Both Frangula

Frangula californica vs Frangula purshiana

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 Same genus Frangula Method published

Side by sidefigs. a and b

Frangula californica, photographed by Jeremiah Degenhardt
fig. a Jeremiah Degenhardt, CC BY 4.0

Frangula californica

coffeeberry
Frangula purshiana, photographed by Casey H. Richart
fig. b Casey H. Richart, CC BY 4.0

Frangula purshiana

Cascara

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Frangula purshiana Frangula californica 4 of 20 (20%)

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

What actually separates themon the record

Family Both Rhamnaceae. The family does not separate them.
Genus Both Frangula. Congeners, which is why this is hard.
Flowering Peaks in May versus May. Timing does not separate them. (n = 642 and 91.)

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