Betulaceae and Fagaceae

Betula lenta vs Fagus grandifolia

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

Betula lenta, photographed by Mark Apgar
fig. a Mark Apgar, CC BY 4.0

Betula lenta

sweet birch
Fagus grandifolia, photographed by Jack Forrester
fig. b Jack Forrester, CC BY 4.0

Fagus grandifolia

American beech

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Betula lenta Fagus grandifolia 3 of 20 (15%)

The confusion runs one way only. The model mistakes Betula lenta for Fagus grandifolia, but not the reverse.

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

What actually separates themon the record

Family Betulaceae versus Fagaceae. Different families, which is a real separation.
Genus Betula versus Fagus.
Flowering Peaks in April versus April. Timing does not separate them. (n = 49 and 156.)

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