Best Management Practices Following A Freeze In Sugarcane
By Kenneth Gravois and Herman Waguespack
LSU AgCenter
A severe freeze is forecasted beginning on December 23, 2022, and for a series of nights afterwards. At the time of the December 23rd freeze, the industry will be about 83% harvested. All sugarcane remaining in the industry will be damaged to some extent. Every freeze event is different and forecasting the extent that harvest can be completed is impossible. Deterioration following a freeze is temperature dependent – higher temperatures will increase deterioration and lower temperatures will reduce deterioration.
Stalks have peaked in sugar content and will begin to slowly dehydrate. Any stalk damage, whether by freezing temperatures, borer injury, growth cracks, brittleness, harvester, or mill yard equipment, will allow bacteria to enter the stalk to begin the deterioration process. The goal is to reduce the impact of deterioration by following the guidelines below.
The advanced stage of harvest and the severity of the forecasted freeze will limit the impact of some guidelines.
It is important that growers and processors work together to minimize the impact of this freeze.
Do not panic. The industry has experienced freezes in past years and successfully completed the harvest. There will be losses - to what extent is unknown.
Varieties make a difference when temperatures are above 22 F. However, temperatures below 22 F kill all above ground parts of commercial varieties. L 11-183, L 12-201, Ho 12-615 and HoCP 14-885 have poor cold tolerance and should be harvested first. Intermediate varieties L 01-299, HoCP 09-804, Ho 13-739, L 14-267, L 15-306 and HoL 15-508 may last longer. HoCP96-540, L 01-283 and HoCP 04-838 are varieties with the best cold tolerance.
Survey on a field-by-field basis. A harvest schedule should be made based on a field-by-field survey. To survey for damage, cut stalks of cane and split them lengthwise. Look for discoloration and water-soaked conditions. After an initial survey is made and these general recommendations are considered, a harvest schedule should be prepared. Follow-up surveys should be made to track deterioration and alterations should be made to the original schedule to cut fields, which are in most need of quick harvest.
Areas of higher elevation tend to be warmer. A few degrees of temperature makes a difference during a freeze event, as much as 2 – 3 degrees F on some farms based on elevation. Areas on the farm at higher elevation can have less freeze damage. Rivers, bayous, lakes, and tree lines can offer some freeze protection.
Standing cane vs. down cane. Within the same variety, standing cane has less freeze damage than cane that is lodged.
Topping and cleaning cane. Keep a knife handy to split stalks to monitor freeze damage. With straighter cane this year, growers have a better opportunity to top the cane to the area where little freeze damage has occurred. For combines, run the fans aggressively and keep good blades in the choppers. It is better to leave a small amount of cane in the field than to leave the whole field behind later.
What about burning? Burning can help improve cane quality if done correctly; burning can contribute to poor quality cane if done incorrectly. Burn only what you will harvest for that day’s quota.
Do not burn when night temperatures are greater than 50 F.
Burning will improve combine capacity and decrease trash at the mill.
Burned cane not processed within 18-24 hours will contribute to dextran problems.
If possible, make firebreaks to prevent accidental spread of fire in large blocks of cane. Many fields are large and cannot be burned for only single day quotas. Do not burn these fields because mills will have very little flexibility with quotas.
Burn only when conditions are conducive as described in the certified prescribed burn manager program.
Stacks of harvested cane at the farm should be managed to allow for processing in 18-24 hours. Do not stack overnight – consider stacking cane much like an overnight load.
Overnight loads. Overnight or sleeper loads should be stopped. Do not pre-load on days off.