Polygonaceae and Portulacaceae

Polygonum aviculare vs Portulaca oleracea

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

Polygonum aviculare, photographed by Charla
fig. a Charla, CC BY 4.0

Polygonum aviculare

Prostrate Knotweed
Portulaca oleracea, photographed by Alexis Tinker-Tsavalas
fig. b Alexis Tinker-Tsavalas, CC BY 4.0

Portulaca oleracea

Common Purslane

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Polygonum aviculare Portulaca oleracea 3 of 20 (15%)

The confusion runs one way only. The model mistakes Polygonum aviculare for Portulaca oleracea, but not the reverse.

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

What actually separates themon the record

Family Polygonaceae versus Portulacaceae. Different families, which is a real separation.
Genus Polygonum versus Portulaca.
Flowering Peaks in October versus March. If the plant is in flower, timing helps. (n = 607 and 1,610.)

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