Rice planting has mostly wrapped up in Louisiana, and hopefully, most farmers are thinking, “So far, so good.”
It is never too early in the year to start thinking about second, or ratoon, cropping options. The production and harvest of a second crop can increase the productivity per acre. In southern Louisiana, environmental conditions in late summer and fall are often favorable for harvesting a second crop, which develops from the stubble remaining after the first crop has been harvested.
If a farmer plans to second-crop a field, that second crop needs to be considered in every management decision made for the first crop. Planting date, fertilization, and weed, disease, and insect management in the first crop all influence the development and yield of the second crop.
With profit margins as close as they have been in rice production over the last few years, the interest in maximizing second crop production has increased. The current LSU AgCenter recommendation for second crop production (Rice Varieties and Management Tips) is an application of 75 to 90 pounds of nitrogen when the first crop is harvested before Aug. 15 or an application of 30 to 45 pounds of nitrogen when the first crop is harvested after Aug. 15.
Use a nitrogen rate in the upper end of these two rate ranges if there is minimal field rutting, little or no red rice in the first crop, and healthy first crop stubble remaining after harvest.
Apply nitrogen fertilizer immediately following first-crop harvest and establish a shallow flood as quickly as possible. The flood level can be raised to a 4- to 6-inch depth once active vegetative growth begins in the second crop.
Timing is absolutely critical for the second crop because the number of available hours of sunlight for growth and development of the rice plants decreases each day as fall approaches.
Rice farmers in southern Louisiana have also become interested in manipulating first-crop stubble as a means to boost second-crop yields. Some farmers in Texas have realized fairly substantial increases in second-crop yields in fields where the first-crop stubble was clipped to a height of 6 to 8 inches using a flail mower.
Several farmers across southern Louisiana have tried mowing or rolling first-crop stubble in the last couple of years.
At this point, reviews are mixed. Some farmers are really pleased with the results, and others are not. Research results are also inconclusive. One year, mowing first-crop stubble provided a benefit in second-crop yield, and the next year, it reduced yield compared to leaving stubble standing after first-crop harvest.
Any type of rolling or mowing of first-crop stubble delays maturity but promotes uniformity of the second crop. Greater uniformity should lead to even maturity of the second crop, which should, in turn, enhance second-crop grain quality.
In response to questions received concerning second-crop production during the 2004 cropping season, the emphasis on second-crop rice research at the Rice Research Station has increased for 2005. Research will examine the response of second-crop varieties and hybrids to flail mowing and rolling of first crop stubble. Second-crop production will also be compared in water- and drill-seeded production systems.
Other experiments will determine the response of second-crop rice varieties to nitrogen fertilizer applied at different timings, to herbicides applied during the second crop, and to harvest desiccants applied three to seven days prior to first-crop harvest.
The goal of second-crop research in 2005 will be to add to the knowledge base on second crop development and production and to lay groundwork for future research that could lead to more specific recommendations for second-crop production in southern Louisiana.
With good management and the cooperation of Mother Nature, a high-yielding, high-quality second crop can greatly enhance the bottom line. With the current economic situation in rice farming, we should take advantage of every opportunity we have to increase economic productivity.
Jason Bond is a rice agronomist with the LSU AgCenter's Rice Research Station in Crowley, La.