Both Asteraceae

Coreopsis tripteris vs Rudbeckia hirta

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

Coreopsis tripteris, photographed by Yann Kemper
fig. a Yann Kemper, CC0 1.0

Coreopsis tripteris

tall coreopsis
Rudbeckia hirta, photographed by Ryan Sorrells
fig. b Ryan Sorrells, CC BY 4.0

Rudbeckia hirta

black-eyed Susan

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Coreopsis tripteris Rudbeckia hirta 4 of 20 (20%)

The confusion runs one way only. The model mistakes Coreopsis tripteris for Rudbeckia hirta, but not the reverse.

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

What actually separates themon the record

Family Both Asteraceae. The family does not separate them.
Genus Coreopsis versus Rudbeckia.
Flowering Peaks in August versus July. If the plant is in flower, timing helps. (n = 414 and 11,782.)

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