Both Trillium

Trillium grandiflorum vs Trillium ovatum

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

Confused 4x by our model Same genus Trillium Method published

Side by sidefigs. a and b

Trillium grandiflorum, photographed by Lorie Shaull
fig. a Lorie Shaull, CC BY-SA 4.0

Trillium grandiflorum

large white trillium
Trillium ovatum, photographed by Timothy McNitt
fig. b Timothy McNitt, CC BY 4.0

Trillium ovatum

Pacific trillium

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Trillium ovatum Trillium grandiflorum 4 of 20 (20%)

Measured on 38,949 openly licensed, research-grade photographs. Full method and dataset.

What actually separates themon the record

Family Both Melanthiaceae. The family does not separate them.
Genus Both Trillium. Congeners, which is why this is hard.
Flowering Peaks in May versus February. If the plant is in flower, timing helps. (n = 19,097 and 10,470.)

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