Both Rubus

Rubus allegheniensis vs Rubus armeniacus

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 Rubus Method published

Side by sidefigs. a and b

Rubus allegheniensis, photographed by rboles
fig. a rboles, CC BY 4.0

Rubus allegheniensis

Allegheny blackberry
Rubus armeniacus, photographed by Loopy30
fig. b Loopy30, CC BY-SA 4.0

Rubus armeniacus

Armenian Blackberry

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Rubus allegheniensis Rubus armeniacus 4 of 19 (21%)

The confusion runs one way only. The model mistakes Rubus allegheniensis for Rubus armeniacus, but not the reverse.

Measured on 38,299 openly licensed, research-grade photographs. Full method and dataset.

What actually separates themon the record

Family Both Rosaceae. The family does not separate them.
Genus Both Rubus. Congeners, which is why this is hard.
Flowering Peaks in June versus June. Timing does not separate them. (n = 1,841 and 2,017.)

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