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Dear Bruce: Following my preliminary contact with you, I can see some benefit in presenting past and current information regarding the Capacitance Soil Moisture Sensor also known in some places as 'Flori' and distributed by "Netafim" or its representatives. History: Since 1991, and for three intensive years, the Agricultural Research Organization, (ARO), Ministry of Agriculture, State of Israel (through me), and a small yet energetic engineering group (called Silora) have cooperated to build and develop the above sensor. FOR THOSE IN A HURRY I'LL MENTION RIGHT AWAY THAT A FULL SCIENTIFIC REPORT WAS PRESENTED IN THE AUS. J. OF SOIL RES. 1996, 34:361-368, ENTITLED: "AN IMPROVED CAPACITANCE SENSOR FOR IN-SITU MONITORING OF SOIL MOISTURE." The idea was to build a cheap, accurate soil moisture sensor, for gardening and agricultural applications, that will be free from texture and salinity effects. In order to stay cheap we had to avoid the two classical solutions: High frequencies (around 150 MHZ) or short time measurement (like, for example in the TDR technology). A combination of a little luck, and a lot of motivation, hard work, and patience resulted in a prototype that satisfied our demands, under both lab and field trials. On 1994, due to financial disagreements we splitted. Present Status: Following changes introduced between the R&D and production phases there was a negative progress with respect to the sensor's sensitivity. The current version is disturbingly dependent on soil texture, salinity and even temperature. I speculate that this originated from the lack of a full understanding of the principle of operation by the production team. "Netafim" is fully aware of the situation and tries her best to overcome this obstacles: They hired people are cooperating with farmers dwelling in different regions and soil textures. They supply the sensors and additional control means (usually tensiometers) to better understand what has to be fixed. Summary: The presently (industrial) version of the Capacitance Sensor may questionably have a single application option: A yes/no device for controlling a valve in the garden; Still, it will work empirically, relatively, extremely locally, and will still dependent on temperature (which means that seasonal adjustments may probably be necessary). As for my efforts: After three years of additional work while looking for funds (inside and outside the local administration), I temporarily gave up until I get generous funds to enable the expensive next phases. If the SOWAC subscribers have further questions, they can direct them to me or you and I'll answer, if I can sincerely, Arie Nadler Dept of Soil Physical Chemistry Soil and Water Inst, ARO POB, 6 Bet Dagan Israel, 50250 E Mail: vwnad@volcani.agri.gov.il