Fig. 4. Two consecutive examples of a 4-h reaction time between following a manual water addition: A sharp increase in _perlite (Probe 10, 200 mm) and _stem by probes: 3, 17, and 18 (70-, 48-, and 29-mm long rods, respectively), during DOY 214. The right facing arrows are pointing to the timing of the manual water additions (214.33 and 214.58) and the left arrows face the dotted vertical lines indicating the start of stem probes response.