Art. XLIII.—A Comparison of the Indigenous Floras of the British Islands and New Zealand.
[Read before the Auckland Institute, 28th August, 1871.]
The traveller who may expect to find some of the more remarkable plants of the New Zealand Flora immediately on his arrival in the colony, will be sorely disappointed on his first examination of the vegetation. This is not simply because European plants have largely displaced indigenous kinds in the vicinity of the seats of settlement, nor even because those plants which most steadily resist the progress of the invaders are to some extent of the European type; it arises from the fact that, with a larger proportion of endemic plants in proportion to its area than any other country, there are but few kinds, more especially in the north, which give character to the landscape, and offer salient points for general observation. The first peculiar plants observed by the new-comer are the toe-toe and Phormium, to these in the north must be added the magnificent pohutukawa and the kowhara-whara; the remainder of the hundreds of plants peculiar to the colony must be sought in the damp forest gullies, or on the lofty mountain ranges.
But after the first feelings of surprise at the general resemblance of the vegetation in the vicinity of the ports to the European type have passed away, and the observations of our traveller are made over a wider range of country, he finds the resemblance after all to be merely superficial, for at every step in the forest he misses the bright forest flowers of the northern hemisphere: no wild hyacinth or wood-anemone; no primrose or cowslip; no dead-nettles, wound-worts, or hawk-weeds; no roses, brambles, or willows; but in their stead are numerous small trees, shrubs, and ferns, often with flowers of curious structure and strange leaves, from the slender karamu to the giant kauri and totara. And the same rule holds good if the open country is examined. There are none of the charming terrestrial orchids of Britain to be found on the grassy lands or fern-clad hills, and although much of the lacustrine and uliginal vegetation
exhibits a closer affinity,—in fact contains a larger proportion of plants common to both countries than the sections at which we have just glanced, still we miss the regal waterlilies, the flowering rush, the white and yellow bog-beans, the loose-strifes, arrow-head, and water-violet, which so often beautify the streams, lakes, and marshes of Britain. The forest vegetation of New Zealand comprises some of the grandest flowering plants known; the same must be unreservedly admitted of its alpine flora; but if we further except a few fine plants peculiar to the Auckland and Chatham Islands, there are scarcely any herbaceous plants remarkable for the beauty of their flowers. The social characters of the trees composing the sylvan flora of Britain contrast forcibly with those of the New Zealand forests. In the former, forests of oak, beech, Scotch fir, hornbeam, holly, etc., are, or rather were, not uncommon; but few of our trees exhibit this characteristic, more especially in the north. The kahikatea certainly forms large forests in the swamps Southwards, the beech on the hills, the tawa, and taraire, not unfrequently form large portions of the forest; the totara, the kauri, and a few other trees, occur in groves or patches; but, excepting the southern beeches, there is no tree which grows almost exclusively for miles, as was the case with the oak, Scotch fir, etc., etc. Our forests are highly varied, and not unfrequently exhibit a larger number of species of ligneous plants in a single district, than could perhaps be found in the greater part of Europe; but this almost tropical variety in itself detracts from the sense of grandeur which is inspired by continuous masses of any one kind of arboreal vegetation.
Ligneous plants form one-eighth part of the phænogamic Flora of New Zealand, but less than one forty-seventh part of the same section of the British Flora; and of this small proportion a limited number only can be called trees—the oak, ash, beech, hornbeam, birch, aspen, white and grey poplars, white and bedford willows, wych elm, holly, small-leaved lime, alder, maple, Scotch fir, and yew,—a number fully equalled by the New Zealand pines and beeches alone. Of British trees not a single species is marked by conspicuous flowers,* and only one by attractive fruit,—there is no representative of our pohutukawa and the various ratas (Metrosideros sp.), the rewa-rewa (Knightia excelsa), hinau (Elœocarpus dentatus), ixerba (I. brexioides), towai (Weinmannia silvicola), toro (Persoonia Toro), kohe-kohe (Dysoxylum spectabile), puriri (Vitex littoralis), ackama (A. rosœfolia), hohere (Hoheria Sinclairii), kowhai (Sophora tetraptera), lace-bark (Plagianthus Lyallii), and many others with their showy flowers—or, excepting the holly, of the tawa (Nesodaphne Tawa), taraire
[Footnote] * Possibly the male catkins of the white willow (Salix alba L.) may be considered sufficiently attractive to qualify the above statement: those of the bay willow (S. pentandra L.) are very handsome, but it can scarcely be called a tree.
(Nesodaphne Taraire), kahikatea (Podocarpus dacrydioides), miro (Podocarpus ferruginea), matai (Podocarpus spicata), titoki (Alectryon excelsum), and hedycarya (H. dentata), with their attractive fruit.
The striking characteristic arising from a rich variety of species, not seldom belonging to orders unrepresented in Britain, is intensified by the peculiar habits and mode of growth of many New Zealand forms. In the lower parts of the forest we find the pukatea (Atherosperma Novœ Zelandiœ), with the base of its trunk developed into wide-spreading buttresses, its white bark contrasting strangely with its bright green foliage: near it the maire-tawhake (Eugenia Maire), clothed from base to summit with white myrtle-like flowers and leaves, by the side of the tall shafts of the kahikatea, with its sparse foliage: on drier ground the tanekaha (Phyllocladus trichomanoides), and the striking toa-toa (Phyllocladus glauca) display their highly developed phyllodia; the grand columns of the kauri (Dammara australis) rise to the height of from sixty to eighty feet without a branch, and, from their bulk and symmetry, fairly claim the supremacy of the forest; the totara, remarkable amongst New Zealand pines for its peculiar bark, and oftentimes of huge girth, the much branched hinau with its flowers of creamy white, by the side perchance of an immense rimu (Dacrydium cupressinum), with its peculiar pendent branchlets, the kawaka (Libocedrus Doniana) or arbor-vitæ, recognised at a distance by its bark hanging in broad ribbon-like flakes and the young plants at its base, showing how apposite was its old trivial name “plumosum;” the puriri with its white slippery bark and glossy foliage; the huge, often mis-shaped northern rata (Metrosideros robusta), which, commencing life as an epiphyte on some forest giant, sent down aerial stems, and developed them into large trunks which have strangled the fostering tree, above the remains of which its branches wave, often a hundred feet from the ground, and laden with flowers of fiery crimson; the rawiri (Leptospermum ericoides) or tea-tree, with spray-like branches laden with myriads of white flowers, its loose bark waving in the wind; the miro and matai with their yew like foliage; the tawa, with leaves resembling some of the British willows, and its sister-tree, the taraire, perchance, with the dusky tints of its fine foliage appearing still browner from the close proximity of a glossy karaka (Corynocarpus lævigata). Here, fine panicles of white flowers break from the uneven bark of the kohe-kohe (Dysoxylum spectabile), with its walnut-like foliage, there a fine arborescent lily-wort (Cordyline sps.), the only plant that can be said to impart a special character to the New Zealand landscape, waves its palm-like leaves, every branch tipped by an immense panicle of fragrant flowers. Mingled with all the southern palm (Areca sapida) attains its extreme height of fifty feet, and exhibits at once both the grace and stateliness of its order, only surpassed in beauty by the noble arborescent ferns (Alseuosmia macrophylla) which abound in the moist gullies.
The same richness and variety of form and habit is manifested in the undergrowth. The British woods exhibit but few species: the hazel, buckthorn, dogwood, crab, hawthorn, service, black thorn, alder, and dwarf willows, form the chief portion of its underwood, which is margined with thickets of brambles and roses. New Zealand exhibits a vast series of shrubby plants and small trees, often producing showy flowers, and varying in kinds—from those found in the warm latitudes of Auckland to those of the cool moisture of Otago and Southland. Most conspicuous in the province of Auckland is the large leaved Alseuosmia, with its pendent fuchsia-like flowers varying from white to crimson, one of the most social plants in the colony. The white-flowered wharangi-piro (Olearia Cunninghamii), varying from a bush to a small tree, is the chief representative in the North Island of the numerous shrubby composites of the south. In rocky places the puka-puka (Brachyglottis repanda), recognised at a considerable distance by its hoary leaves, is abundant, and perchance growing amongst it the rhabdothamnus (R. Solandri), with its fairy-like bells of orange and scarlet. The hange-hange (Geniostoma ligustrifolia), the kawa-kawa (Piper excelsum), the ngaio (Myoporum lœtum), the pennantia (P. corymbosa), with its waxlike flowers, various coprosmas (C. grandifolia etc.), several species of senecio (S. glastifolius), with their white or yellow corymbs, shrubby veronicas (V. ligustrifolia, etc.), sometimes attaining the height of fifteen feet, and laden with snowy or lilac-coloured flowers; the lance-wood (Panax crassifolia), which at first is only a straight rod, perhaps, ten feet high, with linear, toothed, and mottled leaves eighteen inches long, growing downwards at an acute angle with the stem, then becoming slightly branched, it developes trifoliate leaves of a similar character, and ultimately as a small tree exhibiting simple linear-obovate, entire leaves, and unisexual umbels of green flowers. The whau-whau-paku, another araliad, with its broad handsome green foliage; the whau (Entelea arborescens), the ake-ake (Dodonœa viscosa), and numerous other kinds intermingled with a dense growth of a social asteliad (Astelia trinervia), and numerous “cuttinggrasses” (Gahnia setifolia, etc.), whose serrated edges speedily scarify the unprotected hands of the traveller.
But a still more striking point of contrast is afforded by the garniture of the trees. In British woods the solitary ivy is the only climbing plant which attains to the summits of the higher trees. A solitary clematis (C. vitalba) and the woodbine (Lonicera Periclymenum) complete the list of ligneous climbers. Rarely the polypody (Polypodium vulgare) may be seen amongst the forks of the branches, but as a rule, beyond a few mosses and lichens, the trees are bare of vegetable growth.
In the New Zealand forest the huge trees sustain entire assemblages of dissimilar plants. Asteliads (Astelia Solandri, etc.) growing on their limbs
present a peculiar feature in the landscape, and at a distance “resemble the nests of some gigantic bird;” their drooping scapes of waxy-looking flowers and crimson fruit being alike conspicuous and attractive. Trunks and branches are laden with epiphytic orchids, small pittosporads and other shrubs, ferns, pendent lycopods, and mosses, accompanied by large foliaceous lichens, to an extent which completely beggars description. Scandent ferns, which ascend to the tops of the highest trees present a feature totally unknown in the woods of Britain, and showy loranths adorn the branches with bright coloured flowers strangely out of harmony with the foliage of the supporting tree. The large white-flowered clematis (C. indivisa), with its massive foliage covers the outskirts of the forest during two months of the year, as with a sheet of purest snow; parsonsias exhibit their twisted and inosculated stems, ultimately producing jessamine-like flowers and pendent linear capsules. The well-known supple-jack (Rhipogonum scandens), with its flexible stems, often fills up the spaces between the trees, and renders progress both tedious and laborious, while the mange-mange (Lygodium articulatum), with its elegant foliage, its singular spore-cases and tough wiry stems, binds trees and undergrowth together in its net-like shrouds to such an extent that the traveller's path can only be cleared by the knife. Like its British allies, the tataramoa (Rubus australis), with its three or four strongly marked varieties, often forms impenetrable thickets, or ascending the lower shrubs by means of the hooked prickles with which its leaves are armed, ultimately reaches the tops of the loftiest trees, and with its cable-like stems partly coiled on the ground, partly suspended in mid-air, spreads its branches far and wide, and hangs its branched and elongated panicles of snowy diœcious flowers, absolutely without a rival in the genus to which it belongs. Adding the beauty of colour to that of form, scandent species of Metrosideros, a section almost peculiar to the colony, festoon the trees with brilliant flowers of white, red, magenta, and fiery crimson. How cold and sombre by the side of all this wealth of form, and warmth of colour, does the solitary ivy appear?
I have already pointed out the remarkable paucity of showy herbaceous flowers in the New Zealand forests as affording one of the most striking points of contrast between the two Floras. Their place is occupied by a large variety of ferns and allied plants of exquisite form, and often of delicate texture: now resembling miniature tree-ferns—now the shield ferns of Britain—of varied tints, from the tender green of adiantum (A. æthiopicum, etc.), the red and purple doodia (D. media), to the black Lomaria nigra—of all degrees of texture, from the filmy hymenophyllums, resembling delicate algæ, to the leathery todea (T. barbara)—now resembling humble mosses—now exhibiting the habit of the stately para (Marattia salicina).
In Britain Ferns and their allies form only one twenty-fifth of the Flora,
while in New Zealand they equal one-eighth, and the general difference in habit is as strongly marked. The peculiar effect produced by continuous carpets of the pellucid entire fronds of Trichomanes reniforme, or the finely cut Hymenophyllum demissum, in the cool open part of the forest, cannot be imagined by those conversant only with the Ferns of Britain. Tree-ferns, climbing ferns, and epiphytic kinds, are absent from the British Flora, and it exhibits none of those handsome and delicate filmy ferns, which are so luxuriantly developed in New Zealand; still, three species, Adiantum Capillus-Veneris, Athyrium Filix-fœmina, and Osmunda regalis, each in its respective habit, surpass all New Zealand forms in grace and beauty. Fifteen genera and thirteen species are common to both countries. The bracken of the British Islands is represented by a closely similar plant, having as wide a range of distribution, but no other Fern common to both countries has a distribution in New Zealand corresponding to its range in Britain; and the same remark applies to the representative forms, with the exception, perhaps, of the patotara (Botrychium ternatum). In conformity with the general law of plant distribution, the New Zealand Ferns, and their allies, decrease in number of species as they recede from the equator. In the Flora of the British Islands their distribution is decidedly polar, affording a marked contrast with the austral distribution of the great majority of its Phænogams.
Although many New Zealand Ferns occur at a great altitude, not more than three or four species are so purely montane in their habit as the British Woodsias, or Cystopteris montana. A few purely tropical species are found luxuriating in the increased temperature afforded by the close proximity of hot springs.
Equisetum, which is a prominent genus in many parts of the British Islands, has no representative in New Zealand.
The open land in Britain is usually covered with a mixed and compact growth of grasses and small forage plants, or with furze, heather, or bracken interspersed with thickets of brambles, sweet-briars, dog-roses, dwarf-willows, and one or two other shrubs which afford cover for a large number of herbaceous plants and a few ferns. In New Zealand, the southern bracken (Pteris esculenta), the manuka (Leptospermum scoparium), and, restricted to the north, the tauhinu (Pomaderris ericifolia), are the chief ericetal plants of social habit. These are dotted with bushes of makaka (Carmichœlia australis), with its leafless branches, the representative of the yellow broom of Europe, tupakihi (Coriaria ruscifolia), karamu (Coprosma lucida), koromiko (Veronica salicifolia, etc.), pimelias (P. prostrata, etc.), epacrids, and other shrubby heath-worts, with a large number of small-growing or stunted shrubs. In favourable spots a few small terrestial orchids are found of types quite unknown to the British Flora. In moist places various species of Cladium
and Schœnus abound, differing widely in appearance from the solitary British representatives of these genera. Lomaria procera and, in the south, L. vulcanica, often cover large areas. The peculiar appearance of Gleichenia circinata, the erect Lycopodium densum, and the semi-scandent habit of L. volubile, cannot be compared with any British plants in regard to habit of growth. A few willow herbs and other herbaceous plants, especially several species of Haloragis, are of frequent occurrence, but insignificant appearance. Many grasses are sparingly scattered amongst the shrubs and fern, but they rarely assume a social character; even on the plains of the South Island they seldom form a compact sward, unless mixed with introduced species.
Phormium tenaæ everywhere affords a striking feature, especially when in flower, and the huge tussocks and lofty panicles of the toe-toe (Arundo conspicua) at once attract attention; the cutting toe-toe (Cyperus ustulatus) is abundant on moist ground, and is remarkable for its singularly harsh and rigid habit.
It must be admitted that the manuka, although copiously sprinkled with snowy blossoms, offers a poor substitute for the furze and social heaths of Britain, with their attractive flowers. The herbaceous composites of Britain, with the exception of two or three forms, are not represented; its showy water-crowfoots are unknown; its charming milk-wort; its crucifers and cloveworts. The absence of its roses, brambles, and hawthorn, is at once noticed, even by the most careless observer. No trefoil, clovers, vetches, or wild peas, are found here. The showy bell-flowers are poorly represented by two or three species of Wahlenbergia. Its lowland forget-me-nots, its mullein and toad-flax, louse-wort and yellow-rattle, primrose and loose-strifes, have no substitutes. One or two speedwells closely resemble English forms, but they are rare and local; as are the lowland eyebrights. The dead-nettles, bugles, germanders, and other labiates, are represented only by a single species belonging to the order in the North, and by two only in the South Island. Spongeworts, so numerous in Britain, are represented by a single littoral species. With one exception, the charming terrestial orchids of Britain are represented by widely different forms, which evince a closer affinity with the Tasmanian Flora than is shown by any other group of New Zealand plants. The absence of the showy flowered lacustrine plants of Britain has already been pointed out, I will only add that, with one exception, the New Zealand water-milfoils are more or less subaquatic. I have only met with one species that is constantly submerged. Myriophyllum robustum especially, which is allied to the British M. verticillatum, is never submerged, but may be seen in the country between the Thames and Waikato, growing in immense abundance, three to four feet in height, and resembling a miniature pine forest.
The littoral section of the Flora differs from that of Britain in the presence of several peculiar plants. In the north, the pohutukawa (Metrosideros tomentosa), sixty feet high, with gnarled, distorted branches, laden from base to summit with deep crimson flowers, is often found with its trunk washed by the sea; the mangrove (Avicennia officinalis) covers mud-flats exposed at low-water, and often attains thirty feet in height; its creeping roots and innumerable suckers present a singular feature. Other trees prefer a littoral habitat, as the pau (Sapota costata), which has a similarly restricted range to the above, and others. The ngaio is abundant all round the coast, and is also found inland. A glossy leaved karamu (Coprosma Baueriana), and one or two shrubby veronicas and composites, also affect a littoral habitat. The arenarian plants are singularly uniform on all the coasts. The pingao (Desmochœnus spiralis) with its interrupted spike, Spinifex hirsutus, and Festuca littoralis, are confined to loose or shifting sand, and to some extent take the place of the marrem and sand-sedge of Britain, but present a singular appearance. Two other plants of opposite habit give à peculiar character to sandhills and beaches—Coprosma acerosa, with its tortuous wiry brown stems and acicular leaves, and the erect Pimelea arenaria covered with white silky hairs. Convolvolus Soldanella, and several other littoral plants, are common to both countries. The New Zealand spinach (Tetragonia expansa) and a large marshsamphire (Salicornia indica) are abundant in salt marshes. Except a large asteliad (Astelia Banksii), common on the cliffs, there are but few other forms of special importance. Zoysia pungens, a littoral grass, is one of the few New Zealand kinds which form a compact turf.
So little precise knowledge has at present been collected with regard to the altitudinal range of New Zealand plants, especially of their lower limits, that I am only able to point out some of the more remarkable alpine forms, without reference to climatal conditions. Dr. Hector has stated the general features of their distribution in an essay appended to the first volume of the Transactions of the New Zealand Institute. I may, however, remark that no mountain in Britain exceeds the altitude of 4,330 feet, the mean temperature of which is computed by Watson at 36.6 deg. Fahr. Not more than twenty-five species are found in Britain at a greater altitude than 4,000 feet. It is probable that one-eighth, or possibly one-seventh, of the New Zealand Phænogams and Ferns occur between 4,000 and 9,000 feet of altitude, although the number of species restricted to these limits would be much smaller. The comparative paucity of ferns at these altitudes contrasts forcibly with their abundance at lower ranges.
Conspicuous amongst the sub-alpine plants are the magnificent Ranunculi, R. Lyallii, and R. Traversii—the “water lilies” of the shepherds. Mr. Potts informs me the peltate leaves of the former are sometimes two feet in diameter;
their erect stems and waxy-white flowers, combined with their peculiar leaves, render them “the grandest species of the genus.” R. Godleyanus and R. insignis are also noble species. R. Sinclairii and R. sericophyllus are interesting forms of smaller growth. The remarkable genus Aciphylla comprises the “spear-grass” and “bayonet-grass” of the colonists, so-called from their rigid pungent leaves, which occasionally inflict uncomfortable wounds on incautious travellers. Many species of Ligusticum are found at great altitudes. Celmisia is a peculiarly montane genus, comprising twenty-five species, only two of which are found north of the Auckland Isthmus. It is characterized by linear radical leaves surrounding numerous one-flowered scapes, the leaves varying from half an inch in length to nearly two feet; acicular, or broad; membranous, or clothed with densely appressed tomentum; the flowers are almost sessile, or on long scapes, and in some species fully three inches in diameter. Strange looking Ozothamni abound, with imbricated appressed leaves, clothed with cottony tomentum, or shining. Perhaps the most singular forms are the species ofRaoulia and Gnaphalium, known to the shepherds as “vegetable sheep;” the stems are so closely compacted that it is impossible to thrust the fingers between them, and the imbricated, closely appressed leaves are clothed with a dense coating of velvety hairs. In the closely allied genus Haastia the plants form rounded cushions, several feet in diameter, the leaves being clothed with cottony wool. Several pastoral epacrids represent to some extent the crow-berry of the British mountains in habit. The mountain gentians, with their handsome yellow or purplish flowers, are amongst the most attractive of the genus. Myosotis comprises several species of similar habit to the British M. alpestris, with others, having terminal, solitary flowers, and hoary leaves. Numerous shrubby veronicas and a few herbaceous forms occur as sub-alpines; amongst the former is a group of singular forms, usually with closely appressed or imbricated leaves, but occasionally developing others of various forms, which are spreading and pinnatifid. Showy species of Euphrasia are frequent, and moss-like patches of the genera Pygmea and Forstera are not uncommon.
The alpine section of the British Flora exhibits no such striking plants as the above, either with regard to form or beauty; in many parts a compacted growth of Salix herbacea, Carex rigida, and Lycopodium alpinum is found on the highest peaks. Silene acaulis, Gnaphalum supinum, Saxifraga stellaris, Viola palustris, a few hawkweeds, alpine Cerastia, willow herbs, Alchemilla alpina, Empetrum nigrum, four or five grasses and rushes, Saxifraga oppositifolia, S. nivalis, Sedum Rhodiola, Lomaria spicant, Lycopodium Selago, Polygonum viviparum, Cochlearia officinalis, Thalictrum alpinum, and Oxyria reniformis, form the bulk of the sparse vegetation at and above 4,000 feet. About one-fifth of the British phænogamic plants and ferns occur between 2,000 feet and 4,330 feet; many of these, however, descend much lower.
The rarity of flowers with blue corollas in the alpine plants of New Zealand, and in its Flora generally, is noteworthy. There is no plant in any way resembling the charming Gentiana verna, so abundant in certain localities in the west of Ireland and in the north of England, or Veronica alpina V. saxatilis, and other species. The British veronicas, however, are without exception herbaceous,* and are closely represented by several New Zealand species, one of which is identical.
In closing this very imperfect sketch, I will simply add that although more than one hundred British species have become naturalized in New Zealand, only one (Cotula coronopifolia, L.) of our indigenous plants has become in any way established in Britain, and even that may prove to have been introduced from Australia or from Southern Europe.
[Footnote] * Veronica fruticulosa, L., has no claim to be considered a British plant.