New Kinds of Systematic Designs for Spacing Experiments

Systematic designs for spacing experiments are developed having the properties that (i) the grid of plant positions is locally approximately rectangular, (ii) the two sets of curves defining the grid are either straight lines or arcs of concentric circles, and (iii) that the contours of equal area and of equal rectangularity of arrangement (length/breadth) are either straight lines or arcs of concentric circles, and the two sets are not coincident. 2. Five designs, four based on polar co-ordinates and one on a rectangular grid, are described and formulae given to enable plans to be constructed for field use. 3. Possible methods of analysis for the designs are discussed, and also the extent of their possible usefulness.