Clematis occidentalis
 
Purple Virgin's-Bower

Flower Top

Centre Block, Cypress Hills Interprovincial Park
12-June-2013

Note there are four coloured sepals and no petals.

Occidentalis: Answers to key questions in Budd's Flora and Flora of Alberta leading to this species. 

leaves with 3 leaflets; NOT [leaves with 5 leaflets]

flowers solitary; NOT [flowers in panicles or corymbs]

flowers blue or purple; NOT [flowers yellow or white]

 

Clematis: Answers to key questions in Budd's Flora and Flora of Alberta leading to this genus. 

woody climbing plants

plants with opposite leaves; NOT [leaves either basal or alternate]

plants without petals but with colored sepals

fruit with persistent feathery style

 

Ranunculaceae: Answers to key questions in Budd's Flora  leading to this family.  Not all the answers apply to all genera in Ranunculaceae found in the Canadian prairies, but they all apply to Clematis. 

herbs; NOT [shrubs or trees]

plants not parasitic on branches of trees

plants rooted in soil or water

land plants; NOT [water plants]

plants with stem or stemless, but with more than one pair of leaves; NOT [plants stemless with a single pair of large reniform leaves]

plants climbing

leaves not scale-like

leaves opposite; NOT [leaves alternate, lower ones sometimes opposite]

leaves without stipules; NOT [leaves with stipules free or sheathing the stem]

flowers not imbedded in stem

flowers with only one floral ring, with sepals but not petals

stamens and pistils in each flower; NOT [stamens or pistils in separate flowers on the same plant]

calyx colored