Scientific Name
Trema sp.
Trade Name
Mbessi
Family Name
Ulmaceae
Common Names
Mbessi, Menarong, Mengkirai
Regions of Distribution
Africa
Countries of Distribution [VIEW MAP]
Comoros
Common Uses
Balusters, Baskets, Bedroom suites, Boat building, Boxes and crates, Building construction, Building materials, Cabinetmaking, Canoes, Casks, Chairs, Charcoal, Chests, Concealed parts (Furniture), Construction, Core Stock, Decorative plywood, Desks, Dining-room furniture, Dowell pins, Dowells, Drawer sides, Fine furniture, Floor lamps, Food containers, Fuelwood, Furniture , Furniture components, Furniture squares or stock, Hatracks, Interior construction, Kitchen cabinets, Lifeboats, Light construction, Living-room suites, Moldings, Office furniture, Packing cases, Particleboard, Plywood, Radio – stereo – TV cabinets, Rustic furniture
Environmental Profile
| Abundant/Secure | ||||||||||||
| Rare | ||||||||||||
| Status has not been officially assessed |
Distribution Overview
The genus Trema consists of about 20 species, which are widely distributed in the tropical regions of the world.
Heartwood Color
| Brown | ||||||||||||
| Yellow | ||||||||||||
| Red | ||||||||||||
| Orange | ||||||||||||
| White | ||||||||||||
| Purple | ||||||||||||
| Pink | ||||||||||||
| Green/grey | ||||||||||||
| White to cream |
Sapwood Color
| White | ||||||||||||
| Yellow | ||||||||||||
| Brown | ||||||||||||
| Red | ||||||||||||
| Color not distinct from heartwood |
Grain
| Even | ||||||||||||
| Straight |
| Straight |
Texture
| Fine | ||||||||||||
| Medium | ||||||||||||
| Coarse | ||||||||||||
| Medium coarse to coarse |
Luster
| Medium | ||||||||||||
| Low |
Wood surfaces are reported to have a natural sheen
Natural Durability
| Non-durable | ||||||||||||
| Susceptible to insect attack | ||||||||||||
| Durable | ||||||||||||
| Resistant to powder post beetles | ||||||||||||
| Perishable | ||||||||||||
| Non-resistant to marine borers | ||||||||||||
| Susceptible to termite attack | ||||||||||||
| Susceptible to attack by pinhole borers | ||||||||||||
| Heartwood has very low resistance to decay |
It is recommended that freshly cut stock be dip-treated immediately after sawing to prevent blue stain
Odor
| Has an odor |
Toxicity
| Some toxic effects |
Drying Defects
| Checking | ||||||||||||
| Distortion | ||||||||||||
| Uneven Moisture Content | ||||||||||||
| Discoloration | ||||||||||||
| Ring Shakes |
Ease of Drying
| Fairly Easy | ||||||||||||
| Moderately Difficult to Difficult | ||||||||||||
| Slowly | ||||||||||||
| Reconditioning Treatement | ||||||||||||
| Very good seasoning properties |
Kiln Drying Rate
| Naturally dries at a moderate speed | ||||||||||||
| Naturally dries slowly |
Tree Size
| Tree height is 60-70 m | ||||||||||||
| Trunk diameter is 100-150 cm | ||||||||||||
| Trunk diameter is 150-200 cm | ||||||||||||
| Sapwood width is 0-5 cm | ||||||||||||
| Trunk diameter is 200-250 cm | ||||||||||||
| Tree height is 50-60 m | ||||||||||||
| Tree height is 30-40 m | ||||||||||||
| Tree height is 40-50 m | ||||||||||||
| Tree height is 10-20 m | ||||||||||||
| Bole length is 20-30 m | ||||||||||||
| Tree height is greater than 70 m |
Certified Source
| Certified Source |
Comments
Species in the genus are more valuable in their role of soil conservation and reclamation than as a source for timber
Blunting Effect
| Little | ||||||||||||
| Medium dulling effect on cutting edges |
Boring
| Very good to excellent results | ||||||||||||
| Fairly easy to very easy | ||||||||||||
| Easy |
Boring operations are rather easy with ordinary machine tools
Carving
| Good results |
Cutting Resistance
| Fairly easy to saw |
Gluing
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results |
Mortising
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Slight to moderate blunting effect on cutters | ||||||||||||
| Mortising operations are fairly easy |
Moulding
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Works fairly well with machine tools |
Movement in Service
| Fair to Good Stability – Medium Movement | ||||||||||||
| Excellent Stability – Small Movement |
Nailing
| Fair to Good Results | ||||||||||||
| Pre-Boring Recommended | ||||||||||||
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results |
Planing
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Special attention required |
The timber is described as very soft and generally planes to yield a smooth surface. Material with irregular grain requires a reduced cutting angle of 15 degrees to prevent tearing
Resistance to Impregnation
| Resistant heartwood | ||||||||||||
| Resistant sapwood | ||||||||||||
| Sapwood is permeable | ||||||||||||
| Heartwood is extremely resistant |
Response to Hand Tools
| Easy to Work | ||||||||||||
| Fairly Difficult to Difficult to Work | ||||||||||||
| Easy to machine |
The timber is described as very soft
Routing & Recessing
| Routing is easy | ||||||||||||
| Good routing qualities |
Sanding
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Satisfactory sanding properties |
Screwing
| Pre-boring recommended | ||||||||||||
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results |
Turning
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Good results |
Veneering Qualities
| Veneers moderately easy | ||||||||||||
| Difficult to veneer | ||||||||||||
| Veneers easily | ||||||||||||
| Suitable for peeling |
Steam Bending
| Fair to Good Results |
Painting
| Fair to Good Results | ||||||||||||
| Very Good to Excellent Results | ||||||||||||
| Fairly Easy to Very Easy |
Polishing
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results |
Staining
| Fair to Good Results | ||||||||||||
| Very Good to Excellent Results | ||||||||||||
| Fairly Easy to Very Easy |
Varnishing
| Fairly Easy to Very Easy | ||||||||||||
| Fair to Good Results | ||||||||||||
| Very Good to Excellent Results |
Strength Properties
| Compression strength (parallel to grain) = medium | ||||||||||||
| Bending strength (MOR) = medium |
It is closer in strength to Mahogany than either Teak or White oak, which have higher bending strength
Numerical Data
| Item | Green | Dry | English |
| Bending Strength | 6174 | 9555 | psi |
| Maximum Crushing Strength | 3087 | 5684 | psi |
| Shearing Strength | 1470 | psi | |
| Stiffness | 1127 | 1294 | 1000 psi |
| Item | Green | Dry | Metric |
| Bending Strength | 434 | 671 | kg/cm2 |
| Maximum Crushing Strength | 217 | 399 | kg/cm2 |
| Shearing Strength | 103 | kg/cm2 |
References
Bolza, E., Keating, W.G.,1972,African Timbers – the Properties, Uses and Characteristics of 700 Species,C.S.I.R.O. Div. of Building Research
Desch, H. E. 1954. Manual of Malayan Timbers – Volume II. Malayan Forest Records, No. 15. Malaysia Publishing House Ltd., Singapore.
Schneider, E.E. 1916. Commercial Woods of the Philippines: Their Preparation and Uses. Bulletin No. 14. Department of the Interior, Bureau of Forestry, Manila, Philippines.