• Pernestål, K.
  Department of Physics, Swedish University of Agricultural Sciences
  
• Jonsson, B.
  Department of Biometry, Swedish University of Agricultural Sciences
  
• Larsson, B.
  Department of Biometry, Swedish University of Agricultural Sciences
  

A simple model for density distribution within an annual ring is proposed. The model originates from the concept that a tree has two growing modes "early" and "late" wood mode respectively and that during a growing season there is transition from the first to second. An annual ring is described by six parameters. The use of the model is discussed and a number of possible "measures" are suggested. The advantages and limitations of the model is also discussed.