Ilex (PROSEA)
Introduction |
Ilex L.
- Protologue: Sp. pl. 1: 125 (1753); Gen. pl., ed. 5: 60 (1754).
- Family: Aquifoliaceae
- Chromosome number: x= 9, 10; no counts for Malesian species available but most other species have 2n= 36 or 40
Vernacular names
- Mensira (trade name). Holly, ilex (En). Brunei: bengkulat
- Malaysia: bangkulatan (Sabah), bengkulat (Sarawak), mensirah (Peninsular).
Origin and geographic distribution
Ilex comprises about 400 species which occur in tropical, subtropical and temperate regions of the world with centres of diversity in North America and eastern Asia (mainly China). The number of Malesian species is roughly estimated to be about 80.
Uses
The wood of Ilex is used for house building, door and window frames, interior finish, furniture, household utensils, turnery, carving, tool handles, pencils, chopsticks, matches, packing cases, and also for plywood and moulding.
The roots of I. cymosa have been used medicinally in a decoction for fever.
Production and international trade
There are no exact figures on export and trade of "mensira". Mensira is not of commercial importance in Malaysia, but in Indonesia it is considered a commercial timber. Small amounts are occasionally imported in mixed parcels by Japan from Papua New Guinea and the Solomon Islands. In 1996 Papua New Guinea exported about 2630 m3of Ilex logs at an average free-on-board (FOB) price of US$ 99/m3.
Properties
Ilex yields a lightweight to medium-weight hardwood with a density of 490-680 kg/m3at 15% moisture content. Heartwood white to pale yellow, darkening to yellow-brown upon exposure, not clearly differentiated from the sapwood; grain straight; texture fine and uneven due to the broad rays; wood with conspicuous flecks on tangential surface and silver grain on radial surface. Growth rings generally indistinct, occasionally rather distinct as darker bands due to fewer parenchyma; vessels moderately small to medium-sized, mostly in radial multiples of 2-3, occasionally solitary, open; parenchyma moderately abundant, apotracheal diffuse-in-aggregates, moderately distinct with a hand lens; rays of 2 distinct sizes, very fine and moderately broad to very broad, the broad ones conspicuous to the naked eye; ripple marks absent.
Shrinkage is moderate to high and the wood is not easy to season as it tends to split slightly along the broad rays. The wood is easy to work. It is non-durable and is highly susceptible to sap-stain. The sapwood may be susceptible to Lyctus .
See also the tables on microscopic wood anatomy and wood properties.
Botany
Evergreen, dioecious shrubs or trees up to 20(-40) m tall; bole sometimes with small buttresses, up to 70(-120) cm in diameter; bark surface smooth or warty, white to pale grey or grey-brown, inner bark thick, coarsely gritty, grey-brown to yellowish-brown, no exudate. Leaves arranged spirally, simple, often leathery, entire or toothed; stipules absent or minute. Flowers in an axillary cyme or fascicle, rarely solitary, 4-6-merous; sepals persistent; petals imbricate and joined at base, white or greenish; ovary superior, (2-)4-9(-22)-locular with 1-2 ovules in each cell, stigma sessile, persistent in fruit. Fruit drupaceous with 3-10(-16) stones containing 1-2 seeds, red, purple or black.
In Peninsular Malaysia I. grandiflora Ridley has been observed to flower and fruit in mast years. Seed dispersal is mainly by birds; pollination by insects.
The Asian Ilex species are in need of a thorough taxonomic revision as most of the present information is only on a local scale or seems outdated. Within Malesia Ilex is the only representative of the family Aquifoliaceae , sometimes referred to as Ilicaceae .
Ecology
Most Malesian Ilex species are montane treelets or small trees. Several of them, among which most of the timber producers, form an exception and are found in primary or sometimes secondary lowland swamp and mangrove forest or in montane forest, particularly on poorly drained soils, up to 2400 m altitude. I. macrophylla prefers well-drained soils.
Silviculture Temperate Ilex species usually take 1-3 years to germinate and I. cymosa needs at least several months.
Genetic resources and breeding
There is probably little risk of genetic erosion as Ilex is not commonly harvested for its timber.
Prospects
Although Ilex wood may possess an attractive silver grain, its rareness and the generally small size of the trees limit its use.
Literature
40, 57, 66, 70, 151, 163, 209, 260, 267, 364, 373, 436, 526, 558, 595, 711, 829, 861, 933, 974, 1038, 1221, 1242.