Conservation tillage, like happiness, is different things to different people, but missionaries for the cause continue to carry the word of anecdotes and research to prospective converts.
One definition of conservation tillage is it leaves a third or more of the previous crop residue in the field as the new crop is planted on beds from the season before.
Usually it significantly reduces the number of trips across fields in preparation for the new crop, but in many cases, there is no tillage before seeding.
Compaction, moisture, erosion, and carbon content of the soil and quality of the atmosphere are among key issues, but costs of fuel, equipment, and labor also are prominent.
Old hands at conservation, or reduced, tillage aren’t so hard to find elsewhere in the country, and non-tillage acreage in the U.S., largely to curb soil erosion, is said to have expanded from 3 million acres in 1972 to nearly 51 million by 2000.
Despite ambitious research, on and off the farm, the conservation-tillage gospel spreads at a glacial rate in California’s Central Valley as most growers wait to see how things turn out.
It is unlikely it will be broadly adopted by all the state’s many specialty crops, although many growers may find some parts of it work for them.
Plenty for practice
For the time being, there’s plenty of field crops for practice. Stung by high production costs and low commodity prices, curious but wary growers keep one eye on their ledgers and the other on an aggressive neighbor trying conservation tillage down the road or across the county.
Near Five Points recently, the cautious mingled with the aggressive to learn more. The University of California staged a Conservation Tillage Conference at the West Side Research and Extension Station, complete with examples of the necessary hardware, for nearly 200 persons.
A dozen or so pieces of equipment demonstrated at the event were designed either for planting a new crop immediately after the preceding crop is harvested, for working-in heavy residue before planting, or for guidance by global positioning systems.
Jeff Mitchell, UC vegetable crops specialist and organizer of the event, said conservation tillage is apt to be redefined for California conditions as more is learned.
Conceding the concept has far to go, Mitchell said feedback from conferences in recent years "indicates that conservation tillage will become more widely adopted throughout the state once successful examples are demonstrated."
To share accumulated knowledge, he assembled a panel of growers to relate their experience with on-farm test plots.
One, John Diener of Five Points, a veteran of several years’ work with reduced tillage practices, said his objective with conservation tillage is to convert to a five-row, 60-inch culture for tomatoes, cotton, and wheat.
"With guidance systems we will get the uniformity and precision we need to maintain the beds over a period of time and reduce the number of passes," he said.
Diener showed his 10-acre trial of emerged DP-458 Roundup Ready Pima cotton. It was planted five days before the conference through wheat residue, the same day the wheat was harvested. Depending on how the stand progresses, Diener said he may stripper-harvest the field.
Rick Neuenschwander of Woolf Enterprises at Huron said he reduced tillage for tomatoes behind onions or wheat to two to five passes, vs. five to nine trips across the field under conventional practices. His primary tillage cost $5 per acre, in contrast to conventional practices at $13-$15 per acre, while other steps also were done at substantial savings.
"The bottom line," he said, "is we are saving about $70 an acre, and we’ve been able to avoid compaction by never running equipment tires over the plant line."
Bob Prys of Borba Farms at Riverdale also cut the number of passes across the field by planting Roundup Ready cotton into wheat stubble. He used both Buffalo and John Deere planters and saw good results from both.
"It’s a work in progress, and I heard from a lot of skeptics to begin with. The cotton is the same height, set and maturity as our conventional fields. So far it looks beautiful."
Dick Newton of Jones Farms at Stratford has grown tomatoes, cotton, and garbanzo beans on drip irrigation and is now moving into conservation tillage to increase soil organic matter.
For his 2002 season cotton he plans to limit the work to three operations: shred the stalks, pull the roots, and run a Northwest tiller. The conventional routine is 10 passes. He added that with a global positioning system, he believes he can operate the tiller without an additional pass to pull roots.
Tulare dairyman Vernal Gomes, who said conservation tillage "has unlimited possibilities," irrigates with dairy lagoon water and faces the typical struggle with massive amounts of weed seeds in the water.
With Roundup Ready silage corn planted dry in winter wheat stubble, he saved $70-$75 per acre in a program limited to two applications of Roundup.
Without pre-irrigation, drying-out time, and working of beds, he also saved three to four weeks in getting the crop on its way.
Taking the idea a step farther, he harvested the corn silage after 90 days and then planted sorghum-sudangrass, for a triple crop program. He said the double- and triple-crop capabilities are important to intercept nitrates that would otherwise leach into the soil.
No-till disciple Max Carter of Douglas, Ga., who said he started converting his 400 acres to no-till in 1974 to control erosion, offered an out-of-state perspective. He grows cotton, corn, peanuts, soybeans and makes liberal use of cover crops
After a quarter-century of no-till, the ground’s organic matter has increased, despite its sandy texture. Other benefits are virtually eliminated runoff, increased beneficial insects, and more plentiful wildlife.
He claimed he has plenty of time for fishing and golf while the neighbors are busy plowing in winter and early spring.
"The key to no-till on my farm is crop residue management," he said. "You must start preparing for the next crop during the harvest of the current crop. If the crop residue is spread properly, the following crop can be planted without difficulty with a no-till planter or a no-till drill."