Story Posted: January 19, 2011

Canola Watch: Management tips for unseeded acres

In This Issue: Management tips for unseeded acres, Share your experiences with us, For more discussion on unseeded acres topics..., Questions and contacts.

Management tips for unseeded acres
Canola growers with excessive moisture in 2010 face many unknowns and issues for 2011. The following tips will help growers prepare these fields for 2011:

Get a soil analysis. Nutrient reserves will be difficult to predict, especially in low areas flooded for long periods. Lack of oxygen limits microbial breakdown of organic matter. Therefore nutrients made available through mineralization will be lower than expected in these low-lying areas. Leaching of nitrogen and sulphur and denitrification of nitrogen will be higher in those areas as well. Test saturated areas separately. If results are different from the rest of the field, adjust fertilizer rates for these areas to improve your dollar return and fertilizer efficiency.

Tillage can have unwanted side effects:

• Tilling to dry out wet soil can increase compaction of the topsoil and subsoil layers. Compaction reduces root growth, uptake of nutrients, and future tolerance of both flooded and dry conditions. Tillage in the spring can also create a rough seedbed, making consistent seed depth and good seed-to-soil contact hard to achieve.
• Tillage can bring long-buried weed seeds to the surface. These seeds may germinate in large numbers when conditions are favourable. In addition, tillage will have redistributed seeds that were on the surface throughout the tillage layer. This could extend the emergence window, making herbicide staging more difficult. Finally, tillage may stimulate the emergence of weeds that had declined in number under direct seeding management systems.

Unseeded fields can be considered a "break" from canola - as long as canola volunteers were controlled. Volunteer canola contributes to disease inoculum build up in the soil.

Residual herbicides may still be active. Oxygen is required for microbial breakdown. Saturated soil lacks oxygen. So, ironically, residual herbicide breakdown in wet soils can be as slow as breakdown in a drought year. Check herbicide records before seeding canola.

Weed pressure will depend on 2011 conditions, not 2010 conditions. Wet conditions in 2010 will not result in a significant shift in weed populations toward water loving species. Unless there has been a recent introduction of a new weed from outside the field, historical populations should be a good guide to what species of weeds will emerge in 2011. As for the weed seedbank, wet conditions may have caused many dormant seeds to germinate and may have resulted in heavier seed mortality from decay organisms. If weeds that emerged were effectively controlled, weed densities in 2011 may decline. But if weeds that emerged were not controlled and produced seed, the soil seed bank could have been replenished or even increased slightly for 2011. Higher weed densities will require better herbicide spray coverage to maintain effective weed control, especially those with contact activity. Keep water carrier volume at the high end of the recommended range to ensure that all weeds receive an adequate dose of herbicide.

Share your experiences with us
When unusual events happen - such as way too much moisture for normal operations - growers often have experiences that may provide useful tips in case a similar event happens again. Did you try anything new or unusual for seeding, fertility, weed control, harvest or other management situations that you'd like to share? We want to hear about things that worked and didn't work. We'd also like to hear comments that may add to the points made above. Please email Jay Whetter with a description of what you did and how it worked for you.

For more discussion on unseeded acres topics...
SaskCanola is sponsoring several events that will address concerns about unseeded acres and other canola-related information.

2011 SaskCanola Producer Webinars:

• March 1, 10:00 a.m. Fertility Issues with Unseeded and Flooded Acres. Host Dr. Jeff Schoenau, soil fertility scientist, University of Saskatchewan.
• March 3, 10:00 a.m. Unseeded Acres and Field Management. Host Lyle Cowell, manager agronomic services, Viterra, Tisdale, Saskatchewan.
• March 8, 10:00 a.m. Unseeded Acres and Disease Management. Host Faye Dokken-Bouchard, provincial plant disease specialist, Saskatchewan Ministry of Agriculture.
• March 10, 10:00 a.m. Unseeded Acres and Weed Management. Host Clark Brenzil, provincial weed control specialist, Saskatchewan Ministry of Agriculture.
• Click here for more details and registration information.

2011 Regional Producer Meetings:

• February 9, Melfort
• February 10, Rosetown
• February 15, Battlefords
• February 16, Humboldt
• February 17, Estevan
• Click here for more details and registration information.

Radio programs with canola information:

• CJWW Saskatoon: Canola Connection every Wednesday noon
• CJVR FM and CK750 AM Melfort: First Friday of the month at 12:30 p.m.
• Golden West Radio 1330 Rosetown, 1210 Kindersley, CHAB Moose Jaw, CKSW Swift Current: Second Friday of the month at 1:00 p.m.
• Rawlco Radio CNJB 1050 North Battleford/Meadow Lake: Second Sunday of the month at 11 a.m.

Questions and contacts
If you have general questions about Canola Watch, direct them to Jay Whetter, whetterj@canolacouncil.org or 807-468-4006.

If you have questions on regional issues, contact one of the following Canola Council of Canada regional agronomists or provincial oilseed specialists:

• Derwyn Hammond, resource manager, crop production, hammondd@canolacouncil.org, 204-729-9011
• Jim Bessel, senior agronomy specialist, Central Saskatchewan, besselj@canolacouncil.org, 306-373-6771
• Tiffany Martinka, agronomy specialist, Eastern Saskatchewan, martinkat@canolacouncil.org, 306-231-3663
• Clint Jurke, agronomy specialist, Western Saskatchewan, jurkec@canolacouncil.org, 306-821-2935
• Troy Prosofsky, agronomy specialist, Southern Alberta, prosofskyt@canolacouncil.org, 403-332-1412
• Doug Moisey, senior agronomy specialist, North East and East Central Alberta, moiseyd@canolacouncil.org, 780-645-9205
• Erin Brock, agronomy specialist, Peace Region, brocke@canolacouncil.org,
  780-568-3326
• Murray Hartman, Alberta Agriculture and Rural Development, murray.hartman@gov.ab.ca, 403-782-8024
• Kerry Clark, B.C. Ministry of Agriculture and Lands, Kerry.Clark@gov.bc.ca, 250-784-2559
• Venkata Vakulabharanam, Saskatchewan Ministry of Agriculture, Venkata.Vakulabharanam@gov.sk.ca, (306)787-4668
• Anastasia Kubinec, Manitoba Agriculture, Food and Rural Initiatives, anastasia.kubinec@gov.mb.ca, 204-750-2717

This report is supported by each of the provincial canola grower associations. For more information on some of their activities, check out the following links:

• The Alberta Canola Producers Commission (ACPC) has a free e-newsletter called Alberta Canola Connections. Visit canola.ab.ca and click the sign-up icon on the right site of the homepage.
• In Manitoba, sign up for the Manitoba Canola Growers Association newsletter at Canola Growers E-update by visiting www.mcgacanola.org.

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