These Convex and Concave Spherical Densiometers allow accurate, one-person measurement of tree canopies. Measure forest overstory density from unobstructed sighting positions. Instruments use a spherical-shaped reflector mirror engraved with a crossshaped grid of twenty-four 1/4" squares.

To take readings, hold the instrument level, 12" to 18" in front of body and at elbow height. Assume four equi-spaced dots in each square of the grid and systematically count the dots equivalent to quarter-square openings. Multiply the total count by 1.04 to obtain percent of overhead area not occupied by canopy. The difference between this and 100 is an estimation of overstory density in percent.

Units are housed in a 3"H x 3"W x 1"D walnut case with operating instructions permanently affixed to the lid. A leveling bubble is also included for accurate positioning.

The readings from the Convex Densiometer represent a larger sample area than those of the Concave Densiometer.