Lythraceae and Lamiaceae
Lythrum salicaria vs Physostegia virginiana
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
Lythrum salicaria
purple loosestrife
Physostegia virginiana
obedient plant
How often our model gets it wrong measured, not estimated
| When the plant was | The model said | How often |
|---|---|---|
| Physostegia virginiana | Lythrum salicaria | 3 of 19 (16%) |
Measured on 38,299 openly licensed, research-grade photographs. Full method and dataset.
What actually separates themon the record
| Family | Lythraceae versus Lamiaceae. Different families, which is a real separation. |
|---|---|
| Genus | Lythrum versus Physostegia. |
| Flowering | Peaks in August versus August. Timing does not separate them. (n = 13,173 and 1,823.) |
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.