Cannabaceae and Urticaceae

Humulus lupulus vs Urtica dioica

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

Humulus lupulus, photographed by Alexis Tinker-Tsavalas
fig. a Alexis Tinker-Tsavalas, CC BY 4.0

Humulus lupulus

common hops
Urtica dioica, photographed by Paul Cook
fig. b Paul Cook, CC BY 4.0

Urtica dioica

great stinging nettle

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Humulus lupulus Urtica dioica 3 of 20 (15%)

The confusion runs one way only. The model mistakes Humulus lupulus for Urtica dioica, but not the reverse.

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

What actually separates themon the record

Family Cannabaceae versus Urticaceae. Different families, which is a real separation.
Genus Humulus versus Urtica.
Flowering Peaks in August versus June. If the plant is in flower, timing helps. (n = 365 and 1,723.)

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