New Zealand Plants and their Story
Chapter VIII. — The Plants of the Outlying Islands
The Plants of the Outlying Islands.
A goblin forest—The ancient forest of Antarctica—A seashore cushion-plant—Finest floral display outside the tropics—Giant tussocks—Young albatroses —Macquarie Island—The Snares—Disappointment Island—Beetles, spiders, and amphipods of the Bounties—Peculiar trees of the Chathams—A lovely shrub—The tree-groundsel—The great forget-me-not—The Kermadec Islands—Tropical plants on the Kermadecs.
The Subantarctic Vegetation.
Lands of mist and sleet and hail, of fierce squalls born in the icy south; cruel, rock-bound coasts, scenes of brave men's death, or of fierce struggles with the angry sea; lands of brown hills, enclosed by thick woods, weird and grotesque—in very truth goblin forests, patrolled and sentinelled by uncouth monsters of the deep: such impression may our far-off subantarctic islands give at first.
A closer view, and scenes more pleasing greet the traveller. Despite the ever-present gales, fields of magnificent flowers clothe the hills in summer-time. Within the forest, beneath the thick entanglement of gnarled and twisted branches of the trees, multitudes of ferns spread out their feathery fronds into the dim light. The knotted trunks, the fallen trees, the uneven ground, all are thickly covered with a mantle most delicate of translucent filmy ferns. Mounds of exquisite liverworts of many species adorn both forest-floor and boles of trees. Thickets of shrubs abound. All is one close mass of vegetation, save where long, bare paths of dark peat lead from the dim recesses of the forest, along which a startled sea-lion may glide, fearful of the intruder, or one at bay greet him with angry roar and open jaws.
It is in the Auckland Islands alone of these lonely lands that any true forests are to be found. In Campbell Island trees are altogether absent; densely growing shrubs clothe the lower slopes and fill the gullies. In Antipodes a few lines or patches of shrubs show as dark spots amongst the all-prevailing tussock, while on Macquarie Island woody plants are quite wanting.page 115
The forest of the Auckland Islands consists for the most part of the southern rata (Metrosideros lucida).The other associated trees and shrubs are the haumakoroa (Nothopanax simplex), the evilsmelling karamu (Coprosma foetidissima), the inaka (Dracophyllum longifolium), Coprosma ciliata, C. parviflora, Suttonia divaricata, and, where the forest changes into scrub, Cassinia Vauvilliersii. The extraordinary manner of growth of this society; the close, even foliage of its roof; the twisted, far-reaching branches, semi-prostrate and arching trunks, and consequent lowness of the trees, are plainly the expressions of the tempestuous climate—rigorous enough in many ways, but never really cold (fig. 54). Within the shelter of the forest quite other conditions exist, so here flourish those plants that love an atmosphere saturated with moisture. As for the affinities of the forest, they are subtropical and not subantarctic. Here, of all places, where a beech (Nothofagus) forest might be expected, it is absent.
In some few parts of these subantarctic islands—namely, on Ewing Island of the Auckland Group, to a limited extent on the north of Auckland Island itself, and especially on the Snares—are small woods of another character. These are composed of the truly magnificent daisy-tree (Olearia Lyallii), found only in these islands, but closely related to O. Colensoi of Stewart Island, the New Zealand Alps, and the North Island mountains. O. Lyallii has great leathery leaves, which are green on the upper surface but pure white beneath, thus affording a delightful contrast when they are stirred by the wind. Probably this society is a modified remnant of the ancient forest of that latitude and farther south, which during the great expansion southwards of New Zealand in later Tertiary times was driven into its present narrow limits by the invading and more vigorous rata forest of the north. The meadows of herbaceous plants, too, are possibly to be similarly accounted for—that is to say, they are a remnant of the subantarctic meadows of long ago.
On the Snares, mixed with O. Lyallii, is the rare and beautiful small tree, one of the shrubby groundsels (Senecio Stewartiae). Strange to say, though this plant also occurs farther to the north, it has not been found on Stewart Island proper, but only on some of the small islands in its vicinity.
Some of the seashore plants are very wonderful. Here, almost to high-water mark, comes a splendid tussock-grass, Poa foliosa, with broad green leaves. On the rocks, almost where the sea washes, page 117are large green cushions of Coldbanthus muscoides, hard as those of the vegetable-sheep; and near by will be frequently seen the shining green rosettes of a species of plantain (Plantago carnosa?). Close by, where the kelp heaves on the restless waters, swims, quite fearless of man, as it has done for ages, the little flightless duck. From the cliffs droop green draperies of a most strange pale-green, soft-leaved grass (Poa ramosissima), while their summits are crowned with the sweet-scented Veronica elliptica. On the flat rocks beneath stands, sentinel-like, the Auckland Island shag, conspicuous with its glistening black back, spotless white breast, and flesh-coloured feet; and accompanying it is the pretty little mackerel-gull, with dove-coloured back, white head and breast, and brilliant red legs and beak.
The herbaceous plants are the special glory of the islands. Sir Joseph Hooker has declared that outside the tropics no such floral display is to be seen in any area of the same size. The monarch of all is a majestic plant of the daisy family (Pleurophyllum speciosum), the genus being purely subantarctic, though related to the asters of gardens. The leaves are of great size, and all are corrugated. In colour and general appearance they somewhat resemble pale-green velvet or plush, and they are so arranged at times as to look like shallow goblets. These are striking enough; but when the beautiful purple flower-heads are raised high above the leaves, dozens at a time, side by side, the spectacle is magnificent. There are perhaps three other species of the same family. One (P. Hookeri), with silvery leaves just tinged with green, dotting the upland meadows as far as the eye can reach, is a charming-enough sight. But how intensified is the beauty when there are present in large numbers, and also in full bloom, a fine yellow buttercup (Ranunculus pinguis); gentians pink, violet, and crimson (Gentiana cerina); the blue Veronica Benthami; the gorgeous orange-coloured liliaceous plant Bulbinella Rossii; the prince of forget-me-nots, its blossoms ultramarine (Myosotis capitata); and mats of the stiff rosettes of Celmisia vernicosa, the leaves like polished greenstone, and bearing many fine flower-heads with purple centres and white rays. Other magnificent plants are two of the carrot family, with great masses of close-growing purple blossom (Aciphylla latifolia and A. antipoda), the former with leaves reaching to the middle of one's thigh; and a close ally Stilbocarpa polaris, whose massive creeping stem afforded a valuable food fox the unfortunate castaways of the "Dundonald."page 118
The tussocks tank with the forest and the meadow as an astonishing feature of these islands. Their habit is that of the niggerhead described in Chapter VII. On Antipodes Island, and in some parts of the Auckland Group, they are in many places quite 4 ft. tall, and grow so closely that to make any progress at all one is compelled to walk upon their tops (see frontispiece). On Antipodes Island these tussocks take the place of arborescent growth, and it is curious to see the little parakeet peculiar to the island perched and swaying on the drooping grass-leaves. Where the tussocks are lower, the albatros rears its young, bringing daily the supply of food. Here, too, the baby birds, clad in downy robes of snowy whiteness, each seated on its cheese-shaped nest, brave for months the piercing antarctic blasts, until their time shall come to seek the white-topped waves and follow in the wake of the great ships.
Although Macquarie Island belongs to Tasmania, biology derides the claims of nations, and emphatically declares it to be three-fourths New Zealand and the rest Fuegian. This latter claim is specially emphasized by the immense cushions of Azorella Sclago, the Fuegian rival of our vegetable-sheep.
The Snares, the nearest to Stewart Island of the subantarctic group, do not contain nearly so many peculiar plants, though they have an Aciphylla and a species of Stilbocarpa not found elsewhere. They form, as might be expected, a connecting-link with Stewart Island.
Disappointment Island, in the Auckland Group, the scene of the terrible "Dundonald" wreck, is the home of countless mollymawks. Cast your eye over the dreary landscape, and you will see brown meadow dotted with white birds, and here and there patches of vivid green. This last arises from the presence of the antarctic burr (Acaena Sanguisorbae, var. antarctica).As the tussock, with its accompanying plants, is slowly but surely destroyed by the many generations of birds, this burr takes complete possession of the bare ground, thanks to its colonising-power, for the barbed fruits adhere to the feathers of the young birds, and so are spread broadcast. The burr is really quite a rare plant in the tussock meadow, and so we have a remarkable example of a plant originally of little importance becoming, in a virgin vegetation, virtually a weed. But tussock will again predominate, and gradual alternate destruction and rejuvenation of the vegetation will always be in progress—a natural rotation of crops indeed, thanks to the presence of mollymawks.page 119
Fig. 55.— Penguins destroying Tussock Meadow. Low forest of Olearia Lyallii in the background, and tussocks. The Snares.
Phil. Inst. of Canterbury.] [Photo, L. Cockyane.
There yet remain for mention the Bounty Islands. So far as plant-life goes, their description is easy. A few seaweeds are on the rocks, while, where the sea cannot reach, the glitter of their monumental granite is dimmed only here and there by the green stain of an alga, their sole land plant. During part of the year these desolate rocks are a scene of busy life. Penguins in countless hosts stand in close array from base to summit of the islands (fig. 55).* Furseals bask on the warm rock, which everywhere by them and by the feet of former penguins is polished smooth as glass. Here, too, the mollymawk makes its curious nest of penguin-quills and guano, and beneath the stones in this latter is teeming life of beetles, amphipods, and spiders.
* The photo represents a penguin colony on the Snares, not on the Bounties; but the general effect is similar.
The Chatham Islands and their Plants.
At a distance of about five hundred miles from the coast of New Zealand, and almost due east from Lyttelton, lie the Chathams. This group has a flora quite as interesting as its subantarctic sisters, but, owing in part perhaps to the milder climate and more northerly situation, of a different character. Subalpine meadows, fields of herbaceous plants, rata forests—all these are absent. A forest of another character flourishes, distinct, too, from any other of New Zealand. The trees have a very familiar appearance; they look old friends, but are somewhat different. Surely this is the well-known koromiko; but never did one see that as a tree 50 ft. in height. Here is the lancewood, but where is the well-known juvenile form? Here, too, is the korokia of the north, yet its leaves seem larger and its yellow fruits bigger. The truth is that long isolation from the mainland has, in some way or another, led to slight differences between many Chatham Island and New Zealand plants. They have certainly come from a parent stock—perhaps one or the other is the actual parent; but now, although closely related, they are for the most part distinct species. The lancewood is neither Pseudopanax crassifolium nor P. ferox —it is P. chathamica; the koromiko is not Veronica salicifolia —it is V. gigantea; while the korokia is named Corokia macrocarpa, and in its larger fruit and broader leaves is distinct from C. buddleoides of the North Island.page 121
There is no shrubby undergrowth in the forest, but tree-ferns and ferns of all kinds are very abundant. The only lianes are the supple-jack, the climbing-convolvulus (Calystegia tuguriorum), and Muehlenbeckia australis. Many most characteristic New Zealand forest-trees page 122are quite absent—e.g., all the taxads, the beeches, the palm-lilies, and the pittosporums.
In the neighbourhood of these olearia bogs the margin of the forest often consists entirely of the rautini (Senecio Huntii), a mag-page 123nificent tree-groundsel, which produces immense bunches of yellow flower-heads, and has aromatic pale-green leaves in semi-rosettes at the ends of its stiff, bare, brittle twigs. For many hundreds of yards at a time this belt extends, forming, when covered with its golden blossoms, a gorgeous mass of colour.
The most famous of all the Chatham Island plants is the giant forget-me-not (Myosotidium nobile) (fig. 1), frequently called by the absurd name of Chatham Island lily, or, what is worse, Macquarie cabbage! This wonderful plant, found nowhere else in the world, is now almost extinct. Formerly it extended almost round the main island, forming a broad belt on the sea-shore, just above where the dry page 124seaweed marks the high-tide limit. The massive, shining, broad, green leaf-blades, a foot or more in length, raised high from the ground on stout leaf-stalks, and the numerous blue flowers, each half an inch or so in diameter, render this plant a most conspicuous object. The seeds germinate rapidly if fresh, and seedlings are raised with the greatest ease. The writer has long thought this noble plant might easily be naturalised on our northern sea-shores—for instance, on the Little Barrier and on Kapiti. Surely some effort could be made to fence a piece of the Chatham Island shore from sheep and pigs, so that this rare and interesting plant could once more reassert itself in its natural station.
Other interesting Chatham Island plants are the mutton-bird plant (Cotula Featherstonii), which grows only near the holes of the petrels; the shrubby speedwells, Veronica Dieftenbachii, V. Barkeri, and V. chathamica, this latter a charming little plant, of which there are many distinct forms, which creeps over rocks close to the sea; the great sowthistle (Sonchus grandifolius), which grows on sand-covered ledges of rock near the sea, or at times on the dunes; the bog-grass, Poa chathamica, an important fodder plant; the Chatham Island cranesbill (Geranium Traversii), of which there are white and pink varieties; the swamp-matipo, Suttonia Coxii, with its pretty mauve fruits; the gentian, Gentiana chathamica; and two spear-grasses, Aciphylla Dieffenbachii and A. Traversii.
Settlement has in many places quite changed the face of the country. In some places are fine grass paddocks, in others the bracken-fern and the piripiri (Acaena novae-zealandiae) have become weeds. Phormium tenax was originally very common, but is now a thing of the past in most cases. The Chatham Island variety differs from any in New Zealand proper in its broad and rather drooping leaves and their weak fibre.
From the subantarctic islands to the subtropical Kermadecs is a long step, and, yet the dominant tree in the latter is also a Metrosideros (M. villosa), a relation, however, of the pohutukawa and not of the southern rata. But with this the similarity between the two regions ends, except that both are of volcanic origin; and there is no more outward resemblance between the plant-forms than there is between the climates.
As seen from the sea, there is nothing in the appearance of the plant-covering of the Kermadecs to recall the tropics. No feathery cocoanut-palms fringe the shore. On the contrary, the rather dull hue of the New Zealand foliage, as seen from a distance, is everywhere manifest.
Sunday Island, the largest of the group, is forest-clad, while Macauley Island is almost entirely without arborescent growth. The whole group is of volcanic origin, as stated above, and the small Curtis Island is still in the solfatara state.
A certain number of tropical plants have reached the Kermadecs, but nothing like what might be expected. Amongst these are Ipomaea pes-caprae (which forms the well-known plant society on so many tropical shores), Canavalia obtusifolia (a climbing leguminous plant), Ageratum conyxioides (which bears the name of cherry-pie, or wild heliotrope), Aleurites moluccana* (the candlenut of the Polynesian Islands), and also some grasses and one or two ferns.
Certain plants are peculiar to the group. Amongst these are two coprosmas, C. petiolata and C. acutifolia, the former closely related to C. chathamica, of Chatham Island; Suttonia kermadecensis, related to a Norfolk Island plant; Homalanthus polyandrus, a tree of the spurge family; and two fine tree-ferns, Cyathea Milnei and one discovered by Oliver and named by him C. kermadecensis.
But the rank and file of the plants are such as would be met with in the North Island—for example, the karaka, ngaio, wharangi (Melicope ternata), mahoe, tutu, ivy-tree (Nothopanax arboreum), &c. In fact, about four-fifths of the flora † consists of ordinary New Zealand plants.
* According to Oliver this is not indigenous.
† According to Oliver there are 114 species, which belong to 88 genera and 42 families.