Overview UK Burley Curing Advisory

http://weather.uky.edu/burley_curing.html

The Burley Curing Advisory has been developed to provide burley producers and related personnel with timely guidance on curing management procedures. The Advisory uses real-time data from the KyMesonetSystem and NOAA weather forecasting to provide the timely guidance on-line for speedy access by smart phones and computers. The KyMesonet system has weather stations in over 60 of Kentucky's counties, thus giving much local data for the Advisory that was not available for such a timely Advisory just a few years ago.

The electronic Burley Curing Advisory is based on numerous scientific curing studies over the past 70 years and the many years of experience and recent development work by Emeriti faculty Drs George Duncan and Linus Walton of the University of Kentucky College of Agriculture, BAE Dept., combined with the expertise and facilities of Mr. Tom Priddy and Dr. Wanhong Wang of the Ag Weather Center to create the on-line Advisory.

The Burley Curing Advisory uses the average temperature, relative humidity and wind speed data of the past 24 to 48 hours to assess the suitability of the past weather for curing burley in typical air-cure facilities and shows a brief message stating this condition.

Forecast data for the future 12 to 24 hours is used to assess the status of future curing conditions and show a brief statement to OPEN or CLOSE ventilators to favorably affect the curing environment.

Extended periods of very high relative humidity will trigger the Advisory to show EMERGENCY DRYING Needed. The use of fans in the facility is an alternative source of increased air movement and improved drying potential.

During some periods of high humidity, the Advisory may prompt to OPEN Vents when the cure is in the first two weeks or CLOSE Vents when the cure is in 3^rd week & later.

Conversely, extended periods of extremely dry weather conditions will trigger a prompt to CLOSE VENTS and ADD MOISTURE, which can be done by wetting the facility floor, walls or through special misting or sprinkler nozzles, or other humidity increasing methods.

A forecast of future 'cool' weather will trigger a prompt to CLOSE VENTS as this will help retain moisture as cool weather generally provides dry air which can prematurely desiccate the lamina and set off-colors. Curing chemistry is greatly slowed by the lower temperatures and the tobacco must be preserved until warm temperatures return (if likely) for better curing chemistry.

The listed average wind speeds give an indication of the potential air movement through ventilators to affect the inside curing environment.

Obviously, the Advisory cannot predict actual conditions within tobacco of a facility due to varying facility features, ventilator effectiveness, and packing of tobacco. Relative humidity instruments are recommended to give past and ongoing readings of relative humidity within the tobacco mass to indicate the condition of the tobacco relative to the external weather conditions shown by the Advisory and manage ventilators and fans, if used, accordingly.

This Advisory is applicable for the first 5-6 weeks of air-curing mature harvested burley plants initially housed without free moisture (wetness) or mud on the leaves, spaced 5-7 inches or more apart hanging in well ventilated air-cure facilities with operable ventilator panels during leaf yellowing and browning stages.

After all yellow color has been transformed from the leaves, lamina and stem drying conditions should continue and time of RH greater than 75-80% within the tobacco minimized until bulking and stripping occur.

Any person using this Advisory does so at his/her own risk.

Publications describing burley curing technology and management, selection and use of relative humidity instrumentation, installation and use of fans in typical barns and several past curing studies are posted on the web site: https://burleytobaccoextension.ca.uky.edu/

Questions or comments on this Advisory may be addressed to Bob Pearce (rpearce@uky.edu) or Matt Dixon (matt.dixon@uky.edu).

Updated : 7-1-24