MISSISSIPPI COTTON YIELD MONITOR: THREE YEARS OF FIELD-TEST RESULTS

Abstract

The Mississippi cotton yield monitor, which is based on an optical cotton-flow sensor comprised of emitters anddetectors in one unit that can be affixed to only one side of a pneumatic duct, has been under development at Mississippi StateUniversity since 1999. One prototype of the yield monitor was field tested that year in Mississippi. In 2000, three prototypeswere constructed and field tested in Texas, Georgia, and Mississippi on about 530 ha (1300 acre) of cotton. Different varietieswith large yield variations were harvested. In the Texas test, average absolute errors for two fields were 5.9% and 5.4%.Results from the Georgia test indicated an average absolute error of 5.7%. System reliability was tested in Mississippi on about445 of the total 530 ha (1100 out of 1300 acre) of cotton. Based on the 2000 results, a new version of the Mississippi cottonyield monitor was designed to include anti-stray-light and temperature-stabilization features. Five prototypes of the newversion were fabricated and field tested in 2001 on three cotton pickers and two cotton strippers at five locations in Georgia,Texas, and Mississippi. A total of 1230 ha (3000 acre) of cotton was harvested with the yield monitors from September toDecember of 2001. Results indicated that the average absolute errors of the system were 3.7% and 4.9% in two fields wheresystem accuracy was evaluated load by load. Considering all three years data, the average measurement error of theMississippi cotton yield monitor was less than 5%, and the latest prototype is improved over previous versions. Cotton yieldmaps have been created with data from all the field tests, and the maps realistically exhibit yield variations within fields, basedon the expectations of experienced producers and consultants. The tests also indicated that the system was reliable and easyto install, operate, and maintain.