The only documentation for this plant is the specimen itself and the label in Pursh's handwriting, noted as a copy of Lewis' label:
"Prunus A smaller shrub than the Choak cherry, the natives count it a good fruit. On the Kooskooskae May 29th, 1806"
An image of the specimen in the Lewis and Clark herbarium. . . .
Prunus emarginata (PH-LC 178).
The copyright for this image is retained by the Academy of Natural Sciences of Philadelphia; this image is used with their permission.