categoryZGrasses Grasses List 

LESSER POND-SEDGE

Carex acutiformis

Sedge Club- & Spike-Rush Family [Cyperaceae]

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category
category8Grasses
status
statusZnative
flower
flower8brown
flower
flower8orange
inner
inner8cream
type
typeZspiked
stem
stem8triangular
sex
sexZmonoecious

8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
Forms tufts or tussocks. Growing to 1.5m it is actually slightly taller than the 1.3m height of Greater Pond-Sedge. But it does have smaller spikes than does Greater Pond-Sedge.


8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
The inflorescence reaches higher than most leaves, but is usually topped by the lowest bract.


8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
Male inflorescences on top, Female spikes thinner and below them. The leaves are up to 1.6m long by 7 to 10mm wide and glaucous. The inflorescence has 2 or 3 purple-brown male spikelets between 1 and 4cm long atop with bluntish purple-brown, oblong glumes 5 to 6cm long.


8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
Male inflorescence. The bract to emerge from the lowest part usually reaches higher than the inflorescence. The inflorescence has 2 or 3 purple-brown male spikelets between 1 and 4cm long atop with bluntish purple-brown, oblong glumes 5 to 6cm long.




8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
These infloresences are not yet ripe, their anthers and stigmas still to emerge. Here there are at least 3 male spikes, and below them 3 thinner and longer female spikes, although their numbers vary.

The inflorescence has 2 or 3 purple-brown male spikelets between 1 and 4cm long atop with bluntish purple-brown, oblong glumes 5 to 6cm long.

The 3 to 4 female spikelets below are between 2 to 5cm long all fairly closely spaced and between 2 to 5cm long by 5 to 8mm wide - with often male florets at their tips!. The female glumes are 4 to 5mm long, purple-brown.

The long leaf-like bracts (lower half of photo) are supposed to be longer than the inflorescence...



8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
Male spikes, here very dark-brown. Some seem to take on a triangular cross-section. The top part of a female spike is below. They too are not yet ripe. The lowest bracts are usually taller than the top of the inflorescence, as here with the one on the left and the one in the right is not far off...


8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
Male inflorescences.


8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
Male inflorescence, a little damaged showing the anthers, pale-green at first.


8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
The male spikes will turn a striking orange in another month or so.


8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
A female spike. Much thinner initially, but also longer.

The 3 to 4 female spikelets below are between 2 to 5cm long all fairly closely spaced and between 2 to 5cm long by 5 to 8mm wide - with often male florets at their tips!.

The leaves have a V-groove down their centreline and some ridges either side for added stiffness. They feel rough to the touch.



8th April 2017, St. Helens Canal, Blackbrook basin. Photo: © RWD
Female spike, as yet unripe. The female glumes are 4 to 5mm long, purple-brown, quite narrow and sharply pointed, looking a bit like fountain pen nibs.


Not to be semantically confused with : Pondweeds (Potomogeton) species, of which there are many [a plant with similar name]

Hybridizes only rarely with : Greater Pond-Sedge (Carex riparia) Also with :

  • Bladder-sedge (Carex vesicaria) to produce Carex × ducellieri which was found in South Hants in 1986
  • Slender Tufted-Sedge (Carex acuta) to produce Carex × subgracilis which has been found in scattered places in England and Wales and with flowers with both 2 and 3 stigmas on the same flowering spike.

Like Greater Pond-Sedge, Bottle Sedge, Glaucous Sedge, Starved Wood-sedge, Dotted Sedge, Sheathed Sedge and indubiatably several others - they have 3 styles (rather than 2).

It grows either in the shallower parts of ponds or beside ponds, streams, and on marshes, wet meadows or swamps. It is common throughout the lowland parts of Britain and Ireland except North and Central Scotland, South and West Ireland, and South-West England. It is native to the UK.


  Carex acutiformis  ⇐ Global Aspect ⇒ Cyperaceae  

Distribution
 family8Sedge Club- & Spike-Rush family8Cyperaceae
 BSBI maps
genus8Carex
Carex
(Sedges)

LESSER POND-SEDGE

Carex acutiformis

Sedge Club- & Spike-Rush Family [Cyperaceae]