Both Asteraceae

Grindelia hirsutula vs Sonchus oleraceus

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

Grindelia hirsutula, photographed by joergmlpts
fig. a joergmlpts, CC BY 4.0

Grindelia hirsutula

Hairy Gumweed
Sonchus oleraceus, photographed by Andrew Tree
fig. b Andrew Tree, CC BY 4.0

Sonchus oleraceus

Common Sow-thistle

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Grindelia hirsutula Sonchus oleraceus 3 of 20 (15%)

The confusion runs one way only. The model mistakes Grindelia hirsutula for Sonchus oleraceus, 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 Asteraceae. The family does not separate them.
Genus Grindelia versus Sonchus.
Flowering Peaks in February versus November. If the plant is in flower, timing helps. (n = 1,317 and 3,863.)

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