Carex binervis: Difference between revisions
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| Species: | C. binervis
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Carex binervis, the green-ribbed sedge, is a European species of sedge with an Atlantic distribution. If is found from Fennoscandia to the Iberian Peninsula and Morocco, and occurs in heaths, moorland and other damp, acidic environments. It can grow to a height of 150 centimetres (59 in), and has inflorescences comprising one male and several female spikes. The utricles have two conspicuous green veins.
Description
Vegetative parts
The culms of Carex binervis are 15–150 centimetres (6 in – 4 ft 11 in) tall,[2] although usually considerably less,[3] and triangular in section with rounded corners and often a single furrow.[2] The leaves are 7–30 cm (2.8–11.8 in) long and 2–6 millimetres (0.08–0.24 in) wide, light green and shiny on the underside, but dark green and matt on the upper surface.[2] The leaves are flat or slightly keeled, and taper abruptly to a fine point.[2]
The roots of C. binervis are 1–2 mm (0.04–0.08 in) in diameter, with the root hairs mostly occuring on the short lateral rootlets. The rhizomes run 25–40 mm (1.0–1.6 in) below the soil surface, and are light brown and approximately 6 mm (0.24 in) in diameter. The whole root system reaches a maximum depth of 18 cm (7.1 in), spreading more widely than Juncus squarrosus, another dominant plant in Atlantic wet heaths.[4]
In the vegetative state, C. binervis is difficult to distinguish from Carex bigelowii, a species which tends to grow at higher altitudes than C. binervis.[2] They differ in that C. bigelowii has glaucous leaves and purplish-brown scales on the rhizome, whereas C. binervis has orange-brown rhizome scales, and leaves which are not glaucous. The leaves of C. binervis also develop "wine-red" patches on aging, which is never seen in C. bigelowii.[2]
Reproductive parts
The inflorescence of C. binervis may be up to half the length of the stem. The lower bracts resemble the leaves, while the upper bracts are more like the glumes.[2] The inflorescence comprises a single terminal male spike, and 2–4 lateral female spikes.[2] The male spike is 20–45 mm (0.8–1.8 in) long, with purplish glumes which are 4.0–4.5 mm (0.16–0.18 in) long and have a paler midrib.[2] The female spikes are 15–45 mm (0.59–1.77 in) long and cylindrical. Their peduncles are half sheathed, and up to 10 cm (3.9 in) long, such that the lower female spikes tend to be nodding, while the upper female spikes are erect.[2]
The utricles (seeds) of C. binervis are 3.5–4.5 mm (0.14–0.18 in) long and broadly elliptical, with a rough, notched beak 1.0–1.5 mm (0.04–0.06 in) long. The plant's scientific and common names both refer to the fact that the utricles are marked with two conspicuous green veins.[2] C. binervis has a chromosome number of 2n = 74.[3]
Distribution and ecology
Carex binervis has an oceanic distribution, occurring only in areas of high rainfall, from Finland and Norway, through the British Isles, Germany, Belgium and France, to Spain, Portugal and Morocco.[5] Within the British Isles, Carex binervis has a westerly and northerly distribution, and is more abundant in the wetter countries (Scotland, Wales and Ireland) than in England.[6]
C. binervis grows in acidic, siliceous environments,[2] including "damp heaths, moors, rocky places and mountainsides";[3] together with species such as Deschampsia flexuosa, it is a "useful indicator of acid substrate".[7] The species has been recorded at altitudes of up to 930 metres (3,050 ft) on Glyder Fach in north Wales, and there are reports of occurences up to 975 m (3,200 ft) in the Scottish Highlands.[8] Although sedges are chiefly wind pollinated, insect pollinators have been observed to visit C. binervis occasionally.[9]
Taxonomy
In 1800, James Edward Smith published an article in the Transactions of the Linnean Society of London, titled Descriptions of five new British Species of Carex, which included the first descriptions of Carex davalliana, C. binervis, C. tomentosa (a synonym of C. filiformis), C. micheliana (a synonym of C. flacca) and C. laevigata.[10] After the Latin diagnosis of Carex binervis, Smith writes:[10]
This species appears to have been confounded with C. distans; and from Lightfoot's description of the green angles of the fruit, I presume it to have been what he intended under that name. It is considerably larger than the real distans, the spikes black intermixed with green rather than yellowish, and the female ones often branched or compounded at their base. Its most essential and decisive character however consists in the two strong deep-green nerves or ribs which run along each side of the fruit externally near the edge. The arillus is also broader and more compressed than in C. distans.
C. binervis is classified in Carex subsection Elatae, part of Carex section Spirostachyae, alongside C. laevigata and other species.[11] Natural hybrids are known between C. binervis and various other Carex species, including C. laevigata (forming C. × deserta), C. viridula (forming C. × corstorphinei), C. punctata and C. flava.[2]
References
- ^ "Carex binervis Sm". Proyecto Anthos. Real Jardín Botánico de Madrid. Retrieved July 3, 2011.
- ^ a b c d e f g h i j k l m A. C. Jermy, D. A. Simpson, M. J. Y. Foley & M. S. Porter (2007). "Carex binervis Sm.". Sedges of the British Isles. BSBI Handbook No. 1 (3rd ed.). Botanical Society of the British Isles. pp. 358–360. ISBN 978-0-901158-35-2.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ a b c Clive A. Stace (2010). "Carex L. – sedges". New Flora of the British Isles (3rd ed.). Cambridge University Press. pp. 951–974. ISBN 978-0-521-70772-5.
- ^ G. H. Heath & L. C. Luckwill (1938). "The rooting systems of heath plants". Journal of Ecology. 26 (2): 331–352. JSTOR 2256252.
- ^ "Carex binervis". World Checklist of Monoctyledons. Royal Botanic Gardens, Kew. Retrieved July 3, 2011.
- ^ "Carex binervis green-ribbed sedge". Wild Flowers of the British Isles. March 11, 2010. Retrieved July 3, 2011.
- ^ Clare O'Reilly & Chris Metherall (2008). "County Durham (v.c.66) & South Northumberland (v.c.67) training meeting 7th – 8th July" (PDF). BSBI News. 108. Botanical Society of the British Isles: 61.
- ^ Carex binervis, green-ribbed sedge, Online Atlas of the British and Irish Flora
- ^ Adolfo F. Muñoz Rodríguez, Inmaculada Silva Palacios & Rafael Tormo Molina (2007). "Cyperaceae and Juncaceae pollination measured in the air at two sites in SW Spain". Aerobiologia. 23 (4): 259–270. doi:10.1007/s10453-007-9072-0.
- ^ a b James Edward Smith, M.D. F.R.S. P.L.S. (1800). "Descriptions of five new British species of Carex". Transactions of the Linnean Society of London. 5 (19): 264–273. doi:10.1111/j.1096-3642.1800.tb00600.x.
- ^ Marcial Escudero & Modesto Luceño (2009). "Systematics and evolution of Carex sects. Spirostachyae and Elatae (Cyperaceae)". Plant Systematics and Evolution. 279 (1–4): 163–189. doi:10.1007/s00606-009-0156-x.
External links
Media related to Carex binervis at Wikimedia Commons- Carex binervis, West Highland Flora
