NEW ZEALAND FLORA

Wairarapa Times-Age, 13 March 1941, Page 4

NEW ZEALAND FLORA

* ORIGIN AND CHARACTER FACTORS-IN DISTRIBUTION. ROTARY CLUB ADDRESS. The origin and character of the New Zealand flora was the subject of an address given at today’s luncheon of the Masterton Rotary Club by Mr W. Martin, B.Sc., F.R.G.S., of Carterton. Mr Martin is hon. botanist to the New Zealand Plant Preservation Society and author of "New Zealand Flora.” Mr Martin, by way of introduction, stated that, having made a lifetime study of -the New Zealand flora, he proposed, to devote a few minutes to discussing its origin and character. “If,” he said, “the flora of the world be compared, that of New Zealand would be found to be one of the most distinct, for over three-quarters of the plants were found nowhere else. New Zealand is today, and long has been, the most isolated land area in the world; but on more than one occasion it has had continental proportions stretching far to the east, north and south. It was undoubtedly during the last of such occasions that the ancestors of most of the present plants gained a footing and as the marginal area sank, species formerly separate were brought into proximity with consequent hybridisation and evolution of new species. Plants that apparently evolved in the ancient New Zealand area itself included the ancestors of our native spear' grasses, celmisias, lancewoods, five-fingers, brooms, flax, mahoes, wineberries, and astelias. “Other plants originated in Malaya, Polynesia. Australia, and South America,”' he said. "The Malayan element and Polynesian elements combined gave us 85 per cent of our trees just as the South American and Antarctic migration introduced over 80 per cent of our herbs. Besides the trees most of our tree ferns, nikau palm, and mistletoes came from the north. If New Zealand were divided into belts one hundred miles in width and all species in any genus of northern origin were counted in each of these belts, the figures would show a progressive decrease as we travelled south; while the reverse would be true for those of southern origin. s The Australian element has a central maximum.

“Within any given area,” said Mr Martin.” the plants arrange themselves according to conditions of soil and climate. Some will be found only on rock, in shingle, in forest, scrub, tussock, or swamp as the case may be. Five hundred of our plants are found only on the high mountain areas and many are restricted to the coast. Again, very many are confined to tlje Auckland Province while others like the tawa. karaka, or kohekohe reach south to Marlborough and still others like the nikau, rangiora, and akeake to Banks Peninsula. On Stewart Island there are no trees of beech, kowhai, teatree, kaikomako, and others found on the opposite side of Foveaux Strait. "It is clear that our plants are distributed according to law and not in any haphazard way." Mr Martin said. "Why should most of the plants above the mist lino, that is those of the upper forest and of the sub-alpine and alpine areas be Antarctic in origin when those of lower levels are sub-tropical? Then again, plants live in definite associations. so that if one plant is observed, we may be fairly sure what the others will be. The whole subject is brimful of interest and it should be the resolve of all to preserve for posterity as much of our primitive vegetation as possible, not only for its economic value in preventing erosion or in providing limber but because of its scientific interest. In any case it could be capitalised from the standpoint of scenery, for it is largely the vegetation that distinguishes the scenery of one country from that of another."