Johnson and Wilson, Juncus edgariae (Juncaceae) 
401 
Distribution and habitat: Endemic to New Zealand (North Island, South Island, 
Stewart Island, Kermadec Islands, and Chatham Islands), at altitudes ranging from sea 
level to 1000 m; in damp, often disturbed, open areas such as roadside ditches, 
pastures and margins of swamps, in soils ranging from sandy to clay-loam. This is the 
most widely occurring and abundant of the 'leafless' rush species in New Zealand 
according to Healy and Edgar (1980: 98, as /. gregiflorus), who also comment that it is 
the most weedy of the native species in this group. This situation is similar to that in 
Australia, where many of the native Juncus species seem to have spread much more 
widely thanks to human disturbance in the last two centuries (Johnson 1991), and 
some are considered weedy in pastures (commonly in those that are over-grazed). 
Introduced to Great Britain in wool shoddy, but probably not persistent there. 
Notes: This common New Zealand species was formerly included in the concept of 
J. gregiflorus L. Johnson, which is here considered to be restricted to Australia. Records 
of J. gregiflorus in New Zealand (e.g. Edgar (1970), Healy (1970), Healy and Edgar 
(1980)) and most or possibly all wool shoddy records under that name in Great Britain 
refer to this new species.This species is also morphologically similar to the New 
Guinean J. durus L. Johnson & K.L. Wilson, ined. (Wilson and Johnson, this issue). All 
three species have tough culms with dense pith (variously interrupted) and loose 
cataphylls that are dark golden brown both abaxially and adaxially. 
In the Flora of New Zealand (vols 2 and 3; Edgar 1970, Healy and Edgar 1980) and in 
Healy (1970), this species would key to J. gregiflorus. 
Juncus edgariae differs from /. gregiflorus sens, strict, in having culms that are more 
yellow-green and shinier when dried, with the pith in the culms denser and less 
interrupted, with the lacunae in the pith more or less circular to longitudinally 
ellipsoid in shape. Capsules are usually darker golden brown at maturity. The new 
species also tends to have the abaxial brown colour of the cataphylls extending higher 
towards the stramineous apex and tapering off more gradually than in /. gregiflorus. 
J. durus and J. gregiflorus differ from J. edgariae in having finer culm striations (c. 0.05 mm 
wide) that are all similar (in the latter, the striations are mostly broader (to c. 0.1 mm 
wide) but mixed with some finer as well).The pith in /. edgariae culms has smaller 
lacunae than in J. durus, while the pith in /. gregiflorus differs from both in being 
usually much more reduced: to mere septa-like plates of pith separating very large 
lacunae. The pith of /. edgariae is illustrated in Healy (1970: fig. 34, as J. gregiflorus), both 
a section that has partly continuous pith (presumably from near the apex of a culm) 
and also a more typical section with irregular gaps. 
Sykes (1977: 180) discussed the occurrence of the species on the volcanic Kermadec 
Islands, where he considered it to be native on Raoul Island. Specimens seen from 
there have consistently small flowers (outer tepals only 2.0-2.2 mm long), but 
occasional specimens from other areas also have smallish flowers. The significance of 
this needs further study in the field - it may be the consequence of a limited genetic 
base in the Raoul Island population. 
The species is named for Dr Elizabeth Edgar of Christchurch, who has contributed so 
greatly over many years to systematic knowledge of numerous monocot groups in 
New Zealand, including this family and particularly the genus Luzula, which she has 
also studied in Australia. 
Selected collections examined: NEW ZEALAND: North Island: Lake Tutira, Braggins, Feb 1967 
(WELTU); Moanatuatua Swamp, S of Hamilton, Briggs, 31 Jan 1966 (CHR, NSW 90828); Kaiaka, 
Carse K14, 25 Dec 1913 (K); Wallaceville, Upper Hutt, Harris, 12 Aug 1944 (CHR 83485,83488, NSW); 
Awanui, Northland, Johnson 7499, 15 Nov 1971 (CHR, NSW); Merchant Ridge, Tararua Range, 
McNeill-Adnms, Jun 1968 (WELTU); Tangitaroria, 12 miles [19 km] ENE of Dargaville, Hobson 
County, Melville 5187 and Moore, 6 Nov 1961 (CHR, K, NSW); Manukau County, c. 10 miles [16 km] 
ESE of Clevedon, Orchard 3284,25 Apr 1972 (AK, K, NSW); Bunnythorpe, Zotov, 6 Mar 1930 (CHR 
3611, NSW). 
