- Protologue: Prodr. 8: 196 (1844).
- Family: Sapotaceae
- Chromosome number: x= unknown
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).
- padang (En)
- Indonesia: nyatuh
- Malaysia: guttah, mayang (Peninsular), riam (Sarawak)
- Philippines: nato
- Burma: kanzwe
- Thailand: phikun-pa (Narathiwat), phikun-nok (Surat Thani), phikun-thuan (Surat Thani).
- Malaysia: nyatoh batu (Sabah, Sarawak).
Origin and geographic distribution
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.
Nyatoh is a general-purpose timber with properties similar to those of mixed consignments of red meranti. It is much used for the manufacture of fine furniture, decorative doors and panelling. The wood is suitable for moulding, skirting, cabinet making, joinery, interior finishing and flooring. It makes good-quality veneer which is used in the production of plywood. The nyatoh-producing species with lighter wood which usually belong to Palaquium and Madhuca are preferred, as they are less difficult to work. The timber is generally reported as moderately durable; it is perishable when exposed to the weather or in contact with the ground and is not very well suited for outdoor purposes.
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, 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.
Production and international trade
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 m3 was 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 m3 and that of sawn timber 8500 m3 with a total value of US$ 4.4 million.
Timbers of the bitis class are usually converted to scantling sizes, and sold unclassified. The bulk of the "seriah" sold in Singapore consists of logs of Palaquium and Payena and probably other sapotaceous trees imported from Indonesia.
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/m3 at 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/m3 at 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.
At 15% moisture content the modulus of rupture is 70-130 N/mm2, modulus of elasticity 10 000-18 000 N/mm2, compression parallel to grain 28-54 N/mm2, compression perpendicular to grain 2.5-7 N/mm2, shear 8.5-11(-17) N/mm2, cleavage 39-77 N/mm radial and 49-87 N/mm tangential, Janka side hardness 3700-7000 N and Janka end hardness 3900-7600 N.
The recorded rates of shrinkage of nyatoh are moderate, from green to 15% moisture content 1.3-3% radial and 2.3-4% tangential, from green to oven dry about 4.1% radial and 7.6% tangential. Air drying of 40 mm thick boards takes approximately 4 months, 25 mm thick boards about 2 months. The timber can be satisfactorily dried by using kiln schedule E (Malaysia). Form stability is medium to good when dry.
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 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.
Nyatoh is rated as only moderately durable. Graveyard tests with wood of P. acuminata in Indonesia showed an average service life in contact with the ground of only 1 year. It is prone to termite attack and susceptible to fungal attack, but not to powder-post beetles. Treated nyatoh timber can be very durable. However, the heartwood is very resistant to preservative treatment. The sapwood is less difficult to impregnate.
Bitis comprises heavier timber, with density of 850-1150 kg/m3 at 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.
At 15% moisture content the modulus of rupture is 105-170 N/mm2, modulus of elasticity 10 000-23 800 N/mm2, compression parallel to grain 65-90 N/mm2, compression perpendicular to grain 9-12.5 N/mm2, shear 10-17 N/mm2, cleavage c. 86 N/mm radial and 67 N/mm tangential, and Janka side hardness 14 400-14 900 N.
Bitis is difficult to dry; shrinkage rates are rather high (from green to 15% moisture content 3.0% radial and 4.0% tangential), and there is a tendency to surface checking. A mild kiln schedule (B in Malaysia) should be used.
Bitis is difficult to work, rapidly blunting saws and cutters due to the presence of silica, but it produces a smooth surface in planing and takes stain and polish satisfactorily. The timber tends to split in boring and mortising. Bitis is not suitable for veneer and plywood because it is difficult to peel.
Bitis timber is rated as durable and is resistant to termite and wood-rotting fungi attack. It is very difficult to impregnate.
Freshly felled wood often has a sour smell and a bitter taste. It lathers freely when rubbed with water. Dust from sawn nyatoh and bitis timber may cause irritation to skin and mucous membranes.
Wood of P. leerii contains 49% cellulose, 28% lignin, 17% pentosan and 0.5% ash. The solubility is 2.3% in alcohol-benzene, 1.7% in cold water, 3.6% in hot water and 11.4% in a 1% NaOH solution. Dry distillation of the wood produces 31% charcoal, 12% settled tar and 43% piroligneous liquor.
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° C, plastic at 60° C, and it melts at 100° C with partial decomposition; it is insoluble in water and resistant to acids. At 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 100-190 μm; perforations simple; intervessel pits alternate, round, 5-7 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. 1200-1800 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 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.
Growth and development
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.
Other botanical information
There used to be much confusion about the genera of Sapotaceae. This has recently been largely clarified. However, in the timber trade no distinction is made between timber from several Sapotaceae genera and species. Data on nyatoh timber given in literature can only rarely be linked to individual genera and species. It is not surprising that nyatoh is known as a variable timber, as many species and several genera are involved.
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.
Propagation and planting
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.
For timber production, pure stands of Payena are probably not a good management target. It is better to plant dipterocarp species with more valuable timber. Natural regeneration is usually plentiful in logged-over forests.
Diseases and pests
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.
No information is available on the harvesting of Payena timber. The logs have few defects.
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.
Nyatoh is a valuable but silviculturally neglected timber. It has good properties for indoor uses, and is in demand for furniture and plywood. However, nyatoh is variable in its properties, because it covers many species from several genera. Payena species have only very rarely been subjected to tests. Tests on properly identified logs are desirable, as well as research on all silvicultural aspects. The relation between timber properties and species urgently needs to be clarified, so that silviculturists will know which species to concentrate on.
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.
- Browne, F.G., 1955. Forest trees of Sarawak and Brunei and their products. Government Printing Office, Kuching. pp. 320-323.
- Burgess, P.F., 1966. Timbers of Sabah. Sabah Forest Records No 6. Forest Department, Sabah, Sandakan. pp. 447-455.
- Burkill, I.H., 1966. A dictionary of the economic products of the Malay Peninsula. 2nd edition. Vol. 2. Ministry of Agriculture and Co-operatives, Kuala Lumpur. pp. 1708-1711.
- Chudnoff, M., 1979. Tropical timbers of the world. USDA, US Forest Products Laboratory, Madison, Wisconsin. pp. 697-698.
- Desch, H.E., 1954. Manual of Malayan timbers. Malayan Forest Records No 15. Vol. 2. Malaya Publishing House, Singapore. pp. 538-557.
- Martawijaya, A., Kartasujana, I., Kadir, K. & Prawira, S.A., 1986. Indonesian wood atlas. Vol. 1. Forest Products Research and Development Centre, Bogor. pp. 102-106.
- Ng, F.S.P., 1972. Sapotaceae. In: Whitmore, T.C. (Editor): Tree flora of Malaya. A manual for foresters. Vol. 1. Malayan Forest Records No 26. Longman Malaysia SDN Berhad, Kuala Lumpur. pp. 388-439.
- van Bruggen, A.C., 1958. Sapotaceae of the Malaysian area 15. Payena. Blumea 9: 89-138.
- 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.
- 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
- R.H.M.J. Lemmens (general part, properties, selection of species),
- N. Tonanon (properties),
- R. Klaassen (wood anatomy)