M. A. HUBERMAN, Forestry and Forest Products Division, FAO
Throughout wide areas of the world, bamboos serve a multitude of purposes. Rural housing largely depends on them. Pulp and paper manufacture from bamboos is expanding. A monograph on bamboos is in preparation by FAO, but this article is a modified extract from the general volume entitled Tropical Silviculture recently published by the Organization. It deals summarily with the occurrence of bamboos; physical factors of climate and soil, silvical factors, growth habits, and silvicultural practices, as developed largely in Asia and to a lesser extent in Latin America and Africa.
Bamboo is one of the gregarious associations which occur in moist deciduous and dry deciduous forest, as well as in wet evergreen forest. To consider its silvicultural treatment only as an understory in these forests would hardly do justice to a family which is not only widespread throughout the tropical and subtropical (and even temperate) parts of the world but which has such tremendous importance in the everyday life of so many millions of people. In many parts of the tropics and particularly in Asia, bamboo is considered, next to rice, as the staff of life. To list its almost infinite uses would be to give a catalogue of practically every human need, even food in the form of fresh or preserved young shoots. It is used in the construction of houses, bridges, furniture, fishing poles, water pipes, weapons, bags, baskets, cloth, reinforcement of concrete, and paper manufacture.
All the continents except Europe have native bamboos. The 60 genera of Bambuseae, estimated to comprise more than 500 species, belong to the same family, Graminae, as corn, wheat, oats, barley and other grasses. They are woody perennials varying in height from 6 inches (15 centimeters) to over 100 feet (30 meters) at maturity. They occur principally in the tropics and in mild climates, although some species occur naturally in China, Japan, Chile, and in the United States, under temperate conditions. The genus Bambusa has the largest number of species, most of which are native to Africa, China, India and Japan.
Good (1953) notes that: "Unless the somewhat doubtful American species are correctly associated with the Asiatic species of Bambusa, only the more or less pantropical genus Arundinaria is found in both the Old and New Worlds. Oxytenanthera occurs in Africa and Asia; Schizostachyum in Madagascar, Asia and some of the Pacific islands including Hawaii; and Cephalostachyum and Ochlandra both in Madagascar and Asia. No other genus occurs in more than one sector of the tropics and some are quite narrowly distributed. It has been calculated that 90 percent or more of the 500 species are either Asiatic or American, the former being much more numerous than the latter. The representation of the bamboos in tropical Africa is remarkably small and (this is) one of their most striking features, consisting of only about 8 genera and 14 species, which is much less even than that of Madagascar, where there are 9 genera and perhaps 30 species."
Bamboos are an important component of wet evergreen, moist deciduous and dry deciduous forests in the tropical parts of southeastern Asia, principally in the Andamans, in Burma, Cambodia, Ceylon, India, Indonesia, Laos, Malaya, New Guinea, Pakistan, Philippines, Thailand and Viet-Nam. Genera found in these countries include Arundinaria, Bambusa, Thyrsostachys, Gigantochloa, Oxytenanthera, Dendrocalamus, Cephalostachyum and Melocanna. At higher altitudes and in temperate climates in Asia, as in Bhutan, China, Japan and Nepal, many of these genera are represented by different species, and other genera such as Phyllostachys and Sasa are common in China and Japan. In this connection, it is interesting to note that pure bamboo forests are common on slopes where shifting cultivation has been carried on in Burma, East Pakistan and other parts of Asia. In tropical parts of Africa, two indigenous bamboos occur, Oxytenanthera abyssinica in dry deciduous formations, and Arundinaria alpina in the humid highlands of the equatorial zone.
In Latin America, the genus Guadua is most important, G. angustifolia in Colombia and Ecuador, G. amplexifolia from Venezuela north to Nicaragua and Honduras, G. inermis in Mexico and G. superba in Brazil. The Guadua species are considered as indicators of good land for conversion into banana plantations. At the higher altitudes and in temperate climates of Latin America, the genus Chusquea is of consequence. Two species, Arundinaria gigantea and A. tecta, are the only native bamboos in the United States of America (McClure 1952a).
The cultivation of bamboos has meant the introduction of many exotic species in numerous countries. Thus, for example, in Argentina, Phyllostachys aurea, P. bambusoides, P. nigra, Bambusa tuldoides and B. vulgaris have assumed economic importance, and a number of others are used as ornamentals. B. vulgaris is the species most widely cultivated in the tropics of the Western Hemisphere, and has even replaced the native Guadua species, as in Guatemala and Nicaragua. This Bambusa has become established in Jamaica as a result of sprouting from stakes used in shifting cultivation of yams and other crops on steep hillsides. It is also common in Puerto Rico. B. tuldoides was introduced in Brazil from China over 100 years ago, often as hedges and farm boundary markers. Similarly, Phyllostachys aurea was brought into many parts of Latin America from China, and is probably the most common exotic bamboo next to Bambusa vulgaris. In China and Japan, many of the native species are also cultivated successfully.
Climate
The majority of bamboos thrive at temperature ranges of 48°F. to 97°F. (8.8° C. to 36° C.). Some species, however, grow at high altitudes, as in the case of some Arundinaria species up to 10,000 feet (3,050 meters) in India and up to 12,000 feet (3,650 meters) in Latin America, or in regions where frosts and snow are common, as Chusquea in Chile. Rainfall is an important factor, and 40 inches (1,020 millimeters) seems to mark the minimum annual precipitation required. The upper limit is not known but bamboos are found in zones with over 250 inches (6,350 millimeters).
The most common range is 50 to 160 inches (1,270 to 4,050 millimeters) per year. Relative humidity is correspondingly high and ranges from 80 percent upward. The distribution of the rainfall in Asia is affected by the southwest and northeast monsoons, which are often accompanied by strong winds but these do not seem to act as limiting factors to occurrence or growth.
Soil
Most bamboos are found on sandy loam to loamy clay soils, derived from river alluvium or frequently from the underlying rock. Yellow, brownish yellow, or light reddish yellow are the soil colors most frequently encountered. Humus may produce a bluish color. Subsoils vary from light red to yellow to bluish gray, and in some areas contain manganiferous iron and ferruginous concretions. Usually bamboo prefers well-drained soils but it is also found on swampy or wet stream beds. No bamboo is reported on saline soils. Individual species have well-defined habitats and for this reason may be taken as indicators of different forest types. For example, Bambusa polymorpha in Burma requires a moist, fertile, well-drained soil characteristic of the moist upper mixed deciduous forest. Dendrocalamus strictus, on the other hand, is associated with the drier forest types; and Cephalostachyum pergracile is intermediate between the drier and moister sites. Bambusa tulda occurs on stream bed alluvial flats; Oxytenanthera albociliata on low plateaus or hills on sandy or lateritic soils; Dendrocalamus longispathus on edges of damp ravines; and Teinostachyum helferi in the dampest valleys in evergreen forests. Under Indian conditions (Deogun, 1936; Sen Glupta, 1952), Dendrocalamus strictus does well in open, mixed deciduous forest or in open areas on stony hillside soils, and extends into drier conditions than any other bamboo. Bambusa arundinacea occurs on rich moist soil such as alluvial stretches along streams.
FIGURE 1. - A clump of Cephalostachyum pergracile tinwa bamboos in flower.
Courtesy, Insein Division, Burma
Composition
Pure bamboo forests are found singly or in compact or open clumps, but usually bamboo forms the understory of the evergreen, semi-evergreen, moist deciduous and dry deciduous forests of tropical areas. In most cases this understory consists of a single bamboo species and only rarely are more than one species found together. In the wet evergreen forests of Dipterocarpus spp., Calophyllum sp. and Artocarpus sp. in the Andamans, one finds the bamboo Dinochloa andamanica. Under oak, deodar, spruce and silver fir in northern India, Arundinaria is most frequent, whereas under the dry deciduous type, Dendrocalamus strictus is most common.
DESCRIPTION OF IMPORTANT BAMBOO SPECIES
|
Species |
Character |
Average height |
Internodes |
Diameter |
Wall thickness |
Culm sheath dimensions |
Remarks |
|
in feet |
inches |
|
|||||
|
Bambusa arundinacea |
Densely tufted, thorny |
80-100 |
12-18 |
6-7 |
Cavity 1/3 of culm |
12-15 |
Soft, wooded; branches from base |
|
B. polymorpha |
Congested clumps |
50-90 |
15-24 |
3-6 |
Thick |
6-7 |
Sheaths thick |
|
B. tulda |
Tufted |
20-30 |
12-24 |
2-4 |
0.3-0.5 |
6-9 |
Aerial roots first 9-10 feet (3m.) |
|
Dendrocalamus hamiltonii |
Clumps, dense thickets |
so |
12-20 |
4-5 |
0.3-0.5 |
- |
Sheaths stiff, persistent |
|
D. longispathus |
Tufted |
60 |
18-30 |
3-5 |
0.3 |
- |
Branches only on upper part; long fragile sheaths |
|
D. strictus |
Congested clumps |
20-50 |
12-18 |
1-3 |
Thick |
- |
Sheaths variable |
|
Melocanna bambusoides |
Singly at 2-3 ft. (1 m.) intervals |
40-70 |
10-22 |
1-3 |
Thin |
5-7 |
Lower 2/3 free of branches. Sheaths persistent |
|
Ochlandra travancorica |
Tufted, reed-like, dense thickets |
6-20 |
24-60 |
1-2 |
Thin |
- |
- |
|
Oxytenanthera nigrociliata |
Densely tufted |
30-50 |
18-30 |
2-4 |
- |
6-16 |
Dense black hair |
|
Teinostachyum dulloa |
Open clumps |
30-70 |
16-40 |
2-4 |
Thin |
- |
- |
Typical of the evergreen, semievergreen and moist deciduous forests of East Pakistan are such bamboo species as Melocanna bambusoides, Bambusa tulda, B. teres, B. vulgaris, Teinostachyum dulloa, Oxytenanthera nigrociliata, O. auriculata, Dendrocalamus hamiltonii, D. longispathus and Melocalamus compactiflorus. Associated non-bamboo species in these forests are Phyllanthus emblica, Litsea polyantha, Holarrhaena antidysenterica, Pterospermum tetragenum, P. acerifolium, Grewia spp., Saraca indica, Vitex spp., and Ficus spp. Associated with the bamboo Melocalamus compactiflorus is an important climber, Spatholobus roxburghi (Ahmed, 1954). Similar information as to vegetation associated with bamboo species needs to be developed for other tropical areas.
Succession
Bamboos are ready colonizers and when not wanted are difficult to eradicate. In many parts of India Dendrocalamus strictus is reported to invade open soil areas, and Oxytenanthera sp. and Melocalamus compactiflorus are stated to persist in the wet evergreen forest, developing to the climax stage. On the other hand, Melocanna bambusoides, which is typical of the moist deciduous forest, is indicated as not progressing to the climatic climax. Following flowering and seeding, the culms of most species wither and die and the stand may regenerate from seedlings which germinate in the succeeding rainy season, or sometimes from new culms sprouting from underground rhizomes.
Following disturbances such as burning or extensive clear-cutting, bamboo regenerates readily by producing new culms from the perennial subsurface rhizomes. Melocanna bambusoides, for example, invades clearings where shifting cultivation is practiced, spreads rapidly, thanks to its vigorous rhizome growth, and discourages or suppresses other species of bamboo as well as true tree species. To obtain natural regeneration of timber species it is necessary to cut the bamboos repeatedly. Such cutting or maintenance of complete overhead canopy, particularly on unfavorable soils, causes the bamboo to deteriorate or to be eliminated altogether. More recently, chemical sprays have been experimented with to control the bamboo under such conditions.
Seed production and establishment
For the most part, bamboos flower gregariously but sporadic flowering in patches is common, and annual flowering is known to occur in Arundinaria wightiana, Bambusa liniata, Ochlandra rheedii, and in the species of the Western Hemisphere. Among the species which flower sporadically are Dendrocalamus strictus, D. hamiltonii, D. longispathus, D. giganteus, Bambusa tulda, Oxytenanthera nigrociliata, O. albociliata, Arundinaria falcata and Cephalostachyum pergracile. The ability to predict the year in which flowering will take place would be very useful; but studies in Japan have failed to show any relation between flowering time and age, size of clump, thickness of stem, soil fertility or moisture, exposure to sun, climatic factors, or locality differences. In some species it is reported that plants of different ages may flower at the same time.
In India, the failure to produce new culms one year is held to be a reliable sign of prospective flowering the subsequent year. This has not been shown to be universally true, although observations on clump-forming species, as well as on the single-stem Melocanna bambusoides in India, point in this direction. Physiological disturbances caused by injury, cutting, or prolonged hot, dry weather have been mentioned as possible stimulants to flowering but there seem to be numerous exceptions. Obviously more study is needed on this question.
In the gregariously flowering species the interval from germination of the seed to the next general flowering establishes the life cycle, which seems to be fairly constant. Life cycles have been determined for certain species as follows:
|
|
Years |
|
Arundinaria falcata |
28-30 |
|
Bambusa arundinacea |
32 |
|
Chusquea abietifolia |
32 |
|
Dendrocalamus strictus |
32 |
|
Bambusa tulda |
35-40 |
|
Melocanna bambusoides |
45 |
|
Bambusa polymorpha |
60 |
|
Phyllostachys nigra |
60 |
According to Troup (1921), gregarious flowering takes place in three stages: preliminary sporadic flowering, gregarious flowering, and final sporadic flowering, with varying intervals between these stages. It may occur over small areas or over hundreds of square miles. It has been observed to begin in one locality and to spread in a definite direction, requiring several years to extend over the entire flowering area. This is very important in connection with teak regeneration. When the flowering occurs, the culms retain their loaves in the early stage, usually dropping them as flowering proceeds. Flowering occurs usually in December and January.
Fruits ripen from February to April, or in some localities to as late as June. Seeds germinate quickly, but can be preserved for three months to two years.
Stand development
The bamboos are of two classes: the more important clump-forming bamboos, with peripheral extension from rhizomes (caespitose), and bamboos with single culms scattered over a network of rhizomes (dumetose). The first class, represented by the genera Bambusa, Dendrocalamus and Guadua, are generally tropical and cannot endure freezing temperatures. The second class, represented by the genera Arundinaria, Phyllostachys and Melocanna, are usually found in temperate regions. Intermediate between the clump-forming and single-culm classes is the high altitude genus Chusquea, some species of which form clumps while others produce single stems.
Growth habits of clump-forming bamboos are well illustrated by the various species of Dendrocalamus (Deogun, 1936; Sen Gupta, 1954). Dendrocalamus species, after germination, produce a grass-like seedling the first year. The plumule, which appears as a conical bud covered by sheathing scaly leaves, develops rapidly into a thin wiry stem bearing single leaves, alternate at the nodes, the leaf bases covering the stem. Fibrous roots form at the base of the young shoot and successive pointed buds appear on the rhizome. These buds form short rhizomes which curve upward to produce an aerial shoot. This process of rhizome and shoot production continues for several years, and as the previous year's shoots die down, new rhizomes grow deeper and new shoots appear each succeeding year. The clump is formed by these short rhizomes, sometimes as congested, sometimes as open clumps, depending on the species. D. strictus requires 12 to 13 years under natural forest conditions, or six years in artificially established stands, to form a mature clump.
Growth habits of the non-clump-forming group are shown by various species of Melocanna, which produce laterally spreading rhizomes which may run to considerable distances and send out single culms at varying intervals. Seedlings grow vigorously and form strong culms, becoming quite high in one season and reaching merchantable condition in four to five years. Culm development, according to some observers, depends on average thermal conditions, and even hourly growth rate is reported to vary with temperature fluctuations.
Volume and yield
In natural bamboo stands sales are made on the basis of area or number of culms. Volume and yield data are very meager but figures, which are not entirely satisfactory, have been derived from extraction records in annual reports of forest divisions in India, or from compartment enumerations showing numbers of culms per acre. In Chittagong Hills Tracts in East Bengal, figures of 1,200 to 3,600 culms per acre (3,000 to 9,000 per hectare), and in another stand an average of 6,000 culms per acre (15,000 per hectare), have been reported on a three-year rotation (Ahmed, 1954). Experimental weight determinations of Melocanna bambusoides in this region indicate that 1,000 culms (entire) weighed 4.4 tons (4.5 metric tons) green or 2.5 tons (2.6 metric tons) air dry. This would mean air-dry weights of 3 to 9 tons (3 to 9.5 metric tons) and 15 tons per acre (38 metric tons per hectare) for the three year rotation, on the basis of the above-mentioned counts.
In India, weighing of dry internodes for paper production purposes gave figures of 4.6 tons (4.7 metric tons) of Bambusa polymorpha and 4.1 tons (4.2 metric tons) for Cephalostachyum pergracile in the same area, or an average of 8.7 tons per average acre (22 metric tons per hectare), presumably for a three-year rotation. In Burma, in a similar type of forest, a total figure of 19.5 tons (20 metric tons) is reported for these two species. Melocanna bambusoides is reported to have yielded 8.3 tons of dry culms per acre (21 metric tons per hectare). Bambusa arundinacea yields varied greatly, from 1 to 14.5 tons of dry internodes per acre (2.5 to 36 metric tons per hectare), but the average of a large area is said to approach the higher figure. Very striking data are available for yields from plantations in southern Louisiana and Savannah, Georgia, in the United States (Sineath, 1953).
Pests and diseases
Bamboo stands present few serious insect or disease problems. Attacks have been noted of Estigmena sinensis, and Cyrtotrachelus longipes on the top bud, locusts, termites, and aphids; the bamboo scales, Asterolecarnium miliaris and A. bambusae; Ochrophora montana on seeds; as well as the fungus, Loculistroma bambusae. Control of the latter consists of removal and burning of affected culms, and in some cases coccinellid beetle have been successfully established as predators on the scales. Much more serious is the powder post beetle, four species of which (Dinoderus brevis, D. minutes, D. ocellaris and D. pilifrons) can render bamboo culms useless after felling. A cerambycid, Stromatum barbatum, has also been reported. Control of these beetles is achieved by confining cutting to the cold season when beetles are least active, and keeping the cut culms in water to leach out the disaccharides on which the insect feeds. Direct control measures include external application of DDT in diesel oil, kerosene (5 percent), or water suspension; dinitro-o-cyclo-hexylphenol; and impregnation by resin, creosote, Wolman salts, borax, inorganic salt solutions, or Rangoon oil. Heating in a kiln is also reported to be effective.
Courtesy, Forest Research Institute, Dehra Dun
Fast-growing vines can smother young bamboo seedlings and transplants. Successful control has been secured by spraying these climbers with a 2,4-D solution.
Fire and grazing have been mentioned as injurious agents. Although bamboo is able to recover from burning and some grazing, young seedlings and sprouts in newly regenerated areas need to be-protected against both. If cutting operations leave too few culms standing, strong winds may cause serious blowdowns and breakage. Such operations should only be conducted in areas subject to wind storms if one is prepared to risk this possibility.
Rats, porcupines, squirrels, hare, deer and monkeys are known to damage young bamboo by gnawing rhizomes or eating tender shoots or seeds. Goats and cattle, besides eating juvenile foliage, also cause damage by trampling the rhizomes; monkeys can break young culms by jumping, and elephants can damage entire clumps in feeding or by trampling.
Silvicultural practice with bamboos, largely restricted to the Asian area, is relatively simple and closely adapted to the striking generic and silvical features just described. In general, the mature culms are cut and regeneration obtained from new culms produced annually from underground rhizomes, and this relatively simple practice is followed everywhere regardless of the species or type of forest. Only after gregarious flowering, usually at long intervals and after which the culms of most species wither and die, is regeneration ordinarily obtained from seed.
Both clear-cutting and selection systems are commonly employed in bamboo forests. Practice varies somewhat according to the growth habits of the two great classes of bamboos previously described, i.e., the more important class with peripheral extension from rhizomes, thus clump-forming; and a second class, less important, which produces single culms scattered over a network of rhizomes. With clump-forming bamboos, the clump itself is the working unit to which thinning, improvement or harvest cuttings are applied. In the non-clump-forming group the regeneration area is similar to that of an ordinary forest, except perhaps on a smaller scale, with single scattered culms forming the working stock over any suitable cutting area.
In both classes, under the selection system, the mature culms are cut on a short felling cycle, usually three to five years. The best age to cut the culms for marketing varies with species but ordinarily ranges from two to six years. Generally, the larger species require a longer time to reach harvesting age, though the time required depends in large part on the condition of the rhizomes. Overmature culms start to decay, reducing their quality and market value of the stems, and the usual silvicultural precautions must be taken to preserve maximum vigor and productivity of rhizomes and culms, such as by cutting out overmature, defective and unmerchantable culms and securing even distribution of culms within each unit stand or clump.
Under the selective system most frequently applied to the clump-forming bamboos, the clump itself forms a small sample in which thinnings, improvement cuttings and harvest cuttings are conducted, congestion avoided and even distribution of the culms secured. Under this system, newly propagated bamboo, whether from seed, rhizome or culm-cutting, takes from four to seven years to reach a normal clump of full-sized culms capable of normal annual production of new shoots, though generally, seedlings take a little longer to reach this stage. Cutting cycles of two to five years are preferred - but three- or four-year cycles seem to be the optimum for maximum vigor and productivity of clumps. Selective cutting should be conducted so as to cause a minimum of disturbance, and it is essential to retain a portion of the old culms (that is, culms more than one year old) preferably, all second-year, in addition to the first-year, both for mechanical support of new shoots and to maintain the rhizomes in full vigor. Due consideration must be given to even spacing and the necessity to relieve congestion.
However, elaborate cutting rules may become necessary. Felling rules followed in Southeast Asia prohibit cutting of shoots of the last rains, removal of roots, or cutting culms at more than 1 foot (30 centimeters) from the ground, except where density of the clump makes this impracticable. Similar elaborate rules have been developed in India (Seth, 1954) for Dendrocalamus strictus and a few other species, involving time of fellings, height of culm cutting, number of culms to be cut, cleaning and improvement thinning. Supervision to assure compliance with the rules then becomes very important but is extremely difficult.
These disadvantages are overcome under the clear-cutting system with its simplicity and concentration of working, and suitability for mechanization; but such advantages are again offset by the need for a considerably longer cutting cycle (a clear-felled clump taking longer to mature into a full-sized production stage again) and perhaps greater liability of clumps to deterioration and mortality. The choice of a system is, therefore, a matter for decision by individual forest owners, though bamboo forests worked over a long period of years seem to indicate that area for area, selective cutting gives a somewhat greater yield than clear-cutting and is preferable.
In the case of noncaespitose bamboos, although clear-felling again would be most practical and is more frequently used, it seems desirable even under this practice to retain a few stems per acre, regularly spaced, so as to ensure maximum vigor and productivity of rhizomes.
Whatever system is practiced, the possibility of gregarious flowering taking place at a long but more or less regular interval of years over the entire bamboo forest, with all clumps eventually dying, must always be borne in mind. Following gregarious flowering, regeneration is ordinarily obtained from seed germination, which occurs at the start of the following rainy season. Clearing the area is the only suitable procedure.
Courtesy, Pyinmana Division, Burma
The ground should be bare and the area should be protected against fire and grazing. Seedlings usually carpet the ground, particularly where the mineral soil has been newly exposed. Generally speaking, with proper protection, the seedlings subsequently succeed in suppressing the regeneration of trees.
Cleaning operations relieve congestion in clumps and dense stands, promote regeneration and facilitate harvesting. Weeding is usually necessary only after seeding, to reduce competition for the seedlings from undesired tree species. Improvement cutting and thinning may be conducted to remove those mature culms which would interfere with natural bamboo regeneration. Pruning is practiced only with those species which produce thorny thickets. Although elaborate tending is seldom required, prescriptions for such work are included in many working plans in Indian forests. Here again, the ability to provide supervision of such work will govern their application.
In some areas, artificial regeneration is resorted to after clear-cutting. Direct seeding has been used successfully, by line sowing, both irrigated and non-irrigated. Propagation methods have been developed successfully in Asia and in tropical America (McClure, 1952).
The gregarious nature and vigorous growth of most bamboos require that they be considered as an important element in the silvicultural practice of the wet evergreen, the moist deciduous and dry deciduous forest. Where the true tree species of these forests are more important for commercial or protection purposes than the bamboo, measures of controlling the latter need to be developed and applied. But where the requirements for rapidly grown uniform raw materials are paramount, then management of natural bamboo stands, or even propagation and establishment of bamboo plantations, deserve serious consideration. In both cases, there is a need for concentrated research in many phases of bamboo silviculture and management. This is especially important in view of the rapidly increasing demand for bamboo for numerous uses, and particularly for pulp and paper, as well as for housing construction.
Research could well devote attention to the following problems. Flowering, seeding, sprouting, and growth habits are known for many species in many localities, but there is conflicting information in the literature which requires careful observation and study on a species and locality basis. Records of phenology and particularly of gregarious flowering should be collected and maintained. The species Dendrocalamus strictus appears to have been carefully studied, but few others are covered adequately. The annual production of new culms per clump as affected by age, treatment, and origin from seed or sprouting from rhizomes should be observed more carefully and systematically.
Experiments are needed on clear cutting and selective cutting, on rotation age, cutting cycles, and cutting intensities for the economically important species, similar to work done on D. strictus. This is particularly urgent for non-clump-forming species.
All aspects of artificial regeneration, especially optimum planting season, for various soil and climatic conditions should be investigated Propagation methods are well recorded, but need local trials to improve and standardize local practices. Field tests of results from introduction gardens would be very useful.
Protection measures are fairly well known, but treatments to prevent damage to cut culms, especially for pulp and paper purposes should be standardized.
Volume and yield data are urgently needed. A simple sampling procedure for determining such facts as age and number of clumps, culms per clump, and average weight, on an acre basis, would be desirable.
Improved forest management methods for bamboo would be greatly facilitated by such research.
AHMAD, M. S. Karanpur and Bindruban bamboo forests. Indian For. 66 (5), 1940. 273-284.
AHMAD, Y. S. Bamboo. Paper presented to the Fourth World Forestry Congress, Dehra Dun. Tropical Silviculture II, 1954. 283-286.
AHMED, J. Methods K. of increasing growth and obtaining natural regeneration of bamboo type in Asia Paper presented to the Fourth World Forestry Congress, Dehra Dun. Tropical Silviculture II, 1954. 287-297.
BALL, J. D. Bamboo: Its Cult and Culture. Elder and Co., San Francisco, 1945. 200 p.
BROWN, W. H. and FISCHER, A. F. Philippine Bamboos. Phil. Burl For. Bull. 15, 1918.
DEOGUN, P. N. The Silviculture and management of the Bamboo (Dendrocalamus strictus). Indian For. Rec., Silviculture 2 (4), 1938. 75-173.
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Annotated Bibliography on Bamboos. Prepared by For. Res. Inst., Dehra Dun., 377 titles with abstracts, 1954.
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Bamboo culture in the South Pacific. (See McClure, F.A.) Unasylva, Vol. 10, No. 3, 115-116, Rome, 1956.
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Bamboo. Paper presented to the Fourth World Forestry Congress, Dehra Dun, 1954 (See Ahmad, Y.S.) Tropical Silviculture II, 283-286, Rome, 1957.
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Methods of increasing growth and obtaining natural regeneration of bamboo type in Asia. Paper presented to the Fourth World Forestry Congress, Dehra Dun, 1954. (See Ahmed, K.J.) Tropical Silviculture II. 287-297, Rome, 1957.
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. The taxonomic conquest of the bamboos, with notes on their silvicultural status in the Americas. Paper presented to the Fourth World Forestry Congress, Dehra Dun, 1954. (See McClure, F.A.) Tropical Silviculture II. 304-308, Rome, 1957.
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Natural regeneration and treatment of bamboos. Paper presented to the Fourth World Forestry Congress, Dehra Dun, 1954. (See Seth, S.K.) Tropical Silviculture II. 298-303, Rome, 1957.
GALLOWAY, B. T. Bamboos: Their Culture and Use. Agric. Inform. Bull. U.S. Dept. Agric. 1329, Washington, D.C. 1925.
GARDENER, J. C. M. Insect Borers of Bamboos and their Control. Indian For. Bull. 125, 1945. 17 p.
GLENN, H. H. et al. Seasoning, Preservative Treatment, and Physical Property Studies of Bamboos. Engineering Exp. Sta. Clemson Agric. Coll., Clemson, South Carolina. Bull. 7, 1954. 47 p.
GOOD, R. The Geography of the Flowering Plants. (2nd edition). London, 1953, 452 p.
KADAMBI, K. and RAWAT, A. S. On the causes of congestion in Dendrocalamus strictus. Indian For. 75 (6), 1949. 198-312.
KRISHNASWAMY, V. S. Silviculture - natural regeneration including artificial supplementation - tropical. Paper presented to the Sixth British Commonwealth Forestry Conference, Canada, 1952. 10 p.
KRISHNASWAMY, V. S. Bamboos - their Silviculture and management. Indian For. 82 (6), 1956. 308-313.
McCLURE, F. A. Bamboos as a Source of Forage and Fodder for Livestock. USDA-OFAR, Washington, D.C., 1952a.
McCLURE, F. A. Bamboos in Latin America. Turrialba 2 (3), 1952b. 110-113.
McCLURE, F. A. Bamboos as a Building Material. USDA-OFAR, Washington, D.C., 1953. 52 p.
McCLURE, F. A. Bamboos as a Building Material The taxonomic conquest of the bamboos with notes on their silvicultural status in the Americas. Paper presented to the Fourth World Forestry Congress, Dehra Dun. Tropical Silviculture II, 1954. 304-308.
McCLURE, F. A. Pakistan J. For. (6) 1956. 182-186.
McCLURE, F. A. Bamboo culture in the South Pacific. Unasylva, 10, (3), 1956. 115.
OSMASTON, B. B. Rate of growth of bamboos. Indian For. 44 (2), 1918. 52-57.
PRASAD, J. Silviculture of 10 species of bamboo suitable for paper manufacture. Indian For. 74 (3), 1948. 122-130.
RAIZADA, M. B. and CHATTERJI, R. N. World distribution of bamboos. Indian For. 82 (5), 1956. 215-218.
SCAP. Production Consumption, and Stockpiles of Bamboo in Japan. GHQ Nat. Res. Sect. Rep. 27, Tokyo, 1946. 13 p.
SEN GUPTA, J. N. Cultivation of Bamboos in West Bengal. W. Bengal For. Bull. 1, 1952. 10 p.
SETH, S. K. Natural regeneration and management of bamboos. Paper presented to the Fourth World Forestry Congress, Dehra Dun. Tropical Silviculture II, 1954. 298-303.
SINEATH, H. H. et al. Industrial Raw Materials of Plant Origin, A Survey of Bamboos (Part V). Georgia Inst. Tech. Engineering Exp. Sta. Bull. 18, 1953. 230 p.
TROUP, R. S. The Silviculture of Indian Trees. Oxford. 1921. Three volumes, 1,195 p.
VERHOEF, L. Bamboe Cultuur op Java. Proef. voor het Bosch. 15, 1929.
WHITE, D. G. Bamboo Culture and Utilization in Puerto Rico. Circ. Fed. Exp. Sta., Puerto Rico 29, 1949.
WILDMAN, E. de, Les bambous en Afrique. Rev. gén. Colonie belge (Congo) 40, 1921. 1-30.
