Burke: Potamogeton pulcher vs. Potamogeton praelongus

	Potamogeton pulcher	Potamogeton praelongus
		white-stalked pondweed, whitestem pondweed
Habit		Aquatic, herbaceous perennials from slender rhizomes, the stems up to 3 m. long, sparingly branched, slightly flattened, 2-3 mm. thick, whitish, the shorter internodes zigzag.
Leaves		Leaves all submersed, the blades sessile, with a clasping base, oblong-lanceolate, 1-2.5 dm. long and 2-3 cm. broad, entire, the tip rounded and somewhat hooded; stipules free of the blade, 4-10 cm. long, whitish.
Flowers		Flowers perfect, in dense spikes 2.5-5 cm. long; peduncles club-shaped, 1-3 dm. long; perianth of 4 clawed segments, each with an upturned, oval blade; stamens 4, fused with the claws; pistils 4, sessile.
Fruits		Achenes obovoid, 4-5 mm. long, with a short beak and prominent dorsal keel.

	Potamogeton pulcher	Potamogeton praelongus
Flowering time		May-July
Habitat		Deep water of lakes.
Distribution	[WildflowerSearch map] [BONAP county map]	Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, Great Plains, Great Lakes region, and eastern North America. [WildflowerSearch map] [BONAP county map]
Origin		Native
Conservation status		Not of concern
Sibling taxa	P. alpinus, P. amplifolius, P. berchtoldii, P. crispus, P. epihydrus, P. fibrillosus, P. foliosus, P. friesii, P. gramineus, P. illinoensis, P. natans, P. nodosus, P. obtusifolius, P. praelongus, P. pusillus, P. richardsonii, P. robbinsii, P. strictifolius, P. zosteriformis	P. alpinus, P. amplifolius, P. berchtoldii, P. crispus, P. epihydrus, P. fibrillosus, P. foliosus, P. friesii, P. gramineus, P. illinoensis, P. natans, P. nodosus, P. obtusifolius, P. pusillus, P. richardsonii, P. robbinsii, P. strictifolius, P. zosteriformis
Web links	Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Potamogeton pulcher

Potamogeton praelongus

white-stalked pondweed, whitestem pondweed

Habit

Aquatic, herbaceous perennials from slender rhizomes, the stems up to 3 m. long, sparingly branched, slightly flattened, 2-3 mm. thick, whitish, the shorter internodes zigzag.

Leaves

Leaves all submersed, the blades sessile, with a clasping base, oblong-lanceolate, 1-2.5 dm. long and 2-3 cm. broad, entire, the tip rounded and somewhat hooded;

stipules free of the blade, 4-10 cm. long, whitish.

Flowers

Flowers perfect, in dense spikes 2.5-5 cm. long;

peduncles club-shaped, 1-3 dm. long;

perianth of 4 clawed segments, each with an upturned, oval blade;

stamens 4, fused with the claws;

pistils 4, sessile.

Fruits

Achenes obovoid, 4-5 mm. long, with a short beak and prominent dorsal keel.

Potamogeton pulcher

Potamogeton praelongus

Flowering time

May-July

Habitat

Deep water of lakes.

Distribution

[WildflowerSearch map]

[BONAP county map]

Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, Great Plains, Great Lakes region, and eastern North America.

[WildflowerSearch map]

[BONAP county map]

Origin

Native

Conservation status

Not of concern

Sibling taxa