What is in this article?:
- Sod-based rotation improves cotton yields
- Recycling nutrients
• Generally, researchers are getting higher lint yields following grazing and yields were numerically higher in the grazed non-irrigated plots than in non-grazed irrigated plots in normal years.
“This is the second year we have looked at the root mass, and down to a meter deep, we have almost twice as many roots from the oat crop following sod as compared to the conventional system. We’re recycling nutrients because the oat roots are able to pick up nutrients from deeper in the soil profile than the conventional rotation, which is the best conservation-tillage we know how to use,” says Wright.
He says yields were measured on cotton, irrigated versus non-irrigated.
“When we first plant, and May is normally dry in the Southeast, the irrigated crop will come up and do well. The non-irrigated looks very poor and stands are slow to establish. But later on, the non-irrigated does catch up. In the smaller plots, for 10 years in a row now, the non-irrigated cotton in the bahiagrass system has out-yielded the irrigated cotton in the standard rotation. A lot of this has to do with the rooting depth and the growth of the roots.”
In the top foot of the soil, he says, there are more nutrients in the grazed versus the ungrazed because cattle are recycling a lot of the nutrients.
“We have about twice the amount of nutrients in the top foot of soil where the cattle are actually recycling the nutrients. Looking at it on a dollar basis, we’re recycling about $120 worth of nutrients over a standard cover crop.”
Looking at yields, in 2007, there was a difference of about 175 pounds of lint where the cover crops were grazed versus not being grazed, says Wright. In the irrigated cotton, there was about 250 pounds more lint than in the non-grazed. In the non-irrigated, the difference was about 450 pounds.
“In 2009, even in the non-irrigated, we made three bales, and conditions were dry.
In general, with small plots and winter grazing, we do have higher yields — two to three to four-bale potential — following bahiagrass with the winter grazing.”
Generally, researchers are getting higher lint yields following grazing and yields were numerically higher in the grazed non-irrigated plots than in non-grazed irrigated plots in normal years, he says. Total nitrogen in the soil and uptake were greater in the grazed plots, grazing winter cover increased cotton yields, and root mass of cotton, peanut and winter grazing were higher following bahiagrass.