Both Poaceae

Elymus virginicus vs Sorghastrum nutans

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 Method published

Side by sidefigs. a and b

Elymus virginicus, photographed by Morgan Hay
fig. a Morgan Hay, CC BY 4.0

Elymus virginicus

Virginia wildrye
Sorghastrum nutans, photographed by John Kees
fig. b John Kees, CC0 1.0

Sorghastrum nutans

Indiangrass

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Elymus virginicus Sorghastrum nutans 3 of 19 (16%)

The confusion runs one way only. The model mistakes Elymus virginicus for Sorghastrum nutans, 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 Poaceae. The family does not separate them.
Genus Elymus versus Sorghastrum.

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