Tips For Using FullStop™
Four Things You Need To Know
1. Resetting The Indicator
Water is 'sucked out' of the detector after irrigation by the soil around it. You must reset the detector after the indicator pops up by pushing the red indicator gently down to release the mangnetic latch. If the indicator immediately pops up again, it means that the soil is still very wet.
2. Indicator Up Means A Strong Front Has Moved Past The Detector
A wetting front will always move deeper than the detector after the indicator pops up. If the soil below the detector is dry, the wetting front will only move a short distance further. If the soil below the detector is wet, the wetting front can move a long way past the detector after the indicator pops up. Therefore it is important not to place detectors too deep, particularly for sprinkler irrrigation.
3. Effect Of Soil Disturbance
The soil structure is disturbed during installation of the detectors. This is not a problem for installation into ploughed soil. In the case of perennial crops the soil will need to settle and the roots grow back into the disturbed zone before the detector will give reliable information.
4. How Many FullStops™ Do You Need?
At least two pairs of detectors are needed in a field, because irrigation is usually not uniform and soil properties and crop growth also vary. Some irrigation systems like microjects tend to have large variability over small distances. Uniformity of wetting patterns should be measured and detectors place in 'wetter' and 'drier' spots to give an indication of variabilit in a wetting front depths.
Improving Irrigation Practice
When starting out, we recommend you continue to irrigate according to your normal practice while you get a 'feel' for how the detectors are responding. Then compare your normal practice to what the FullStop™ show you as summarized in the table below.
Once you have developed some confidence in the way the detectors are working, you are ready to learn how irrigation, nutrient and salt management can be improved. Change your water use practice at the rate at which you are comfortable, taking into account the growth and/or yield response of the plants. Note that it is not necessary to get the desired detector response after every irrigation - the general trends are more important.