Factor levels for density comparisons in the split-block spacing design
The split-block spacing design is a compact test of the effects of within-row and between-row spacings. But the sometimes awkward analysis of density (i.e., trees/ha) effects may deter use of the design. The analysis is simpler if the row spacings are chosen to obtain a balanced set of equally spaced density and rectangularity treatments. A spacing study in poplar (Populus spp.) illustrates the approach.