The ratio between the effective
root areas in the two- and one-side systems was about 1.9 for many
watering distances (Fig. 4b), whereas that between shoots heights
(Fig. 2a) or plant weights (Fig. 6b) was about 1.2. Root growth and
degradation during the 76 days of the experiment resulted in movement
of the centers of the root zones towards the water source, in
most cases.