Location: Delta Water Management Research Unit
Title: A retrospective review of cotton irrigation on a production farm in the Mid-South Authors
Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 15, 2014
Publication Date: N/A
Interpretive Summary: rrigation plays an important role in producing consistent and reliable cotton yields in the Mid-South. Of the approximately 600,000 acres of cotton planted in 2007 in Arkansas, over 90% was irrigated. Most cotton acreage is irrigated from the alluvial aquifer, which is being used at an unsustainable rate resulting in cones of depression and increased pumping costs. A retrospective review of irrigation practices from 2005-2012 from a cotton farm in Mississippi County, Arkansas is presented. Findings show there is a yield benefit from irrigation and guidelines regarding when to stop irrigation in the late summer were followed four of the five study years.
Technical Abstract: Arkansas ranks third in cotton production in the US. Irrigation plays an important role in producing more consistent and reliable yields in the region. Of the approximately 1.8 million ha (4.5 million ac) of irrigated agricultural land in Arkansas in 2007, over 11.6% was in cotton. Most cotton acreage is irrigated from the alluvial aquifer, which is being used at an unsustainable rate resulting in groundwater cones of depression and increasing production costs. Mississippi County has produced the majority of the cotton in the state for the past several decades, accounting for 20-25% of Arkansas production. A retrospective review of irrigation practices on over 2997 ha (7405 ac) from 2005-2012 on a cotton farm in Mississippi County, Arkansas is presented. The primary objective was to determine how well irrigation termination followed the eventual guidelines set forth for furrow-irrigated cotton and to compare the application of the guidelines to pivot-irrigated cotton. Additionally, water applied was quantified and the yield advantage from irrigation was analyzed. The data used for the analysis were from four sources: meteorological information collected from a nearby experimental station, irrigation logs from the producer, plant monitoring data, and yield monitoring. Findings indicate termination guidelines for furrow-irrigated fields were followed within two weeks for seven of the eight study years. Termination in pivot-irrigated fields was consistently later than furrow by an average of 8 days during the study period. Average water applied at the study site ranged from 602 to 770 mm (24 to 30 in) and 129 to 365 mm (5 to 14 in) at the furrow- and pivot-irrigated fields, respectively. The lint yield gain due to irrigation water applied at six fields studied was an average of 0.750 and 1.367 kg ha-1 mm-1 (17 and 31 lb acre-1 inch-1) and a maximum of 1.411 and 1.852 kg ha-1 mm-1 (32 and 42 lb acre-1 inch-1), in 2011 and 2012, respectively.