Status of Variable-Rate Irrigation in the Southeast

Abstract

Variable rate irrigation (VRI) technology works by applying irrigation water based on specific water needs of individual management zones, rather than applying a uniform rate across an entire field. By optimizing water application, the use of VRI can potentially save millions of gallons of irrigation water while increasing both crop yield and quality. The VRI system, developed at the University of Georgia, was commercialized by Farmscan in the fall of 2004. Hobbs and Holder, LLC, the US dealer for Farmscan, has to date installed 32 VRI systems onto a variety of center pivot systems from various manufacturers (i.e., Valley, Reinke, Zimmatic, and Gifford-Hill). These installations have taken place in Georgia, South Carolina, Florida, and Arkansas. Reasons for farmer interest in adopting VRI have ranged from environmental stewardship, conservation, economics, and productivity. Current VRI systems are installed on farms that grow traditional row crops (peanuts, cotton, and corn) as well as less conventional crops (i.e., turf). For these 32 installations, the average pivot size was 1463 ft (155 acres) with 138 of those acres cropped and 17 acres non-cropped. Although the average installation cost was $21,379.00, because cost-share assistance was provided through federally funded grants the average cost to the farmer has been only $5,345, or $34 per acre.