University of Maryland Extension


a tree with burls

  • A burl is a large woody, rounded swelling, usually found on a tree trunk.
  • Burls can obtain a diameter up to 3 feet and may have many buds or sprouts.
  • "Burl wood" is prized for its unusual grain pattern. The grain of the wood swirls around each bud trace, forming interesting patterns in the wood.

  • The cause of most burls cannot be explained.
  • They may develop as a result of insects, bacteria, fungi, mistletoes, or environmental injury, such as freeze damage.
  • Sprouts arising from the burl may be pruned off, otherwise, no treatment is necessary.
  • Removal of the burl may damage the tree and is not recommended.

large burl
Burls can obtain a diameter up to 3 feet and may have many buds or sprouts


Rev. 2020

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