Both Poaceae
Dactylis glomerata vs Holcus lanatus
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 Method published
Side by sidefigs. a and b
Dactylis glomerata
orchard grass
Holcus lanatus
Yorkshire fog
How often our model gets it wrong measured, not estimated
| When the plant was | The model said | How often |
|---|---|---|
| Holcus lanatus | Dactylis glomerata | 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 Poaceae. The family does not separate them. |
|---|---|
| Genus | Dactylis versus Holcus. |
| Flowering | Peaks in June versus June. Timing does not separate them. (n = 7,174 and 792.) |
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.