... LondonMilburn J.A. & Johnson R.P.C. (1966) Theconduction of sap. 11. Detection of vibrationsproduced by sap cavitations in Ricinus stem.Planta 69, 43-52Sandford A.P. ... envi-ronment or in field conditions withoutbackground interference.Materials and Methods Using a circuit design based on that by Sand-ford and Grace (1984), acoustic emissions ... 1094-1099The use of ultrasonic detectors for water stress determination in fruit treesH.G.JonesK.H. Higgs2tural Research, WA. Bergamini3urne, Warwick, U.K.,1 Institute of Horticultural...