Arctostaphylos uva-ursi

Bearberry

Arctostaphyllos uva-ursi, Bearberry; Kawishiwi River, BWCA

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

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Name:

  • Arctostaphylos, from the Greek, 'arktos (arktos), "bear" (into Latin as the "bear constellations", hence "north"), stafulh (staphyle), "grapes"
  • uva-ursi, from the Latin uva, "grape, berry of the vine", ursi, bear; "bear's grape"
  • Bearberry, an English rendering of the Latin
  • Other common names include Arberry, Bear's Grape, Crowberry, Foxberry, Hog Cranberry, Kinnikinnick, Mealberry, Mountain Box, Mountain Cranberry, Mountain Tobacco, Red Bearberry, Sagakomi, Sandberry, Upland Cranberry, Uva-Ursi, Melbær, Mjølbær (Nor), Hede-Melbærris (Dan), Sianpuolukka (Fin), Sortulyng (Is), Immergrüne Bärentraube (Ger), Grainnseag (Gaelic)

Taxonomy:

  • Kingdom Plantae, the Plants
    • Division Magnoliophyta, the Angiosperms (flowering plants)
  • Taxonomic Serial Number: 23530
  • Also known as Arbutus uva-ursi, Arctostaphylos adenotricha, Uva-Ursi uva-ursi

Identification:

Description:

  • A prostrate, evergreen shrub with trailing stems, 2"- 8" tall.
  • Bark thin and exfoliating.
  • Leaves dark green, leathery, 1/2"-1" long, like a spatula in form, being rounded at the apex and tapering gradually towards the base to a very short stalk. Edge smooth and slightly rolled back, the young leaves fringed with short hairs. Upper surface dark, shining green, the veins deeply impressed, the lower side a paler green, with the veins prominent and forming a coarse network. No distinctive odor, but a very astringent and somewhat bitter taste.
  • Flowers rose/white, bell shaped, and borne in terminal racemes.
  • Fruit bright red berrylike drupes, 1/4"-1/2" in diameter; each containing five (sometimes four) individual nutlets.
  • Stems trailing, much-branched, short, and woody; covered with pale brown bark, scaling off in patches, and forming thick masses, 1'-2' long. The long shoots rise obliquely from the stems for a few inches and are covered with soft hairs.
  • Roots can extend to a depth of 4'-6'.
  • Chief constituent of Bearberry leaves is a crystallizable glucoside named Arbutin. Other constituents are methyl-arbutin, ericolin (an ill-defined glucoside), ursone (a crystalline substance of resinous character), gallic acid, ellagic acid, a yellow colouring principle resembling quercetin, and probably also myricetin. Tannin is present to the extent of 6%-7%.

Distribution:

  • Northern Europe; Northern North America, south in mountains

Habitat:

  • Often a dominant understory species in open pine forests under Jack Pine (Pinus banksiana), also in the understories of White Spruce (Picea glauca), Black Spruce (Picea mariana), Paper Birch (Betula papyrifera), Quaking Aspen (Populus tremuloides), and some eastern deciduous forests.
  • Soils: Wide range of soil textures, although commonly found on well-drained soils with relatively low amounts of clay and silt. Frequently occurs on sandy soils, shallow soils, soils on rock outcrops, and rapidly drained coarse-skeletal soils.
  • Common on dry, nutrient-poor soils. Leaves seem to be retained longer on plants growing on sandy, nutrient-poor soil than on plants growing on a site with better nutrient availability.
  • Shade-intolerant species often found in open pine forests. Grows best in high light situations and becomes very rare when shade becomes intense. In the open, forms a compact and intricate mat; under a canopy, long, thin trailing stems creep along the forest floor. Shoots are more upright under partial shade than in the open.

Fire:

  • A shade-intolerant endurer of fires that stores seed in the soil. A sprouting species best suited to short fire cycles with low fuel buildup and low fire intensities. It possesses latent buds on the horizontal stems and dormant buds on the stembase or root crown that allow sprouting of surviving plants.
  • In boreal forest, regenerates from surviving basal sprouts following fire and replaces itself at a fairly rapid rate. Reinvades burned sites from adjacent, unburned plants or by seed. The seeds have been reported to survive fire in the upper soil and be stimulated to germinate by heat from the fire.
  • When rooted in mineral soil, it can survive moderate fire. However, when rooted in organic soil layer, a fire that removes this soil will kill the plant. If the duff and soil are moist and not completely consumed by fire, some root crowns may survive. Rooted stolons under rocks, moist logs, or in other protected microsites may also survive. Bearberry plants are sufficiently resistant to ignition to inhibit fire spread in light, flashy fuels.

Associates:

  • Trees: Paper Birch (Betula papyrifera), White Spruce (Picea glauca), Black Spruce (Picea mariana), Jack Pine (Pinus banksiana), Quaking Aspen (Populus tremuloides)
  • Shrubs:
  • Herbs:
  • Ground Covers:
  • Mammals: The low-quality fruit spoils slowly, lasting through winter when other fruits are gone. Black Bear eat fruits in the autumn, but they are especially important to bears in the early spring.
  • Birds: Fruits eaten by songbirds, gamebirds, including five species of grouse and Wild Turkey.

History:

  • Native Americans used alone or with tobacco and other herbs. When mixed with tobacco, it was referred to as Kinnikinnick, from the Algonquin for "mixture." Used as a smudge or smoked in a sacred pipe, carrying the smoker's prayers to the Great Spirit.
  • Native Americans used Uva Ursi tea to treat inflammation of the urinary tract, urethritis, kidney stones, and cystitis. Cheyenne used the tea to treat back sprains. Some Native American tribes powdered the leaves and applied them to sores. Other tribes drank it to treat venereal diseases. The berries were also made into a tea that was used to ward off obesity.
  • Used in the 13th Century by the Welsh "Physicians of Myddfai," described by Clusius in 1601, and recommended for medicinal use in 1763 by Gerhard of Berlin and others. First appeared in the London Pharmacopoeia in 1788, though probably in use long before.
  • Early settlers of the Americas used the leaves taken internally as an astringent to treat nephritis, kidney stones and other diseases of the urinary system. This herb is relatively safe, however large doses may cause nausea, and it has the strange side effect of turning the urine green.

Uses:

  • Smoking the leaves as a tobacco substitute is the most widely mentioned human use of Bearberry.
  • Medical uses of Bearberry leaves were recognized by early Romans, Native Americans, and settlers. Bearberry leaves are used still used medicinally in Poland and other countries. The most important medical use of the leaves is for treating urinary tract disease. They can also be used to make a highly astringent wash and as a vasoconstrictor for the endometrium of the uterus.
  • The berrylike drupes have dry, insipid, and tasteless flesh when raw but are useful emergency food. Native Americans fried them or dried them and used them in pemmican. The fruit is also used in jelly, jam, and sauces.
  • In Scandinavia, Bearberry is used commercially to tan leather.

Reproduction:

  • Reproduction primarily asexual. After the second year, the stems (stolons) produce adventitious, feeding roots at the nodes which seldom grow deeper than the duff layer. If a stem is severed from the original plant, roots develop which penetrate into mineral soil. When plants are growing in sandy soil or loose duff, the creeping stems often grow under the surface. The resulting clonal pattern is generally compact.
  • Seed: The berrylike red drupes persist on the plants through winter and are dispersed by animals and gravity. Seeds have hard seedcoats and dormant embryos, and may be stored in the soil. Seedling growth is slow for the first 3 years, then increases. During the first year, root growth exceeds shoot growth. Bearberry plants which originated naturally as seedlings appear to be rare.
  • Flowers waxy-looking, in small, closely-crowded, drooping clusters, of 3-15 flowers, at the ends of the preceding year's branches, appearing in early summer, May-June, before the young leaves. The corolla, about 2/3" across, is urn-shaped, reddish white or white with a red lip, transparent at the base, contracted at the mouth, which is divided into four to five short reflexed, blunt teeth, which are hairy within. There are ten stamens, with chocolate-brown, awned anthers.
  • The berry, which ripens in autumn, is about the size of a small currant, very bright red, smooth and glossy, with a tough skin enclosing an insipid mealy pulp, with five one-seeded stones.
  • Largely wind pollinated.

Propagation:

  • By seed, scarification and stratification are required -- The embryos are dormant and surrounded by a hard seed coat. They can remain viable for 3 years. Scarification with acid is usually necessary, the amount of time being variable for the seed. This is then followed by warm and cold stratification.
  • Stem cuttings taken in the fall are described as the best method of establishment. Propagation by root cuttings has been done successfully. Good seed crops occur at 1 to 5 year intervals. Seedling establishment is difficult and time consuming. Seed is available commercially.

Cultivation:

  • Prefers sandy or gravelly soil.
  • Useful in erosion control plantings. Well suited to coarse-textured soils low in nutrients. Growth is good on gentle to steep sites.
  • Attractive garden ground cover on sunny, sandy banks, along rock walls, and other sunny places in urban areas.
  • Moderately drought resistant.
  • Branches with fruit are used for fall and Christmas decorations.
  • Available from nurseries.
  • Propagation by layering or rooted cuttings is relatively easy.

Links:

Boreal border
Last updated on 1 August 1999