Intensive 3-crop Rotation May Boost Biofuel Economics
by Vicky Boyd (The Grower) Growing a biofuels crop on old citrus ground or rotating it with vegetables just doesn’t pencil out, even with today’s high fuel prices.
But add in a legume cover crop and another short-season oilseed crop, and an intensive rotation may make financial sense, according to trials led by Dan Chellemi, a research plant pathologist with the Agricultural Research Service in Ft. Pierce.
…With tighter soil-fumigation rules looming, Chellemi in 2007 began looking at how crop rotations might help break pest cycles caused by growing the same crop season after season.
“What we’re trying to do is incorporate management of soilborne pests into the overall crop management system,” Chellemi says.
But the question remained, how do you entice growers to take land typically planted to a high-value crop out of production?
“The light bulb went off about five years ago,” Chellemi says. “Maybe if they made money on their rotational crops, they would be more inclined to [rotate].”
… During 2010, he added a legume cover crop, which would supply part of the nitrogen, into the rotation. After 60 days, the legume crop is turned under and may provide up to 200 pounds of nitrogen. But not all of the nitrogen is available at once, since it is slowly released during decomposition.
Next, Chellemi planted sunflowers, but only applied 70 pounds of nitrogen.
Once the sunflowers were harvested, he returned with Camelina sativa, a deeprooted 70-day mustard crop known for producing seeds with high oil and high protein content. Because camelina also is a good nutrient forager, Chellemi applied no nitrogen to the plots.
“Now we can make two oil-seed crops with half the fertilizer,” he says of the oneyear cropping system. READ MORE