Amboyna Burl
Burl Wood
Burl wood is a type of wood used by artists to create sculptures and other items, such as clocks and even some forms of furniture. Burl wood is highly prized by artists because of its unique shapes and ring patterns. Burl wood is a type of fast growing, abnormal growth found on some trees. Burl wood grows because the tree has experienced some sort of environmental stress or damage. This is often caused by either a fungal attack or an attack by insects.
The number of trees that produce burl wood is quite low. In addition, certain areas tend to create more burl wood than others, because all or many of the trees in a particular location are likely to be attacked by the same fungus or insects. Certain species also tend to be more susceptible to attacks and, therefore, more likely to develop burl wood. For this reason, certain types of burl wood are more rare and prized than others. Often, a tree that has developed burl wood is still quite healthy. In fact, many trees with burl wood can go on to live for many more years. Other trees develop burl wood offshoots that are so large and heavy that they create additional stress on the tree and can cause the tree to die.
When used in woodcrafting, burl wood is removed from the tree, preferably after the tree has already died in order to avoid killing the tree. It is then cut open in order to review the pattern inside. Sometimes, a single burl wood offshoot can produce several different pieces for an artist to work with.
Some burl wood offshoots develop regular growth rings that simply grow at an accelerated rate. This type of burl wood is not as sought after by artists as other forms of burl wood, because the patterns on this wood are not as interesting to look at. The majority of woodworking artists prefer burl wood that grows in irregular patterns that swirl and contain what are referred to as eyes – small spots that develop on the wood. While pieces with unusual patterns are the most desired form of burl wood, they are also the most difficult to work with. This is because the irregular patterns of burl wood make it harder to saw, chisel, and cut without splitting the wood or accidentally cutting it in the wrong direction.
Environmental Profile
The environmental profile of this species within its natural habitat is reported to be Vulnerable in the Philippines. Its status in Indonesia and parts of Malaysia is officially classified as either Extinct, Endangered, Vulnerable, or Rare, and it has been assigned a conservation category of Insufficiently Known in Vietnam which means that the species is suspected to be either Extinct, Endangered, Vulnerable, or Rare. The actual status of the species in Indonesia, Malaysia, and Vietnam is unknown because of inadequate information (Source - World Conservation Monitoring Center - 1992 ).
Distribution
This species is one of about 60 in the Pterocarpus genus, which is reported to consist of small to large trees distributed throughout the tropics. Pterocarpus indicus is reported to be indigenous to Malaysia, but is also found in the Philippines, Borneo, Burma, New Guinea, and the Malay Archipelago. It is also reported to be often planted as an ornamental and a shade tree in several regions, including India, along roadsides, and in gardens because of its flowers and handsome foliage.
Product Sources
Some material from this species is reported to be available from environmentally responsible or sustainably managed sources.
Tree Data
The tree is reported to reach a height of up to 100 feet (30 m) or more, with a trunk diameter of 24 to 36 inches (60 to 90 cm). It develops boles that are often of rather poor form and high, wide-spreading buttresses.
Sapwood Color
The sapwood is whitish or straw-colored, and is clearly demarcated from the heartwood.
Heartwood Color
The color of the heartwood ranges from blood red, golden brown, light yellow, reddish brown to a distinct red. It darkens upon exposure.
Grain
The grain is typically interlocked, sometimes wavy. The wood is often marked with little twisted curls and knots which give a pronounced fine figure. Flat sawn surfaces are reported to have a flame figure, and quartersawn surfaces usually exhibit a ribbon figure.
Movement in Service
Properly seasoned timber is reported to be dimensionally stable, and retains its shape well after manufacture.
Turning
The material is reported to respond well to ordinary tools to yield clean, turned surfaces.
Polishing
Polishing characteristics are reported to be excellent.
Strength Properties
The bending strength of air-dried wood of the species is similar to that of Teak, which is considered to be strong. Strength in compression parallel to grain is in the high range. Other species in this range include Teak, White oak, and Hard maple. It is moderately hard and resistant to wearing and marring. It is a heavy wood. The wood is high in density.