Sensors Monitor Tensions in Transpiration Streams of Trees

Science  02 Aug 1968:
Vol. 161, Issue 3840, pp. 484-485
DOI: 10.1126/science.161.3840.484


Resistance of implanted sensors fluctuated predictably with uptakes and loss of water by plants, and correlated positively with coincidental measurements of leaf-water potential when transpiration was minimized. Preliminary results indicate that transmission of change in tension may be almost instantaneous, regardless of transpirational flow rates. Rates of relaxation of tension were very rapid after precipitation, but only after water had percolated to root surfaces.