GHGMP Project Reports by Region
N.B. producers are finding the reduced tillage zone
There's the will and now a way to make zero-till crops work
New Brunswick farmers aren't giving up on zero-till. While not all 2003 reduced tillage demonstrations projects showed the full benefits of conservation farming, more demonstration test plots and more independent producers are looking to make zero-tillage and conservation farming practices work this year.
Farmer interest in using two zero-till corn planters has increased for the 2004 planting season, say specialists. Bookings for two planters bought last year by the New Brunswick Soil and Crop Improvement Association have increased from a few dozen acres last year to nearly 750 acres on a number of farms this spring. The planters, leased in part by funds from the federal Greenhouse Gas Mitigation Program (GHGMP) are rented to producers. The GHGMP funds demonstration projects promoting the awareness of soil conservation and the reduction of greenhouse gas emissions.
"More farmers are interested in making zero-till work," says Pat Toner, a soil management specialist with New Brunswick Agriculture, Fisheries and Aquaculture in Fredericton. "Producers should be able to grow high yielding, economic crops under zero-till. It's a matter of figuring out the right conditions.
"Last year was a tough year no matter what system people used. It was a very cold, wet spring and it was only the first year of the project. We'll be able to make a better assessment of zero-till after a couple more years."
Several demo sites
Zero-till and conservation tillage systems were demonstrated last year at seven sites across New Brunswick. Field scale plots included wheat, silage corn and silage barley. Similar demonstrations will continue in 2004 with at least two added sites evaluating conservation tillage on potatoes.
Zero and minimum tillage practices have the potential to produce several benefits. The technique reduces farm input costs while hopefully maintaining or improving yields. On the environmental side, there's reduced risk of soil erosion, improved soil quality and reduced greenhouse gas emissions. As organic matter decomposes, carbon in the soil is released to the atmosphere as carbon dioxide. The most effective way to reduce decomposition is to reduce or eliminate tillage.
The New Brunswick projects compared three different systems. Conventional tillage involves plowing fields in the fall and then making a combination of passes with a disc and harrows to prepare a seedbed. Conservation tillage treatments used a lower-disturbance chisel plow for the primary tillage pass, followed by secondary tillage. The zero-tillage system meant planting crops directly into crop residue with either the zero-till corn planter or a stubble grain drill.
Of the three crops, corn showed the weakest results, says Toner. At most sites, input costs were down using zero and conservation tillage, but silage corn yields were also down. Cold soil was largely to blame, he says. "The crop residue just didn't allow heavier soils to warm up and with the cold, wet conditions, crop growth was slow."
Silage barley performed well under zero till. One site in particular, with a 10-year history of zero tillage, clearly showed the benefits of the system. Silage barley yields under zero till were as good as the long-term average of conventionally-grown barley. However, fuel consumption under reduced tillage was dramatically reduced. Fuel requirements were cut by about 40 percent under conservation tillage, and by about 70 per cent under zero-till.
"The fuel and time savings stem from a combination of reduced field operations and the fact that it takes less horsepower for equipment to work through soil that is more mellow and has more tilth," says Toner. Using less fuel also benefits the environment through reduction of greenhouse gas emissions.
The zero-till projects also showed a difference in crop performance over different soil types and field exposure. Silage corn yields were lower on the heavier textured silt loam, however, on the more rolling, gravely and medium-texture loam and sandy soils, yields were respectable. "I suspect the rocks or the texture of the soil may hold the heat better than the heavy clay soils," says Toner.
Zone tillage option
Projects for 2004 include demonstrations of zone or strip tillage, particularly on heavier clay sites, to help warm the soil. Fields aren't plowed, the zone tillage tool clears a strip of residue in corn-row widths, allowing the exposed soil to warm before planting using either a conventional or no-till planter.
Another project demonstrates direct seeding corn into alfalfa field stubble, after the alfalfa has been killed with a herbicide.
The benefits of switching from conventional to a reduced or no till system can't be realized in just one year, Toner says. It takes perhaps two to four years for soil microbes to adjust and reach a new equilibrium. As soil organic matter increases, the benefits of improved tilth and water infiltration can be seen.
Zero tillage is new territory for the majority of producers, he says. "Farmers are interested in conservation farming practices, but they need to see the systems work and see what tools are available," he says. "The goal is to, hopefully, reduce input costs, while at least maintaining yields. Improving soil quality through conservation farming is an added benefit in developing a sustainable farming system."
Regional reports will be posted as information becomes available. Please check back regularly for updates.