Schoenoplectus lacustris

Growing form

Perennial herb, which forms extensive stands.

Size

1–3 m high.

Stem

The stem is dark green, mostly afoliate, terete, smooth, rigid, 0.5–1 cm thick and with spongy continuous pith. The rhizome is horizontal and robust.

Leaf

The leaves are at the base of the stem. The leaves are sheathed, typically without a lamina or with a short lamina. (In flowing water the lamina can be long and flat). The sheaths are yellowish brown or maroon. The lowest bract of the inflorescence is like an extension to the stem. The bract is as long as the inflorescence or often longer.

Flower

The branches inflorescence is at the summit of a stem. It consists of 15–25 spikes. The primary branches of the inflorescence are typically more than 3 cm long. The spikes are 5–12 mm long and arranged individually or in clusters of few. The bisexual flowers are at the axils of scales. The scales are brown, smooth and lustrous. There are three stamens and a gynoecium with three stigmas in a flower.

Fruit and seed

The fruit is an obtusely triangular achene (2.5–3 mm).

Source: Pinkka e-learning: Botanical excursion to Lammi - Hazel grove and herb-rich forest vegetation by the lake Pääjärvi, herb-rich forest slope on the hill Linnavuori. CC BY 4.0

The map represents observations of this taxon, but it may not be used as a distribution map.

squares
Observations
  • Total squares
Checklist
MR.1
Scientific name
Schoenoplectus lacustris
Author
(L.) Palla
Vernacular names
  • järvikaisla (Finnish)
  • säv (Swedish)
Identifier
http://tun.fi/MX.40249
Taxon rank
Occurrence in Finland
Status in Finland
Regulatory Status
Finnish Regional Red List Category
  • 2019
  • 2010
Experts
  • Pertti Uotila
  • Heikki Toivonen
DNA barcode sequences
Schoenoplectus lacustris
13 public records
Informal groups
  • Vascular plants
  • Plant life forms
  • Aquatic plants
  • Helophytes