Cotton Harvesting

Authors: Wanjura, John

Submitted to: International Cotton Conference
Publication Type: Other
Publication Acceptance Date: 8/3/2016
Publication Date: N/A
Citation: N/A

Interpretive Summary: Cotton pickers and strippers are the two mechanical harvesting systems available for use in the US. Strippers were developed as a cost effective alternative to pickers for harvesting relatively low yielding cotton with closed or "storm resistant" boll types. Strippers use a non-selective harvesting mechanism which removes essentially all of the material from the plants during harvest. Pickers use a more selective harvesting mechanism which removes seed cotton only from well opened bolls with minimal amounts of undesirable vegetative material. Cotton strippers require that the plants be in a dry, desiccated condition at the time of harvest so that the material can be easily snapped off of the plants. Thus, stripping is better suited to arid regions of the US where harvest time relative humidity is low enough to facilitate dry crop conditions. Harvesting efficiency is higher for strippers than pickers and often results in higher seed cotton and lint yields for stripper harvested cotton. However, the portion of seed cotton usually left in the field by cotton pickers is generally low quality, thus, average fiber quality levels are generally improved for picker harvested cotton. A study conducted in the Southern High Plains region discussed during this presentation found that regardless of productivity gains and improved fiber quality for picker based harvesting systems, stripper based harvesting systems had higher net economic return per land area when considering all harvesting and ginning expenses.

Technical Abstract: Cotton harvesting is performed in the US using either a spindle picker or brush-roll stripper. This presentation discusses the environmental, economic, geographic, and cultivar specific reasons behind a grower's choice to use either machine. The development of each machine system was discussed. A basic description of how the harvesting units function on each machine was presented as well as an operational description of ancillary equipment used onboard the harvesters to convey, clean, and package seed cotton for infield storage. Key setup and mainteanance items were reviewed from the standpoint of maximizing harvesting efficiency, productivity, and fiber qualtiy. Lastly, a multi-year study on comparing picker and stripper based harvest systems under commercial conditions was presented. The findings of this study conducted in the Southern High Plains region indicated improved fiber qualtiy for picker based systems but higher harvesting efficiency and lower harvesting costs associated with the stripper systems resulted in a higher overall net revenue for stripper based harvesting systems.