Flora of New Zealand Series

Eurybia solandri Hook. f. Fl. N.Z. 1, 1853, 119.

Type: K, "273 Colenso N.Z."

Shrub or small tree up to 4 m. tall with rather stiff, spreading, angled, viscid branchlets clad in yellowish tomentum. Lvs of young plants and reversion shoots linear-spathulate, up to 1·5 cm. long, white-tomentose below; lvs of adult plants 5-10 mm. long, linear-obovate, on petioles c. 1 mm. long, subcoriac., glab. above when mature, clad in yellowish tomentum below, margins flat to slightly revolute. Capitula up to 10 × 5-7 mm., solitary, on short branchlets; florets 8-20, of ray up to 14; phyll. in 3-4 series, ∞, forming a narrow-turbinate involucre, fulvous, viscid-pubescent. Achenes 1-1·5 mm. long, glab. or nearly so, compressed, grooved; pappus-hairs 5-6 mm. long.

DIST.: N. Coastal, occ. inland, throughout. S. Coastal to lat. 42°.

HYBRIDISM

Hybridism plays a great part in the polymorphy exhibited by Olearia in N.Z. There appears to be considerable stability among the hybrids, but few tests have been made, and no genetic work has been attempted.

The following forms have been described as spp.:

O. haastii Hook. f. Handbk N.Z. Fl. 1864, 126. Hooker's specimens from "near the glaciers of Lake Ohau, 4-4500'; Haast 761, 1863" have lvs 3 × 1·25 cm. with a petiole 5 mm. long, oblong to ovate-oblong. Hooker states that he received specimens first from Veitch of Exeter, "who cultivated it from seeds brought from New Zealand". There is a specimen from Veitch in K. Wild plants resulting from avicenniaefolia × moschata are rare, only an occ. individual being met with, and are of fairly uniform appearance. Vegetatively propagated it is common as a garden plant.

O. excorticata Buchan. in T.N.Z.I. 6, 1874, 241. Buchanan's specimens were collected in 1872 on the Tararua Range by Mitchell. Study of the area has revealed that there is a range of forms of origin arborescens × lacunosa.

O. oleifolia Kirk in T.N.Z.I. 11, 1879, 463. Kirk described his sp. from specimens collected "Ashburton, Rangitata River, and Preservation inlet". He points out its "affinities" with O. avicenniaefolia. J. B. Armstrong (T.N.Z.I. 13, 1881, 337) pointed out that similar plants in gardens had been previously known under the name O. angustata. These were propagated from plants collected by J. F. Armstrong and W. Gray in the upper Rangitata Valley in 1869. There is now known a fairly wide range of forms of the origin avicenniaefolia × odorata (some may be due to the crossing of avicenniaefolia with members of the virgata complex). O. willcoxii Petrie in T.N.Z.I. 45, 1913, 266 is another member of the group, with slender branchlets and rather distant narrow-elliptic lvs, found on Queenstown Hill, Lake Wakatipu, and neighbourhood. Petrie recognized its resemblances to Kirk's oleifolia. Several forms of the group have found their way into gardens.

O. traillii Kirk in T.N.Z.I. 16, 1884, 372. Kirk based his sp. on specimens collected "in places near the sea, Stewart Island; also on Puysegur Point, South Island". He recognised that it was "in some respects intermediate between O. angustifolia Hook. f. on one side, and O. colensoi and O. lyallii on the other". Few specimens have been noted, but the origin O. angustifolia × colensoi var. grandis is clear. "A noble species", as Kirk says, worthy of cultivation.

O. suavis Cheesem. in T.N.Z.I. 24, 1892, 409. Cheeseman's original specimens were from "Mount Arthur Plateau, Nelson, alt. 4000'". Type: A, 9537, T. F. Cheeseman, Jan. 1886. He considered it, judging by description, close to Buchanan's excorticata, and allied in some respects to O. lacunosa, emphasizing the pale yellowish or fulvous tomentum. Several forms occur where O. arborescens and O. lacunosa meet and hybridize. For the "curiously diverse progeny" found on Mount Arthur, Simpson and Thomson (T.R.S.N.Z. 72, 1942, 33) suggest the origin O. capillaris × lacunosa. This was also the opinion of Mr. F. G. Gibbs, a close student of the area.

O. ilicifolia var. mollis Kirk Stud. Fl. 1899, 269. Kirk's specimens came from "Nelson, Dall; Westland and Broken River, Cockayne", and were varietally distinguished by their laxer tomentum, softer and smaller teeth. Cockayne (T.N.Z.I. 43, 1911, 173) argued that if O. ilicifolia and macrodonta were considered specifically distinct the var. mollis should equally be treated as a "valid species". Later (Ann. Bot., Lond. 48, 1934, 51) it was recognized that O. mollis was of hybrid origin, O. ilicifolia × lacunosa. The status of O. macrodonta remains uncertain. In the field, in a number of localities, it appears quite constant and distinct. On the other hand rather polymorphic groups occur, notably at Arthur Pass and in Fiordland, where O. arborescens meets with O. ilicifolia, some of the forms of which can hardly be distinguished from O. macrodonta. Seed from a specimen of O. macrodonta was found to give diverse progeny by Simpson and Thomson, but pollination was not controlled.

In general, there is good field evidence for the following hybrid groups: angustifolia × colensoi; angustifolia × semidentata; arborescens × avicenniaefolia and × capillaris, × ilicifolia, × lacunosa; avicenniaefolia × moschata and × odorata; chathamica × semidentata; crosby-smithiana × ilicifolia; ilicifolia × lacunosa.

Less certain are the groups: albida × furfuracea; avicenniaefolia × nummularifolia; ilicifolia × moschata : moschata × nummularifolia and its  var. cymbifolia. The virgata complex, on analysis, will probably be found to involve hybridism, and O. hectori may also be concerned.

Simpson and Thomson (T.R.S.N.Z. 72, 1942, 33) tentatively assign the origin O. avicenniaefolia × Celmisia du-reitzii to a single shrubby plant collected by J. Speden on the hillside above Arthur Pass township and cultivated in his garden. The lvs are 7-10 × 1·5-2 cm., thin and flaccid, somewhat viscid; the ray-florets are nearly 2 cm. × 3 mm.

FL. 2-5. FT. 4-6. Type locality:?

Placed us. under O. virgata or O. solandri, but of quite uncertain status, are two spp. of Colenso:

O. fasciculifolia (T.N.Z.I. 25, 1893, 330) was based on a small terminal part of a branch, forwarded by H. Hill from "open lands between Dannevirke and Weber . . . 1892". Colenso's description includes: "bark reddish-brown, striate, with more or less of orange-coloured dry waxy exudation . . . Leaves few, distant, fascicled in 3 and 4 . . . linear-oblong or sub-linear-spathulate, 11/2-2 (rarely 3) lines long, less than 1 line wide . . . dark-green glabrous above, greyish-white below with closely appressed hairs . . . Involucral scales many, imbricate in 6-7 rows, orange-coloured . . . Pappus scanty . . . Achene semi-terete, linear, 1 line long . . . glabrous."

O. consimilis (T.N.Z.I. 28, 1896, 596) was based on specimens collected by A. Olsen near "Norsewood . . . margins of woods and streamlets . . . 1895". Colenso's description includes: "Leaves numerous . . . fascicled, 5-7 together on the lower and 3 on the upper part of branchlets, opposite, but on flowering branchlets the terminal portion above the flowers has only single leaves opposite, erect, spreading, linear or sub-linear-spathulate, 2 lines long, 1/20in. wide, thickish, tip broadly rounded, base slightly tapering, sessile . . . Heads many, solitary, axillary, regularly opposite (in pairs) . . . Involucral scales many, imbricate in 4 rows, yellow, shining . . . Florets few (11) . . . Pappus nearly equal, white, shining . . . Achene linear, flattish, striate, glabrous, shining."