morphological character that a botanist would key on, from a source we can cite. We are not going to invent one. Until we have it, this page tells you the two are genuinely confusable, how often, and what the taxonomy and the flowering data do and do not settle.

Both recordsfull pages