Both Juglans

Juglans cinerea vs Juglans nigra

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, 3 times. We publish the rate, and then we tell you what actually separates them.

Confused 3x by our model Same genus Juglans Method published

Side by sidefigs. a and b

Juglans cinerea, photographed by Michael J. Papay
fig. a Michael J. Papay, CC BY 4.0

Juglans cinerea

Butternut
Juglans nigra, photographed by Violet T.
fig. b Violet T., CC BY 4.0

Juglans nigra

eastern black walnut

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Juglans cinerea Juglans nigra 3 of 20 (15%)

The confusion runs one way only. The model mistakes Juglans cinerea for Juglans nigra, 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 Juglandaceae. The family does not separate them.
Genus Both Juglans. Congeners, which is why this is hard.
Flowering Peaks in May versus May. Timing does not separate them. (n = 30 and 72.)

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