Potamogeton natans

Potamogeton natans
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Alismatales
Family: Potamogetonaceae
Genus: Potamogeton
Species: P. natans
Binomial name
Potamogeton natans
L.

Potamogeton natans (broad-leaved pondweed,[1] floating pondweed,[2] floating-leaf pondweed) is an aquatic species in the genus Potamogeton native to quiet or slow-flowing freshwater habitats throughout the Holarctic Kingdom.

Description

It produces both floating and submersed leaves on the same plant. The floating leaves are ovate to oblong-ovate and almost always cordate at the base. They are dark green, leathery, opaque, with translucent longitudinal veins. They are 5 to 10 cm long, pointed at the tips, and rounded at the base.

The stipules are 4 to 17 cm long.

The submerged grass-like structures are called phyllodes, are actually modified leaf stalks.

The stems are cylindrical, without many branches, and grow from 1 to 2 metres.

The main difference between this species and other pondweeds is a discoloured flexible joint just below the top of the long leaf stalk.

The flower spikes are dense, and cylindrical. They are 5 to 10 cm long, pointed at the tip and rounded at the base. It flowers from May to September.

The fruits are 4 to 5 mm long and obovate.[3]

References

  1. "BSBI List 2007" (xls). Botanical Society of Britain and Ireland. Retrieved 2014-10-17.
  2. "Potamogeton natans". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 13 October 2015.
  3. Rose, Francis (2006). The Wild Flower Key. Frederick Warne & Co. pp. 490–491. ISBN 978-0-7232-5175-0.

External links

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