Vintage year in Canterbury for mountain flowers

Press, 18 February 1989, Page 26

Vintage year in Canterbury for mountain flowers

Country Diary

Derrick Rooney

I’ve had the good fortune to get out into the mountains — via ski-field roads — several times in the last week or two, and would like to make it known to anyone dithering over what to do this week-end that floristically speaking this is a vintage year in Canterbury’s mountains, especially for the cream of our autumn mountain flowers, the gentians. In the Hutt, Torlesse, and ’ Craigieburn Ranges especially, I ' don’t believe there has been as good a gentian year for a long time. And since you can see . these plants at their finest in - several places without walking ‘ more than a few hundred metres from a main road, there isn’t any excuse that a keen person of any age could offer for missing them. I think the two most impres- ’> sive mountain plants this year are the giant Spaniard Aciphylla colensoi var. maxima and the snow gentian Gentiana corymbifera — arguably the most beautiful of our late-season mountain flowers. All the other gentians appear to be having an exceptional flowering year also. V New Zealand’s gentians, beautiful though they may be, are in a manner of speaking misfits. Unlike the gentians of the Northern Hemisphere, which are known for their . clear blue flowers. New Zealand’s mainland gentians nearly all have white flowers* One or two are pink or veined with pink. Furthermore, whereas the • Northern gentians are fairly <•' » n giiy grown in gardens, those of New Zealand’s mountains have a " powerful aversion to domesticattion.wThey are wild plants i* the striffist sense* ■ ■

All of this, plus certain botanical features which are at odds with Northern gentians, have led some taxonomists to suggest that New Zealand’s gentians might be better placed in a new genus. This shaky botanical status in no way detracts from our enjoyment of these elegant plants; The biggest and boldest among them is the snow gentian — essentially a plant of alpine meadows, where it grows among clumps of tall snowgfass. The branched heads of pure white flowers are on stout stems that may rise 50cm, but are usually shorter. , ,<?

You don’t have to tramp for miles to see the snow gentian; at Porters Pass and at the top of Arthur’s Pass it grows close to the road. From this subalpine zone its range exends upward about 500 m to the high fellfields and snow hollows, where it is joined by smaller but equally beautiful species, of which the most common in Canterbury is the mountain gentian, G. bellidifolia. A < The latter is part .of a complex

which is not well defined and may include one or several species. The biology and distribution of New Zealand’s gentians are not well understood — nor, while the shortage of funds for “pure” science continues, will they be. The snow gentian is what botanists call “monocarpic” — it grows for two or several seasons until it flowers, and after flowering once it ripens seed and dies. The mountain gentian also seems to be usually monocarpic but may have perennial forms. Noone seems to be quite sure. One thing is certain, however — it is futile to dig up plants of any of our wild gentians from the mountains and carry them home to a suburban garden. Don’t do it. If you want to try to grow them, collect a pinch to seed instead. .1 wouldn’t like anyone to get the impression that the gentians are the only late wildflowers to look for in the ranges. They certainly are not. In the Craigieburns and on Mt Hutt last week, there were huge patches of a pink parahebe in full flower at the streamsides; swaths of the water-loving, blush pink Epilobium macropus, with some of its stems trailing under water; and masses of white edelweiss on the drier ground. Scattered in rocky gullies were snow marguerites, white helichrysums, button daisies, and numerous species of the mountain daisy, Celmisia.

On the south side of Mt Cheeseman, which we approached from the Ryton Valley, our tramping trio found II species of Celmisia, plus several

hybrids. Some were showing seedheads, some were still flowering, and some had both seeds and flowers.

Except underneath permanent snow or ice there are plants of real character everywhere in our mountains; even above the permanent snowline a few species live precariously in rock cracks and crannies where snow cannot lie.

Plants live even in the great screes, the prominent features of Canterbury’s . mountainscape: great sweeps of broken shingle, slowly moving down the eroding mountainsides, often extending for hundreds of metres. From a distance, and, at a casual look, from close to, these scree slopes appear barren. But they are home to about 20 highly, adapted species which grow only in this

hostile habitat, among the moving shingle. Two of the handsomest bear the name of the great New Zealand naturalist, Julius von Haast, founder of the Canterbury Museum — Ranunculus haastii and Hebe haastii.

Among the others are the remarkable black-flowered button daisy, Leptinella atrata; a curious member , of the chickweed family, Stellaria roughii; and a fleshy leaved lobelia, L. roughii. All of these plants survive because they have stout, fleshy roots or rhizomes strongly anchored in the sticky grit and rock flour underneath the coarse rubble, and to which flowers and foliage are tenuously attached. Icy-cold water, trickling down beneath the rubble, continuously

supplies these rhizomes with moisture. If the tops are swept away the roots live to sprout again another day.

Screes are the habitat also of the penwiper plant, Notothlaspi rosulatim, a singular cress known only from New Zealand. In its first year the penwiper has a rosette of tightly overlapping leaves, and in the second it carries close heads of sweetly scented flowers. When not in flower, the penwiper is nearimpossible to spot: like many of its companion plants, it has foliage almost exactly the colour of the greywacke scree. Unlike them, it is monocarpic, dying after flowering and seeding, usually in its second year. The other scree plants are perennial.

Most of them have succulent (in the botanical sense) foliage. Others are covered with dense masses of white, woolly hairs for protection against the severe climate; if the hairs are gently, and carefully, removed, quite normal-looking leaves are revealed. Where the screes are finer and more stable the number and diversity of species increases. Among these, in the Craigieburns, one of my tramping mates found an odd-lookirig scabweed which I was able to identify as an undescribed species that goes by the undignified name of Raoulia species “Dirty” — so tagged because while its young growing tips are bright silver-grey, its older foliage is shabby greyish-black. I had seen it only once before — in the Wairau Mountains — but I knew that it gfows in Canterbury, on several mountains including

Hutt. It is by no means common or easy to spot, and every encounter with it is a reminder of just how much remains to be discovered about our unique mountain flora. To get back, briefly, to that giant Spaniard: this is not strictly an alpine plant, since it comes in at subalpine altitudes, and although it ranges up into the snow tussock it attains its maximum stature and status about 900 metres, at streamsides and flushes. It will grow in drier sites also, but. is then somewhat smaller. Sometimes this plant is known

as Aciphylla scottthompsonii. Under any name, it is majestic. In its huge rosettes the leaves, as stiff as swords and the colour of freshly tempered steel, may be more than a metre long. Each of the several segments terminates in a needle-sharp spine. The flower spikes, also fiercely armed, may rise more than two metres. The sight of these giant herbs — relatives of the common carrot — rising about the tussock and scrub with which they grow is one of the most impressive that our wild mountain flora can offer. •