Potamogetonaceae: Pondweed Family

Crisp-leaved Pondweed – Potamogeton crispus

Blooms:

July–Sept

Plant Height:

Stems < 90 cm

Flower Size:

Medium

Origin:

Eurasia

Invasive?

Yes – moderate

Habitat:

Shallow water, ponds

Notes:

This aquatic plant is not common in Monterey County.  It would not be listed here, except that can be highly invasive.  The leaves are distinctive, 5–8 mm wide, oblong, thick and more or less wavy, with clear veins and rounded tips.

Long-leaved Pondweed – Potamogeton nodosus

Blooms:

May–Aug

Plant Height:

Stems < 300 cm

Flower Size:

Medium

Origin:

Native

Habitat:

Shallow water, lakes, ponds & streams

Notes:

This has leaves of 2 kinds, which are slightly different.  The floating leaves are 5–10 cm long, up to 5 cm wide, elliptic-lanceolate in shape, with parallel veins (typical of monocots).  Flowers are in a small, decumbent to erect spike.