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Multiple Uses of Forest Trees Many agricultural species are grown for single products and for specialized uses, but forest trees are often grown for more than just pulp or timber, and even those products have multiple end uses. Because genetic variability has been demonstrated in most of the growth, morphological, and anatomical properties of trees, the economic values for which trees are managed can depend on their genetic variability. It also seems clear that the wide range of management systems and intensities that have already been applied to trees and forests have some influence on their genetic variation. BENEFITS OF TREES AND FORESTS Forests and trees provide a variety of benefits to humans. Those benefits can be divided into two major categories: direct and indirect benefits (Burley, 1987~. Direct Benefits Direct benefits and uses include forest products of economic impor- tance, such as sawtimber and numerous other construction materials, fodder, and fuelwood. Trees have been used throughout the world for millennia, and today over one-half of the wood used each year is burned for heating and cooking. In some countries in Africa, for example, 70 percent or more of the total energy used is provided by wood (Table 2- 1~. 37

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~ / ~! Me County TABLE 2~1 Sham of Total Enemy U~ Domed by Wood, fled Cannes' beady lions - W-d S~ha~ of To~1 Envy U Mica Kenya ^ . Dugan Nigeria . ~ . Awns land ^ . .. Buying Asia China . . . ,. .~^~ 4..~,~ , .o~es~a Ne~1 ,. Stir America 8~azil ~ a. gosh ace Nicaragua ~~gua~y 71 82 92 93 96 >2 S3 50 94 an ~ lndude~ a~hcu~ltu=~1 Hastes and darn% in addition to Used and . ~ ~ charcoal. SOURC-E: S. Poster and L. Heirs. 1S8. Represent the Bash. ~o~d~tch Mar ax. Shin ton, D.C.: ~o3~d~atch ~I!ns~tc. Repdn~d Hitch permission. Cutrent gIo~1 flood p~~duc~on ap~p~ximates 1.5 billion amp annually Able 2^2), as recorded in nabona1 government statistics. but the use of add~itiona1 vast quantities of wood goes u~n~=co~rd^. Another Coup of Food uses comprises reconstituted and ~assemb~d wood, i.nclud~in~ . ~ veneers, chip boa fiberboard, pulp, and paper. Total ~o~1 trade in pair products approximates ~ Lion off imports and exports (food am A~d~ltu~e Orya~qiza~on !9~) lag JESUS O: pang plums prudes Lame to nations ~on- omies and individuals. This type of e=~lov~ent is often seasonal and . . ~ , , provides Oxfam income Then seasonal onion ~o!/kl~oads are low. The haresEng/ sailer and pro~ss~in~ off Ducts Am ages in co~mbi- nation glitch arming also reduce the asks associated With incomes based on one or To cash maps. The number of products provided by trees w~o~r~ld~ide is extensive. He mood, bag, leaves, 6), seeds, and Cots of ages geld gods fodder, shelter, medicine, afar/ resins, oils/ and numerous other l. ^ .....

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Multiple Uses of Forest Trees / 39 products used for subsistence and industrial purposes. In some countries the products from trees are important contributors to individual, village, and national economies (Myers, 1983a). Forest products can serve as feedstocks to support a wide range of local and commercial industries, drugs, food for human consumption, and fodder for animals (Panday, 1982; Parkash and Hocking, 1986~. In India, Myers (1988) estimates the amount of annual revenue derived from such minor forest products is $200 million. This equals or exceeds India's revenue from wood extracted from the forests. Management of forests for this variety of uses ranges from intensive cultivation on large industrial tracts, such as in the southeastern United States, to purely exploitative extraction with no plans for forest regen- eration. In some societies, nuts, leaves, bark, roots, latex, and various other parts of trees are collected as semidomesticated agronomic crops. In the western Amazon, for example, tapping rubber and collecting Brazil nuts are combined in forests, known as extractive reserves, that may provide income while conserving the tropical forest ecosystem (Cowell, 1990; Pearce, 1990~. TABLE 2-2 World Production of Industrial Roundwood, 1985a Share of Volume Total Country(million m3) (percent) United States347 23 Soviet Union275 18 Canada165 11 China/Taiwan93 6 Brazil58 4 Sweden49 3 Finland39 3 Japan33 2 Malaysia32 2 France29 2 All others383 26 World total1,503 100 a Industrial roundwood is defined as logs, pulp, and other raw materials used to manufacture wood products. SOURCE S. Postel and L. Heise. 1988. Reforesting the Earth. Worldwatch Paper 83. Washington, D.C.: Worldwatch Institute. Reprinted with permission.

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: :~: : : :~::: :::::~: ::::::::::~::~:~:::~::~. ::: .::~: A::. :~:~:~:~:~ :~aa~a~a~aaaa~a~aa~a~a~a. ~.aaa~aa / A Sharps Olin the cenb~lh~ ~ ad e Con of Nepai~ca~des Adder Cam woo ^ ad on a nearby hillside to ~ed~li~es~k. Fodder can be an impotent pan of~househo~ld income, butits overcol~lecdo~n in areas of high p~pJ~labon density can cause sedousda ~ guts nea~rby:~res~. Credit: Steve!n Ki~n~. ~lnd~ecibe~ne~Ctsof~esinclu!deenvi.ronmen~lpro~ctio~nand.a~=enilv (soc~T)va~lues.Tteesconidb~teto the s~sta~inabi~Ii~ty ofland prod~ctivii by co~nthbu ~ ~ to the for~natBon,structure, and fertility ofsoi~lin~man) Says Po!r exam pie, they form sy~nibi~o~tic relationships v~i~tb nutien~t- ibso~bt~g fungi off nitoogen~Fx~i~n.~ bacte-da and fungi, arid moderate grater Boat and loss v~hile-bindin~ soils to prevent eros~o-n Trees also contribute significantly to reducing greenhouse gases and associated ldbalte~m~perab~re rises by conve~rurg~:caYbo~n dioxide to carbohydrate through p~hotos~yntiesis and then locking it up v~-it~b.i.n their structures. l]>ein~direct costs ofign~ohn~g the protection p:rovidedio the ecosystem by healthy forests can be ve~y:bigh. Deforests don and poor cu.ltitatio~n Prances have been cited as mayor causes fo~rd~ra~mabc dsesin sediments in dversysfems around the Torrid (Poster, 19S9~. lncrea~sed sedimentation into reservoirs as a result of soil runoff is dramadcaIly reducing the lid span of several hydr~icctdc dams. in The Philippines, it is estimated that sedi~=entabon rates in two re~rvo:irs increased by moire than 1

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Multiple Uses of Forest Trees / 41 percent between 1967 and 1980. As a result, the life span of the Philippine Ambuklao Dam project has been cut in half. A similar process is occurring in Costa Rica, where siltation may significantly reduce the lifetime energy production of the Cachi hydroelectric project (Poster and Heise, 1988~. Forests are much more than an assemblage of woody trunks with leafy canopies. Trees determine the structure and organization of forest ecosystems, which provide habitat for a multitude of species of plants, animals, and microorganisms used directly and indirectly by humans. Species diversity itself may be considered an indirect product of forests, especially in the tropical moist forests, which contain at least one-half of all known plant and animal species (Food and Agriculture Organi- zation, 1985c). The amenity benefits of forests and trees include scenic beauty, the opportunity to view wildlife, and access to wilderness areas for study and recreation. It is widely accepted in developed countries that such amenity resources should be made available by the government for the benefit of the people, possibly with direct user fees as well as with indirect contributions through taxes. In developing countries, govern- ments are realizing, however, the importance of natural resources, particularly forests and wildlife, in attracting tourists and foreign exchange. Trees also serve as cultural and religious symbols. One example of this is the sacred forests and tree species that are found in India and other countries in Asia. IAND USE SYSTEMS INVOLVING TREES Land use systems form part of the full spectrum of uses of forest trees. A variety of land use systems incorporate either deliberately planted or naturally occurring trees. These systems can be divided into three major types: natural vegetation management, agroforestry, and industrial plantation forestry, each of which produces major benefits. The first type of system does not usually involve selection of trees with a specific genetic composition (genotypes) or any other direct manage- ment of genetic variability, whereas the second and third types use mixtures of genotypic selection (and occasionally direct breeding) and indirect genetic management. Natural Vegetation Management Conservation, protection, or management of naturally occurring for- ests to preserve their biotic integrity is natural vegetation management.

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~ / Oaf TO Tags ire a soup of ~01 ~iou~ou~t the Gould!. Kilns near l~lhe~s~,~hia, By, ~ ~. Credit: Douglas Lye. This can include selectee h.arest of forest products. Con side able research as been p~de#aken on Me s~sta~ipabIe m.~page~nt of Topic moist Rests Oberon and Vi~n~nt' 198~ byatt~Sm:i~t~, 1987~/ and it is tonse~~bon of these forests that is regiving the roost Benson in the media. Be genes i~pl~i^~tions of Such natural vegetation ~a~gement systems remain unexplored, cart the population sizes and the stare of genetic On maintained byth~ose~systems ~ouldun~doubtedl~y Aged ~evbl~i? of these ^~sys~s.Rea ~ ~ bad Tendon ha been {yen to the con~se ~ tion of Bees and shrubs in doer zones, although they maybe the sole sou~=eofs0=ep~lint ma~r~Is,especiall~v Or ED and fodder. OPen' tag, the day zones contagion tree species thy could have goat potential as exotic (~non~naJ~e) toes for other argons. A range of And management systems, including Oral development Best, aDey fling, am s~vipastoral system am often c~lec~vely termed agro~rest~. Trees, crops/ and domestic animals are mixed

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Multiple Uses of Forest Trees / 43 simultaneously or sequentially in such systems to obtain increased and sustained multiple benefits from limited land resources. In rural devel- opment forestry, planted trees are used for the benefit of rural com- munities or individual farmers. Such systems include the small plan- tations of community and farm woodlots and the establishment of trees in farmland for shade, shelter, fuelwood, soil improvement, or other purposes. The selection of source populations and species for these systems is just beginning. One of the most widely researched agroforestry systems is alley farming. This is a term for a form of land use in which one or more rows of trees are planted alternately with several rows of agricultural crop plants. The trees in this system are hedged (cut back frequently) and contribute decomposing leaves (mulch). This practice increases soil fertility and provides fuelwood as well as other benefits. Despite considerable research, however, adoption rates for alley farming remain low. Silvipastoral systems incorporate tree and shrub management and animal husbandry. The trees are used for fodder production, shade, and pasture improvement. The intensity of such operations varies from extensive range management in dry zones to intensive trees-over-pasture systems in areas of higher rainfall. The trees may be planted or occur naturally. Research on agroforestry systems is increasing and often benefits from a multidisciplinary approach. Much of the work is being conducted as part of the research program of the International Council for Research in Agroforestry. Related research and development work on multipur- pose trees and agroforestry systems in India and in southwest and southeast Asia is being conducted as part of the Forestry/Fuelwood Research Education and Development project coordinated by the For- estry Research Institute of Malaysia (Plucknett et al., 1990~. Industrial Plantation Forestry Industrial plantation forestry is practiced on large areas that are established and managed intensively, often with exotic species, for the production of timber to supply sawmills, pulpmills, veneer factories, chipboard plants, and so on. In developing countries, the plantations are usually owned and managed by state enterprises, although com- munity, company, and private ownerships of forests exist in the tropics. In temperate countries, industrial plantations contain largely conifers (especially larch, pine, and spruce) or fine hardwoods (ash, beech, and oak). In tropical and Mediterranean countries, plantations consist of

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44 I Forest Trees TABLE 2-3 Growth Rates of Selected Tropical Plantation Tree Species Yield Rotation Plantation Development Species (m3ha-'a~~')0 (years) Scott Paper Co., Costa Rica Pious caribaea 40 8 Aracruz Florestal, Brazil Eucalyptus gratis 35 7 Jari Florestal, Brazil Gmelir~n arborea 35 10 Jari Florestal, Brazil P. caribaea 27 16 Fiji Pine Commission P. caribaea 21 12-15 Seaqaqa plantations, Fiji swiete,Zia macrophylla 14 30 Viphya Pulpwood Project, P. patula 18 16 Malawi Commonwealth New Guinea Araucaria spp. 20 40 Timbers, Papua New Guinea Paper Industries Corp. of Albizzia falcatarin 28 10 the Philippines Shiselweni Forestry, E. gro'~dis 18 9 Swaziland Usutu Forest, Swaziland P. patula 19 15 n Cubic meters per hectare per annum. SOURCE: J. Evans. 1982. Plantation Forestry in the Tropics. New York: Oxford University Press. Reprinted by permission of Oxford University Press. mainly eucalypts, Gmelina (widely used for timber), mahoganies, pines, and teak, although many other species have potential for specific conditions, such as laurel and Leucaena. The area of plantations (both industrial and those not strictly for industrial purposes) planted in the tropics totals 1.5 million ha annually with a current cumulative standing area of approximately 11 million ha. Growth rates for tropical plantation species are shown in Table 2-3. By comparison, the mean annual growth of a naturally occurring climax tropical forest is rarely greater than 3 to 4 m3 per hectare. Constraints and Opportunities of Land Use Systems Although managed breeding programs are used in some areas, intensive forestry on a large scale is possible only in relatively simple ecosystems. For large-scale but low-intensity management, as for amen- ity, fuelwood, or protection forests (e.g., windbreaks), only low-cost breeding and regeneration programs are economically feasible for main- taining forests or afforesting impoverished landscapes. For small-scale, low-intensity forestry, as practiced to maintain ecosystems, feasible management could still include controlling the size and distribution of

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Multiple Uses of Forest Trees 145 clearings or reproduction patches. For more intensively managed areas in which large-scale afforestation or reforestation is needed, as in some tropical areas, the management technology may still require research and development. Current investment levels in land use systems are rarely high enough to duplicate the intensive breeding or conservation procedures used with agronomic crops, even for species currently used in industrial forestry. Even if high-genetic gains in productivity can be expected, investment is generally low. This may be due to the length of time required for forestry to provide investment returns and for genetic techniques to influence forest productivity. It may also be due to the misconception that nonindustrial uses are of limited value. Investors find little likelihood of immediate profit even though the long-term, societal benefits may be high. Research to develop faster breeding techniques and low-cost fores- tation programs for using selected stocks of many different species could induce more investment. Even when the economic use and value of forestlands can be feasibly and substantially enhanced by appropriate breeding, however, economic inhibitions continue to deter private sources from developing the genetic resource. INCREASING THE USEFULNESS OF TREE GENETIC RESOURCES Given the lack of knowledge about the nature and distribution of forest genetic resources, substantial efforts are needed in two other traditional stages of using plant genetic resources: plant exploration and evaluation. Both are necessary before sustained utilization of the re- sources can be assured. In addition, efforts should be organized to coordinate the exploration and evaluation of programs of various agencies and governments. Finally, programs are needed to test and conserve species whose potential value is not yet known. Exploration For a given species, its natural range must be explored and areas to which it has been introduced must be identified. Determination of its taxonomic status (relationship to other species) and study of its natural breeding system are also essential. Such information is reasonably well known for most of the temperate-zone species among the 100 tree species used in commercial plantations. From several hundred to a few thousand other potentially valuable species, particularly in the tropics, are not yet widely used either for commercial purposes or for rural

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: e- ~ :- ~ If ~ ~ ed~na.1 quinine for the treat- ment of ~malada was od~na~lly dredged Cam the ~^ of the age, a ~~^ South eden gin West. ~ U.S, ~ I. ~ a , .:~s ,.. a,.... ....... development. Li~leis known about ~diratthbsute~s,status, or d~istrL bubon(~B~rl~ey and van Cbrl~o~i~,1 ~ ).Por~man~y,t~heir~=produrdve sv~s~m,ro~ulat~nvariab~on,anddistributio~na~ al~solittl~eun~de~rstood. Exsi~ tieldt~riaiscoup~led With molecu1aror~locbe~mIcalanalysesa~re needed to deermi~ne the pattern and extent of genetic vadatio~ns far mangy species. Well~des~i~ned, replicated experiments on an a~rraY of geld sites provide data on the vadabon among populations in su~~lval, growth, p~ductiVi~ty/ and qualitative chamct~e~stics. Through preen finance testing (repeated trials on a range of sites), estimates can be made off the importance of ge~notype~e~nvironment Infection effects. This in , , , tarn, indi~tes the extent to enrich individual populations should be conserved sepsa^~Iy and also bred separately in the future. (Details of the design/ management, and assessment of such trials am given in Budey and Wood Q976] and, far multipurpose ~es, in Bu~ev and Mood [1987] ~

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Multiple Uses of Forest Trees / 47 Coordination When a species is indigenous to several countries and is useful in several others, great advantages accrue from organizing coordinated programs of exploration, collection, and evaluation. Such coordination would minimize the number of collecting missions and maximize both the comparability of sampling within the natural range and of testing in experimental locations. Often such projects have been undertaken by organizations in developed countries. Examples include the Com- monwealth Scientific and Industrial Research Organization in Australia (many eucalypts), Centre Technique Forestier Tropical in France (various tropical species), the Danish Forest Seed Center (Gmelina, teak, some tropical pines), and the Oxford Forestry Institute in the United Kingdom (Central American pines and hardwoods, some Asian tropical pines, and some indigenous African acacias). The Food and Agriculture Organization of the United Nations, in a program for arid-zone species supported in part by the International Board for Plant Genetic Resources, took a somewhat less centralized approach by asking research institutions within the natural-range coun- tries to make collections and pool them for distribution to institutions interested in evaluating them. In either system, herbarium specimens are collected for taxonomic study, and preliminary observations of breeding systems can also be made during the exploratory phase. Development of Programs for Untested Species For species that are without clear potential production value and that are not adequately included within ecosystem reserve areas, no programs to conserve genetic resources exist. Species that might serve vital functions for ecosystem productivity, recreation, or other diffuse values, but that are not included in protected areas, have no constituency to encourage investment in their management or conservation. The iden- tification and management of such populations for their genetic resources have received increasing attention in conservation efforts (Schoenwald- Cox et al., 1983; Wilson, 1988~. RECOMMENDATIONS Industrial production forestry and the other land use systems de- scribed in this chapter are evolving in response to the changing needs of people, the environment, and industry. To maintain the widest

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In As, Farmer tags ~ Spine the to collect resign. Detective reserves is proposed by same Exerts as ~ AL ~1~ income produdng resources to-be collected ~hi.~le p~se~i~n~ tams. Cedit~: Fog and ~gd!cult~.re Or~ani.~Lon. genetic array of options aortae fi~,itis n.ecessa) to understand and work with the exisdngs ~ care of (e~nedc vain in trees p~:s~p/~, ~ '~) ~ff,gf~f~s~. C~oopera~on among natio~ns.or between 3.ati~onal~and inte~rnationa1 pro~g:~msca.~n m.a~kee~fEcie~ntuse~o~fJ~i~.i~ted~n~dsan~d echnica~lcapaci~ties . . to promote exp~loraSo~n~and evaluation. Explo~=tison is necessary to dee~nine file nature and extant of genetic d~e~i~ b~ &~e~ age .~ species. Data on the ~e-og~p~hic dist~dbudon,taxon~om~y/ biology' and ecology of a species maybe neededt!osupplemeniLn~o~ledgeo-bta~i~ned from materialaIreadyin reserves or collechons~ The in~rmabon~athered through evaluation is crucial for making Rise decisions about Unseating and using species end populations. For many s~peciest~hat originate in a country or region where they may have relatively ~litt~Ie value but may be of maioreco~n~o~.tsig~niEcance

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Multiple Uses of Forest Trees / 49 elsewhere, three questions are raised: (1) Who should conduct and pay for exploration and any subsequent in situ conservation? (2) Who should conduct and pay for testing and establishing ex situ conservation stands? (3) Should the country of origin restrict export or charge origin fees for its genetic material? These issues have yet to be raised seriously in forestry, but they are undergoing major international debate for food crop species. Forest genetic resources programs should conserve species that lack clear present or potential value and those that have known potential value. Breeding programs that do not rely on expensive testing or lengthy regeneration techniques should be instituted for a large number of species, especially those being newly brought into genetic management programs. For the many hundreds of species of potential value, genetic surveys and sampling for multiple populations are needed and might be combined with preliminary breeding operations. Of the species currently being tested or considered for multiple breeding populations, such as teak in Thailand (Wellendorf and Kaosa-Ard, 1988), most would require an increase of 5 to 10 times the current funding. To develop the species of known potential value, an order-of-magnitude increase in the number of species included in exploration and testing programs is needed. To conserve the species that lack clear current or potential value, additional efforts are needed.

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