Species: Sparganium hyperboreum Laestad.

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Sparganium hyperboreum Laestad.

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TAXONOMY

Family:

Sparganiaceae

Genus:

Sparganium

Species Synonyms:

Sparganium submuticum (Hartm.) Hartm.
Sparganium williamsii Rydb.

Common Names:

northern bur-reed

DISTRIBUTION

Canada:

Yukon – Mackenzie District – Keewatin District – Ungava – Labrador, south to west-central British Columbia, northwestern Saskatchewan, northeastern Manitoba, northwestern Ontario, eastern Quebec – Newfoundland

Saskatchewan:

northwestern Saskatchewan; Lake Athabasca

Ecoregion:

Tazin Lake Upland

HABITAT

Saskatchewan:

emergent shallow-water aquatics at sedge-marshy streamlet borders

Canada:

ponds and lakes

RARITY STATUS

Provincial Status According
to Harms (2003):

Endangered

Nature Conservancy Status:

G5 S2

Saskatchewan Species at
Risk Status:

None

COSEWIC Status:

None

Northern bur-reed is endangered because of extreme rarity in Saskatchewan. It is regionally restricted to the northwest corner of the province and is almost always locally sparse. Immediate or probable threats have been identified.

SPECIES DESCRIPTION

Height:

10 – 30 cm

Roots:

fibrous

Stems:

slender, grass-like, weak

Leaves:

usually floating, 10 – 50 cm long, 2 – 4 mm wide, linear, flat

Inflorescence:

male heads 1, terminal, continuous with uppermost female head; female heads 1 – 4, axillary, sessile or lower ones short-stalked, about 1 cm broad at maturity; central axis unbranched, flexuous; bracts ascending, lower bracts inflated near base

Flowers:

tepals without dark spot at tip, margin jagged; stigmas 1

Fruits:

single-seeded, 1.5 – 2.5 mm, brown or yellowish, dull, ribbed, beakless or nearly so

SPARGANIUM KEY FOR SPECIES FOUND IN SASKATCHEWAN

1 Stigmas 2; fruits sessile, to about 8 mm thick, broadly inversely pyramidal; leaves to 12 mm wide	S. eurycarpum
1 Stigmas 1; fruits more or less stalked, to about 3 mm thick, ellipsoid; leaves 2 – 20 mm wide	2

2 Fruits beakless or beak less than 1.5 mm; male heads 1	3
2 Fruits conspicuously beaked, up to 6 mm long; male heads usually 2 or more	5

3 Fruits beakless; leaves 1 – 5 mm wide, often yellow	S. hyperboreum
3 Fruits with beaks up to 1.5 mm long; leaves 2 – 20 mm wide, green	4

4 Terminal male head remote; leaves thin, 2 – 8 mm wide	S. natans
4 Terminal male head not remote from female heads; leaves thicker, to 2 cm wide	S. glomeratum

5 Sepals inserted on the middle of the stalk and rarely reaching middle of fruit	S. fluctuans
5 Sepals inserted at the top of the stalk and commonly exceeding the middle of fruit	6

6 Beak of fruit as long as the body; sepals appressed; leaves erect or ascending	S. chlorocarpum
6 Beak of fruit shorter than body; sepals ascending or spreading; leaves submersed or floating	7

7 Leaves 2 – 5 mm wide, rounded on the back; female heads 1 – 2 cm broad	S. angustifolium
7 Leaves to 5 – 12 mm wide, flat and ribbon-like; female heads > 2 cm broad	S. multipedunculatum