Editing Irrigation (section)

==== Center pivot ====
{{Main|Center pivot irrigation}}
[[File:Center Pivot.jpg|thumb|A small center pivot system from beginning to end]]
[[File:Nelson A3000 Accelerator.png|thumb|Rotator style pivot applicator sprinkler]]
[[File:PivotWithDrops.JPG|thumb|Center pivot with drop sprinklers]]
[[File:WheelLineIrrigation.JPG|thumb|Wheel line irrigation system in [[Idaho]], US, 2001]]
[[File:Crop Triangle South Africa.jpg|alt=Center pivot irrigation|thumb|[[Center pivot irrigation]]]]
Center pivot irrigation is a form of sprinkler irrigation utilising several segments of pipe (usually galvanized steel or aluminium) joined and supported by [[truss]]es, mounted on wheeled towers with sprinklers positioned along its length.<ref>{{cite web
| url= http://www.thefencepost.com/article/20100525/NEWS/100529954
| title= Center pivot irrigation revolutionizes agriculture
| work= The Fence Post Magazine
| date= May 25, 2010
| access-date= June 6, 2012
| author= Mader, Shelli
| archive-url= https://web.archive.org/web/20160908232107/http://www.thefencepost.com/article/20100525/NEWS/100529954
| archive-date= September 8, 2016
| url-status= dead
}}</ref>
The system moves in a circular pattern and is fed with water from the pivot point at the center of the arc. These systems are found and used in all parts of the world and allow irrigation of all types of terrain. Newer systems have drop sprinkler heads as shown in the image that follows.

{{As of | 2017}} most center pivot systems have drops hanging from a U-shaped pipe attached at the top of the pipe with sprinkler heads that are positioned a few feet (at most) above the crop, thus limiting evaporative losses. Drops can also be used with drag hoses or bubblers that deposit the water directly on the ground between crops. Crops are often planted in a circle to conform to the center pivot. This type of system is known as LEPA (Low Energy Precision Application). Originally, most center pivots were water-powered. These were replaced by hydraulic systems (''[[T-L Irrigation]]'') and electric-motor-driven systems (Reinke, Valley, Zimmatic). Many modern pivots feature [[GPS]] devices.<ref>{{Cite web|url=https://www.agriculture.com/machinery/irrigation-equipment/gps-swing-arms-prove-their-worth|title=GPS SWING ARMS PROVE THEIR WORTH|last=Gaines|first=Tharran|date=January 7, 2017|website=Successful Farming|access-date=February 1, 2018}}</ref>