Linda F. Benedict, Breitenbeck, Gary A.
Previous research with sugarcane production in Louisiana has shown that semi-banding 10 tons per acre of composted municipal waste under sugarcane rows or placing 40 tons per acre of the compost on top of cane in opened rows at planting can result in increased sugar yields. These studies also showed that adding compost along with the recommended rate of inorganic fertilizer produced larger sugar yields than when only inorganic fertilizer was used.
In 1991, LSU Agricultural Center scientists began a three year study to test the effects on sugar yields of incorporating high rates of compost into sugarcane rows before planting. Bedminster Bioconversion Corporation supplied the composted municipal waste. The study was done on a Baldwin silty clay soil at the Iberia Research Station near Jeanerette.
Compost rates (0, 20, 40, 60, 80 and 100 tons per acre, dry weight) were spread across rows from furrow to furrow and disked into the rows twice. The rows were then opened and planted in mid-October to Kleentek variety CP70-321 at three stalks and a lap of two joints.
The study used a randomized complete block design with three replications. Plots consisted of five 5-foot, 10-inch by 48- foot rows with 8-foot alleys at the ends of the plots, with a border row separating the plots. Fertilizer was applied to the inner off-bar of each row at the recommended rate of 120, 60, 80 and 24 pounds per acre, respectively, of N, P2O5, K2O and S in April of 1992; and at 160, 90, 120 and 24 pounds per acre, respectively, of N, P2O5, K2O and S in April of 1993 and 1994. The rows were “hipped up” to cover the fertilizer.
The three center rows of each plot were harvested each fall and weighed with a weigh rig. A 10-stalk sample was taken at harvest to determine average stalk weight and juice quality for each plot. The effect of composted municipal waste and inorganic fertilizer on sugar yields for three years is shown in Table 1.
Results showed that incorporating large amounts of composted municipal waste into soil before planting can result in large increases in sugarcane yields when inorganic fertilizer is not used. Where the recommended rate of commercial fertilizer was used, however, compost application rates up to 100 tons per acre did not result in increased sugar yields. This indicates that incorporating composted municipal waste into soil may be a satisfactory way to dispose of it, but it would probably not be economical if sugarcane producers had to pay for the compost.
William B. Hallmark, Professor, and Lester Brown, Research Associate, both at the Iberia Research Station, Jeanerette, La.; Allan Wan, Research Associate, Gary A. Breitenbeck, Professor, and Sam Feagley, former Professor, all in the Department of Agronomy, LSU Agricultural Center, Baton Rouge, La.; and Gert Hawkins, Research Associate, Sugar Research Station, St. Gabriel, La.
Research was supported by the Louisiana Educational Quality Support Fund, Bedminster Bioconversion Corp., American Sugar Cane League, Iberia Parish Council, City of New Iberia, Iberia Sugar Cooperative, Cajun Sugar Cooperative, Jeanerette Sugar Co. and M.A. Patout and Sons.
(This article was published in the spring 1999 issue of Louisiana Agriculture.)