Author
|
Submitted to: Crop Management at www.cropmanagement.org
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/7/2007 Publication Date: 1/18/2008 Citation: Sorensen, R.B., Lamb, M.C. 2008. Corn and Cotton Yield with Two Surface Drip Lateral Spacings. Crop Management at www.cropmanagement.org. DOI:10.1094/CM-2008-018-01-RS. Interpretive Summary: Surface drip irrigation laterals were spaced next to crop rows and in alternate row middles to document crop yield and partial economic returns compared with non-irrigated areas. A surface drip irrigation system was installed at two sites on a Faceville (Site 1) and a Greenville (Site 2) fine sandy loam with 1 to 3% slope, respectively. Drip tube laterals were spaced at 3 foot (adjacent a crop row) and at 6 feet (alternate crop row middles). Cotton and corn were planted on 3 ft row spacing. Corn was planted at a higher rate (31,000 seeds/ac) on the drip irrigated area and at a lower rate on the non-irrigated (19,000) area. Both drip tube orientations, 3 ft and 6ft, had the same corn yield (9394 lbs/ac; 168 bu/ac) compared with the non-irrigated areas (4950 lbs/ac; 88 bu/ac). Subtracting the cost of the corn seed and drip tubing from the two irrigated regimens showed that 3 ft lateral spacing had $63/ac less net revenue compared with non-irrigated ($219/ac). The 16 ft spaced laterals had $89/ac greater net revenue than the non-irrigated areas. Cotton lint yield averaged 1063 lbs/ac for 3 ft and 6 ft lateral spacing compared with the non-irrigated lint yield (541 lbs/ac). Cotton gross revenue at both sites averaged about $544/ac for both lateral orientations. Non-irrigated cotton revenue averaged over $272/ac. Subtracting the cost of the tubing resulted in net revenues of $278/ac and $440/ac for 3 ft and 6 ft lateral spacing, respectively. The 3 ft m lateral spacing may not be cost effective for either corn or cotton. Partial net return analysis shows that 6 ft lateral spacing had higher returns for both crops. Technical Abstract: Surface drip irrigation laterals were spaced next to crop rows (0.91 m) and in alternate row middles (1.83 m) to document crop yield and partial economic returns compared with non-irrigated areas. A surface drip irrigation system was installed at two sites on a Faceville (Site 1) and a Greenville (Site 2) fine sandy loam with 1 to 3% slope, respectively. Cotton and corn were planted on 0.91 m row spacing. Drip tube orientations, 0.91 and 1.83 m, had the same corn yield (10,555 kg/ha) compared with the non-irrigated areas (5,562 kg/ha). Subtracting the cost of corn seed and drip tubing from the two irrigated regimens show that 0.91 m lateral spacing had $140/ha less net revenue compared with non-irrigated ($484/ac). The 1.83 m spaced laterals had $196/ha greater net revenue than the non-irrigated areas. Cotton lint yield averaged 1194 kg/ha for 0.91 and 1.83 m lateral spacing compared with the non-irrigated lint yield (608 kg/ha). Cotton gross revenue at both sites averaged about $1200/ha for both lateral orientations. Non-irrigated cotton revenue averaged over $600/ha. Subtracting the cost of the tubing resulted in net revenues of $613 and $969 for 0.91 and 1.83 m lateral spacing, respectively. The 0.91 m lateral spacing may not be cost effective for either corn or cotton. Partial net return analysis shows that 1.83 m lateral spacing had higher returns for both crops. |
