Pumila: Answers to key questions in Budd's Flora leading to this species. 

	low shrub; NOT [tall shrub or small tree]
	flowers in umbels; NOT [flowers in corymbs], NOT [flowers in long racemes at the ends of the branches]
	flowers 6-12 mm across; NOT [flowers 12-25 mm across]
	stone NOT flattened; NOT [stone more or less flattened]
	stone NOT grooved; NOT [stone with a groove on the end]

Prunus: Answers to key questions in Budd's Flora  and Flora of Alberta leading to this genus.  Not all of these answers apply to all members of Prunus, but they all do apply to this species.

	shrubs or trees; NOT [herbs, or with a woody base and otherwise herbaceous]
	plants taller; NOT [creeping dwarf shrubs]
	shrubs or trees not spiny; NOT [spiny shrubs or small trees]
	leaves simple; NOT [leaves compound or lobed]
	leaves serrate or toothed; NOT [leaves entire]
	flowers usually more numerous; NOT [flowers solitary on a long peduncle]
	hypanthium shaped like a saucer, cup or urn
	carpel 1; NOT [carpels 2 or more]
	ovary or ovaries superior; NOT [ovary inferior]
	hypanthium free from the ovary; NOT [ovary enclosed in and adnate to the hypanthium]
	fruit fleshy; NOT [fruit a leathery follicle]
	fruit a red or black drupe with a single stone; NOT [fruit a berry-like pome with several seeds]

Umbelliferae: Answers to key questions in Budd's Flora  leading to this family. Not all of these answers apply to all members of Rosaceae, but they all do apply to this species.

	shrubs or trees; NOT [herbs]
	plants NOT climbing
	stems not armed with prickles, or if prickled, only one leaf per node; NOT [stems armed with prickles, leaves several at the nodes]
	plants with normal leaves
	leaves alternate; NOT [leaves opposite]
	leaves simple; NOT [leaves compound]
	flowers with two floral rings, and with each petal distinct from the others]
	stamens numerous; NOT [stamens less than 10]
	fruit without a tongue-shaped bract; NOT [fruit with a tongue-shaped bract adhering to the peduncle]