Vaccinium oxycoccus
 
Swamp Cranberry

Leaf Bottom

Duck Mountain Provincial Park
29-June-2007

I am following Checklist of the Vascular Plants of Saskatchewan in calling this species Vaccinium oxycoccus.  That publication recognizes the varieties intermedium and oxycoccus.

Budd?s Flora (BF) refers to this species as Oxycoccus palustris, and places genus Oxycoccus in family Vacciniaceae.  It calls the varieties quadripetalus and microcarpus.

Flora of Alberta (FOA) refers to the varieties as separate species, Oxycoccus quadripetalus and Oxycoccus microcarpus, and places genus Oxycoccus in family Ericaceae.

According to Budd?s Flora, the two varieties are not cleanly separated and specimens can be found possessing characteristics of both varieties.  Therefore, I am not assigning a variety name to the specimen illustrated on this web site.

Because of the variety of treatments, the notes below do not exactly match the keys in Budd?s Flora and Flora of Alberta.  

 

Characteristics of Vaccinium oxycoccus var. intermedium (= var. quadripetalus) 

leaves mostly elliptical (BF)

leaves narrowly ovate to lanceolate (FOA)

leaves acute to obtuse at apex (FOA)

leaves slightly revolute (FOA)

leaves 5-8 mm long (BF)

leaves 6-11 mm long (FOA)

leaves 2-4 mm wide (FOA)

pedicels puberulent (FOA)

berry 8-10 mm long (BF)

fruit 8-14 mm thick (FOA)

 

Characteristics of Vaccinium oxycoccus var. oxycoccus (= var. microcarpus) 

leaves mostly ovate (BF)

leaves elliptic-ovate (FOA)

leaves pointed at apex (FOA)

leaves strongly revolute (FOA)

leaves 3-5 mm long (BF)

leaves 2-6 mm long (FOA)

leaves 1.5-2 mm wide (FOA)

pedicels usually glabrous (FOA)

berry 6-8 mm long (BF)

fruit 5-10 mm thick (FOA)

 

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

stems filiform and creeping; NOT [stems erect, or if creeping not filiform]

corolla divided nearly to the base, appearing separate; NOT [corolla cup-shaped or urn-shaped or campanulate]

corolla lobes reflexed

ovary inferior; NOT [ovary superior]

fruit fleshy

 

Vacciniaceae: Answers to key questions in Budd's Flora  leading to this family. 

leaves alternate; NOT [leaves opposite or whorled]

flowers NOT in heads

flowers with two floral rings, but with the petals wholly or partly united forming a tube or bell (note petals are united only at the very base and appear separate in this species)

ovary inferior; NOT [ovary superior]

fruit fleshy; NOT [fruit usually a capsule, sometimes a mealy-fleshy drupe]

fruit many-seeded; NOT [fruit 1-seeded]