Changes

'''== Trade groups'''==

*'''Nyatoh''': lightweight to medium-heavy hardwood, e.g. ''Payena'' ''acuminata'' (Blume) Pierre, ''P.'' ''lanceolata'' Ridley, ''P.'' ''lucida'' (Wallich ex G. Don) A.DC., ''P.'' ''maingayi'' C.B. Clarke, ''P.'' ''obscura'' Burck (partly).

*'''Bitis''': heavy hardwood, e.g. ''P.'' ''leerii'' (Teijsm. & Binnend.) Kurz, ''P.'' ''obscura'' Burck (partly).

*'''Nyatoh'''*Nyatoh: padang (En)

*'''Bitis'''

''Payena'' consists of about 15 species and is distributed from Burma and the Andaman Islands east to the southern Philippines and Borneo and south to Sumatra and Java. The genus seems to be of western Malesian origin. Most species are found in Peninsular Malaysia, Sumatra and Borneo. ''P.'' ''acuminata'' , ''P.'' ''leerii'' and ''P.'' ''lucida'' are the most widespread species, occurring almost throughout western Malesia.

Bitis is much more durable and is used for heavy constructional work, paving blocks, agricultural implements and turnery and also for heavy-duty flooring, posts, and door and window frames. Although ''Madhuca'' ''utilis'' (Ridley) H.J. Lam ex K. Heyne, ''Palaquium'' ''ridleyi'' King & Gamble and ''Palaquium'' ''stellatum'' King & Gamble are the main bitis-producing species, ''Payena'' ''leerii'' may also supply this type of timber.

The latex of several ''Payena'' species (especially ''P.'' ''leerii,'' ''P.'' ''obscura'' ), called gutta-percha, has been used to insulate submarine cables, in dentistry, in orthopaedics for fracture splints, for the manufacture of surgical instruments and for covering golf balls, and also to haft knives and to make blowpipe mouthpieces, and as a substitute for chewing gum. At present, its main application is in dental clinics where it is used as filler for people who are allergic to synthetic fillers. However, the most important gutta-percha producing species is ''Palaquium gutta'' (Hook.f.) Baillon.

The fruits of some species ( ''P.leerii'' ''leerii,'' ''P.'' ''acuminata'' and ''P.'' ''lowiana'' ) are edible but there is little flesh on them. They taste slightly like the fruits of ''Manilkara'' ''zapota'' (L.) P. v. Royen. The roots of ''P.'' ''lucida'' are used in local medicine; a decoction is given to women after childbirth.

Timber from ''Payena'' trees is not traded separately. It is not generally available in commercially important quantities. The timber is usually mixed with that of other ''Sapotaceae'' genera and collectively traded as nyatoh. The export of nyatoh sawn timber from Peninsular Malaysia decreased from 16 500 m³(with a value of US$ 2.1 million) in 1981 to 9500 m³(with a value of US$ 1.3 million) in 1986. From 1986 onward the export increased to 32 500 m³(with a value of US$ 6.1 million) in 1990, but in 1992 only 8000 m³was exported with a value of US$ 2.8 million. Large amounts of nyatoh are also exported from Sarawak and Sabah; the export of round logs from Sabah was 65 000 m³(worth US$ 6.3 million) in 1987, and in 1992 the export of logs was 14 000 m³and that of sawn timber 8500 m³with a total value of US$ 4.4 million.

''P.'' ''leerii'' was an important species for the production of gutta-percha, which was principally collected from trees growing in the wild. However, by 1980 the exports of gutta-percha had declined to less than 50 t annually, and it is still declining, due to the replacement by synthetic plastics.

A general description of nyatoh and bitis is given here. The timber of ''Payena'' species is traded in these trade groups which also include ''Palaquium'' , ''Pouteria'' and ''Madhuca'' species. ''Payena'' timber, with its density of 580-1070 kg/m³at 15% moisture content, can be classified as belonging to the heavier nyatoh timbers and occasionally ( ''P.'' ''leerii,'' ''P. obscura'' ) to the lighter bitis timbers. Nyatoh and bitis are not well demarcated groups of timber, showing much overlap. The arbitrary limit lies at 850 kg/m³. In East Malaysia, bitis is not accepted as a separate group.

'''Nyatoh ''' is a light to medium-weight, moderately hard to hard red meranti-like wood. The heartwood is pinkish-brown to reddish-brown and only moderately distinct from the lighter sapwood. The density is (420-)550-800(-850) kg/m³at 15% moisture content; that of the majority of the commercial supply is 600-700 kg/m³. The grain is shallowly interlocked, texture moderately fine and even.

The sawing properties are variable, probably depending on the species, but variation may also be large within species. Some nyatoh-producing species contain silica, which makes the timber difficult to work (e.g. ''P.'' ''endertii'' and ''P.'' ''lucida'' ). Gum may accumulate on cutters. Nyatoh is easy to polish when the grain is properly filled. The wood is easy to turn. Pre-boring for nails and screws is advised because of easy splitting. Gluing gives no problems. The fine grain and colour make it suitable for veneer; it can be peeled at a 91peeling 91° peeling angle without pretreatment. Sometimes the wood is figured and then the veneer can be very attractive, especially when radially sliced. Peeling is reported as easy to fairly difficult, and a good plywood can be made from the timber.

'''Bitis ''' comprises heavier timber, with density of 850-1150 kg/m³at 15% moisture content. The heartwood is reddish-brown to dark brown, and clearly differentiated from the lighter sapwood. The grain is fairly straight, texture moderately fine and even. Bitis is very hard and strong, and much more durable than nyatoh.

The latex from the inner bark of the tree absorbs oxygen and becomes brittle. Gutta-percha is the purified, coagulated latex. It is a whitish-grey to yellowish-brown tough substance, consisting essentially of gutta hydrocarbon with some resin. It is pliable at 25-30C30° C, plastic at 60C60° C, and it melts at 100C 100° C with partial decomposition; it is insoluble in water and resistant to acids. At 60C 60° C gutta-percha can be moulded into a desired shape, which is retained on cooling. It is defined as a transisomer of rubber. The quality of gutta-percha depends on the ratio of poly-isoprene and resin; the best quality contains about 80% poly-isoprene, inferior quality much less, sometimes only 20%. ''P. leerii'' provides a gutta-percha of fairly good quality, containing 43-49% resin and 51-57% poly-isoprene. However, the quality is less than the gutta-percha from ''Palaquium gutta'' . The resin contains ß-amyrineacetate. The seeds of some species are reported as poisonous; extracted kernels of ''P. lucida'' contain about 30% saponin.

*Medium-sized to large trees, with latex, up to 45(-50) m tall, with usually columnar, cylindrical or fluted and buttressed bole, up to 100 cm in diameter; outer bark smooth, irregularly cracked, fissured or scaly, grey to brown, inner bark soft and fibrous, pink, red or reddish-brown; twigs slender and terete, usually hairy or scurfy. *Leaves alternate on branch shoots, spiral on leader shoots, simple and entire, mostly acuminate, usually glabrous above and more or less pubescent beneath when mature; midrib generally prominent on both sides, secondary veins straight, curving towards apex and joined near leaf margin, tertiary veins mostly descending from marginal conjunctions of secondary veins and ramifying towards the midrib; petiole of even thickness throughout its length; stipules early caducous. *Inflorescence a small, axillary (sometimes pseudo-terminal) fascicle, 1-many-flowered. *Flowers bisexual; sepals 4, 2 outer ones thick and fleshy, 2 inner ones thinner; corolla (7-)8(-9)- lobed, with short tube, glabrous, white or yellowish; stamens 13-20(-30), inserted at the throat of the corolla tube, with short filaments and acute anthers; pistil 1, with globose or conoidal (4-)6-8(-9)-celled ovary and long style. *Fruit a berry with persistent and incrassate sepals and style and fleshy pericarp, 1(-2)-seeded. *Seed with a thin crustaceous testa and long narrow hilum; endosperm abundant, cotyledons thin and flat. *Seedling with epigeal germination, with strongly developed taproot; first pair of leaves opposite or subopposite, subsequent leaves spiral and soon similar to leaves of adult trees.

*Heartwood deep pink, red, red-brown or purple-brown, sometimes with dark streaks, distinctly to indistinctly demarcated from the pale red sapwood. *Grain shallowly to moderately interlocked, sometimes wavy. *Texture moderately fine to slightly coarse; wood dull, sometimes with a sour smell when freshly sawn. *Growth rings indistinct to the naked eye; vessels and parenchyma indistinct to barely visible to the naked eye; rays not distinct without a lens.

*Growth rings faint or absent, if present marked by differences in spacing of tangential parenchyma bands, and in fibre wall thickness on either side of the ring boundary. *Vessels diffuse, (4-)6-14(-25)/mm², mainly in radial multiples of 2-5(-8), in a radial or radial to oblique pattern, round to oval, average tangential diameter 100-190μm190 μm; perforations simple; intervessel pits alternate, round, 5-7μm7 μm; vessel-ray pits mainly confined to the upright and square cells, mostly large and simple, horizontally to vertically elongated or round, partly half-bordered, scarce in procumbent cells; helical thickenings absent; gum-like deposits and tyloses sometimes present. *Fibres c. 1200-1800μm 1800 μm long, non-septate, mostly medium thick-walled, with simple to minutely bordered pits mainly confined to the radial walls. *Parenchyma abundant, diffuse, diffuse-in-aggregates or in fine discontinuous to continuous 1-2-seriate wavy to straight bands forming a reticulate pattern, 4-8 lines per radial mm, in 6-9-celled strands. *Rays 12-15/mm, 1-2(-3)-seriate, up to 800μm 800 μm high, heterocellular with (1-)2-5 marginal rows of upright and square cells and procumbent body cells. *Crystals absent. *Silica bodies often present in ray cells.

Species studied: ''P. acuminata, P. leerii, P. lowiana, P. lucida, P. maingayi, P. obscura'' .

Water shoots often have unusually large leaves. There seems to be no definite time for flowering and fruiting. Flowering and fruiting trees can be found throughout the year, and sometimes a single tree bears flowers and fruits at the same time. In plantations of ''P.'' ''leerii'' on Java, with initial planting distances of 2 m × 2 m, the canopy closed after 10-12 years. The trees then reached 6-13 m in height. They flower and fruit already at an age of about 7 years.

''Payena'' is generally included in the tribe ''Madhuceae,'' and is considered as closely related to ''Madhuca.'' Unlike ''Madhuca,'' ''Payena'' does not vary much in floral characters (4 sepals, 8 petals, 16 stamens, 8 ovary cells, rarely otherwise), but the shape of the leaves and stamens, and the number of seeds per fruit may vary. ''Payena'' is often recognized easily by the tendency of the leaves to be arranged alternately on the twigs and by the tertiary veins of the leaves descending from the marginal conjunction of secondary veins. However, it is sometimes difficult to identify herbarium specimens of ''Payena'' , especially sterile ones, even to the genus. Some species are apparently very closely related and may cause problems in identification, e.g. ''P.'' ''acuminata'' and ''P.'' ''maingayi,'' ''P.'' ''leerii'' and ''P.'' ''obscura.'' The most deviating species is ''P.'' ''dasyphylla'' with its woolly red pubescence and possibly purplish-red flowers; it is often placed in a separate section ''Purpureopayena'' v. Bruggen. The remaining species cannot be subdivided into groups as they show interwoven relationships and are placed in the section ''Payena'' , having a less dense pubescence and always whitish flowers.

The wood properties of nyatoh are close to those of makoré ( ''Tieghemella'' spp.) from western and central Africa.

''Payena'' trees are most commonly found in primary mixed dipterocarp forest, but occasionally also in secondary forests and at forest edges, e.g. along rivers. They occur from the lowland up to 1500(-2000) m altitude, on a variety of soils, from peat swamps to podzols, and from clayey to sandy soils, rarely on limestone. ''Payena'' trees generally belong to the middle or uppermost storey of the forest, but are not emergents. Locally, ''Payena'' species are not uncommon, although they usually occur scattered, e.g. ''P.'' ''acuminata'' in Java and Borneo, ''P.'' ''leerii'' in Sumatra and Borneo, ''P.'' ''lucida'' in many areas, and ''P.'' ''obscura'' in Peninsular Malaysia.

For plantations of ''P.'' ''leerii'' , high-rainfall areas at medium altitudes and loamy soils are preferable.

''P.'' ''leerii'' is usually propagated by sowing seed in a nursery. Fresh seed should be used, as viability declines rapidly. Seeds of ''P. lucida'' are 2-3 cm long and germinate in 2-5 weeks. When sown within a week of harvesting, up to 80% of the seeds may germinate. Saplings are planted at a spacing of 2 m × 2 m in the field. Mature trees usually provide fruits abundantly. Some species ( ''P.'' ''acuminata,'' ''P.'' ''maingayi'' ) occasionally produce fruits with more than 1 seed, but these seeds are reported to be less viable.

'''== Silviculture and management''' == In young plantations of ''P.'' ''leerii'' for gutta-percha production, ''Paraserianthes'' ''falcataria'' (L.) Nielsen is often used to provide shade. In the first 7-8 years after planting, weeding is necessary about 4 times per year, later only once a year. When the canopy has closed 10-12 years after planting, weeds are shaded out completely, and the ground is covered with fallen leaves.

Nyatoh trees are reported susceptible to the fungus ''Corticium'' ''salmonicolor.'' In Peninsular Malaysia, a large species of longhorn beetle has been reported to attack living nyatoh trees. The larvae bore long tunnels, especially at the base of the trunk, and may severely damage the timber.

The gutta-percha of planted trees of ''P.'' ''leerii'' can be harvested for the first time after about 12 years. Usually a vertical herring-bone cut is made in the inner bark in the early morning. The latex hardens to a sticky mass. The trees must be allowed to rest for about 1.5 year before the next harvest. Vigorous tapping can easily cause the trees to die. Methods have been developed to extract the leaves instead of the bark. An excellent product can be obtained, but the process is very labour-intensive. Gutta-percha is usually traded and transported in vacuum zinc containers. Gutta-percha from ''P.'' ''leerii'' is often mixed with the products from other ''Sapotaceae'' trees.

No information is available on the yield of ''Payena'' timber. The annual yield of gutta-percha from ''P.'' ''leerii'' is not high; in Java (Indonesia) much less than 1 kg of dry latex per average tree (about 20 m tall), usually even less than 200 g. A big tree in Perak (Peninsular Malaysia) was reported to produce about 200 g annually. These figures are much lower than those for ''Palaquium'' ''gutta.''

At the end of the 19th Century, the latex from ''Sapotaceae'' trees, including ''Payena'' , was important. Trees were often felled to obtain gutta-percha; this resulted in the destruction of such trees over wide areas. In Peninsular Malaysia, ''P.'' ''leerii'' and other species producing gutta-percha were protected a century ago. However, in many places trees were felled on a large scale well into the 20th Century for gutta-percha and for timber. Many ''Payena'' species occur scattered in the forest which makes them liable to genetic erosion and hence extinction.

Although gutta-percha still enters commerce in small quantities, the main product of ''Payena'' species including ''P.'' ''leerii'' , is probably timber. Prospects for gutta-percha do not seem to be very promising, as it is being replaced by synthetic plastics. The trees have a very low annual yield of gutta-percha per ha and procedures for collection are very labour-intensive.

* van Romburgh, P., 1903. Les plantes à caoutchouc et à gutta-percha cultivées aux Indes Néerlandaises [Rubber and gutta-percha plants cultivated in the Netherlands Indies]. G. Kolff & Co, Batavia. 208 pp. | '''10''' | * Wong, T.M., 1981. Malaysian timbers - nyatoh. Malaysian Forest Service Trade Leaflet No 54. Malaysian Timber Industry Board, Kuala Lumpur. 12 pp. == Selection of species ==