CONSERVATION IN CANADA. O.M. McConkey. 1952, pp. 215. J.M. Dent & Sons (Canada) Limited, Ottawa. $ 3.50.
One result expected from recent technical assistance programs of international organizations and single nations was that professionals, after a period spent in dealing with problems in varied parts of the world, would return to their own countries with a keener, more vivid and realistic grasp of world lessons applicable to their homelands. Another hope was that the teams of technicians from many nations and races would open the eyes of specialists to the fact that conservation is one indivisible whole, not a mere aggregation of many distinct units having some general similarities each to the other.
This compact little book indicates that technical assistance programs may indeed develop in such a way that the nations which render assistance receive as well as give. Certainly the author, a professor of field husbandry, sees the Canadian scene as a whole, and criticises unsound trends in land use in his own country in the light of such final results of lack of conservation which he has seen in China and elsewhere in the course of foreign aid tours.
Yet this is much more than an appeal to fear, although the application of this point to the Canadian problem is not forgotten. Full emphasis is given to techniques already proved to be sound for productive and permanent use of land and water - more forestry and better utilization of wood, more grassland agriculture, more conservative grazing and the rest. The main techniques - windbreaks, crop rotations, contour cultivation and the like - are illustrated in terms of Canadian policy.
The general reader, and particularly the citizens who make public opinion in Canada, have here a readable, sound and convincing basis for an over-all program to carry out the author's deep belief that conservation, using available methods, must replace extractive use; a unified national plan must supersede, uncoordinated programs; Canada, a rapidly developing country, must recognize that great opportunity still exists, for so much of its wealth of resources is yet undamaged. And the same opportunities and obligations exist in many other countries whose natural resources have still to be fully developed.
MANAGEMENT AND CONSERVATION OF VEGETATION IN AFRICA. A Symposium. Bulletin No. 41 of the Commonwealth Bureau of Pastures and Field Crops. 1951, pp. 96. Illus. Commonwealth Agricultural Bureaux, Farnham Royal, Buckinghamshire, England. 10/6d.
This is an unusually good description of the major vegetation types or ecological zones in African countries of the Commonwealth and of what is happening to them now that, through control of human and animal diseases, the native populations and their domestic herds have greatly increased. In brief, this has put great pressure on the land, and degradation of forest, savanna and veld areas has proceeded rapidly.
Shifting cultivation accompanied by burning has destroyed or greatly reduced the productive capacity of vast expanses of once valuable forest while on steep mountain slopes there has been a senseless wastage of soil. As the need for land has increased, more and more forest has been cut the debris burned, a crop, or occasionally two or three, taken and the field then abandoned. Where periodic burning does not occur, the forest can reestablish itself and if the fallow period is long enough and the slope not too steep, the soil may be rebuilt sufficiently in seven to nine years for the process to be repeated and another successful agricultural crop taken. In too many places periodic burning has caused a grave diminution in fertility, especially where coarse grasses have encroached on the abandoned fields and there has been a shortening of the forest fallow period because of the demand for land. Extension of poor agricultural practices into semi-arid and arid areas has become a serious factor in soil erosion.
In general, only a start has been made in reserving those areas that will be required to produce the necessary wood products and to con serve water supplies. In Tanganyika, a few large grazing reserves have been established. In Africa, through studies at a number of experimental stations in representative areas, sound principles for land use grazing management and veld burning have been developed. Of major importance in grazing management is provision of a rest period during the growing season of the grasses. These rest periods vary from one type to another. It is important that there should be appropriate intensities and seasons of grazing and of other phases of systems of management to meet the special requirements of each vegetation type.
Burning in spring after rains have fallen about every two years has a place on sour veld (areas where grass becomes unpalatable after maturity). At other times and in sweet veld (areas where grass remains palatable after maturity) burning is damaging. Burning can also be used every two years, after rains in the spring, to aid in control of thick cover of thorn scrub. Dense stands of such scrub (acacia) are useless from a grazing and water conservation standpoint.
PLANNED MANAGEMENT OF FORESTS. N. V. Brasnett. 1953, pp. 238. George Allen and Unwin Ltd. London. £1.
FOREST MANAGEMENT. H. Arthur Meyer, Arthur B. Reeknagel and Donald D. Stevenson. 1952, pp. 290. The Ronald Press Co. New York. U.S. $ 6.00
FOREST POLICY. William B. Greeley. 1953, pp. 278. McGraw-Hill Book Co. New York, Toronto London. U.S. $ 5.50.
Two books on forest management have recently appeared, both remarkably well presented and arranged and the fruit of their authors' long experience. While they deal with the same subject, they differ to such an extent as to justify comparative study.
The first by N.V. Brasnett, Lecturer in Forest Management at the Imperial Forestry Institute, Oxford, is written in the classic manner. Part I contains a short but lucid account of all that should be known about forest stands - how they increase in value, the considerations on which management of a forest should be based, and the possible goals of management. The writer then takes, one by one, the various parts of an ideally arranged management plan and shows how they should be operated. Part III is a historical account of management methods in western Europe, which throws light on the systems explained in Part II and gives the reasons why they have come to be more or less satisfactorily developed.
Forest Management takes another line of approach. It is the work of three American foresters holding very different posts - one is Professor of Forestry at the Pennsylvania State College, another Technical Director of Forestry with the St. Regis Paper Co., and the third Research Adviser in Forestry to the Office of Foreign Agricultural Relations, U.S. Department of Agriculture. Their aim is explained in the preface:
"The present textbook is a definite departure from the classical European approach. The authors have attempted to bring together in a single volume the basic material on forest management, from the standpoint of its applicability to American forest practices. The chapters in parts I and II are devoted to the general problems of forest organization. Thus, in the traditional way, these problems have been segregated from the specific problems discussed in part III, which is concerned with the principles and methods of forest regulation, that is, the principles and methods used in determining the allowable cut. Rigid methods of forest regulation and elaborate formulas for the determination of the allowable cut are considered a thing of the past. The fourth and last part of the book is devoted to management plans. Typical examples of management plans for forests of various sizes, located in various parts of the country, have been included in only slightly abbreviated form ..."
Thus the second book deliberately reverses the approach used in the first. What must we think of it? Is it true that rigid methods of forest regulation and elaborate formulas for the determination of allowable cut have become useless?
By rigid methods presumably must be understood methods of regulation by area. But Mr. Brasnett tells us that the more rigid of them, for instance the 'méthode du tire et aire', are still in use over large tracts of forests in certain territories under British administration and that, given a certain amount of flexibility, they prove very useful and introduce at least a minimum of order where otherwise there would be chaos - but it must be admitted that the key qualification is flexibility. Nevertheless, the principles of the methods remain sound. Area methods are indeed even more widely used than would appear from Mr. Brasnett's book; he classifies as mixed area and volume methods, for instance, permanent periodic block and revocable periodic block methods where the volumes, incidentally estimated for only a small part of the forest, are really only a guide to the application of management regulations. Likewise, the control method, as those who advocate it strongly claim, is essentially an area method.
It may also be said that the old formulas for the determination of allowable cut by volume are not in fact over-elaborate but rather quite simple and precise. Theoretically they may be, and often in fact are, useful for forests about which very little is yet known.
However, we must agree with the authors of Forest Management that modern methods of inventory and forest mensuration that can be applied even to very large forests help considerably to curtail the empirical period and to break through the chaos to which Mr. Brasnett refers. They also make it quite possible to estimate the volume which can be cut annually or periodically in a particular forest on a sustained yield basis. The distribution of the cuts in time and space for the production of the necessary volume may be governed solely by silvicultural and economic considerations.
These calculations or estimates are based on three factors, the second and third of which are closely connected - the standing volume and present increment of the particular forest, which modern techniques can determine precisely or at least with a known degree of precision, consideration of the normal forest; and the goal which the forest owner is seeking to attain and the speed with which he desires to attain it.
These are the three factors that Forest Management deals with at some length. Consideration of the normal forest takes up quite a sizeable portion of the book, and rightly so, the writers dealing first with normal even-aged forest and then with normal uneven-aged forest.
The relationship between the third factor and the second is also very important. Once a forest owner has decided to manage his forest, that is to say, to bring it under sustained-yield regulations - and the authors of Forest Management here make a useful distinction between management and exploitation - the policy he proposes to adopt will actually depend on his conception of the normal forest that is sooner or later to replace the growing stock now occupying the forested area.
In the case of even-aged forest determination of rotation will be the essential factor in this conception, and the work of the three American authors clearly shows how rotation affects yield and gross yield as well as the annual forest rent per acre obtained in the forest. The chapter on uneven-aged forest clearly evaluates what is known of the composition and growth of normal uneven-aged high forests, but unfortunately does not indicate how far the owner of such a forest can influence the quality and quantity of the products it yields. The theory of rotation is, in fact, not apposite to uneven-aged forest and should normally be replaced by that of maximum diameter up to which trees are desired to grow.
As the writers point out, much research has yet to be done on the normal composition of uneven-aged forest. Studies on virgin forests, as the section devoted to this subject shows, would be very useful for the advancement of knowledge, but they are unfortunately few in number and it must be admitted that, if excellent results have been obtained from the systematic management of certain uneven-aged forests, this management has so far been entirely empirical, in the sense that the ideal has not yet been defined.
After the brilliant work in the first three parts of Forest Management a reader may confess himself somewhat disappointed with the last part on working plans. No doubt these plans illustrate a profound knowledge of the physical and economic conditions of the forest to which they are applied. Doubtless, also, it would be too much to expect to find precise directives, as would be possible in the case of forests subjected to working plans that have been revised again and again. Yet one is struck by the fact that practically the only concern of the writers seems to be to improve the forest. Concern with improvement is perfectly justified, but forest improvement is not in itself enough to guarantee sustained yield, normal distribution of age and diameter classes is also required - that is to say, the objective must be normalization of the forest. It is not easy to discern w hat action has been taken under these plans to achieve this end, and it is even difficult to deduce whether the aim is to establish even-aged or uneven-aged forests.
One of the plans given, that for the forest belonging to the Hassel and Hughes Timber Co., Wayne County, Tennessee, is of interest from another standpoint. This relates to a forest of 49,000 acres (19,600 hectares) recently purchased by a company that wants to get all its wood supplies from it. It has been badly depleted by previous fellings and can be improved and brought again under sustained-yield management only at the cost of substantial savings on increment. Such economies imply a definite drop in the quantity and, above all, a substantial decline in quality of the mill's supplies. Instead of being discouraged by this prospect, the Company has completely transformed its internal organization so as temporarily to rely on only a small amount of poor quality wood, without any cut in employment. This is a remarkable example of integration of the forest with the wood-using industry, a real achievement of sound forest policy in the true sense of the term. Admittedly, it is forest policy at the forest level. But, is not forest management essentially the local application of forest policy, and is not the main instrument of national forest policy the policy applied to each individual forest?
For this reason it seems advisable to review along with these two books a third of equal interest entitled Forest Policy and written by the Vice-President of the U.S. West Coast Lumbermen's Association.
Although its first brief section is devoted to the origins and methods of forest policy, the book is essentially a history of national forest policies. The second part, in effect, describes the development of policy in various countries selected from among the most representative, with particular emphasis on the more recent phases of development. Well documented this section of the book is of considerable interest, an effort is made, generally with success, to bring out the characteristics of the forest policy of each country.
Of still greater interest is the third and more important part of the boor, which gives an account of the progress made in United States forestry and, in its last chapter, deals with that country's current problems. This progress has many striking features, and Mr. Greeley rightly makes first mention of the development of education, not only among forestry technicians but also among the citizens of the country, in under 60 years, they have become conscious of the national importance of the forest, as a result of methods employed by the Federal Government and by the States, the universities and many large associations including the wood industries. This close cooperation, which is apparent in many other sectors of the forest policy, and in particular in the control of fire - the chief enemy at the beginning of the century of the American forest - is one of the best and most rapidly developed features of American forest policy. Outstanding progress has also been made in forest research, with the result that the United States is now one of the most advanced countries in this field.
But the most interesting thing about this policy - and this brings us back again to the pages of Forest Management - is perhaps the development of large forest-owning industries and the integration sought between the industries themselves and the forests that feed them.
However, the same thought passes through one's mind on closing Forest Policy as on reading the last part of Forest Management. Technical progress in the United States in the field of forestry is considerable; the knowledge of how to apply sound forest policy methods is steadily growing and their complexities are being ever better analyzed. Nonetheless, felling practices can still only be regarded as good or very good on 23 percent of the whole of what is called commercial forest and on 8 percent of private commercial forest, representing three-quarters of the total forest area. Cutting methods are bad or destructive on 72 percent of small private woodlands (under 5,000 acres 2,000 hectares), which in turn represent three-quarters of the privately-owned forest area. Even in the case of larger private forests, only 28 percent is under sustained yield management.
These statistics, it is; true, are for 194546, and substantial progress is known to have been made since then. But progress in this particular field takes time. Despite the efforts made, the learning displayed and the results obtained to date in the United States, there still seem to be many undiagnosed difficulties yet to be overcome before the extensive program can be achieved which has been mapped out by the heads of the U.S. Forest Service for ensuring the increasing timber supplies required for the country's future development.
