Both Urtica

Urtica dioica vs Urtica urens

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 Same genus Urtica Method published

Side by sidefigs. a and b

Urtica dioica, photographed by Paul Cook
fig. a Paul Cook, CC BY 4.0

Urtica dioica

great stinging nettle
Urtica urens, photographed by Daniel Cahen
fig. b Daniel Cahen, CC BY 4.0

Urtica urens

Dwarf Nettle

How often our model gets it wrong measured, not estimated

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

The confusion runs one way only. The model mistakes Urtica dioica for Urtica urens, 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 Urticaceae. The family does not separate them.
Genus Both Urtica. Congeners, which is why this is hard.
Flowering Peaks in July versus February. If the plant is in flower, timing helps. (n = 1,385 and 253.)

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