GHGMP News Releases
Forage project demonstrates techniques to benefit the environment
Dawson Creek, B.C., February 17, 2006
A three-year cropping demonstration in B.C.'s Peace River region is designed to show producers across Western Canada improved direct seeding techniques that will not only benefit crop and forage production but also benefit the environment.
The project, supported in part by the Greenhouse Gas Mitigation Program for Canadian Agriculture (GHGMP), is intended to show farmers a process for re-establishing hay and pasture stands without having to till fields, a common practice which not only increases the risk of erosion but also releases stored carbon dioxide back into the atmosphere.
In many situations, hay and pasture fields seeded to domestic forages have a limited life span and need to be reseeded or re-established every few years, explains Julie Robinson of the Peace River Forage Association (PRFA).
A conventional approach in many areas has been to plow and disc these fields through several tillage operations and then re-plant a perennial hay or pasture grass-seed mix.
On annual seeded crop land, dedicated to cereals and oilseeds, for example, an increasingly common farming practice, in recent years, has been to direct seed cereal and oilseeds - such as wheat and canola - directly into last year's stubble without tillage.
"Direct seeding forages, however, presents other challenges," says Robinson, who is also field co-ordinator for the soil and beef sectors of the GHGMP in the northeast B.C. region. The soil sector of the GHGMP program is administered by the Soil Conservation Council of Canada. "The difficulty with direct seeding a perennial back into an unproductive hay or pasture stand is getting good stand establishment and good weed control."
The objective of this demonstration is to develop a system that eliminates the need for breaking the sod and working the field. It appears the best strategy is to spray out the old forage stand with a herbicide, direct seed an annual crop such as oats or barley for preferably two years, and then re-established the new perennial crop into the cereal stubble. This can all be done without tillage.
A decent hay or pasture stand will produce about 2.5 tonnes of forage per acre per year for several years, but as the stand ages and production drops to about one tonne of forage per acre or less, the field is usually tilled and reseeded.
"With tillage there's always the concern about wind or water erosion until the new crop is established," says Robinson. "There's also the cost of the four or five tillage passes needed to break and cultivate a field. At today's fuel prices, that isn't cheap. And from an environmental standpoint, cultivation affects soil structure and also releases carbon dioxide, a harmful greenhouse gas, into the atmosphere."
A healthy, productive forage stand captures carbon dioxide from the atmosphere and stores or sequesters it as carbon in plant leaves and roots and in the soil. Conventional tillage, which breaks the sod and exposes the soil, releases that sequestered carbon.
The GHGMP-funded project, working on two sites, is evaluating different herbicide timings to determine if a fall and spring treatment is needed or just a fall treatment is sufficient to control weeds before the annual crop is directly seeded. Different herbicides and different combinations are being used. A feature report on the project is available on the SCCC website at www.soilcc.ca.
This summer the PRFA will work with Calvin Yoder, an Alberta Agriculture, Food and Rural Development forage specialist from Spirit River, Alberta, to conduct a plant count on the various sites to determine which timing and which combination of herbicide was the most effective.
"Overall, we also need to look at herbicide economics," says Robinson. "There are different products and different combinations of products that may work. For the sake of production economics, we want to see if perhaps a less expensive treatment will do the job."
A report on the results of the various treatments should be ready by the fall of 2006.
For more information, contact:
Greenhouse Gas Mitigation Program for Canadian Agriculture
Dawson Creek, B.C.
Phone: (250) 782-4501
Soil Conservation Council of Canada
Indian Head, Sask.
Phone: (306) 695-4212