Cotton was produced in eight different row configurations ranging in width from 15 inch solid and skip row to 38 inch solid and skip row configurations at the North Mississippi Research and Extension Center, Verona, MS, and at private farms in Falkner, MS, Clarksdale, MS and Greenwood, MS in 2005.

Two John Deere Pro 12 VRS spindle picker row units were mounted on a John Deere 9960, four row picker chassis and used to harvest the plots. The harvester operation was observed, yield and losses measured, samples ginned and lint sampled for AFIS and HVI quality determinations. Data from 2005 and a summary of all locations and years including yields, quality and predicted harvest system costs will be presented.

Stalk losses were greater in the 15 inch row configurations at Falkner and Verona in 2004 and ranged between 2.1% and 3.5% with a slight variation in loss amounts by location. Ground losses were influenced by pre harvest weather events at Verona and Falkner. In 2004 ground losses ranged from a location average low of 2.6% at Clarksdale where no rainfall occurred between boll opening and harvest to 7.9% at Verona following a heavy rain on September 19 and 9.6% at Falkner, where plots were exposed to several heavy rain events during October. No meaningful fiber quality differences were found between treatments in 2003 or 2004. In 2004, all treatments produced equal fiber qualities for each location as measured by HVI; however, color, strength and length were influenced by location.

The harvest simulation model, XLCOTSIM, was used to predict the impact of row spacing and machine performance on net revenue after harvest costs were deducted. Yield, fiber quality, harvest losses, and estimates of machinery costs were used in the model for each row pattern. Narrow row treatments produced the greater net revenue after harvest cost with the 15 inch 2 X 1skip rows producing $530/ac and the 38 inch 2 X 1 skip row producing a net revenue of $442/ac. The trend was for net revenue after harvest expenses to decrease as row width increased for all locations and for both years with the exception of the Clarksdale location where yield differences were not as great.