Vaccinium oxycoccus

Small Cranberry

Small Cranberry, photo courtesy of David H. Firmage

Flora, fauna, earth, and sky...
The natural history of the northwoods



  • Vaccinium, from the Latin
  • oxycoccus, from the Greek oxus (oxys) "sharp, pointed; dazzling; shrill; pungent" and kokkos (coccos) "berry of the scarlet oak, used as a red dye"
  • Small Cranberry, from
  • Other common names include: Bog Cranberry, Wild Cranberry, Swamp Cranberry, Muileag (Gaelic)


  • Kingdom Plantae, the Plants
    • Division Magnoliophyta, the Angiosperms (flowering plants)
      • Class Magnoliopsida, the Dicotyledons
      • Subclass Dilleniidae
  • Taxonomic Serial Number: 23609
  • Also known as Oxycoccos microcarpus, Oxycoccos palustris, Oxycoccos oxycoccos, Oxycoccos quadripetalus, Oxycoccos intermedius
  • The taxonomically complex genus Vaccinium has been divided into a number of subgenera or sections. The cranberry genera are often segregated as the subgenus or genus Oxycoccos.


  • In the BWCA, generally only found on sphagnum mats. Its delicate scale and woody, thread sized stems are unlike anything else.


  • A very small, prostrate, evergreen subshrub.
  • Stems very slender, vinelike, rooting at the nodes.
  • Leaves lance-shaped, leathery.
  • Flowers pink to red, borne singly or in clusters at ends of stems.
  • Fruit a red, juicy berry; often persisting through the winter.
  • Underground perennating structures are generally well below the soil surface.
  • Mycorrhizal associations on portions of roots allow for improved plant nutrient levels and growth rates in acid or peat soils.


  • Alaska to Labrador, Greenland, and Newfoundland; south through New England, the northern portions of the Great Lakes States, and western Washington and Oregon. Also Europe and Asia.


  • Ombrotrophic sphagnum bogs and minerotrophic fens in moist coastal and boreal forests. Grows on peat in poorly drained sites with a very high water table. The ground may be saturated for most or part of the year. The bog sites derive water from precipitation only and are generally nutrient-poor and low in productivity.
  • Soil highly acidic; pH from about 2.9 to 4.7.
  • Bogs are generally level but are often patterned by scattered mounds of sphagnum moss. Small Cranberry often grows on these hummocks.
  • One of the first colonizers of burned bogs, increasing in abundance with repeated fires.
  • Shade intolerant, generally only present as a relic in climax bogs that have developed a conifer overstory.
  • An indicator of moist to very wet, nitrogen-poor soils and high surface groundwater. Also an indicator of coniferous swamps.


  • Members of the family Ericaceae easily regenerate from rhizomes following fire using ash nutrients for rapid growth. Able to survive low to moderate severity fires because rhizomes are found well below the surface of the bog.
  • Wildfires are infrequent in the wet or saturated habitats that bog cranberry generally occupies. Fire usually top-kills Small Cranberry. Severe fires that remove the underlying sphagnum layer generally kill underground reproductive organs.
  • Without fire, eventually shaded out by taller shrub and tree species. Commercial cranberry growers often use fire to maintain bogs and increase fruiting.



  • Native Americans used the berries, twigs, and bark for medicinal purposes.


  • Fruits have good flavor and often used to make jams and jellies. However, they are seldom abundant enough to be gathered in large quantities. Commercial cultivation of Small Cranberry is not widespread in the US (unlike Vaccinium macrocarpon, Large Cranberry) but is important in Russia.


  • Reproduces by seed and vegetatively by rhizomes
  • Vegetative regeneration is the most important mode of reproduction. It can also establish by seed; seedlings, however, are rare.
  • Self-pollinating, but pollination by insects (especially bees) increases seed production. Seeds do not germinate immediately after berries become ripe, but dormancy can be overcome by after ripening.
  • Seed dispersal by birds and animals that eat the fruits.
  • Regenerates vegetatively by sprouting from rhizomes and by layering.


  • By seed, following cold stratification. Storage of seeds at 32º F for 6-7 months allows for germination of seeds at 77º F.
  • Does not respond well to transplanting.


  • A very difficult plant to cultivate.
  • Susceptible to many different fungal diseases.


Boreal border
Last updated on 2 August 1999