Submitted to: Transactions of the ASABE
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/15/2005
Publication Date: 6/14/2006
Citation: Funk, P.A., Armijo, C.B., Brashears, A.D., McAlister III, D.D., Showler, A., Fletcher, R.S. 2006. COTTON HARVEST PREPARATION USING THERMAL ENERGY. Transactions of the ASABE. Vol 49(3): 617-622. (2006). Interpretive Summary: Replicated plots in eight fields in three states were treated with conventional chemical defoliants and the experiment, thermal energy. Cotton was harvested after two days, after two weeks, and later to compare yield and fiber quality. This novel tool for insect control and harvest preparation allows producers to pick or strip within 48 hours of treatment. Fiber value and yield were not significantly different for the three treatments (chemical, thermal and no defoliation). Harvesting early (within 48 hours) can result in slightly lower yields and would therefore be desired to avoid greater losses such as from a hurricane. In all cases, the complete leaf desiccation resulting from thermal treatment protects cotton from late season insect pests. Silverleaf Whiteflies and Cotton Aphids have no food supply and therefore can not make the cotton sticky by excreting sugars on open bolls. Preventing sticky cotton is a vital part of assuring continued demand for American fiber.
Technical Abstract: Managing cotton for mechanical harvest requires the use of chemicals restricted in organic production. Thermal defoliation is an effective alternative resulting in rapid leaf desiccation. Field trials were needed to determine the best timing for thermal treatment and harvest. Crop termination using thermal energy was compared to conventional defoliation in a variety of locations, cultivars and production practices over two seasons. Field trial results indicate that harvest can commence as soon as 48 hours after thermal treatment. Trials showed that the lint value of thermally treated cotton was the same as or higher than the value of lint from chemically defoliated cotton. Fuel consumption, other fiber quality measures and ginning and spinning test data are presented for eight trials in three states. Organic producers can prepare for mechanical harvest, manage late season insects and actually have more control over harvest timing than conventional producers.