|ALLDREDGE, J. - Washington State University|
Submitted to: Crop Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/20/2011
Publication Date: 3/21/2012
Citation: Young, F.L., Long, D.S., Alldredge, J.R. 2012. Effect of planting methods on spring canola (Brassica napus L.) establishment and yield in the low-rainfall region of the Pacific Northwest. Crop Management. doi:10.1094/CM-2012-0321-01-RS.
Interpretive Summary: The winter wheat, highly erosive, weed infested tillage-fallow crop production system has been practiced on 60% of the wheat growing region of the Pacific Northwest (PNW) for over a century. Spring canola has the potential to be an alternative oilseed crop in this region either as an opportunity crop during periods of above-normal precipitation or as a replant crop if fall-planted canola has been winter killed. In 2009 and 2010, a study was conducted in WA and OR to evaluate the effect of no-till planting methods on spring canola plant establishment, yield, and oil quantity. In our study, when crop residue was low (3 of 4 site-years), one of the best no-till planting methods for crop establishment and yield was with a conventional double disk opener, a drill that most growers of the region already own – thus reducing costs by not having to purchase a no-till drill. The use of expensive no-till openers did not improve establishment and yield compared with the double disk openers. Broadcasting spring canola seed, although popular in Canada and Great Britain did not perform well in the PNW in our environmental conditions. This treatment had consistently the lowest crop establishment and yield compared to seeding directly into the soil with all openers. No-till spring canola shows promise as a sustainable crop by reducing weed and disease infestations of wheat, diversifying growers’ production systems and markets, and improving soil and air quality.
Technical Abstract: Growers are becoming interested in producing canola (Brassica napus or rapa) in the dryland, wheat-fallow region of the Pacific Northwest (PNW). Currently, agronomic research for spring canola in this region has not been initiated. This study evaluated the effect of no-till planting methods on stand establishment, crop yield, and seed oil quantity of spring canola in Washington (WA) and Oregon (OR) in 2009 and 2010. The treatments included: double disk opener; broadcast; broadcast plus rolled; Kile opener; cross-slot opener; and hoe opener (at WA only). In this study, canola populations were greatest with the double disk opener and least in the broadcast or broadcast plus rolled treatments at all four site-years. Yield was least in the broadcast treatment and rolling broadcast seed increased yield only 50% of the time. Yields were higher than broadcast and similar for all other openers. The adoption of spring canola in the wheat-fallow region of the PNW would improve pest management strategies, diversify markets, and increase sustainability.