The rocks of the alpine summits weathering away, and the rain not being sufficient to bear all the débris into the valleys, an enormous quantity of angular stones collects on the mountain-sides in many places, which may form steep slopes for thousands of feet. As the traveller wearily ascends these "shingle-slips," as they are called, the stones constantly slip beneath his tread, and slide down the slope. Numerous large grasshoppers, grey as the shingle, leap from beneath his feet, an occasional black butterfly flits through the air or rests upon a rock, while overhead may fly screaming that famous bird the kea. All is a scene of utter desolation: it is, in truth, an alpine desert. Yet many of the meadows must have begun their career as shingle-slips, and all transitions may be noted from the one to the other.
To the shingle-slip proper belongs a most peculiar series of plants. They have several characteristics in common. All have long roots and are low-growing. Many are succulent. Most are of a colour similar to the shingle. Some have leaves of rather an indiarubber like texture, and one, at any rate, is covered with an exceedingly woolly mass of hairs. These shingle-slips become burning hot in the sunshine, and yet in the evening of the same day may be icy cold. At some distance below the surface the stones are wet. Here are a few of the plants to be found in such situations: A. stiff-leaved grass (Poa sclerophylla); a buttercup (Ranunculus Haastii); a plant of the carrot family (Aciphyila carnosula); a daisy, jet black, and with stamens like golden pin-heads (Cotula atrata); one of the pink family (Stellaria Roughii); the curious and sweet-scented penwiper plant (Notothlaspi rosulatum) (fig. 46); and a fleshy - leaved lobelia (L. Roughii).A piripiri, too (Acaena glabra), is almost confined to this peculiar station. These plants do not grow closely side by side. They are few and far between, and without close observation the slopes look quite bare. Occasionally a trailing - veronica (V. epacridea) sprawls over the stones, and is frequently accompanied by a smaller species of the whipcord form, V. tetrasticha.
On the shingle-slips the wonderful vegetable-sheep are encountered. These grow not on the shingle, but on the rocks which the stones have nearly buried. Large examples form great hummocks, 6 ft. long by 3 ft. across, or even more. Really they are shrubs of the daisy family, and are provided with a thick, stout, woody main stem and strong roots, which pass far into the rock-crevices. page 98
Above, the stems branch again, and again, and towards their extremities are covered with small woolly leaves, packed as tightly as possible. Finally, stems, leaves, and all are pressed into a dense, hard, convex mass, making an excellent and appropriate seat for a wearied botanist (figs. 47
). Within the plant is a peat made of rotting leaves and branches, which holds water like a sponge, and into which the final branchlets send roots. Thus the plant lives
Fig. 46.—The Penwiper Plant (Notothlaspi rosulatum), growing on shingle-slip of a river-terrace. Castle Hill, Canterbury.
[Photo, L. Cockayne.
in great measure on its own decay, and the woody main root serves chiefly as an anchor. The vegetable-sheep are not inaptly named, for at a distance a shepherd might be misled. The two principal "sheep" are Haastia pulvinaris
and Raoulia eximia;
but there are other smaller ones—e.g.
, R. bryoides
and R. Goyeni
, this latter of the Stewart Island
Closely related, to the shingle-slips, so far as the conditions for plant-life go, are the scoria-slopes of the volcanoes of the central plateau of the North Island. But on these the plant-life is still more scanty. Except Claytonia australasica
, which, strange to say, is also a plant found in shallow running water, all the South Island shingle-slip plants are wanting. In their place is a true alpine gem, Veronica spathulata.
which possesses a root of enormous length, small succulent leaves close to the cinders, and in summer is altogether covered with multitudes of snow-white flowers, which quite hide the foliage (fig. 49
Fig. 47.—The Vegetable-sheep (Raoulia eximia), a rather small example, growing on rock rising from shingle-slip. Mount Torlesse, Canterbury
[Photo, L. Cockayne.
Another veronica forms large mats, chiefly in the shelter of rocks (V. HooKeriana
).It also is very pretty with its lilac flowers raised on moderate-sized stalks above the foliage. But the plant par excellence
of the scoria deserts of the region in question—and they are deserts in all truth—is a species of Dracophyllum
), with stiff recurved leaves at the end of prostrate rigid naked branches. The shrub as a whole is of a reddish colour, and gives a characteristic stamp to the dreary landscape.
Finally, the New Zealand, edelweiss must be mentioned, of which there are two species, Helichrysum grandiceps and H. Leontopodium. Both are exquisite, and surpass their celebrated. Swiss namesake, Leontopodium alpinum. Perhaps H. Leontopodium (fig. 50), when in-full bloom, as it may be seen in late January on the Tararua and Ruahine Mountains, is the most beautiful plant in New Zealand. A near relation, but much more common, is H. bellidioides (fig. 51).
Fig. 48.—Bringing Vegetable-sheep from 5,000 ft. on Mount Torlesse for the Christchurch Exhibition of 1906-7.
[Photo, L. Cockayne.