Both Arbutus

Arbutus menziesii vs Arbutus xalapensis

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

Confused 8x by our model Same genus Arbutus Method published

Side by sidefigs. a and b

Arbutus menziesii, photographed by Erin Springinotic
fig. a Erin Springinotic, CC0 1.0

Arbutus menziesii

Pacific madrone
Arbutus xalapensis, photographed by Reid Hardin
fig. b Reid Hardin, CC BY 4.0

Arbutus xalapensis

Texas madrone

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Arbutus xalapensis Arbutus menziesii 8 of 17 (47%)

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

What actually separates themon the record

Family Both Ericaceae. The family does not separate them.
Genus Both Arbutus. Congeners, which is why this is hard.
Flowering Peaks in April versus March. If the plant is in flower, timing helps. (n = 1,037 and 262.)

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