We traveled to the site with Armel Morlet from the company Valmont® Irrigation. The pivot located in the middle is covered in rust: “The water in this part of the Landes has a high iron content, which gives the pivots a rusty colour, particularly when the sprinklers are located above the spans,” he explained.
We returned to the car and drove on to a second site, to a smaller-sized field. At this location, the field is irrigated by one large single Otech pivot with 13 spans. We could see a Valley GPS Ready control panel and an antenna on the pivot, which sends information about the pivot to the farm, by radio. We returned once again to the car and this time we drove on to a circular 98-hectare field irrigated by a single Valley PolySpan® pivot of 10 spans. This pivot has a tank, which itself is supplied by six or seven small pumps. The building located near the tank acts as a control room for managing all the pumps used to fill the tank/reserve, as well as the supply pump.
This type of installation with a tank can be used with all the large pivots on the farm. As far as the small pivots are concerned, they are directly supplied by the borehole pumps. The choice of the Landes region for growing maize, which requires a lot of water, does not pose any great risk; in fact, there is an abundance of water resources. Below the sandy soils of the Landes region there is a plio-quaternary aquifer, with a high iron content, which allows the farmers to have permanent access to a plentiful supply of water.
45 pivots Linked to the Farm by Radio
We then went to the farmhouse where we were met by the owner’s son, Romain Nérault, as well as his assistant, Eric Gilbert. Originally, this was divided into two farms, the Lucate and Courlouze properties, which explains its present size of 1,460 hectares.
|From left, Romain Nérault, Armel Morlet and Eric Gilbert|
|The pivot can be set in motion from a standard computer |
or a mobile computer system,
and it is possible take action remotely.
Furthermore, 10 or so hectares are irrigated with full cover (sprinkler) systems. This technique allows for the irrigation of the zones that the pivots cannot manage to reach; in fact, with the pivots irrigating in a circle, there are often blind spots, which are not irrigated. Finally, a small “L-shaped” field is irrigated with subsurface drip irrigation. “This is a kind of test”, explained Romain. “In fact, certain complex fields are difficult to irrigate with pivots or linear moves. The aim is also to reduce the amount of water applied per hectare and the consumption of KW/h per hectare.”
When we click on a pivot, the control box appears on the screen, giving the pressure, position in degrees and forward speed of the pivot. The pivot can be set in motion from a standard computer or from a mobile computer system and it is possible to take action remotely.
Read the last section of the article, How the Irrigation Season Unfolds.