REVIEW.

New Zealand Journal of Agriculture, Volume XXV, Issue 2, 21 August 1922, Page 125

REVIEW.

“THE VEGETATION OF NEW ZEALAND.” A study of the botanical literature of New Zealand affords convincing proof that the science, in the course of its development in this country, has been singularly fortunate in its exponents. Such men as Banks and Solander and Hookerto mention but three whose names dominate the earlier period— the vigorous school of local botanists who followed and were inspired by them, have built a splendid monument in systematic botany, while in none of the younger countries was there a quicker recognition of the profound changes which began to take place in botanical thought in Europe towards the end of last century. The new branch of the science which then arose, to which the name plant ecology has been given, and which concerns itself with the living plant in its relation to its surroundings, made such rapid strides in this country that when in 1904 the editors of the great German publication “ Die Vegetation der Erde ”* sought in New Zealand a contributor to the series, they did not look in vain. In “The Vegetation of New Zealand ” (“ Die Vegetation der Erde,” Vol. xiv, Engelmann, Leipzig), by L. Cockayne, Ph.D., F.R.S., F.N.Z.Inst., the long-recognized leader of New Zealand ecologists has concentrated the results of a quarter of a century’s study of the country’s vegetation. As no book in ' the history of botany in this country in any way closely resembles the present —the same author’s “ New Zealand Plants and their Story ” being the only work at all comparable to it— will not be out of place to give a very brief outline of its arrangement. The book is divided into four main sections, the first containing a sketch of the physical geography and climate, the third and fourth dealing respectively with the distribution and history of the flora, while the second, which makes up the bulk of the book, is devoted to a description of the plant-covering of the New Zealand area from the Kermadecs to the subantarctic islands. The reader who turns over the pages for the first time cannot but wonder at the wealth of biological detail with which nearly every one is filled, nor will his wonder be lessened when it becomes plain to him how much of it is the work of one man. To say this is in no way to depreciate the help given by any of those whose assistance is in all cases generously acknowledged, but a glance at the illustrations, which cover an extremely wide range of types of vegetation, and which are nearly all by the author himself, is evidence enough that the important plant-associations which he has not seen with his own eyes must be few indeed. It is perhaps not generally recognized how considerable a part the personal element plays in a matter apparently so little involving the emotions as the observing and recording of physical facts. No two of a hundred observers would, for instance, describe the growth-form of a plant in quite the same way, and no skill in compilation can reduce to the same value data collected from many various workers. The advantage of having before him a series of pictures of the different types of vegetation all illuminated from the same angle is one which every botanist who studies the book critically will appreciate. If “ The Vegetation of New Zealand ” possesses this advantage to a striking degree it is due less to the comparatively small area with which it deals than to the untiring energy of its author.

The majority of readers of the Journal will no doubt be interested in the book chiefly from the point of view of its relation to agricultural development in New Zealand. In the chapters dealing with the effect of settlement on the plant-covering a vivid picture is given of the changes which man, intentionally or unintentionally, has brought about since his advent, but the real contribution which the work makes to agricultural science is of far profounder significance than any presentation of facts could be. It has only recently begun to be realized how largely the methods employed in this country in the utilization of its natural resources have been those of chance. Surely such a question, for example, as to whether this or that great forest area is to be kept intact for water-conservation,

used as a source of timber-supply, or opened for settlement is one upon which the voice of science, which utters facts rather than mere opinions, should be heard. The plant ecologist, who is guided not only by the teachings of botany, but can correlate them with those of such sciences as geology, meteorology, and chemistry, must be the man qualified above all others to deal with problems which are of nothing less than national importance. Nor does his usefulness end there : wherever the process of replacing one type of vegetation with another is employed in agricultural development — the conversion of forest into pasture is the instance most familiar to New-Zealanders —the application of the principles of his science must have far-reaching effects. Chemistry by itself haS failed to show all that it seemed at one time to promise of the relation of a plant to the soil in which it is growing. It is possible to know accurately all the constituents of a soil and still to be ignorant as to what will flourish, there and what will not; but the living plant is an indicator infinitely more sensitive than anything devised by man, and already the ecologist, from a knowledge of the present plant-covering of a soil, is able to foretell, with an accuracy hitherto unprecedented, what its capabilities will be. - Dr. Cockayne is not primarily concerned in his book with the economic aspects of plant ecology, but no serious student of any of the branches of agricultural science can read the work without feeling that a new power of vision has been acquired by him■ that the different plant communities with which he has to dealpasture, fieldcrop, or forestare subject to laws of infinite variety and subtlety, and that even the partial elucidation of some of these laws will confer on agriculture gifts as yet undreamed-of. The flood of scientific literature that has been poured upon the world of late years makes it plain enough that the power to observe and record facts accurately is a far from uncommon one, and that it is one which to a large extent can be transmitted from pupil to teacher, its great development at the present day being doubtless due to the spread of university education and the endowment of research. What cannot be transmitted, and what the book under review shows its author beyond question to possess, ■ is that intuition which sees the essential unity that binds together all facts, however apparently isolated, and can catch a glimpse of the laws which they illustrate. It is the possession of this true philosophic spirit which at once lifts the work far above the level of those that are merely descriptive, and which will, we venture to think, in years to come give it the name of a classic. The style, almost without exception, is simple and lucid, while there are not infrequently hints of a rarer quality : scattered throughout the book are passages, often only a line or so in length, where, in response to the beauty to which he is obviously so sensitive, the man of science forgets himself and something of the poet stands revealed It is impossible, in conclusion, to refrain from quoting the stirring words with which the book ends : — “ . . . Finally came man : first the Maori, or it may be his predecessor; but their influence on the vegetation.was but slight. Then arrived the European. It is rather more than a hundred since he began to occupy the land, but how great the change his operations have wrought has already been told. We who now live ' in this wonderful country, and love its marvellous vegetation, have set aside sanctuary after sanctuary where the palaeotropic, subantarctic, Australian, and palaeozelandic plants, the survivors of that bitter. strife with. nature that commenced millions of years ago, can. still pursue their destinies unmolested by. their human enemies and the horde of foreign plants and animals he has let loose. Will our descendants prize this unique heritage from the dim past and preserve these sanctuaries intact ? ” - E. H. A.

Noxious Weeds.— The Masterton Borough Council has declared gorse and broom to be noxious weeds in the district under its jurisdiction. ■ Area of Commercial Orchards. -The following are the areas (in acres) of registered commercial orchards in the respective districts of the Department's Orchard Instructors : Whangarei, 813 ; Auckland, 5,061 ; South Auckland, 775 ; Poverty Bay, 374 ; Waikato, 794 ; Wanganui, 358 ; Hawke’s Bay, 2,316 ; Manawatu and Wairarapa, 815; Wellington, in; Nelson, 2,756; Nelson Central, 4,539 ; Motueka, 3,222 ; Marlborough, 852 ; North Canterbury, 2,027 ; South Canterbury, 985 ; Otago and Southland, 4,166 ■ total, 29,964 acres.

* The Vegetation of the World