Carex L.
Perennial herbs, tufted, rhizomatous or stoloniferous. Stems usually 3-angled and solid, rarely terete and hollow. Leaves tristichous, usually linear, mostly crowded at base of stem and sheathing, sheath closed, with a minute, membranous ligule. Plants usually monoecious, rarely dioecious. Inflorescence a spike, cluster of spikes, or panicle; bracts leaf-like or setaceous. Spikes sessile or pedunculate, unisexual or bisexual, composed of numerous 1-flowered spikelets, each subtended by a glume. Flowers unisexual, perianth 0. Male flower with 3 stamens (rarely 2). Female flower a single pistil enclosed in an utricle; style 1, branched above to 2 or 3 stigmas projecting from utricle. Nut trigonous or biconvex, enclosed within persistent utricle. A genus of 1500-2000 spp. in cold and temperate regions or at high altitudes in the tropics. Native spp. 73, adventive 22.
SYNOPSIS
- I. Subgenus VIGNEA.
- Spikes several to numerous, all ± similar, sessile, usually bisexual. Stigmas 2.
- A.
- Male flowers above female in each spike
- 1. Section DIVISAE.
- Spikes several in an oblong or ovate ebracteate head. Utricles shining, strongly nerved. Rhizome far-extending:
- 1. *divisa
- 2. Section ARENARIAE.
- 3. Section BRACTEOSAE.
- Spikes few in a cluster with leaf-like bracts. Utricles minutely papillose:
- 20. pterocarpa, 24. trachycarpa
- 4. Section MULTIFLORAE.
- Spikes numerous in a spiciform panicle; lower bracts long, setaceous. Utricles yellowish-green. Leaf-sheaths transversely rugulose:
- 10. *vulpinoidea
- 5. Section PANICULATAE.
- Spikes numerous in a ± contracted ebracteate panicle. Utricles reddish-brown, margins strongly scabrid above:
- 7. *paniculata, 11. appressa, 13. diandra, 22. secta, 23. sectoides, 25. virgata
- 6. Section MUEHLENBERGIANAE.
- Spikes often rather few, ± distant; bracts small. Utricles greenish, glabrous, not nerved:
- 2. *divulsa, 4. *muricata, 9. *spicata
- 7. Section STENORHYNCHAE.
- Spikes numerous in a ± branched, spiciform panicle; bracts small. Utricles brown, many-nerved:
- 5. *otrubae
- B.
- Female flowers above male in each spike
- 8. Section INVERSAE.
- 9. Section OVALES.
- 10. Section STELLULATAE.
- Spikes several, rarely unisexual, often slightly distant; bracts filiform. Utricles spreading stellately when mature:
- 14. echinata
- 11. Section CANESCENTES.
- Spikes few in an ebracteate cluster. Utricles scarcely beaked:
- 18. lachenalii
- II. Subgenus CAREX.
- Spikes (1)-several, often peduncled, usually unisexual, upper male spikes differing markedly from lower female ones. Stigmas 3 or 2.
- 12. Section ELATAE.
- Spikes several, lower often pendent, ± distant, long-peduncled. Utricles glabrous; beak long, deeply bidentate. Stigmas 3. Leaves wide:
- 31. *iynx, 32. *longebrachiata, 41. cockayniana, 43. elingamita, 46. forsteri, 50. kermadecensis, 55. spinirostris
- 13. Section TUMIDAE.
- Spikes several, erect, upper ± sessile, ± approximate, lower distant, ± peduncled. Utricles inflated, many-nerved; beak shortly bidentate. Stigmas 3:
- 27. *brownii
- 14. Section SYLVATICAE.
- Spikes several, lax-flowered on long slender peduncles. Utricles light greenish to light brown, glabrous, ± nerveless; beak long, bidentate. Stigmas 3:
- 37. *sylvatica
- 15. Section MITRATAE.
- Spikes few, ± lax-flowered. Utricles pubescent; beak short. Stigmas 3. Leaves usually narrow:
- 38. breviculmis
- 16. Section CAPITELLATAE.
- Spike solitary. Utricles membranous; beak very short. Stigmas 3:
- 39. capillacea
- 17. Section SPIROSTACHYAE.
- Spikes few, dense-flowered, ± approximate, sessile. Utricles many-nerved, glabrous, yellow-green; beak long, curved, bifid. Stigmas 3. Leaves narrow:
- 28. *demissa, 45. flaviformis
- 18. Section PSEUDOCYREREAE.
- Spikes several, dense-flowered, subsessile, lower ± remote, ± peduncled. Glumes small, hyaline, margins fimbriate. Utricles ± inflated, glabrous, closely many-nerved, greenish; beak long, deeply bidentate. Stigmas 3. Leaves conspicuously septate-nodulose:
- 44. fascicularis, 52. maorica
- 19. Section PHYSOCARPEAE.
- 20. Section PALUDOSAE.
- Spikes several, sturdy, dense-flowered, erect, pedunculate. Utricles long, ± corky, glabrous, ± inflated, beak short. Stigmas 3. Leaves ± septate-nodulose:
- 26. *bichenoviana, 36. *riparia, 53. pumila, 58. trifida
- 21. Section HIRTAE.
- Spikes several, dense-flowered, erect. Utricles hairy, long, many-nerved, ± inflated; beak short or long. Stigmas 3. Leaves hairy, ± septate-nodulose:
- 30. *hirta
- 22. Section MAXIMAE.
- Spikes several, dense-flowered, distant, pedunculate. Utricles glabrous; beak short. Stigmas 3:
- 35. *pendula
- 23. Section TRACHYCHLAENAE.
- Spikes several, dense-flowered. Glumes purplish or black. Utricles papillose (or puberulous); beak very short, ± entire. Stigmas 3:
- 29. *flacca
- 24. Section PACHYSTYLAE.
- Spikes few, dense-flowered, ± approximate. Utricles glabrous (or pubescent); beak absent or minute. Stigmas 3. Leaf sheaths often pubescent:
- 34. *pallescens
- 25. Section ACUTAE.
- Spikes several, in clusters of 2-5 or singly from each node, erect or pedunculate, dense-flowered. Utricles glabrous; beak absent or minute. Stigmas 2:
- 42. coriacea, 47. gaudichaudiana, 48. geminata, 51. lessoniana, 54. sinclairii, 56. subdola, 57. ternaria
- 26. Section ECHINOCHLAENAE.
- Spikes few to several, dense-flowered, erect, upper usually ± approximate, sessile, lower more distant, pedunculate. Utricles coriaceous, margins often scabrid; beak short. Stigmas 2 or 3. Leaves usually narrow, often reddish, tips sometimes curled: nos. 59-91, 33 native spp.
- III. Subgenus PRIMOCAREX.
- Spikes solitary, terminal, bisexual or unisexual. Rhachilla often present within utricle. Stigmas 2 or 3:
- 92. acicularis, 93. allanii, 94. enysii, 95. pyrenaica var. cephalotes
(Leaves V-shaped in cross-section are here described as channelled; leaves shaped in cross-section like an inverted W are described as double-folded)
Key
Most spp. flower between November and January and fruit matures between January and March. In the key and in descriptions, the measurements and colour given for female spikes and utricles refer to mature organs.
Smith and Faulkner (Bot. Rev. 42, 1976, 53-81) have summarised recent work on the morphology of the Carex inflorescence. In their view the morphological unit in Carex functioning as the female flower is actually a one-flowered spikelet subtended by a glume; the true female flower is a single gynoecium enclosed in an utricle. The morphological unit in Carex functioning as a male flower comprises 3 stamens in the axil of a glume. Evidence suggests that this is a condensed spikelet of three single-stamened flowers rather than a single male flower. Hence the spikelet-like flower-clusters in Carex which superficially resemble the spikelets of grasses are morphologically spikes, and composed of numerous spikelets which resemble single flowers.
Some species of Carex are weeds of varying significance in grassland and wet places. Reproduction is by "nuts", sometimes by rhizomes. Fruits lack characters assisting dispersal, most falling close to the parent plants: longer distance dispersal sometimes occurs when fruit is carried on animal coats, in mud in hooves, by run-off water on slopes, or in drains and streams.
It is probable that the adventive spp. came as impurities in agricultural seed from Europe, N. America or Australia, with the exception of C. pendula which is grown as an ornamental. Recent frequent proposals to import variegated forms of Carex could result in the finding of additional species in the adventive state in the future if authority is granted and such material escaped from cultivation. In the way potentially troublesome rhizomatous species, such as C. riparia, could achieve entry, either intentionally or accidentally as misidentified material. It appears that variegated forms of the tufted Japanese C. morrowii Boott have been in horticulture here for several decades, but have shown no tendency to escape as yet.
In the synopsis given below, spp. are arranged under sections mainly following Kükenthal's monograph (Pflanzenreich 38, 1909, 67-767). Most of the adventive spp. belong to sections which have no native representatives - sections Divisae, Multiflorae, Muehlenbergianae and Ovales (in subgenus Vignea) and sections Tumidae, Sylvaticae, Hirtae and Pachystylae (in subgenus Carex). We have chosen the most convenient arrangement of subgenera and placed Vignea first so that the two groups of adventive spp. do not fall too far apart in the text. Again for convenience, the 33 native spp. belonging to section Echinochlaenae of subgenus Carex are placed in an alphabetical series following the other 21 native spp. which belong to other sections of subgenus Carex.
Carex canescens var. robustior was recorded for N.Z. by Akiyama (J. Fac. Sci. Hokkaido Imp. Univ. ser. 5, 2, 1932, 74). This was presumably a misidentification and no specimens have been found.
Two further apparently adventive spp. (subgenus Carex) have been collected but have not yet been identified. One from swampy land at Hokitika with general aspect of Paspalum - A. J. Healy 61/130, 2.2.1961 (CHR 123016) and A. E. Esler, 30.12.1968 (CHR 284141) - is a tall, red-leaved plant with ± pendent, distant spikes, 3 style-branches and broadly ovate glumes < faintly nerved, red-brown utricles. The second undetermined sp. has been collected from Waipoua - W. Silvester, Dec. 1963 (CANU 9678), and from North Cape Scenic Reserve-A. E. Wright 871, 21.11.1975 (CHR 284148). The plants are light green with shoots bulbous at base, upper spikes approximate and erect the lowermost more distant, style-branches 3, glumes light brown to whitish, emarginate, ± ½ length of distinctly nerved, greenish-brown utricles.
Moore and Edgar (Fl. N.Z. 2, 1970, 284) noted that there might be an unnamed indigenous calcicolous sp. in Nelson, and gave a brief description. Mr A. P. Druce has made further collections of this sp. (which belongs to subgenus Carex section Echinochlaenae) and considers (pers. comm.) that the 2-styled plants are also distinct and more closely related to C. wakatipu. He has also found much larger 3-styled plants with distant spikes growing in scrub on marble cliffs at Takaka Hill, N.W. Nelson.