Fig. 2. A schematic representation of the position of nodal roots on the primary stolon of plants of the four nodal rooting treatments following a common establishment procedure which provided all plants with two nodal root systems at the base of the plant. The phytomer numbering system is shown and the two treatment phases of the experiment are depicted. During phase 1, plants were either allowed to form nodal roots (+R) or were prevented from doing so (–R). In phase 2, +R plants of phase 1 were either permitted (+R) or prevented (+R–R) from continuing to form nodal roots, whereas –R plants of phase 1 were either permitted to form a nodal root system at the first phytomer to emerge in phase 2 and then prevented from forming further nodal roots (–R+1R), or prevented from forming nodal roots throughout (–R).