How to calculate board feet<br>Measure the length, width, and depth in inches. Use a stiff tape measure to measure the length, width, and depth of the board. Each measurement should be taken separately and recorded in inches.
Length and width are different dimensions of a board.
The text mentions three dimensions, length, width and depth and length and width are two of the three and are different.
( z0 differ :ARG1 ( z1 dimension :op ( z2 long ) :op ( z3 width ) ) :ARG3 ( z4 distance-quantity :poss ( z5 board ) ) )
(z0 / differ-02
    :ARG1 (z1 / dimension
              :op1 (z2 / long-03)
              :op2 (z3 / width))
    :ARG3 (z4 / distance-quantity
              :poss (z5 / board)))
Length and width are different dimensions of a board .
z0 :ARG1 z1
z1 :op2 z3
z1 :op1 z2
z0 :ARG3 z4
z4 :poss z5