We’ve come full circle finishing one round of irrigation and getting straight into the next, starting back at the first field irrigated and slowly working our way back through. We’re currently running three fields at a time which is about the maximum we can run at a time before the water gets too hard to manage and levels drop to much or rise to much and blow the banks like we did early yesterday morning.
There are a couple of ways to tell when the crop needs watering the main one is to use a moisture probe, the moisture probe is a box that is placed over a tube going down into the soil, it then emits a small amount of radiation and works out were the moisture level is, it is then plugged into a computer which does up a graph showing the water level and daily usage as well as how many days until it needs to be watered. This is the most accurate way to measure the level and is done regularly, often daily by the agronomist. The other way is to do it by sight looking for visual clues such as wilting and drooping leaves, its not as accurate we only use it to decide which field to start first if the probe readings are similar.
We use furrow irrigation its the most popular type of irrigation compared to other methods such as overhead, drip or bank less channel, we find its the most efficient way of getting best yield for water used. Furrow irrigation involves hand primed siphons (2-3 metre sections of 2 or 3 inch poly pipe) drawing water from the head ditch and into the furrows that run down the field, when the water gets to end of the field it is collected in the tail drain and drained away to a channel were it is pumped back up into the head ditch so nothing is wasted.
If their is anything else you want to know just ask in the comments and sorry if the photos are getting a bit repetitive but their is only so much I can photograph while working night shift.