=+15.23 gas-ex of Conifer Needles with Glass Beads for Determination of Leaf Surface Area” (Forest Science [1980]: 29–32)

included an analysis of dry matter per unit surface area

(mg/cm3

) for trees raised under three different growing conditions. Let m1

, m2

, and m3 represent the true mean dry matter per unit surface area for the growing conditions 1,