Download Polygonaceae

Rumex beringensis Jurtzev & V.V. Petrovsky
Polygonaceae
Synonyms: Rumex graminifolius auct. non Rudolph ex Lamb.
Global Distribution:
Amphi-Beringian.
Alaska Distribution:
Bering Tundra, Bering Taiga, Aleutian Meadows,
Alaska Range Transition, Coast Mountains Transition.
Ecoregions Occupied: Bering Sea Islands, Bristol Bay Lowlands, Alaska
Peninsula, Lime Hills, Alaska Range, Kluane Ranges.
Conservation Status:
S3 G3.
Description
Inner tepals 1.6 to 2.3 mm
long
Inflorescences occupying more than
the upper half of stems, dense towards
top
Inflorescences interrupted
near base, branches ascending
Basal leaves linear or
spatulate-lanceolate, 1.5 to
5 cm long, 1 to 3 mm wide,
lacking basal lobes
Stipules brown or red –brown,
membranous
Illustration by Matthew L. Carlson
2 cm
Basal leaves gradually
narrowing to long petioles
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Rumex beringensis
General:
Perennial herb from thick, densely tufted underground
stolons, dioecious; stems several, erects or rarely ascending,
branched in the inflorescence, 5 to 15 cm tall; shoots usually
densely crowded.
Leaves:
Basal leaves arranged in rosettes, linear or spatulatelanceolate, lacking basal lobes, 1.5 to 5 cm long, 1 to 3 mm
wide, bases gradually narrowing to long petioles, entire;
stipules fused to form sheaths, brown or red-brown,
membranous; stem leaves few, reduced.
Flowers:
Inflorescences terminal, occupying more than upper half of
stems, dense towards top, usually interrupted near the base;
branches ascending; pedicels 1 to 4 mm long; flowers 4 to 7
in whorls, usually unisexual; inner tepals distinctly enlarged,
1.6 to 2.3 mm long, 1.8 to 2.5 mm wide.
Fruits:
Achenes brown or red-brown, 1 to 1.5 mm long, 0.8 to 1.2
mm wide.
© Forrest Baldwin 2006
272
Rumex beringensis
Ecology
Elevation:
Known from near sea level to 1,720 m in Alaska;
occurrences over 1,000 m elevation are located in the
western Alaska Range, Wrangell Mountains, and St.
Elias Mountains.48
Landform:
Alpine slopes, alpine ridges, recently de-glaciated areas,
late melting snow beds, ephemeral ponds, lake shores,
stream banks.48
Soil Type:
Sand, volcanic ash, silt, gravel, alluvial deposits; often
on volcanic substrates.48
Moisture regime:
Moist to wet.
Slope:
Flat to steeply sloped.
Aspect:
No particular aspect.
Vegetation type:
Sparsely vegetated, alpine cushion vegetation,
graminoid-forb tundra, graminoid meadow, dwarf birchericaceous heath, dwarf shrub-ericaceous tundra, mosslichen mats.
Associated species:
Achillea millefolium, Angelica lucida, Arabidopsis
kamchatica, Arctous alpina, Armeria maritima,
Calamagrostis canadensis, Chamerion latifolium,
Festuca brachyphylla, Festuca rubra, Heuchera glabra,
Leymus mollis, Lupinus nootkatensis, Oxyria digyna,
Rhododendron lapponicum, Salix glauca, Trisetum
spicatum.
Longevity:
Perennial, likely long-lived as some individuals form
extensive, dense tufts.
Phenology:
Flowering begins early June, probably sooner; fruiting
through mid-September.
Population estimate:
There are 33 known occurrences in Alaska; locally
common at several locations, one of which consists of
approximately 1,000 individuals; sometimes occurs in
pure stands.
Reproductive Biology: Dioecious plants are obligately outcrossing because they
bear flowers of one sex; likely wind-pollinated.
Similar Species
Material from Alaska corresponding to Rumex aureostigmaticus, Rumex krausei,
and Rumex beringensis has in the past been assigned to Rumex graminifolius,
which is known from northern Fennoscandia to southeastern Yakutia. Rumex
graminifolius is not known from or likely to occur in Alaska. Rumex
aureostigmaticus, Rumex krausei, and Rumex beringensis are similar and likely to
be confused with one another, although they are somewhat separated
geographically. All three species can occur in similar habitats.
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Rumex beringensis
The table below describes the differences in morphology and geographic range
between the three aforementioned Rumex species and the non-native Rumex
acetosella.
Stipules
Inflorescences
Inner
Tepals
Range
Rumex
beringensis
Brown or
red-brown,
membranous
Inflorescences
interrupted at base,
dense near top,
occupying more
than the top half of
stem, never globose
1.6 to 2.3
mm long
Southwest Alaska
and Wrangell
Mountains
Rumex
aureostigmaticus
Whitish,
often
becoming
tattered into
narrow
segments
Inflorescences
diffuse with
straight, slender
branches
2 to 2.6
mm long
Arctic Alaska
2.3 to 3
mm long
Northwest Alaska
and St. Lawrence
Island
1.2 to 1.7
mm long
Anthropogenically
disturbed areas
throughout Alaska
Species
Rumex krausei
Brown or
red-brown,
membranous
Rumex
acetosella
Brown at
base, silvertinted and
lacerated in
upper half
Inflorescences
dense, sparsely
branched or
unbranched,
occupying usually
less than top half of
stem, compact or
globose when
young
Inflorescences
diffuse and
interrupted
throughout,
branched
2 cm
ALA 142009
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