– slender-leaved pondweed, western pondweed, threadleaf-pondweed
Distribution: Only known from Whatcom County in Washington; Alaska south to California, east to the Rocky Mountains; east across Canada to the Atlantic Coast and Greenland.
Habitat: Lakes, ponds, slow moving waters.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
– fennel-leaved pondweed, sago pondweed, sago-pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Shallow to deep, fresh to brackish water.
Origin: Native
Flowers: July-September
Growth Duration: Perennial