For Dennis Burns, the coordinator of the LSU AgCenter Northeast Research Station, a single photo sums up something he and several colleagues have been studying extensively: the benefits of conservation methods such as planting a cover crop in the offseason.
“I took a picture last year,” Burns recalled at a field day at the station. “We had ground that was prepared for the winter and sprayed with a herbicide. The water coming out of the field, out of the culvert was brown. There was a cover crop field right down the road, and the water coming out of there was clear.”
Cover crops help stop erosion, and many farmers have already implemented them to protect their soil, add nutrients to it, break up compacted areas and ultimately grow a better cash crop.
Biomass, Nutrient Content
The biomass created by cover crops provides organic matter and nutrient content to the soil. AgCenter soil scientist Lisa Fultz is determining whether farmers can scale back current recommended seeding rates and still achieve the same amount of biomass, which would represent a significant cost savings. It seems to be a viable move with some cover crops, but not all, she said.
Graduate student Andres Carrillo is using digital technologies from satellite imagery, drones and handheld sensors to estimate the amount of biomass produced by cover crops. The goal is to couple biomass data with nutrient content to estimate nutrient release and availability to later cash crops.
AgCenter soil scientist Brenda Tubaña is quantifying specific amounts of nitrogen, phosphorous, potassium and sulfur that various cover crops provide.
“This is very useful for cutting down on unnecessary fertilizer applications while maintaining yield,” she said.
Tubaña also is evaluating strategies to scale back fertilizer applications while preserving yields, which benefits both the environment and farmers’ income.
“We are taking care of the soil, and we are taking care of the productivity of the field,” she said.
Inhibits Weed Growth
Cover crops also can help reduce herbicide use. Burns has been studying rolling and crimping covers when it’s time to plant a cash crop. Roller-crimper machines flatten the cover crop, creating a mat that naturally suppresses weed growth.
“It’s just like you are using a mulch material,” said postdoctoral researcher Peters Egbedi, who also is examining the practice.
Many others from the AgCenter spoke at the field day, including economist Naveen Adusumilli, agent James Hendrix, weed scientist Donnie Miller, corn and cotton specialist Matt Foster and Louisiana Master Farmer Program coordinator Donna Gentry.