Both Fagus

Fagus grandifolia vs Fagus sylvatica

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

Confused 6x by our model Same genus Fagus Method published

Side by sidefigs. a and b

Fagus grandifolia, photographed by Jack Forrester
fig. a Jack Forrester, CC BY 4.0

Fagus grandifolia

American beech
Fagus sylvatica, photographed by Jason Grant
fig. b Jason Grant, CC BY 4.0

Fagus sylvatica

European beech

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Fagus sylvatica Fagus grandifolia 6 of 20 (30%)

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

What actually separates themon the record

Family Both Fagaceae. The family does not separate them.
Genus Both Fagus. Congeners, which is why this is hard.
Flowering Peaks in April versus April. Timing does not separate them. (n = 156 and 155.)

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