The items appearing here arc condensed from newsworthy material collected by FAO staff or submitted by correspondents. FAO assumes no responsibility for statements and statistics in items accepted in good faith from contributors.
Australia
· The Forestry and Timber Bureau indicates that a forestry investigation of the more readily accessible parts of the vast Northern Territory of Australia has been under way since 1950 and has now been reported on. The cost of importing timber into the Territory is very high and, because of the interest in development of industry there, the production of timber in that region becomes increasingly important.
In the neighborhood of Darwin, the average rainfall is about 30 inches (152 cm.), but inland it falls off very rapidly and conditions are unfavorable to tree growth. In the area examined there are four broad glasses of forest:
1. an open type of eucalyptus forest is the dominant type, but the area which can produce commercial timber is highly restricted;2. patches of cypress pine on light soils within the eucalypt forest;
3. dense pure forests of paperbark (E. fitzgeraldi) on swamplands and along streams;
4. small patches of rain forest on particular sites along streams and on the fresher swamplands.
Exploitation of the forests for mill logs began about 1870 and was greatly speeded up during the second world war resulting in working over a large area of the better forests. Even so, the cuttings would not have had a serious effect if they had not been followed by annual burnings, an established and accepted practice by both white and aboriginal inhabitants. The fires have resulted in serious depletion and deterioration of the forests, and regeneration is not adequate. In only a few places has any attempt been made to prevent the annual burning. In general, then, the picture is depressing.
There are, however, some areas with real future possibilities, given protection from fire and sound management, and the report under reference proposes studying the silviculture of the species having likely commercial value, testing the suitability of exotic species for planting, selecting and proclaiming areas to be dedicated to forest production and introducing sound forest management on the proclaimed areas. If such a program is vigorously pursued, it is expected that the forests of the Territory can be made to produce at least the local forest products requirements.
Austria
· The Austrian Federal Ministry of Agricultural and Forestry Economy has released the first results of its Forest Inventory.
The Forest Inventory distinguished two categories of forest administration, the first of which comprised managed forests, the other being unmanaged forests. The latter consists mostly of small-sized wooded areas. The ratio of managed to unmanaged forests is one-third to two-thirds.
The Forest Inventory had as its prime object the surveying of the unmanaged forests since the study of this important portion of the forest domain hitherto relied on estimations only.
1. The total wooded area of Austria was found to contain roughly 3.3 million hectares.2. The area of economic (commercially usable) forests is 2.7 million hectares. The rest, particularly in the higher mountainous regions, can be utilized commercially only to a restricted degree, such as protective forests, forests in or with grazing land, or reserved forests where felling is prohibited outright (Bannwald).
3. Clear-cut and insufficiently wooded forest areas which urgently need reforestation or re-stocking total 165,000 hectares. Hence, in addition to the areas normally to be reforested, about 20,000 hectares per annum, a further 20,000 hectares more per annum will, in the course of the next eight years, have to be reforested.
4. Concerning the proportion of age classes, small forests clearly show the preponderance of class III (40 to 60 years), whereas the next classes, IV, V, and VI (30 to 120 years) are more or less on the decline.
This seems to indicate that the higher age classes have been exploited to a strong degree; on the other hand, it opens up hopeful vistas for the future.
If classes V and VI (80 to 120 years) are considered jointly - this appears justifiable since the average age of maturity can be assumed to be 100 years - the actual ratio of age classes is in no way alarming. It must, however, be emphasized that this is true only as far as the area ratio is concerned.
Examinations of forest areas over 50 hectares in size have, so far, shown approximately normal proportions of age classes.
5. The average standing timber on the whole of Austria's forests had formerly been computed to be roughly 150 m³ per hectare, a figure which no doubt is too low.
6. The initial result of the Inventory shows the volume of permissible yearly fellings to be approximately 8.5 million m³ This is relatively near the annual increment figure revealed by the 1935 Forest Statistics.
Canada
· The report of a Royal Commission on Forestry, which was appointed to examine generally the forest resources of Newfoundland and their fullest development and utilization, recommends that forest policy in the Province should aim at the maximum possible expansion of the pulp and paper industry, and that all other industrial developments based on use of forest resources should be assessed with that objective in view. The Commission, which included Mr. Roy Cameron, formerly on the FAO staff, recommended that a new body should be set up to be known as the Newfoundland Forest Protection and to be administered by a board of directors to be appointed by the Lieutenant-Governor, and consisting of a chairman, who shall be the Minister of the Department of Government for the time being in charge of forestry affairs; a vice-chairman, who shall be a representative of one of the two existing pulp and paper companies in the Province; one member who shall be a representative of the other of the two pulp and paper companies; one member who shall be a representative of the saw milling and other smaller timber interests; and one member who shall be the Director-General of the N.F.P.A. to be appointed, on the advice of the board of directors, by the Lieutenant-Governor. The report, which extends to some 240 pages, also recommends a Newfoundland Forest Act to give legislative basis for a provincial forest policy to be officially approved as government policy, but suggests that the passage of such an Act should be deferred until the new forest inventory is completed and the time ripe for the establishment of a Newfoundland Forest Service, which, in the Commission's opinion, should not be later than 1960. In the interim, it is stressed. the necessary legislative action should be taken to implement the other recommendations contained in the report.
· An article in the Convention Issue, 1956, of the Pulp and Paper Magazine of Canada deals with Fertilizers in Forestry and Their Use in Hardwood Plantation Establishment. The economies of forest management, the article says, have been progressively changing over the years so that presently we are able to conduct more intensive cultural practices than ever before. With today's high level of wood consumption, interest is rapidly shifting from the view of maintaining wood yields to that of increasing production per acre of forest products. This change in viewpoint may well be heralding a new era of forest management.
One forestry practice which requires further investigation as a means of increasing wood yield is the use of fertilizers. Until recently, research in this field has been limited. When the use of fertilizer in forestry is first discussed, many think only of spreading fertilizers on responsive sites. However, fertilizers may have very specific uses in forest management.
1. Nursery management. Fertilizer usage in nursery management is a relatively common practice and is generally considered an important part of the management plan. This is reason able since continuous nursery cropping of high yields of both stem and root is a degrading practice.2. Establishing plantations. Seedlings out-planted initially experience severe competition which is detrimental to growth. Hardwood seedlings are particularly susceptible to competition and plantations often eke out an unsatisfactory, unprofitable existence. The effect of competition is often primarily nutritional and appears to he largely offset by an application of fertilizer. Such an application may significantly increase wood volume and decrease rotation age of newly-established plantations.
3. Disease reduction. Forest pathological literature frequently cites eases where healthy trees are less susceptible to diseases than unhealthy ones. Proper fertilization of unhealthy trees may reduce their disease susceptibility.
4. Increasing seed yields. Proper fertilization of trees has been shown to increase significantly seed production and produce significant quantities of seed even in poor seed years. This treatment may be of value in areas of poor natural regeneration by treating selected seed trees so that a seed crop would be present at the time of cutting. In any ease, such a treatment should be of value to forest geneticists and nursery managers for increasing seed yields on select parent trees.
5. Forest fertilization. Few sites have soils which are optimum in fertility, and many sites are deficient in certain nutrients. The most deficient sites are generally those with coarse texture soils, and more particularly those coarse textured soils which are severely burnt-over. Very significant increase in tree growth has resulted from fertilizing such soils with potassium, magnesium, and nitrogen. Other elements, including some of the minor elements, will be found to give marked increases in wood volume on different sites.
Significant increases in wood volume as a result of fertilization have led research workers to study economical methods of applying fertilizers to forests. Aerial application has been recently investigated in the United States by both Syracuse University and the University of Washington. These experiments were not designed to yield detailed costs, but results indicated that the methods were highly satisfactory from a distribution standpoint and probably the only feasible way of getting fertilizer on many types of forest lands.
Ceylon
· The FAO Regional Forestry Officer (C. S. Purkayastha) recently visited the huge organization (Galoya Development Board) that has been built up for the Galoya Development Project, involving dam constructions as well as the development of new colonies. One dam is completed and new ones are projected. According to the scheme, each household is given 3 acres (1.2 ha.) of highland for homestead and growing cash crop and 2 acres (0.8 ha.) of paddy land. Talking with the Chairman of the Development Board, the Regional Forestry Officer discussed the question of establishing communal forests to meet everyday needs of the new colonies such as fuelwood, fence posts and wood for agricultural uses. The present task of forest officers was primarily soil conservation in the catchment areas and extraction of utilizable timber from the areas being cleared with tractors. The question of permanent communal forests would certainly be pursued. The villagers would not be using electricity for the domestic needs, as this was not a practical proposition.
Mr. McVeigh, an FAO expert, was redesigning a sawmill and increasing its production to meet the large demand of timber for the Development Board. Expensive equipment had been produced, including a pressure cylinder for preservation treatment. Some small teak trees had been brought into the sawmill from one of the 30 to 40-year-old plantations which had been cleared in this area Though the trees had not attained a very big size, the timber appeared to be quite attractive and could in any ease meet the furniture demand of the Board.
" Having seen the timber, I do agree that introduction of this species under exotic conditions is quite a justified effort."
Elsewhere, the mechanization introduced by Mr. Letourneux, FAO expert, was inspected. The present plan of afforestation of about 2,000 acres (800 ha.) a year against a previous annual program of 300 to 400 acres (120 to 160 ha.) is a distinct achievement. Available land is getting scarce and now plantations are being created on grazing land mechanized plowing. The exotic grass Brachiaria bizantha, a hardy species with good fodder value, is being introduced in Ceylon, with win- belts at intervals composed of species of Eucalyptus saligna, Cypress and Acacia mollissima. This seems to be the first instance in the region where forest services are taking an active part in improving pastures, with the windbelts also serving as a source of fuelwood supply.
Chile
· An FAO officer, C. W. Scott, who lectures on utilization at the Forestry School, University of Conceptión, writes of a visit to the demonstration center at Llancacura (see Unasylva, Vol. 9, No. 2).
"I hired a four-seater Stinson plane from the Flying Club of La Union to take two fifth-year students, engaged on cruising, and myself over the Llancacura Reserve. We flew over the forest for about half an hour in good weather but at too low a height for satisfactory sketch-mapping. We identified all the main topographical points and got a good grasp of how very steep and broken is much of the terrain in the west of the Reserve, as the cruisers have learnt the hard way, on the ground.
The stand in general looked very uniform. Clearly it would be easy to identify the main species and separate them by observations or photographs when the "ulmo" (Eucryphia) is in white flower, or the "tineo" (Weinmannia) in red flowers; and the large "coigüe" (Nothofagus dombeyi) is probably always separable by its size and crown form, associated with horizontal branches. This type of flight is well worth repeating, to interest and reward keen students and others."
Mr. Scott has also prepared an article on the Softwood Lumber Trade of the Southern Hemisphere for publication in Spanish in Chile Maderero, the journal of the Chilean Lumbermen's Association (Corporación Chilena de la Madera), Santiago, which appears every two months.
A similar article on the export of "pino insigne," Pinus radiata, from New Zealand to Australia, and the lessons for Chile, appears in the first issue of Luma, a new review being published by the Associación Chilena de Investigaciones Forestales (Chilean Association of Forestry Research).
Based on a lecture given at the University of Conceptión, the article states that to understand the broad picture of the sawn softwood trade in the Southern Hemisphere it is necessary to remember two vital points:
(a)
The average quality or grade of lumber cut from trees such as the Paraná pine (Araucaria angustifolia) of Brazil and the "kauri" (Agathis australis), "rimu" or red pine (Dacrydium cupressinum), "matai," "totara" and other species of Podocarpus of New Zealand (similar to the mañíos of Chile, which are other species of the same genus, Podocarpus) is very different from the average lumber that can be cut from the usual "pino insigne" plantations. The difference is especially great when the pine plantations are still young and if they have not been thinned and pruned early enough to reduce their knots and increase their proportion of clear lumber. The Paraná pine, "kauri," "rimu," etc., are usually cut from large trees in natural forests of great age, many decades or centuries old. Naturally such trees yield beautiful clear lumber, free of knots, at least in the outer zones of the lower lengths of the tree bole. It is a very different matter to sell such high grade lumber and to sell "pino insigne" from young trees, especially if the trees have not been pruned and if the lumber has not been well sawn, dried and graded. Yet both New Zealand and South Africa have shown convincingly how much can be made of even relatively young "pino insigne "if it is well handled. The technical literature of both these countries, and that of the southern yellow pine (Pinus palustris, P. taeda, P. echinata, and P. elliottii) of the United States, should be studied in Chile and their techniques adopted.
(b) Softwood lumber exports and imports may be affected by such factors as return freight facilities for the steamers which carry the lumber, i.e., whether these steamers can find attractive cargoes for their return voyages, and by exchange restrictions, trade agreements and other factors outside the technical qualities and price of the lumber itself.
The great volume of "pino insigne" now planted and growing as fast as it does in Chile presents a great opportunity and responsibility. Few doubt that it has a great future if disaster from disease and fire is avoided by good management and good fortune. The profits, for the plantation owners especially, may depend greatly on what action is taken on the warnings from other countries to which this article invites attention. Proper tending of the plantations and good sawing, drying, grading and, where necessary, preservative treatment are as important in Chile as they have already proved to be in New Zealand and South Africa. Selling prices must be competitive, of course, and in this matter Chile has advantages to exploit and obstacles to overcome.
Argentina, Peru, Uruguay and Bolivia, potentially rich neighbors of Chile, which lack adequate softwoods, appear to be good markets to try to develop. The basic attractions of well-prepared "pino insigne" are that it is light, strong, very easy to dry and work, durable when treated with preservatives and very easy so to treat, stable and relatively free from splitting, warping or abnormal compression wood. Such abnormal wood gives appreciable trouble in Paraná pine and the southern yellow pines of the United States, vice many excellent studies by the Forest Products Laboratory, Madison, United States.
The article mentions in conclusion that the Chilean softwoods other than "pino insigne," the native Chile pine (Araucaria araucana), "mañíos" (Podocarpus and Saxegothaea) and "alerce" (Fitzroya) are very attractive timbers of high quality. The supplies of Araucaria araucana are very limited, unfortunately, and those of the "mañíos" are often effected by the poor shape of the trees, in certain zones, with many stellate or deeply fluted boles. However, much can be made of these native woods, within the available supplies, by good milling and grading. With such handling they could find wider markets and better prices. As in New Zealand, however, so in Chile the main softwood problem and hope for the future lies in "pino insigne" and similar exotics. A variety of such trees should be planted, to reduce the risk of disease inherent in forests of one species, whether planted or natural, native or exotic.
Colombia
· At the last Arbor Day festival celebrated throughout the country, 1.5 million young trees were distributed to the public to schools. An interesting feature was the coverage of 13 cities by four airplanes supplied by the Government, delivering small trees for planting to one city, receiving other trees and carrying them to the next city as a symbolic and fraternal message of love of trees.
At present, there are four Forestry Commissions operating in the country, each with a $60,000 budget, a forest engineer in charge, four supervisors of forest nurseries, and twenty-five workmen. Each Commission operates in a catchment basin where programs for the development, protection and conservation of natural resources are under way. Two hundred thousand trees are planted per year after a carefully studied selection of species.
Each Commission, within its radius of action, is working to set up regional tree nurseries in collaboration with mayors and school teachers, in this way implementing a tree-planting program. Each Commission also supervises forest extraction operations with a view to getting them on to an efficient basis and is in charge of the public domain lands It is probable that, in 1966, four additional Commissions will be set up, thus expanding such forestry work to over half of the country.
Cuba
· An increasing interest in forestry is taking place, activated by lectures and press, radio and television campaigns. The Sociedad Silvícola Nacional, with the effective collaboration of the Colegio de Silvicultores and the Ministry of Agriculture, is developing a forest program under the name of bosques comunales (community forests) There are preparations for planting ten million seedlings of several native and exotic species, including Eucalyptus, Casuarina, Tectona and Khays. The planting of Bursera simaruba on sandy soils of the coastal region is being investigated
The Sociedad Silvícola Nacional is granting portions of the bosques comunales to primary schools for their attention and care. A prize of US $50 has been offered to the group of students who, over a period of two years, show the best results, thus stimulating the pupils' interest towards trees.
Ecuador
· La Forestación Artificial en el Ecuador Central, by Dr M. Acosta-Solis, Director of the Istituto Ecuatoriano de Ciencias Naturales, deals with the arid and semi-arid inter-Andean region of Ecuador; the booklet describes the ecology, soils, and natural vegetation as a basis for tree-planting research. It goes on to describe the coniferous and broad-leaved species tried, with special attention to pine, cypress, araucaria, eucalypts, casuarina, acacia, willow, and poplar, and several less generally used species. There is an important section on techniques of planting, with emphasis on spacing. There are included useful tabulations of seed source, germination, and survival of over 100 species, based on Ecuadorean experience. Summaries in Spanish, English, French and German are included.
Egypt
· In its efforts to improve the forage resources in the west desert, particularly in the 26 kilometer strip along the Mediterranean Sea, the Government of Egypt, in co-operation with United States International Cooperation Administration has set aside a 24,000-acre grazing area to be used for demonstrating different methods of grazing management and range improvement. Although the program is not yet fully underway, some rather interesting developments have taken place. A visit was made to this area by delegates to the first Session of the FAO Working Party on the Development of the Grazing and Fodder Resources of the Near East, held in Cairo from 14 to 21 March. The working party is made up of agronomists, animal husband-men and a few foresters
Five thousand acres of the Ras el Hekma Experimental Range have been given semi-protection, or rather, considerably lighter grazing during the past three years. Although the area receives only 160 millimeters of precipitation, the vegetation has made remarkable response to this semi-protection treatment Plants, which under the usual pattern of grazing, are mostly unseen, having been grazed to the ground line, are now 0.26 to 0.5 meter tall and producing large quantities of forage. One observer has estimated that if only 60 percent of this herbage is eaten by grazing animals, the total production will be several times greater than from similar areas where utilization is complete. In addition, the cover of vegetation is increasing over the soil for greater protection against wind erosion.
Another interesting phase of the experimental program is the seeding of productive basins and drainage bottoms, where there is greater accumulation of soil moisture, to desirable grasses and legumes. The first crop from these fields is being cut for hay each year and stored for emergency periods of short forage supply. The fields will then be grazed along with the other part of the range.
The over-all plan for this experimental range is that several kinds of good management practices will be tried and compared. All of these will be practices which can be adopted by the people and their herds who are living in the area. As a matter of fact, local people and their herds will provide the animals used on the area. Detailed research will not be carried out but rather the program will involve demonstrations of how the use of this kind of grazing land can be improved to the benefit of the land and the owners of the livestock. It is the sort of thing that is needed in many countries to create interest among the people in improving their practices of land use.
Austria
· An inspection report has been received on afforestation work in Burgenland. This report pays special attention to Ailanthus altissima (syn. glandulosa).
In the Provincial Forest Nursery at Weiden-am-See, various tree species suited to the continental, dry climate of Burgenland are grown, used especially for the planting of shelterbelts in the northern districts of Burgenland. Besides poplars and various maples, a number of exotic species such as Ailanthus are raised.
Ailanthus is sown relatively late (from 20 April to 10 May), as the seed requires warm, dry soil in order to germinate. Wet and very salty soils are not suited to the species. The seedlings are transplanted at the end of October and beginning of November in the first year. They are lifted by machine, because the plant develops a tap-root that is bigger than the aerial part; lifting with a specially constructed machine is very simple and no harm is done to the root, whereas damage is very likely to in lifting by hand.
The plants are set out in the shelterbelts in the second half of November. In its first years, Ailanthus is susceptible to injury from frost; in particularly cold spots it dies back, but the roots remain sound and readily sprout again. No susceptibility to serious pest infestation has been observed.
A visit was made to shelterbelts established on agricultural land. There are four shelterbelts, about 4 to 5 kilometers long, set at intervals one behind the other with a spacing of 1 kilometer between. The width of the individual shelterbelt, of mixed Ailanthus, robinia and maple, varies between 30-50 meters.
Ailanthus manages to live on the worst soil. Unlike robinia, it helps to form a humus layer in a short time through the shedding of its leaves. The rate of growth is similar to that of robinia, yet at the time of the inspection it appeared to be the most thriving tree of all the plantations.
Germany (Eastern)
· Progress in forest operations, as in all other fields of human technical activity, depends not only on the choice of good equipment but even more on its correct use and maintenance, as well as the application of the proper working techniques. The need for better training of forest labor is becoming generally recognized, and in our mechanical age, many countries devote increasing concern to problems of work efficiency through scientific investigation and workers' training.
Two interesting publications from Eastern Germany, both intended to familiarize the practical forester and woodworker with advanced equipment and techniques, have recently been brought to our attention. Beiträge zur Technisierung der Forstwirtschaft (Contributions to the Mechanization of Forest Operations) 1953, pp. 175, and Die Motorkettensäge, Handbuch für die forstliche Praxis (The Chain Saw, Handbook of forestry practice) 1954, pp. 148, both well illustrated and written in plain language to be easily understood by the worker. They are two good examples of how technical information and instruction may be passed on to personnel engaged in forest operations.
Guatemala
· Decree No. 543, which appeared in the Official Gazette of the Republic of Guatemala on 9 February 1956, established the system of Unidades for the exploitation of the national forests and for the development of forest industries.
The system of Unidades is similar to that to be found in Mexico (see Unasylva, Vol. VII, No. 2, p. 50) and their establishment has been declared a public service. Private forests which happen to be situated within the forested area set aside for a Unidad are only to be incorporated, however, by the request of their owners. The State is to maintain a very strict control not only over the setting up of each Unidad, which will be preceded by a thorough investigation of the management problems involved, but also over their actual operation. Both forest officers and forest rangers to be attached to the Unidades are to be nominated by the Government, which will pay them from the credit account of the Unidad.
The same decree prohibits the export of roundwood or hewn timber. It authorizes the granting of exemption from import dues on material to manufacturers wishing to start up forest exploitation or to set up a Unidad.
The decree also adopts the metric system for the measurement of timber.
Hungary
· Higher education in forestry is provided by the Sopron University for Forest Engineers. The courses last four and a half years and, having passed the examinations, the students are awarded a forest engineering diploma. Specialized training was given for some years by this University but, recognizing the disadvantages of this education, in the school year 1954/55 the University returned to general forest engineer training.
Secondary high school training is carried on in two technical forest schools, the courses lasting four years. To enter one of these schools, eight classes of the primary school have to be passed and, after finishing their studies - generally when they are 18 - the graduates obtain a certificate which is of the same value as that given by non-specializing general secondary schools.
The training of skilled workmen is carried on regularly; for instance, for the handling of motor saws technical courses are arranged by the National Directorate of Forests; the participants live in a training institute and also receive payment during the course.
For the more highly educated, secondary school and lower-grade school professional men, forestry refresher courses are provided by the National Directorate of Forests. Thus in a few weeks the participants in these courses may obtain some idea of the results of investigations and of important theoretical and practical problems of forestry dealt with since the time they were qualified. Private owners who only have small woodlands are given professional training at similar courses.
India
· The Government of India has just published the report of the third session of the Central Board of Forestry, which was held in the State of Madras in May 1955.
This meeting was particularly important because it had to examine especially the part reserved for forestry in India's second Five-year Plan (1956/57-1960/61). The Board has approved in the main this Plan, which provides as follows: likes of tipples
|
Development of forest research and education (direct expenditure by the Center) |
300 |
|
Development of matchwood plantations (so percent subsidy) |
100 |
|
Preservation of wildlife (grants to States and direct expenditure) |
110 |
|
Preservation of the use of secondary timbers by preservative treatment and seasoning (60 percent loans and 50 percent direct expenditure) |
100 |
|
Development of forest administration in the States (grants to State governments) |
100 |
|
Development of modern techniques of timber extraction and communications (long-term loans) |
400 |
|
Expansion of planting activities connected with valuable commercial timbers such as teak (long-term loans) |
200 |
|
Creation of Industrial plantation finch as wattle, blue gum (long-term loans) |
100 |
|
Acquisition of valuable private forests (long-term loans) |
200 |
|
Supply of fencing materials at concessional rates for rotational pastures and plantations (grants) |
50 |
|
Co-ordinating and technical service organization at the Center |
30 |
|
Total |
1,690 |
Note: 1 lakh = 100,000; 4.73 rupees = US $1.00.
The Board has also observed that certain projects of importance to the States, such as the development of the forest industries, including industries using forest accessory products, and the restoration of degraded forests, also deserve to be included in the Plan.
Among other important recommendations made by the Board are those which have been formulated in conformity with the recommendations of the Fourth World Forestry Congress, such as:
The Central Soil Conservation Board be requested to consider the possibility of setting up a Research Station to study the problem of raising shelterbelts in Rameswaran Island and similar areas.The supply of plantation stock to private owners of forest should be at cost price, but technical advice should be free.
A special study of forest grazing in the country should be carried out by the Center.
State working plans should pay special attention to the management of wildlife.
States should undertake special legislation to prevent the destruction of trees, especially in hill stations and other hilly areas outside forests as well as in urban areas.
Among the other important recommendations of the Central Board is that which aims to give to a Central Forestry Commission the task of examining important management plans drawn up in the States.
Iraq
· The FAO forestry adviser, G. W. Chapman, reports that Tree Festival celebrations were held in all but two of the provinces of Iraq during last March. In some of the forested northern liwas celebrations were not restricted only to a show at the capital town of the liwa but also in sub-district centers. In Baghdad, the King, accompanied by all the Ministers of the Cabinet, attended the celebration. Satisfactory publicity was achieved in the local press and radio broadcasting services.
Tree-planting activities connected with the Festival mostly took the form of roadside avenues. The Festival seems to have gone off most satisfactorily and is serving its purpose in stirring public interest in forestry and tree planting in a most effective manner.
Kenya
· The Government has decided to settle nearly 7,000 African families in the territory's forests during the next three years. A large number of those families will be Kikuyu.
There is some doubt in the public mind because many Kikuyu forest squatters employed by the forest department before the emergency were associated with the development of the Mau Mau organization and, not unreasonably, it is believed that not all the Kikuyu who will be allowed to return to the forest can be guaranteed to resist renewed threats or temptations.
The Government is taking a carefully calculated risk. Whereas previously these employees of the forest department were widely scattered and lived on land allocated for the cultivation of maize and other food crops, they will now live in villages under close control. No village will have more than 110 families and each village will be under the supervision of a European forester.
A pilot scheme has already been started. The objectives are first an increase in forest development, particularly the replacement of large area of natural forest by exotic softwoods, and secondly to relieve overcrowding in the Kikuyu tribal reserve while also helping some 30,000 men, women and children to become useful and self-respecting members of society. Employment as forest department squatters has always been popular with the Kikuyu, who appreciate the opportunity of cultivating virgin land. The villages will have welfare and social service amenities.
Philippines
· An FAO officer working at the new Forest Products Laboratory at Laguna writes of progress being made there.
Research work in timber testing is being continued according to the pattern established in previous months, and will continue in the same fashion for several months to come. The personnel has been given instructions and technical assistance in each phase of the work from establishing plans for correct procedure to making the final report which records the results and conclusions of the research. Projects include:
1. Evaluation of large leaf mahogany. The tests and report on this species in the green condition have been completed. The specimens that are to be tested at 12 percent moisture content are being conditioned in a chamber built for that purpose. The evaluation of strength at this moisture content and the report of the values can be readily incorporated later in the report on green strength.2. Evaluation of species for tool handles. Material has been secured for standard strength studies.
3. Evaluation of strength of structural timbers. Several thousand tests of green material have been made since 1 October 1955 on specimens representing many species from the Laguna area. The results of computations are being tabulated and are available for inspection and review.
4. Gravity survey. A report on the specific gravity ranges of 32 species from 10 major regions has been written and reviewed. This report summarized available information on the variation in gravity values for these species. The report indicates, contrary to general opinion, that in the majority of eases, the average density of a species in one region is not significantly different from that in another region when compared at the 5 percent moisture content level. This feet should be of great help in future sampling for extreme and representative qualities of species.
Thailand
· In connection with the first session of the Teak Subcommission of the Asia and Pacific Forestry Commission (APFC), on 11 February the delegates were taken out to visit the teak sawmills of the Forest Industry Organization and the East Asiatic Company at Bangkok. This provided the occasion for a river trip to see how the logs were rafted down the river from the forests to the mills.
On 12 February, the delegates left Bangkok by a chartered plane for Chiengmai but, due to bad weather conditions, the plane could not land and they had to return to Bangkok. The itinerary had to be changed and the delegates left by train on the following evening for Lampang and Chiengmai.
During the train journey the delegates had the opportunity of seeing some of the natural teak forests and some of the deciduous Dipterocarp forests worked under the coppice with standard system to supply fuels wood to the railways. On reaching Lampang on the morning of 14 February, the delegates were taken by ear to visit the natural teak forests at Mae Moh and Mae Huat and teak plantations at Mae Tark.
Passing through Mae Huat, the method of working these forests was explained. These forests are worked under the selection system and the delegates saw how teak trees over the prescribed girth limit were girdled in advance of felling. The delegates had also the opportunity of seeing elephants at work dragging logs from the forest.
At Mae Tark the plantations were created under the agri-silvicultural system (taungya). The growth of the experimental plantations in Imperata area was not very satisfactory as the seedlings had to face serious competition with Imperata grass in their early life. After completion of the inspection of the various activities in the Lampang area, the delegates left by jeep for Chiengmai, the second biggest city.
On 16 February, the delegates saw the experimental planting at Doi Sudep as well as the Huay Keo arboretum. In the latter area which is quite close to Chiengmai, the public is invited every Arbor Day to plant trees of economic value as well as ornamental plants. Besides, guests of the Royal Forest Department are also invited to plant some memorial trees. The delegates were all invited to plant each a memorial tree.
From the arboretum, which is situated at the foot of the hill, the delegates were taken to the Doi Sudep Experimental Station when they passed through some of the dry deciduous Dipterocarp forests before reaching the hill evergreen area. The experimental station is at an elevation of about 1,000 meters. At this station, important tree species of the north as well as the exotic temperate trees, fruit trees and ornamental plants are being experimented with. The work actually started in the year 1948 with a very limited fund and up to now about 40 species of temperate plants have been tried here, including the California Red Wood (Sequoia semipervirens) sapling, which was given as a souvenir to H.E. Field Marshal Pibul Songgram when he made a goodwill visit to the United States of America. In this experimental station a good success has been achieved with the plantation of Pinus merkusii - a two-needle pine generally found at lower elevation and P. khasya, a three-needle pine of higher elevation,
On 10 February, the delegates went out to see the teak plantations at Chieng Dow and also some protection works of watershed areas. During the trip the delegates also had the opportunity of comparing the teak forests of Chiengmai with similar forests seen on the previous day which were definitely of better quality. The poorer growth of teak at Chiengmai is attributed to poorer soil.
The delegates had further opportunity of seeing the experimental plots where exotic eucalypts are being tried with a view to finding some quick-growing species to replace the poor type of dry Dipterocarp forests. Preliminary indications are that Eucalyptus citriodora is likely to be suitable for afforestation in the poor dry sites whereas Eucalyptus deglupta is better suited for moister location, The introduction of the fast growing eucalypts has become necessary to meet the urgent problems of fuelwood supply to the tobacco curing stations located in outlying areas in the northern part of Thailand.
The trip took the delegates through various forest types, including Dipterocarp and hill evergreen forests. The latter at present is not worked to any great extent but serves the important protective function in the catchment areas of the rivers which are the only sources of water supply to the people living in the lower reaches.
Finally the delegates were led to Mae Na Oy teak plantation which was started in 1954 also under the taungya system. The growth so far appears to be quite favorable despite the fact that very few teak trees are found growing naturally in the surrounding forest.
Turkey
· A member of the FAO forestry mission forwards an official report on the Forest Research Institute of Turkey, which states that, at present, the Institute has two experimental forests. One is Büyükdüz Forest, which has the characteristic qualities of the coastal forests of the Black Sea, the richest forest district of Turkey, and the other is the experimental forest of Çamkoru, which serves as a bridge between the poorly forested steppe land and the forests of the Black Sea district.
The above forests are selected as experimental areas for conducting research work and are organized to serve as model forests of the Forest Service.
Büyükdüz is a mixed high forest consisting of fir, beech, pine and oak, located at a distance of 25 kilometers north of Karabük. Its altitude varies between 850 and 1,500 meters, The forest covers an area of 2,290 hectares; the growing stock per hectare is about 310 cubic meters.
A management plan of the forest is being drawn up and in connection with it, a general plan for 51 kilometers of roads, which should be built for protection and logging purposes, has been prepared and marked on the land. The project for a road of 0 kilometers has been completed and the work for actual road building started elsewhere. During 1955, stand improvement cuttings were done in compartments of this forest.
Çamkoru Forest, which is 24 kilometers northwest of Kizilcahamam, contains stands of Pinus nigra and Pinus silvestris. The altitude varies between 1,300-1,050 meters. The forest covers an area of 050 hectares and has a growing stock of about 100 cubic meters per hectare.
The general road plan of this forest has been completed and the construction of a main road started. The management plan of Çamkoru forest WAS drawn up according to a modern method in 1965 During 1954 and 1955, stand improvement cuttings were applied in two compartments of the forest.
On an experimental area in Bala, shelterbelts have been established in order to increase the agricultural production by avoiding the drying effect of hot summer winds on crops and soil.
The shelterbelt area lies east of Bala, at a distance of 22 kilometers and within the State Breeding Farm. The direction of shelterbelts is vertical to that of the predominant wind in this area. The total length of the shelterbelts is 5.0 kilometers and the width 30 meters; they cover an area of 220 hectares. The tree species suitable to the existing ecological conditions are used for the establishment of the shelter belts.
An experimental pasture has been created near Bolu where forest pastures cover a large area, in order to carry out research on grazing problems and to ease the burden of grazing off the forests, by improving the forest pastures. This pasture is situated in the locality of Aladag, on Seben Mountains, 27 kilometers north of Bolu. The experimental pasture, which covers an area of 43 hectares, is divided into 7 sections. It has an altitude of 1,350 meters. Three of these sections are assigned to different rotation grazing systems, another three sections to experiments on grazing intensity, and the remaining one section to pasture improvement,
Sweden
· The Society for Practical Forest Improvement at Uppsala is principally a consulting organization with the purpose of helping its members, on a scientific basis, with problems concerning reforestation. Co-operation with forestry institutes and agencies working in the same field, is pursued as far as possible.
In the period of 1956-60, the Society's work will mainly be:
1. Seed Supply: After completing the inventory regarding pine (Pinus silvestris) in parts of Sweden of immediate interest, the work with this species is to be carried out by propagating plus trees and establishing seed orchards. In total, 25 of these have been planned with an area of about 120 hectares (300 acres). In 20 years these are to yield seed for a plant production of about 120 million plants per annum. Pine grafts already planted in the orchards fill an area of about 30 hectares. Gradually, as the number of clones of each orchard become complete, the orchards will be definitely established. The intention is to get the four smallest orchards (1 to 2 hectares) ready in 1956 and all the orchards ready before the end of 1960. a view to their isolation, extensive protection plantings and the elimination of surrounding pines have been made.
The selection of plus trees of spruce (Picea abies) is being continued and seed orchards started. In the first orchard now planned for the middle of Sweden, spruces selected with an intention of gaining the highest possible pulp production are to be included. Increased attention is being devoted to birch, and plus trees of birch are propagated for seed production.
The studies concerning different methods for the treatment of graft trees in orchards in order to obtain an abundant and early seed harvest will be intensified.
2. Nurseries and Plant Care: Studies on nursery questions are to continue and practical information concerning the establishment and management of nurseries given by instruction and pamphlets. Investigations started in 1955, concerning the importance of temperature and moisture for germination and plant development (sowing season, irrigation, etc.) in the experimental nursery at Friggesund will be finished in 1956 and the results published.
A compilation of the comprehensive material of the Society with regard to the analyses of nursery soils will be done.
Data on the storing and care of plants are compiled and instructions regarding plants are distributed.
3. Reforestation: Developments in questions concerning methods and tools for forest regeneration are followed with a special consideration of biology. Detailed studies regarding the cause of plants dying back during the first year are being continued in co-operation with the silviculture staff of certain members.
Plantations with some North American and North Asiatic tree species have been laid out according to earlier plans.
4. Instruction and Extension: In its capacity as a service organization, the Society is to seek to bring out the more important results concerning reforestation, culled from literature and research institutes, and is also to inform members about practical experience. By 73 reports and personal contacts during demonstrations out-of-doors, it is possible for the Society to keep its members up-to-date with developments.
The comprehensive picture-archives of the Society are to be completed and the collection of instruction pictures (in color) in the matter of reforestation, especially concerning nursery management, plant care and planting methods, is at the disposition of members.
United Kingdom
· A note in Scottish Forestry, Vol. 10, No. 1, concerns the aftermath of the storm damage suffered in early 1953. With probably the greatest number of trees lying on the ground at one time that has ever occurred in Scotland, conditions existed for unprecedented insect damage, but luckily the subsequent wet summer ensured that the trees remained greener than was expected. The pine shoot beetle infestation was not as bad as was thought possible. The beetles have, however, increased quite considerably and have killed off many of the isolated trees which remained standing in the devastated areas, and also spread into adjoining woodlands. With the removal of the timber, their breeding ground has been reduced and their numbers should gradually come down to normal proportions before 1958 and so enable replanting with conifers to be undertaken.
The jungle of brushwood provided, and still provides, ideal cover for rabbits, but with the advent of myxomatosis the expected rise in the rabbit population did not take place; in fact, very few rabbits are now seen in woodland areas. The clearing of this lop and top is, however, important to enable any remaining rabbits to be killed. Serious fires, luckily, did not ravage any of the areas. Small areas were burned and some sawmills, but nothing to what could have happened.
Now that nearly all the blown timber has been removed, the second stage in clearing up is in full swing. Odd, scattered trees are being felled and preparations are going forward for the eventual restocking of the 25,000 acres (10,000 ha.) of woodland involved in this disaster. Opportunities have arisen for the possible restocking of these areas by natural regeneration now that rabbits have been considerably reduced, but a great deal of activity is foreshadowed for nurserymen in making good the damage.
The loss of both capital and income has been heavy on individuals but a National Fund made payments towards the cost of repairing and renovating roads, bridges, fences and buildings, and also in respect of blown timber. Payments at the rate of £40 per acre (£100 per ha.) for the first ten acres and £30 an acre (£75 per ha.) thereafter were made, up to a maximum of £5,000 to any one owner.
Although the volume affected amounted to less than 5 percent of the standing volume of timber in the United Kingdom, its loss is greater when considered in relation to the reserve of growing timber of its age and size.
· Proposals to create what were described as parish forests have been outlined by representatives of the Forestry Commission to members of the Royal Commission on Common Land.
This scheme, it was stated, was intended to satisfy objections by commoners and other local people, and from a wider public, to the acquisition for forestry purposes of land regarded as local property.
The plan was that where an owner of the soil and a majority of commoners signified agreement in principle to the use of a suitable common for afforestation, it would be open to the Minister of Agriculture, after consultation with local authorities and other interested bodies, to designate the ground as a parish forest. Compensation would be payable to those who exercised rights of common, and the freehold would be acquired by voluntary negotiation with money from the Forestry Fund.
The portions most suitable for forestry would then be vested in the local authority. Thereafter, the Forestry Commission would plant and maintain the forest on behalf of the local community, financing the work from the Forestry Fund. If necessary, an advisory committee of local people would be set up to ensure that local interests were taken into account so far as practicable.
Particular attention would be given to amenity, and the provision of access for the public to the maximum practicable extent, and of picnicking and camping sites where appropriate.
When net expenditure and interest on capital had been recovered, responsibility for the forest would be passed to the local authority for administration in accordance with plans approved by the Forestry Commission. The arrangement would be analogous to the management of a private woodland by its owner in accordance with a dedication agreement.
United States of America
· Forest Science has now entered its second year as a quarterly journal of research and technical developments. As the first new nation-wide American forestry journal since 1906, Forest Science is international in content and in appeal, being devoted to articles and reviews of primary interest to scientists, educators, and specialists. The need for the new enterprise has been demonstrated by its first year's history. Over 900 pre-appearance subscriptions received and more than 1,200 had subscribed by the end of 1955. Volume One contained 42 articles on 356 pages dealing with such topics concerned with the forest as species crossability in spruce, an economic approach to multiple-use, deer and cattle range relations, and the taxonomy and evolution of the sawflies.
· Genetical work in the Pacific northwest has led to the formulation of tentative guides for the selection of plus trees and superior stands in Douglas fir. The indications for plus trees are:
1. A plus tree should be one of the fastest growing trees in a given stand.2. The crown should be thrifty but not overly dense or limby in comparison with its neighbors It should have high vigor in the upper third of the crown and low vigor from there downward.
3. The plus tree's crown should be narrow. It should retain a wedge-shaped, well-pointed top, but from the upper third downward the outer edge of the crown should remain somewhat parallel to the stem.
4. The bole should be straight, have a high form factor, and be reasonably clear of branches between nodes and on the lower bole as trees approach maturity.
5. Limbs in the upper third of the crown should not make a sharper, upward angle with the stem than 60°/more nearly horizontal or drooping branches are better.
The indications for superior stands are:
1. It is better than surrounding stands or better than expected in a general locality or elevation.2. Better growth than expected is a first requirement.
3. The stand should contain an above-average number of high quality trees approaching the plus trees in desirable characteristics
Once selected, superior natural stands should be improved by removal of slow-growing, badly-formed and diseased trees which are bad pollen parents. Thinning and the mulching effect of the slash can be expected to stimulate grown growth. In thinning a superior stand, high quality trees should not be removed simply because they do not produce cones, since they may provide pollen. Additional measures such as pruning, topping, watering, fertilizing and insect and disease control should be undertaken in superior stands.
· American utility companies believe that they will be able to save themselves a great deal of money and trouble by adopting glass fiber poles for electric power cables and telephone lines.
One of the greatest enemies of the wooden pole is the woodpecker, which causes great damage. Wooden poles are also damaged by termites and by fungi.
Tests have shown that glass poles withstand temperatures ranging from well below zero to more than 100° F. in the sun. They weigh much less than wooden poles, and are therefore easy to instal and, from the esthetic point of view, they have the advantage that they can be made in any color.
· The Weyerhaeuser Timber Company, in an eight-page advertisement in the February issue of Reader's Digest, tells the full story of modern industrial forestry and what the forest industry is doing to grow and wisely use forest resources. The section, illustrated with striking, full-color pictures, is entitled "Promise of the Trees - The Story of Modern Forestry and Tree Farming in the Pacific Northwest." It presents a complete report to the American people on a subject of universal public importance - the conservation and management of privately-owned forestlands. Part of a continuing public information program, the message explains the company's policies and objectives and the progress made in the modern philosophy and science of forest management.
· A report entitled Wood Residue in North Carolina - Rata Material for Industry has been issued by the United States Forest Service cooperating with the North Carolina Department of Conservation and Development. The conclusions are summarized as follows:
1. Large permanent sawmills can profit by establishing a market for their wood residue with pulp mills in their area. Since the preference is for glean chips in dependable volume, they should determine the quantity of solid wood residue produced at their plant both in log and slab form; investigate the feasibility of installing log and slab barking equipment and chipping and screening equipment; and investigate the problem of transporting the chips by trailer or rail to the pulp mill. They might also look into the possibility of purchasing slabs from small sawmills within a reasonable radius of their plant.2. The concentration yards in North Carolina could benefit by making a survey of the small sawmills supplying them with lumber to determine the daily quantity of slabs that they could obtain from these sawmills and the price that they would have to pay for the slabs. They should further investigate the slab debarkers under development or on the market, chipping equipment available, and screening equipment available, with a view to collecting wood residue at their yard for conversion to pulp chips. The concentration yard owners, fortified with the figures on the amount of pulp chips they could produce per day, should also approach the pulp mills or synthetic board plants to develop a market for this material.
3. The veneer and plywood plants could investigate the feasibility of selling their cores for pulpwood if they are not already doing so, and might look to the synthetic board plants as a possible outlet for their scrap veneer.
4. It might be profitable for the furniture plants in the State to determine the amount of solid wood waste produced at their plants, as contrasted with fine wood waste, and thus be in a position to quote prices on this material to synthetic board plants or to concentration yards that might produce pulp chips for pulp mills capable of using hardwoods as well as pine. The furniture plants could also determine the volume of material that is of sufficient size to interest a manufacturer of smaller items. Perhaps listings of such material could be handled through a furniture association or through some advertising medium, so that this material would get back into commerce instead of to the boiler room.
5. Local communities that have several wood-using industries might arrange for detailed surveys of different types of wood residue available and present these data to the North Carolina Department of Conservation and Development to assist in helping new industries find suitable locations where ample wood residue of the right quality is available.
Persons interested in organizing companies for utilizing wood residue should obtain full information on the processes of interest. In addition to obtaining the technical information on a process, it will be necessary to make market surveys to determine the need for the proposed product.
Yemen
· The FAO Regional Forestry Officer for the Near East, participating in an official exploratory FAO Mission, writes that one of the most striking features of the landscape is the great number of trees which appear everywhere, except on the bare mountains above 2,600 meters in elevation, on the high plateau (from Naqil-Sumara to some 76 kilometers north of Sanaa) and in the coastal strip of Tihama.
A cross-section of the country from the sea to the high plateau shows first a strip of some 16 kilometers alongside the coast which is mostly sandy and bears no trees except a few doum (Hyphaene thebaica) and palm trees growing wild, and the bush Suaeda fruticosa.
In the lagoon of Lobeyia, Avicennia officinalis covers some 40 hectares, and is said to extend up to the Saudi Arabian border to the north, on perhaps 2,000 hectares. Near Hodeida, the same Avicennia is met, with another mangrove tree Brughiera gymnorhiza.
There are a few shifting sand dunes, but the economic potentially of that area is so small that it would not be worth undertaking their fixation at the moment.
A second parallel strip, varying in width from 10 to 30 kilometers has a better soil, is less open to the powerful sea wind, and bears large tracts of Salvadora persica and Cadaba rotundifolia. Tamarisk - mostly Tamarix articulata - appears in the wadi beds, and often reaches tree size, sometimes up to 10 m. high. The acacias also appear, first in the wadi beds, and then eastward on the flat land which is occasionally flooded.
In many places, Acacia flava (Sallam) appears almost as a weed invading cultivated or formerly cultivated fields, and seems afterwards very difficult to eradicate.
The next area is the foot of the mountains, where the valleys open widely in the Tehama. The cultivated fields are very important, and trees of fairly good size exist either scattered or sometimes grouped in a true, close forest, as for example some 2,000 hectares in the Wadi Surdad valley; this stand is composed mostly of Dobera roxburghii, called locally Daber, with some Delonyx elata, Salvadora persica, and the poisonous tree Adenum obesum with beautiful flowers. Balanites aegyptiacum and species of Grewia, Leptodinia and Pyrotechnica, are also met sometimes.
Leaving the Tehama to climb towards the first plateau, the slopes of the mountains bear a real forest of Acacia, varying in size from a dwarf, twisted bush to a tree 6 or 7 meters high, according to the depth of the soil, the exposure of the slope, the gradient and the elevation. Acacias appear to be the most common tree in Yemen; it is so abundant in many places, such as the hills between Tais and Ibb, between Wadi Rima and Wadi Zebid, north and north-west of Saada up to the Saudi Arabian border, that the stands may truly be called open forest. From a quick aerial survey and from field trips, it is estimated that this open forest covers nearly one million hectares.
It was not possible to identify all the Acacia species but amongst them were Acacia nubica, A. hamulosa, A. verungera and A. spirocarpa on the low, hot slopes. The "thala," which is closely related to Acacia seyal, reaches an altitude of 2,600 meters. It is often carefully preserved on the cultivated terraces, where it replaces the "ilb," Zizyphus spina christi, above 1,600 meters of elevation.
The "ilb" is the second commonest tree. It grows either in thick groves on the wadi banks subject to floods or on the terraces. It is often pollarded to obtain the leaves as fodder for livestock and to use the twigs as fuelwood. Its wood is also used as timber. The "ilb" gives to the landscape around Tais, and Ibb, its peculiar aspect of a giant orchard.
One wonders why the peasants do not grow fruit trees (olive or others) rather than Zizyphus, on their cultivated terraces. One wonders also why the natural vegetation is so completely xerophytic, in spite of a total rainfall amounting to 600 millimeters at least. The explanation may be that the lack of rain during the winter and the early spring, combined with the winter cold, which has been called sometimes a physiological drought, results in a temporary excessive drought, which precludes many of the Mediterranean or temperate plants and fruit trees from surviving.
Many thorny or xerophytic shrubs are mixed with the acacias on the slopes; in the valleys, the vegetation is often luxurious and dense and includes many Grewia, Maerua, Commiphora, Dodonea viscosa, and a great variety of Ficus: F. salicifolia, F. morifolia, F. vasta, etc.
Cordia myxa, grown as a shade tree on the coffee plantations, deserves special mention because of the excellent quality of its wood, used as building timber and for furniture making. Its planting should be developed and encouraged.
A few carobs (Ceratonia siliqua) are grown on the terraces of the Jebel Saber, near Tais, and in the Wadi Rima valley. Tamarindus indica grows well, and its fruits and timber are appreciated.
A notable feature of this part of the country is the extensive development of the euphorbs, mostly Euphorbia amak, which invades formerly cultivated fields and the degraded forest. The plant is totally useless, and the reclamation of such land for afforestation might be worth consideration.
When one reaches the high plateau, the almost complete disappearance of trees is striking: there are only some tamarisk (perhaps T. orientalis and T. articulata) a few acacia and zizyphus in the wadi beds, or along the irrigation channels.
In summary, there are a great variety of tree species in Yemen, the more important being the many acacias, giving firewood and charcoal, the multi-purpose Zizyphus spina christi, and the timber-producing Cordia myxa.
