FOREST TREES

Taranaki Daily News, 21 December 1929, Page 14 (Supplement)

FOREST TREES

indigenous varieties THE HANDSOME PUKATEA. PECULIARITIES OF THE KOHEKOHE

(By

E. Maxwell.

—No. 0.)

It must always be a matter of great surprise and interest to lovers of our plant life, and doubtless to many others, that this comparatively very small country, only approximately twelve hundred miles away from the Australian continent, should have such a very large number of plants which are peculiar to it, and that they should represent such a large 75 per cent.—of the total indigenous species to be found here. When dealin rr with the classification, distribution, habitats, forms, etc., of New Zealmd plants this remarkable condition, indicating the extraordinary isolation, disassociation and dissimilarity of plant life here from that of our near neighbour Australia is constantly in evidence. Only about twenty-one per cent, of New Zealand’s indigenous plants are to be found anywhere in Australia, which is so near us, and yet seven per cent, are to be found in distant South America. This peculiar isolation of New Zealand plant life keeps coming into evidence, as it did in the last article in reference to the use of Maori names, and now again it becomes noticeable in connection with the next species to be dealt with. POROKAIWHIRI. The ‘ family Monimiaceae contains some 30 genera and 250 species and is widely distributed right around the Southern Hemisphere from Madagascar to Africa, South America, the Islands, New Zealand, and Australia. In New Zealand the family is represented by two genera and by one species only of each, both of which species are confined to this country. The first genus, Hedycarya, has about ten species; the other genus, Laurelia, has only two species, one in South America and one in New Zealand, neither of which occurs in Australia. Porokaiwhiri or Kaiwhiriwhiri (Hedycarya arborea), though a fair sized tree, cannot come under the designation of forest .tree in the sense' of great forest tree. It reaches in extreme a height approaching 50-feet and a diameter of 18 inches. It is common, in fact, very common, in forests, especially in forest margins, detached blocks, river banks, etc., throughout the North Island and much of the South Island. It has no value as a timber producer, but, especially in forest margin, is a conspicuous tree, strikingly decorative . when bearing in great masses —which it usually does to such an extent as almost to hide the rather heavy dark-green foliage—large orange-red or bright red berries. PUKATEA.

Whilst the Porokaiwhiri can at best rank low among the lesser trees, the other representative of the family is decidedly one of the great forest trees. The Pukatca (Laurelia Novae-Zea-landiac) is indeed a noble tree, reaching with its widely spreading buttressed base and great, even, white-barked bole, succeeded by distant heavy limbs topped with masses of glossy foliage, a height of 150 feet and a diameter of 6 feet. ' The P-ikatea is among the best known New Zealand forest trees, especially in the North Island, where it is abundant in the highly mixed forests. It is invariably found in swampy forests and deep valley bottoms in numbers, but usually as individual trees among other species. In addition to its grandeur as a great •forest’ tree it has a very remarkable feature,- seen in few other New Zealand trees and then only in a much lesser degree, that of wide-spreading, deep, narrow buttresses. These buttresses, which stand out all round the base and lower portion of the trunk, are from two or three to as much as five deep, and only three or four inches thick, forming between • each pair a deep, straight-sided recess large enough to hide completely a man sitting down. This buttress-forming habit, though not absolutely confined to trees which naturally grow in wet places —for instance, some of the gums have it to a degree—is distinctly in extreme form a pronounced • feature of many kinds of trees whose natural habitat is very wet oi’ swampy around, or where water frequently covers the surface and much of the base of the trees. Conspicuous instances of this deep flange-like buttressing are those of the bald cypress (Taxodium distichum) of the South Eastern and South Middle States, where it constitutes the chief or entire growth of extensive areas of what were known as cypress swamps. In such situations the bases of the trees are usually submerged and the. flangelike buttresses and high projecting parts of the roots rise above the water. The eastern white cedar —Arbor vitae (Thuya occidentalis) —of the States next to and southwards of the great lakes is . also a swamp inhabitant with most pronounced buttress growth. The western red cedar —giant Arbor vitea (Thuya plica ta)— large quantities of the over soft, weak, but very durable timber of which are being imported into New Zealand, belonging to the western area on both’sides of the Canadian and United States boundary, though not always a swamp inhabitant, develops after youth an extreme form of deep fluting* of the stem for a long way up, and has at the base great flanged buttresses. It would seem from the peculiar formation of deeply flanged buttresses and the still more peculiar way in which the roots of the bald cypress rise up in high knees above the water, that this form of growth is not only a provision for the stability of the tree in the soft material of the swamp but also a provision for air reaching the roots.

To return to our New Zealand trees, there are few such which naturally thrive in swamps. The Pukatea is really not a swamp grower, and certainly for its greater development only requires plenty of moisture in valley bottoms. Again in the case of the white pine (Kahikatea), whilst it is distinctly a swamp inhabitant, it does not reach its greatest dimensions under over-wet conditions. The only other ‘swamp inhabitant among our large or lesser trees is the Mairetawhake (Eugenia maire). This is essentially a swamp growing tree, and to a degree it develops a flanged base. The Pukatea, besides being, a very handsome tree when large, is very beautiful in all stages of younger growth. The young trees are very

stright, symmetrical, and gracefully formed, having glossy serrated leaves. The timber is valuable —strong, tough and fairly. durable—but is not greatly used because of the need of special care in seasoning, and so a large source of supply of good timber is neglected. KOHEKOHE. The Kohekohe (Dysoxylum spectabile) is one of our meet beautiful and most’ remarkable lesser forest trees. It belongs to the Meliaceae, a family of about 40 genera and GOO species, among which are many handsome and useful trees, producing timber of great value and in some cases most durable. To this family belong the mahogany, satinwood and so-called Australian cedar. New Zealand has only one representative —the Kohekohe —which is confined to it and, though common for the whole length-of the North Island, in the South Island it only, occurs in Marlborough and Nelson, where it is rare. It is usually found not far distant —a few miles —from the sea and will thrive in places quite close to the sea. Reaching a height of 50 feet, or more, and a diameter up to 4 feet, the Kohekohe is, with its wide-spreading branches, clothed with exceedingly handsome, • very large, glossy, vivid green leaves up to 18 inches long, composed of about four pairs and terminal of large, separate leaflets. It is altogether a most beautiful and attractive tree.’ -The leaves are very Melia-like and in size and form are somewhat suggestive of those of the Puriri, though longer and not so dark or wavy. Neither is suggestive of New Zealand types. The Kohekohe -in the main belongs to the forest margins of coastal areas. In such situations it frequently forms belts, where it predominates, within and to the outer edge of the forest margins, and occasionally forms pure stand groups. In such cases through the widespreading brandies and dense foliage so complete a canopy is formed as to prevent any undergrowth, so giving an absolutely clear forest floor, in great contrast to the ordinary New Zealand bush. In such conditions in the right season—May to July—the remarkable and unique feature of the Kohekohe is very noticeable, that of the long, slender, drooping, wide-spreading panicles of waxy-white flowers' . springing direct from the hardwood of the trunks and limbs. The flowers are followed by large —about the size of small figs—green, somewhat pear or fig’ shaped berries. Apart from the great beauty of the tree, this extraordinary feature — the production of the flowers from the bare hardwood of the tree—singles out the Kohekohe from all other New Zea? land trees. . The timber is one of those timbers that have been passed over and shamefully wasted. It is a very valuable timber for many purposes. It is light in weight, straight in grain, fairly soft, easily worked, strong, fairly durable when exposed to moisture, and very durable when not. It has a handsome grain and bright- sheen and is highly suitable for furniture aiid decorative purposes.