The model develops a friction factor as a function of Reynolds number for various percentage coverage of plants. Percentage coverage is a variable used by ecologists and is easily determined from aerial surveys.
Artificial plant arrangements are mounted in a clear acrylic frame, backlit from underneath, and, using a mirror, are photographed from above from sixty feet away. From the photographic data, fractal dimension and lacunarity can be determined as a function of percentage coverage. Then the arrangement is placed in a wind tunnel and drag forces on the plant-frame system measured for upstream velocities ranging up to thirty-five miles an hour. Plots of friction factor as a function of Reynolds number are generated and then collapsed into single curves using the photographically generated variables.
Vorticity and flow through the plant canopy causing plant oscillation are not considered.