• By Dennis Pollack •
California cotton growers have often dreamed of finding themselves in tall cotton. These days, they might just find themselves in a tall cotton cover crop—as high as 5 or 6 feet, according to one expert on the value of cover cropping to improve soil health.
That expert was among speakers at a University of California workshop organized by UC cropping systems specialist Jeff Mitchell. During the event, he posed a rhetorical question: “How do we get to $2.50 a pound cotton in the San Joaquin Valley?”
He conceded that’s an optimistic figure—”perhaps overly optimistic”—but his aim was to trigger a discussion on how to see higher returns.
Cotton has been pegged at around 62 cents per pound, he said, a price that makes turning a profit challenging.
Farmers who spoke during the virtual meeting included Gary Martin with Pikalok Farms in Mendota, John Teixeira with Lonewillow Ranch in Firebaugh, Derek Azevedo with Bowles Farming in Los Banos and Nathaniel Siemens of the Rodale Institute in Ventura.
Walkin’ in tall cover
It was David Lamm of Greensboro, North Carolina, project manager with the Soil Health Institute, who talked of crop covers as high as 5 or 6 feet. He advocated minimizing disturbance of the soil, maximizing diversity of plants in rotation cover crops, keeping living roots in the soil as much as possible and keeping the soil covered at all times with plants and plant residues.
Rebecca Burgess, executive director of Marin County-based Fibershed, said she favors many of the same approaches, as well as application of compost.
She described a C4 Brand Collaboration, the California Cotton and Climate Coalition, which seeks to move away from synthetic nitrogen and deeper into natural integrated pest management, untreated seeds, reduced soil disturbance and keeping living roots in the soil.
Cala Rose Ostrander of the People, Land and Life Foundation in Colorado discussed the importance of rebuilding carbon stocks in cotton-producing landscapes, taking carbon from the atmosphere and supporting farmers seeking alternatives to synthetic inputs.
One of the farmers, Martin, pointed to cover cropping benefits that include improved infiltration while the cover crop is growing, improved soil structure, increased organic matter and enhanced water retention—but he also pointed to challenges that include the expense of planting the cover crop and keeping it alive with irrigation.
“Planting and tillage practices need to be aligned with cotton management,” Martin said.
Among factors he raised were the cost of applying and irrigating a cover crop, the cost of applying gypsum and of applying compost.
In his discussion of soil health, Teixeira said, “Microbes are the future; keep them alive, they work 24/7.”
He referred to peas as a cover crop with a nodule that’s “like a nugget, capturing atmospheric nitrogen; it’s like money, eliminating synthetic nitrogen.”
Teixeira described the importance of having supply sources close. He accesses dried dairy manure for compost and seeks to have it no more than 25 miles from his operation, to keep trucking costs down.
Azevedo explained that Bowles Farming uses 70 species of California native plants and has its own nursery.
“Yield,” he said, “is the ultimate finish line,” adding that healthy soil practices maintain or even improve yields.
Siemens referred to grazing sheep, used to help remove the cover crop when the time comes to do so, as “unpaid interns.”
After the sheep do their thing, the next steps are to mow and mulch. He said his organic Rodale operation is also looking into other means of removal through defoliation, including heat and steam.
Another speaker, Gary Crum, a crop consultant and regenerative-agriculture specialist with California Ag Solutions Inc. in Madera, said, “Ultimately, farm sustainability is determined by profits,” and “soil health equals profitability.”
He reiterated the importance of keeping soil covered with residue, minimizing soil disturbance, adding plant species, cover cropping between cash crops and integrating livestock.
Covers help suppress weeds
A cover crop also helps cut down on weeds, he said.
“If you don’t put a cover crop on the ground,” Crum said, “God will send you a cover crop of weeds.”
Crum said he works with farmers to achieve both short- and long-term goals and to “see their production system differently.”
He said cover cropping increases water holding capacity, nutrient cycling and microbial activity; changes pest, pathogen and disease cycles; and eventually allows reduced inputs of nutrients, pesticides, herbicides and fungicides.
In addition, speakers said, reduced tillage passes mean less wear and tear on equipment and less use of fuel and labor.
Mitchell closed the meeting with a talk about 20 years of soil management research conducted at the UC West Side Research and Extension Center in Five Polnts.
Annual cover copping has added 37 tons of organic matter and captured 15 tons of carbon per acre with use of about 12 inches of water, he said.
“Reduced-tillage plots with cover crops show higher water storage,” he added.
(Dennis Pollock is a reporter in Fresno. He may be contacted at email@example.com.)
The article originally appeared in Ag Alert, the California Farm Bureau Federation’s weekly newspaper.