Sorbus scopulina

Western Mountain Ash

Flower Side

Centre Block, Cypress Hills Interprovincial Park
26-June-2008

The bases of the sepals, petals, and stamens have fused to form a hypanthium.

Scopulina: Answers to key questions in Budd's Flora (BF)  and Flora of Alberta (FOA) leading to this genus. 
shrubs or small trees less than 5 m high; NOT [trees 6-10 m high]
winter-buds glabrous, glutinous or rufous-pilose; NOT [winter-buds densely white-villose]
leaflets usually 11-13; NOT [leaflets usually 7-11] 
leaflets generally less than 13; NOT [leaflets 13 or more]
leaflets acute or acuminate at apex; NOT [leaflets rounded at the apex] (FOA)
leaflets serrate to near the base; NOT [leaflets entire toward the base]
young twigs and inflorescence white-pubescent; NOT [young twigs and inflorescence with rust-coloured hairs]
inflorescence broad, flat-topped; NOT [inflorescence small, rounded]
styles 3-5; NOT [styles 2-3]

 

Sorbus: Answers to key questions in Budd's Flora (BF)  and Flora of Alberta (FOA) leading to this genus. 
small trees; NOT [shrubs], NOT [herbs, or with a woody base and otherwise herbaceous]
leaves pinnately compound; NOT [leaves simple], NOT [leaves lobed]
leaflets 11-17; NOT [leaflets 3-11]
flowers in broad compound corymbs
flowers white; NOT [flowers yellow or pink]
ovary inferior, enclosed in and adnate to the hypanthium; NOT [ovary or ovaries superior, hypanthium shaped like a saucer, cup or urn and free from the ovary]
fruit a pome but often berry-like, more or less fleshy; NOT [fruit dry]

 

Rosaceae: Answers to key questions in Budd's Flora leading to this family.  These answers do not apply to all members of the Rosaceae family, but they all do apply to this species.
shrubs or trees; NOT [herbs]
plants NOT climbing
plants with normal leaves
leaves alternate; NOT [leaves opposite]
leaves compound; NOT [leaves simple]
leaflets NOT leathery
leaflets NOT spinose-tipped
flowers with two floral rings, and with each petal distinct from the others]
flowers perfect; NOT [flowers dioecious or perfect]
flowers NOT legume-like
petals 5
stamens numerous; NOT [stamens 5]
fruit not a legume