Dryas octopetala : Eight-petal Mountain Aven

Scientific Name:

Kingdom: Plantae

Division:

• Tracheophyta (vascular)
• Spermatophyta (seed bearing)
Angiospermae (enclosed seed)

Class: Dicoteldonae (two seed-leaves)

Family: Rosaceae (Rose Family)

Genera: Dryas (Mountain Avens) (Gk. Drus = Oak; referring to the resemblance of the leaves of some species to oak leaves.)

Species: octopetala (8 petalled)

Synonym(s): D.alaskensis,D.hookeriana,D.punctata,D.crenulata

English Name(s):

Eight-petal Mountain Aven, Eight-petalled Dryas, Mountain Avens

First Nation Names:

Structure:

• Low mat-forming undershrub.
• Branches freely rooting.

Leaves:

• Leathery, tardily deciduous (falling) or evergreen.
• Petioled (on a stalk).
• With stipules (appendages) rising from leaf axils, linear-lanceolate in shape, tomentose (wooly).
• Margins variable crenate, dentate, or sinuate. Never entire (smooth).
• Shape generally ovate-oblong or elliptic variable depending on subspecies.

Reproductive Parts:

• Flowers perfect (bisexual), with regular symmetry, scapose (on leafless stem), and normally solitary.
• Hypanthuim (recepticle) saucer shaped.
• Sepals and petals 8-10.
• Petals white.
• Stamens (male parts) and pistils (female parts) numerous.

Seed:

• Style persisting and becoming much-elongated and plumose in fruit.
• Fruit is an achene (nutlet).

Not to Be Confused With:

• The other Dryas (Mountain Avens). Dryas integrifolia (Entire-leaved Mountain Aven) can be distinguished by its smooth not toothed leaf margins. Dryas drummondii (Yellow-flowered Mountain Aven) can be distinguished by its yellow petals and broader leaves.

Physiology:

• Numerous subspecies have been identified for Dryas Octopetala. Divisions are based primarily on thier leaf shapes, dentation, and pubescence. Some taxonomists count many of these subspecies as seperate species. Subspecies found in Central Yukon include: D.octopetela ssp. octopetela, ssp. hookerina, ssp. alaskensis, ssp. crenulata.
• Hybridizes with D.integrifolia and between the different subspecies.
• Dryas (Mountain Avens) are superbly adapted to the rigours of the exposed areas where they grow. The tough roots are deeply anchored and their nodules contain nitrogen fixing bacteria.
• The leaves with their waxy coating and wooly undersides are designed to conserve moisture and in summer and shed ice in winter.
• The feathery styles permit wide dispersal of seeds.
• The parabolic shape of the flowers which face the sun, focuses the suns energy on the pistil (female parts) heating it up by up to 3.6 C. The warmer temperatures attract pollenating insects whose body temperatures when basking in the flowers may exceed the ambient air temperature by 5-15 C.

Life Cycle:

• Perennial

Seasonal Cycle:

• Leaves tardily deciduous (falling).
• Some leaves are evergreen and will survive the winter.
• Most plants finished blooming by mid-July.

Animal Uses:

• Reportedly harvested for food by pikas in the Southern Ogilvie Mountains.

Habitat:

• Are a pioneering species in areas recently exposed by receding glaciers.
• ssp. octopetelaand crenulata said to be found in alpinetundra.
• ssp. alaskensis said to be found in open well watered gravelly floodplains and erosion fans, rarely in tundra or rocky places.
• ssp. hookerina said to be found on snowbed slopes well above treeline.
• Liking calcareous sites.

Modern:

Industrial:

• Flowers and achene plumes (seed feathers) produce a vivid green dye.

Medicinal:

Food:

• Leaves are used for making a drink.

Traditional Gwich'in:

Folklore:

Industrial:

Medicinal:

Food:

Traditional Other:

Folklore:

Industrial:

Medicinal:

Food: