Figure 3: (a) Four trees each of basal area 2500 cm² in an area of 625 m². A fixed-area plot of 625 m² or an angle count with BAF = 4 will agree that the stand density is 16 m²/ha. (b) A stand of 1018 m², including the same four trees as (a) plus one tree of basal area 5027 cm² and two of 78.5 cm² each. The true stand density is now 14.9 m²/ha, but the fixed-area plot sees 16 m²/ha and the angle count 20 m²/ha.