Monday, November 5, 2007 - 10:15 AM
64-4

Sugarcane Post-harvest Residue Management in the Temperate Climate of Louisiana.

Ryan Viator, Richard Johnson, and Edward Richard Jr. USDA-ARS-SRRC Sugarcane Research Laboratory, 5883 USDA Rd., Houma, LA 70360-7189

    Full retention of sugarcane (interspecific hybrids of Saccharum spp.) post-harvest residue often reduces subsequent ratoon crop yields in temparate climates such as Louisiana.  Experiments were conducted to investigate if residue management effects are consistent across ratoon crops of varying age, to determine if residue management by soil type interactions exists, and to determine the effects of removal method and removal timing on sugarcane growth and yield.  First, second and third ratoons on both a heavy and light soil were utilized. Removal methods consisted of partial mechanical removal, complete removal by burning, and full residue retention (control).  Removal timings consisted of the following physiological stages: pre-dormancy, complete dormancy, intermediate dormancy, and post-dormancy.  Ratoons did not respond similarly to residue management, and soil type can influenced residue management.  Early removal during pre-dormancy and complete dormancy appear to be the best time to remove the residue.  Removal during these two stages via mechanically or burning resulted in yield increases of 5% compared to full retention.  Mechanical removal produced similar yields as burning except in first-ratoons where burning during pre-dormancy produced 510 kg ha-1 more sugar.