Nelder plot (Nelder 1962) is an experimental design for testing a multiple tree spacings in a single plot. The shape of plot is circular with some number of concentric wheels or arcs radiating outward and the spokes connecting the center. The intersections of spokes and arcs are the tree positions. The tree position on different wheels represent a different the tree spacing distance or tree density. This design eliminates the need for separate experimental plots for each tree density. The difficulties with Nelder plot design is their uncommon layout and complex parameterization (Parrott et al. 2012). This computer-aided tool for designing the Nelder plot can be very useful for the practical implementation of this experimental design.\r\n\r\nReferences\r\nNelder JA (1962) New kinds of systematic designs for spacing experiments. Biometrics 283–307\r\nParrott DL, Brinks JS, Lhotka JM (2012) Designing Nelder wheel plots for tree density experiments. New Forests 43:245–254.