Canola Watch

2006 Canola Watch Reports

Canola Watch Report No. 6
Western Canada – May 31, 2006

In this issue:
(click the bookmarked links below to move to specific sections of this report)

The Alberta Canola Producers Commission (ACPC) has developed an Alberta focused version of this report. Visit the ACPC website at: http://www.canola.ab.ca

Canola seeding was limited this past week across much of western Canada due to continued cool and showery weather.  Continued seeding delays are being experienced in parts of northwestern Manitoba, northern and east-central Saskatchewan and the eastern part of north-central Alberta with about 25-75% completed. Wet conditions and regular precipitation continue to limit rapid seeding progress in these areas.

Soil moisture conditions range from fair to excessive across western Canada. Precipitation this past week ranged from a trace up to over 125 mm from localized thundershowers. Areas of east-central and northern Saskatchewan and northwestern and southeastern Manitoba remain wet. The small pockets of dryness in parts of southwestern Saskatchewan and parts of central Alberta near Red Deer were relieved somewhat by recent precipitation which will assist in germination and early crop development, but continued rains will be needed in these areas to charge subsoil moisture levels.

For current maps of moisture conditions from PFRA for western Canada, check the following links for precipitation from September 1 to May 29 and April 1 to May 29 respectively:
http://www.agr.gc.ca/pfra/drought/prpay06_e.htm
http://www.agr.gc.ca/pfra/drought/prpgs06_e.htm
http://www.agr.gc.ca/pfra/drought/index_e.htm

The latest crop report from Manitoba Agriculture, Food and Rural Initiatives is available at:
http://web2.gov.mb.ca/agriculture/mwcr/

The latest crop report from Saskatchewan Agriculture, Food & Rural Revitalization is available at:
http://www.agr.gov.sk.ca/docs/reports/crop_report/crprpt060528.pdf

The latest crop report from Alberta Agriculture, Food & Rural Development is available at:
http://www.gov.ab.ca/acn/200605/1999087254833-D9FE-445C-03EA0BFCB85FD1F5.html

Additional moisture information for Alberta is available from Alberta Environment at:
http://www3.gov.ab.ca/env/water/WS/data/precipmaps/weekly.pdf

Weed growth continues in most areas, and is becoming heavy due to warmer temperatures and good moisture, especially in fields that did not receive pre-emergent burn-off applications. Spraying delays due to rains and wet fields are compounding the problem in many areas. Frequent scouting remains important to assess the number and types of weeds present as well as their growth stage. Ensure the proper rate and product(s) are used to control the weed stages and spectrum present. Also, in areas affected by extreme weather (either very wet or dry conditions) ensure that the herbicide rate chosen is appropriate to allow good crop tolerance and adequate control of target weeds.

For more information on current product recommendations, check the following links from the provincial governments for their respective Crop Protection Guides:
http://www.gov.mb.ca/agriculture/crops/cropproduction/gaa01d01.html
http://www.agr.gov.sk.ca/DOCS/crops/cropguide00.asp
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex32?opendocument

Growers who still have canola left to seed should be reassessing the maturity suitability of their chosen varieties. The accumulation of temperature or Growing Degree Days (GDDs) has a major influence on days to maturity for canola. In the short and mid season zones of western Canada, maturity for B. napus varieties will range from 95 to 125 days, depending on the growing season heat accumulation. B. rapa varieties usually range from 80 to 115 days to maturity.

First, find out how many days to maturity are required for the variety that is to be seeded. Usually the variety will be rated as; number of days earlier (minus) or later (plus) or equal to the check. Using a typical first fall frost date, count back the days to maturity to get to the safe seeding date. For example, if the average first frost is August 25 and maturity of the check in the area is 103 days, counting back gives a safe seeding date of May 17. If the variety to be seeded is five days earlier maturing than the check, this means that in a typical year, seeding up to May 22 should be acceptable for that variety. If the variety does not meet the requirements, ask your local retailer to suggest other suitable varieties.

Manitoba growers can check the following link to determine their frost-free days:
http://www.gov.mb.ca/agriculture/climate/waa50s00.html

Saskatchewan growers can check the following link from Saskatchewan Crop Insurance to check the mean date of the first fall frost in their area:
http://www.saskcropinsurance.com/maps/other/fallfrost.shtml

Alberta growers can check the following link to determine their frost-free days:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex10304

As the seeding window for canola closes, producers looking at reducing the days to maturity by switching to a B. rapa (Polish) variety should keep in mind the pros and cons when switching from a B.napus variety.

The largest disadvantage in switching to a B. rapa variety is a potential yield reduction of 30% or more when compared to a mid to high yielding B. napus variety.  As well, the switch will mean relying on conventional herbicides to control weeds.  One recommendation is to apply a higher rate of glyphosate in a pre-seed burn-off to control large and rapidly advancing weeds. This should take care of most weeds that may have germinated allowing the B. rapa variety to germinate and grow in a relatively weed free environment.  Any subsequent flushes of weeds will require the use of conventional herbicides.  Another disadvantage is the increased potential for alternaria blackspot which can result in the requirement to swath to protect the yield potential of the crop.

The largest advantage to switching to a  B. rapa variety is the reduction in days to maturity which will give a greater potential to harvest the crop as a #1 canola versus the potential risk of a late seeded B. napus variety grading#3 or Sample.  The potential economic penalties from a reduction in yield could easily be offset by better grades.  Another advantage to switching to a B. rapa variety is the potential to straight cut.  This advantage is twofold.  First, the ability to straight cut eliminates the costs of swathing and minimizes the potential yield and grade losses sometimes associated with swathing too early, provided this can be done prior to fall frost.  The second advantage to straight cutting, associated with better shatter resistance of B. rapa varieties, is that the crop can remain standing while other crops are being harvested/swathed thus allowing for better time management for producers.

The delay in seeding progress due to wet weather has led to many questions regarding the feasibility of broadcast seeding. In general, broadcast seeding is not recommended. Usually, broadcast seeding results in lower yields compared to drill seeding. However, producers faced with wet conditions that limit equipment flotation plus the risk of fall frost may wish to consider broadcast seeding. Here are some tips for enhancing the success of broadcast seeding.

  • Increase seeding rates slightly to compensate for non-uniform seed depth.
  • Consider lightly cultivating (2-4 cm) or harrowing to incorporate the seed into the soil if soil conditions allow.
  • Avoid creating lumps or clods during cultivation or straw piles with harrows or cultivators.
  • If broadcasting fertilizer as well as seed, be aware that broadcast phosphorus is only about half as efficient as banded phosphorous. There can also be greater risk of denitrification on saturated soils, reducing N fertilizer efficiency. Adjust fertilizer rates accordingly, keeping in mind a realistic target yield based on the time of year and field conditions.

Although seeding dates are getting late in many areas, it is very important that growers follow proper seeding practices. Seed shallow to facilitate rapid emergence, ideally at a depth of 1/2 to 3/4 of an inch. Seed slow for proper seed-soil contact and to ensure that most of the seed is placed in the required zone. Apply recommended rates of phosphorus fertilizer for the faster pop-up effect and to assist in hastening crop maturity, especially if conditions remain cool and wet.

Keep any pre-seeding tillage shallow to help maintain the seedbed firmness and moisture. Make sure that seeding rates are high enough to establish the target of 7-14 plants/ft2.

Refer to the following weblink for further information on establishing proper plant populations:
http://www.canola-council.org/PDF/plant_pop_profit.pdf

Remember to begin scouting fields by 7 to 10 days after seeding to detect germination problems early. With ample moisture and warm soils emergence can begin to take place within a week. Refer to the following Canol@Fact for more information:
http://www.canola-council.org/PDF/seed_to_21days.pdf#zoom=100

For anyone encountering stand establishment problems, we encourage you to refer to the following template form from our website:
http://www.canola-council.org/growing_poor_stand.html

Please fill out this form and return via email according to the instructions outlined on the webpage.

Flea beetles continue to be reported in many parts of Saskatchewan, and in central Alberta near Wetaskiwin, Wainwright and St Albert. Many of the reports continue to be noted on volunteer canola and wild mustard, or on fields with tight canola rotations or where no insecticide seed treatment was used. Refer to last week’s Canola Watch report for further information on assessing flea beetle damage:
http://www.canola-council.org/seed/canola-watch/watch06-may25.html

Cutworms have been noticed near Cabri and Swift Current SK. Be especially vigilant in areas that had cutworm damage last year.  Refer to 2006 Canola Watch No. 5 for further information on identification and control.

Direct questions regarding this report to John Mayko, Agronomic Research & Extension Manager with the Canola Council of Canada at maykoj@canola-council.org  ph/fax: 780-764-2593.

Direct specific questions regarding regional issues to one of the following Canola Council of Canada agronomists or provincial oilseed specialists:

Derwyn Hammond, Agronomist, Manitoba,
hammondd@canola-council.org, 204-729-9011

Rob Park, Manitoba Agriculture, Food & Rural Initiatives,
rpark@gov.mb.ca, 204-745-5665

David Vanthuyne, Agronomist, Eastern Saskatchewan,
vanthuyd@canola-council.org, 306-782-7799

David Blais, Agronomist, Western Saskatchewan,
blaisd@canola-council.org, 306-895-2122

Jim Bessel, Senior Agronomist, Northeastern Saskatchewan,
besselj@canola-council.org, 306-373-6771

Penny Pearse/Scott Hartley, Saskatchewan Agriculture, Food & Rural Revitalization,
ppearse@agr.gov.sk.ca / shartley@agr.gov.sk.ca , 306-787-4671 / 306-787-4669

Doug Moisey, Agronomist, Central Alberta,
moiseyd@canola-council.org, 780-645-3624

Jackie Heck, Agronomist, Peace River Region,
heckj@canola-council.org, 780-853-5261

Matthew Stanford, Agronomist, Southern Alberta,
stanfordm@canola-council.org, 403-758-6660

Murray Hartman, Alberta Agriculture, Food & Rural Development, murray.hartman@gov.ab.ca, 403-782-8024

Kerry Clark, BC Ministry of Agriculture, Food & Fisheries,
Kerry.Clark@gov.bc.ca,  250-787-3213

The Canola Watch Report provides just-in-time information on canola production to growers and industry. Contributors to the Canola Agronomy Network are:

Manitoba Agriculture & Food; Manitoba Canola Growers Association; Agricore United; Saskatchewan Wheat Pool; United Farmers of Alberta; Saskatchewan Agriculture, Food & Rural Revitalization; Saskatchewan Canola Growers Association; Saskatchewan Canola Development Commission; Alberta Agriculture, Food & Rural Development; Alberta Canola Producers Commission; BC Ministry of Agriculture; Food & Fisheries; and the Canola Council of Canada.

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