NCC Comments on Ethephon

The NCC submitted comments to EPA on July 24 on the agency's proposed interim registration decision for Ethephon.

Published: July 26, 2017
Updated: July 26, 2017

July 24, 2017

Office of Pesticide Programs
Regulatory Public Docket (7502P)
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., NW Washington, DC 20460

RE: Docket ID Number EPA-HQ-OPP-2010-0098-0022, Registration Reviews: Ethephon

The National Cotton Council (NCC) appreciates 1) the opportunity to comment on the proposed interim registration decision for Ethephon and 2) that the Environmental Protection Agency (EPA) recognizes the value of the product for the cotton industry as a harvest aid.  The NCC strongly supports continued registration of this harvest aid product.

The NCC is the central organization of the United States cotton industry.  Its members include producers, ginners, cottonseed processors and merchandizers, merchants, cooperatives, warehousers and textile manufacturers.  A majority of the industry is concentrated in 17 cotton-producing states stretching from California to Virginia. U.S. cotton producers cultivate between 9 and 12 million acres of cotton with production averaging 12 to 18 million 480-lb bales annually. The downstream manufacturers of cotton apparel and home furnishings are located in virtually every state. Farms and businesses directly involved in the production, distribution and processing of cotton employ more than 125,000 workers and produce direct business revenue of more than $21 billion.  Annual cotton production is valued at more than $5.5 billion at the farm gate, the point at which the producer markets the crop.  Accounting for the ripple effect of cotton through the broader economy, direct and indirect employment surpasses 280,000 workers with economic activity of almost $100 billion. In addition to the cotton fiber, cottonseed products are used for livestock feed and cottonseed oil is used as an ingredient in food products as well as being a premium cooking oil.

The NCC has read the interim decision and appreciates EPA’s recognition that ethephon is used as a harvest aid in cotton.  The use of ethephon hastens the natural process of ethylene production at maturity.  The crop’s phenological time referred to as “cut out” basically means the cotton crop stopped its reproductive growth, stopped adding flowers, and is terminating its cycle.  Preparing for a clean and rapid harvest is critical to cotton’s fiber and seed value and quality.  The producer’s ability to complete harvest equipment operations prior to frost and wet environmental conditions impacts yield, quality, and value.  Ethephon, most often used in combination with other harvest aids, helps the plant form the appropriate abscission layer to drop leaves, and open mature bolls for harvest.  The preparation of cotton fields for harvest has often been termed a scientific art because of the multiple goals to be achieved from the harvest aids. 

Harvest aids accelerate the physiological process that induces or contributes to one of more of the following:

  • Boll Opening
  • Removal of mature leaves
  • Removal of immature leaves
  • Regrowth suppression or inhibition
  • Leaf desiccation (required for stripper harvest)
  • Desiccation of weeds

(Cotton Harvest Management: Use and Influence of Harvest Aids, ed. J. Supak and C. Snipes, The Cotton Foundation Reference Series Number 5, 2001)

The process described above should eliminate concern for pollinator studies as proposed because the plant has lost virtually all of its attractiveness to bees at this point.  Harvest aids are utilized to terminate the growth of the cotton plant, enhance senescence of leaves, and opening of bolls.  The timing for use coincides with the maturation of the cotton plant to the point it has bloomed out the top and growth has slowed due to the boll load.  The plant naturally begins to open bolls and produce ethylene to achieve senescence at the abscission zone.  Few, if any, flowers remain in the top of the plant as the plant shuts down and begins producing and maturing fruit.  The process can be influenced by weather and other environmental factors, therefore harvest aids are necessary to ensure uniformity of process and preparation for harvest equipment.  The harvest aids avoid weather events such as frost, rain, etc. that affect quality, leaf trash, and grade.  Their use, though, is at the termination of the crop and therefore should not require complete pollinator studies due to lack of a viable plant that is in an active flowering stage.

The NCC appreciates the ability to comment on the interim registration decision for Ethephon, and encourages EPA to complete the registration of this product which is important for maintaining the value and high quality of U.S. cotton.


Steve Hensley
Senior Scientist, Regulatory and Environmental Issues
National Cotton Council