A burl, originating from the British word burr, is an abnormal tree growth, usually rounded, that has a number of new branch ends or buds coming from it. A burl is also a term for a localized distortion in wood or veneer, formed by branches, as in Birdseye maple.
A burl is formed because the tree undergoes stress, from the environment or from human interaction. A majority of burls occur beneath the tree, as part of the root system. In a root system of a tree, there may be a number of these growths connected by strings of roots.
Some trees create burls that are of a very large size, redwoods, for instance.
These large burls can grow out into new trees themselves.
Uses of Burl Wood
The burl has become highly prized for its wood, because of its peculiar, unique qualities and its striking patterns in the grain. Birdseye maple is a wood which is not burl wood, but is valuable because of its similarity to the patterns and characteristics of burl wood.
Central Massachusetts and Connecticut are known for producing special burl woods. Wood sculptures, bowls, and furniture are made from the wood of burls.