|Richard jr, Edward|
Submitted to: Sugar Bulletin
Publication Type: Trade journal
Publication Acceptance Date: 4/11/2008
Publication Date: 5/1/2008
Citation: Viator, R.P., Salassi, M.E., Johnson, R.M., Richard Jr, E.P. 2008. Cultivation needed for profitable stubble crops. Sugar Bulletin. 86(7):22-23. Interpretive Summary:
Technical Abstract: The rise in fuel prices is forcing sugarcane producers to reduce tillage. Two conservation tillage experiments began in 2004 to compare conventional and no-till systems. This study utilized LCP 85-384 on a light soil and L 97-128 on a heavy soil, and tillage treatments consisted of either no-tillage or conventional tillage. We evaluated these tillage treatments in plant-cane, first, and second stubble. We looked at single years and multiple years of no-till to determine both the short and long term impacts. Sugarcane was mechanically harvested in November 2005-2007 with a chopper harvester and a weigh wagon equipped with electronic load cells, and random billeted-cane samples were analyzed for sucrose content. Economic analysis was conducted with information from the LSU Ag Center 2008 Projected Sugarcane Production Costs and Returns, which estimates that the variable cost of cultivation is $4.91/A using $2.90/ gallon for fuel. The data from both soil types and varieties showed similar results, so all the data was averaged across both experiments. In plant cane the no-till plots produced 300 lbs sugar/A more than conventional tillage. If one considers the total variable cost of $19.64 per acre for four cultivations and assumes $0.10/ lb of sugar paid to the grower (taking out rent and milling cost), no-till increased net returns by $49.64/A. In contrast to plant cane, first- and second-stubble crops showed a positive response to tillage. For both stubble crops, the no-till treatment decreased yields by 490 and 400 lbs/A, which equates to a decreased profit of $29.36/A and $20.36/A, respectively. When one considers the long term effects of tillage, conventional tillage is definitely needed for stubble crops. When cane was no-tilled for two consecutive years as plant-cane and first stubble, sugar yields and profits decreased by 570 lbs/A and $37.36/A compared to the conventional system. When cane was no-tilled for two consecutive years as first and second stubble, sugar yields and profits decreased by 460 lbs/A and $26.36/A compared to the conventional system. To conclude, one may consider a no-till system in plant cane where bermudagrass is not a problem. In contrast to plant cane, stubble crops responded favorably to conventional tillage. Yield losses with no-till were greater if one used this system for two consecutive years. Future research will focus on the number of cultivations needed within a season to maximize both short and long-term profits.