Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 14, 2004
Publication Date: February 2, 2005
Citation: Sassenrath, G.F., Adams, E.R., Williford, J.R. 2005. Rapid sampling system for determination of cotton fiber quality spatial variability. Applied Engineering in Agriculture. 21(1):9-14. Interpretive Summary: The introduction of accurate, reliable cotton yield monitors has increased the value of spatial information pertaining to cotton growth and yield potential, and contributed to the development and incorporation of site-specific methodologies in cotton production. While knowledge of the spatial variability of cotton yield is important for developing optimal profitability, cotton quality also contributes to the net return. Cotton fiber is graded for a variety of properties based on physiological maturity. The price of the cotton is then derived from the measured fiber quality. Variability in cotton yield contributes substantially to the divergence of profitability from various regions within production fields. Variability in fiber quality parameters will contribute additional alterations in the profitability of field regions. Currently, the determination of spatial patterns of fiber quality is performed by hand-harvesting areas of research or production fields. While this provides some measure of the degree and extent of variability in fiber properties, hand harvesting is tedious, time consuming, and error prone. Hand-harvested cotton displays distinct differences in fiber properties from that harvested mechanically. Moreover, the time and labor commitment to adequately sample a large production field makes hand harvesting untenable for rapid and accurate determination of spatial patterns of fiber quality. Our research examines the spatial variability of fiber quality and quantity, with an end to delineating the underlying parameters contributing to that variability. To adequately address the variability of fiber production, we needed an accurate, rapid method of spatially sampling cotton lint. Moreover, to assure similarity between our measures of cotton fiber properties and those received by the producer or the gin, we needed a method of sampling the cotton after it had been mechanically harvested. We developed a sampling system that attaches to the transfer chute of the cotton harvester. The sampling system diverts the harvested cotton from the picker basket to a small sampling bag. The sampling system allows rapid subsampling of the harvested cotton in a spatially registered location. The sampling system has been tested for two harvest seasons, and found to give a reasonable approximation to spatial variability of the cotton fiber.
Technical Abstract: Advances in engineering technologies have contributed to our knowledge of spatial variability of cotton yield through development of the cotton yield monitor. The cotton yield monitor allows continuous sampling of the amount of cotton lint harvested from an area as the cotton picker moves through the field. For cotton, the price paid for the cotton lint is determined by the quality of the harvested fiber, measured by the USDA-AMS classing office. Various factors can contribute to fiber quality, reducing the overall value of the lint, and the subsequent price received. To date, no method of automated spatially-registered collection of cotton lint has been available to researchers interested in understanding factors controlling cotton lint quality. This study was undertaken to develop a sampling apparatus that would install on a commercial cotton picker, and allow spatially registered cotton samples to be taken for determination of lint quality. The cotton sampler works well, and attaches simply to the cotton chute.