|Richard Jr, Edward|
Submitted to: International Society of Sugar Cane Technologists Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/3/1998
Publication Date: N/A
Interpretive Summary: From 1993 to 1997, the percentage of Louisiana sugarcane harvested with a chopper harvester has increased from 0 to 50%. The switch from the soldier harvester system is being brought about by the development of high yielding, usually lodged, cultivars and by pending restrictions on burning. The effects of the blanket of leaf litter left on the field following the harvest of green cane with the chopper harvester was assessed. The blanket of leaf material provided some season-long suppression of weed development and some protection of sugarcane buds from freezing temperatures. However, the emergence and early development of the sugarcane crop was also suppressed by the blanket and ultimately sugar yields were reduced from 6 to 19%. Delaying removal of the blanket until early March to take advantage of the weed suppression and cold protection, did not overcome the suppressive effects on the crop with sugar yields being similar to the no removal treatment. With additional delays in removal, especially using removal treatments that injured emerged sugarcane shoots, a further reduction in sugar yield was obtained. Considering the sub-tropical climate of Louisiana, growers should remove chopper-harvester generated trash blankets at least by the conclusion of the harvest season to avoid potential yield reductions in subsequent ratoon crops.
Technical Abstract: Field experiments were conducted between 1993 and 1997 in commercial fields throughout the Louisiana sugarcane industry to evaluate effects of chopper-harvester generated green cane trash blankets (GCTB) on weed control and sugarcane development. Sugarcane development and ultimately cane and sugar yields were similar in five experiments when the GCTB was allowed to remain over the winter months and removed in the early spring at the start of the ratoon growing season. Of the removal methods evaluated (burning, raking, and shaving), the use of a revolving disk shaver to remove the GCTB had the greatest negative impact on sugar yield. Burning the residue in early March did not adversely impact the crop, but burning in early April did. In three experiments where the GCTB was removed in the fall shortly after harvest, sugar yields were higher than the no removal and spring removal treatments in both first- and second-ratoon crops. Coincidently, the GCTB suppressed the emergence of cool-season weeds by at least 62% and several species of morningglory (warm- season species) by 79%. Results suggest that despite obvious benefits in weed suppression and some freeze protection, growers in Louisiana should remove the GCTB as soon as possible after harvest to limit the potential deleterious effects of the GCTB on the subsequent ratoon crop.