#19 Western Canada – September 6, 2007
Final Report for 2007 Season
In this issue:
(click the bookmark links below to move to specific sections of this report)
Harvest progress most variable in years
Frost may have damaged some canola crops
Late season diseases showing up
Growers asked to report new blackleg strains
Assess seed colour change before swathing
Avoid swathing when seeds are translucent and watery
Let canola cure in the swath longer
Watch for stubble greening after swathing
Reduce risk of wind blown swaths
Keep malathion far away from canola bins
Use diatomaceous earth products correctly
Keep stored canola cool and dry
Post harvest weed control may be an option this year
Fall soil testing is useful management tool
Final Canola Watch report for the 2007 season
Watch for CCA Exam
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
Harvest progress differs greatly among regions with the widest variation in recent years. Many areas of central and eastern Manitoba are finishing combining while areas of west-central Alberta and the Peace region are only about 20% swathed. Showers and cooler weather have tended to delay maturity and subsequent harvest. Reports of smaller than normal seed size have been widespread across all areas where significant combining has occurred.
An overview of prairie vegetation conditions is available at (use the “start the prairies application” button on the left hand side): http://www26.statcan.ca/ccap/ccaphome_en.jsp
The latest crop report from Manitoba Agriculture, Food & Rural Initiatives is available at: http://web2.gov.mb.ca/agriculture/mwcr/index.php
The latest crop report from Saskatchewan Agriculture, Food & Rural Revitalization is available at:
http://www.agr.gov.sk.ca/docs/reports/crop_report/crprpt070903.asp
For current maps of moisture conditions from PFRA, check the following links for precipitation since September 1, 2006 and April 1, 2007 respectively:
http://www.agr.gc.ca/pfra/drought/prpay07_e.htm
http://www.agr.gc.ca/pfra/drought/prpgs07_e.htm
Additional moisture information for Alberta is available from Alberta Environment at: http://www3.gov.ab.ca/env/water/WS/data/precipmaps/weekly.pdf
Frost was reported this past week in parts of northwestern Saskatchewan including Spiritwood, Medstead, Rapid View, Pierceland and Unity. Although the frost damage was light in many areas, some low lying areas likely experienced more damage.
Wait a few days to accurately determine frost damage and decide on an appropriate course of action. For more information on assessing frost damaged canola refer to the following links: http://www.canola-council.org/PDF/sept20_canola_fact_sheet_r3.pdf
http://www.agr.gov.sk.ca/docs/production/frost_greenseed.asp
Reports of late season diseases continue, including: high levels of sclerotinia in untreated fields in parts of Manitoba, northern Saskatchewan, central Alberta and the B.C. Peace; aster yellows across all areas; clubroot around Edmonton, Leduc, St. Albert and Westlock, AB; alternaria in northwestern SK and north central AB; and fusarium wilt and blackleg in south central MB. Fields that received hail damage appear to be more prone to secondary disease development. Although there is nothing that can be done at this point in the season, records of disease incidence can assist in rotation and other management decisions for next year.
To keep track of new strains of blackleg, growers who notice elevated blackleg levels in MR and R rated varieties are encouraged to collect samples and have them tested to determine what strain is present. Interested growers should e-mail Dr. Dilantha Fernando at fernando@cc.umanitoba.ca for sampling and shipping instructions.
During fall scouting for proper swath timing, watch for abnormal areas that have wilted or for prematurely ripening plants within canola stands that are otherwise healthy. Post-swathing (within approximately 3 days after swathing) is another ideal time for disease scouting. Prematurely ripening areas may be indicators of diseases that restrict water and nutrient uptake by plants. It is important to accurately identify what is causing the damage and properly document the information for future reference. Identification of clubroot will allow growers to take steps to limit soil (and associated spore) movement to other fields through equipment sanitation. Fields with alternaria will be poor candidates for delayed swathing and should not be straight combined as pods will be prone to shattering.
In normal years, the optimum stage to swath for both yield and quality is up to 60% seed colour change on the main stem. However, as the season progresses, there are an increasing number of reports of crops that were planted early where the seeds are all firm and intact for a week or longer, but little to no seed colour change has taken place. If the short-term weather forecast remains cool and/or cloudy with a high risk of frost then it may be better to begin swathing these fields as early as 10% seed colour change. The risk of yield loss from early swathing will be reduced if all the seed is firm, but the risk of grade loss from frost damage if the crop is left standing is relatively high. In many of these cases, the crops have been in the ground for up to 120 days and the seeds may be physiologically mature, although outside seed colour remains green. Growers considering early swathing to avoid or reduce green seed levels from frost need to remember that swathing prior to 15-20% seed colour change will likely reduce some yield potential. Also, the canola has to dry down sufficiently to reduce freezing damage and the canola may need to be swathed for several days before this stage is reached, especially if conditions are cool and damp.
When assessing seed colour, also check seed firmness. Under cool conditions, seeds near the top of the plant may continue to fill and become firm before the lower seeds begin to turn colour. Avoid swathing when a significant portion of the seed in the top pods and side branches remain translucent and watery. Also, be conscious of disease-infected or hail-damaged fields and do not let the premature ripening of the diseased or damaged plants influence the time of swathing. Realize that the bulk of the yield is likely still coming from the healthy plants. A better strategy than swathing early to capture more yield is to swath during dew periods to prevent shattering of the damaged plants. To learn more about proper field assessment, refer to the revised Canola Council publication "Canola Time of Swathing Guide" or visit the Canola Council website: http://www.canola-council.org/pub_swathing.html
Remember that under cool and wet conditions, swath curing will take longer than usual. Expect to have the crop in the swath for at least three weeks to allow for curing and as much de-greening as possible before combining. It is important to utilize swath rollers to anchor the swaths into the remaining stubble in order to limit the potential for wind damage to the swaths. However, growers are encouraged to avoid excessive packing from swath rollers, allowing as much air movement through the swath as possible to facilitate curing and limit disease spread in the swath.
More growers are considering straight cutting their canola this year. For further guidelines and tips about straight cutting refer to last week’s Canola Watch report at the following link:
http://www.canola-council.org/canola_watch_report_2007_18.html#straight
There have been some reports of green seed in canola (3-8% at 7-14 days after swathing) this past week. Given that we are still early into the harvest season, growers should leave their canola in the swath for a longer period of time to allow for more curing, and give rainfall or heavy dews a chance to reactivate the de-greening enzymes within the seed.
The hot and dry weather of this past season has resulted in stubble remaining green and in some cases, re-growing after swathing. In these situations, monitor for the presence of any green material that may be mixing with the grain while combining as this material may create a potential hot spot within the bin. This green material is likely to cause pockets of localized high moisture within the grain mass in storage, so it is important that the grain is adequately conditioned.
For those faced with green material growing through the stubble and into the swaths, combine as soon as possible, after the seed has adequately cured. Although this may not eliminate problems with green and wet plant material mixed with the grain, it can reduce the amount of contamination. Do not consider using unregistered herbicides to kill this green material as this will possibly leave residues on the grain, which may endanger some of our markets.
There were more reports of wind blown swaths this week. Usually the worst affected fields were swathed at right angles to prevailing winds. Growers with fields still to swath are encouraged to swath their fields parallel to prevailing winds to reduce the risk of wind blown swaths and resulting crop loss from shelling. Cut as high as possible (just below the lowest pods) and consider using a swath roller to help anchor the swath into the stubble.
At this time of the year, as growers prepare bins for storage, it is important to note that oilseed crops including canola can absorb malathion from bin surfaces, and the resulting residues have been found in crop delivered to elevators. Therefore, Do NOT use malathion to treat bins destined to store canola from the upcoming harvest. Refer to the following link for further information: http://www.canola-council.org/pesticide_link2.html
There have been some questions from growers wondering about mixing diatomaceous earth products such as “Protect-It’ or ‘Insecto’ into their canola for insect control. These products should only be used to treat bin floors and walls prior to storing grain, as they are not registered for use on stored canola.
For those growers combining canola during warm temperatures, canola storage can also be a concern even at seed moisture levels of 8% or lower. This can be compounded by the presence of insects such as grasshoppers and ladybugs in the grain. Be aware that canola binned at high temperatures may be susceptible to heating and spoilage even though it may test dry, particularly if it contains green material such as weed seeds, chaff or insects. Use aeration to bring down the temperature of the binned canola. For more information on safe storage and conditioning canola, check the following link: http://www.canola-council.org/media_aug2306.html
Post-harvest weed control may be an option this year due to the early harvest in some areas. Post-harvest weed control will help maximize canola returns next year by controlling hard to kill weeds such as dandelions. Research conducted at the University of Manitoba indicated that superior control of dandelions is achieved with fall herbicide application instead of spring control. Managing weeds after harvest will help limit weed seed populations in the following years. A few tips for maximizing post-harvest weed control are:
- cut stubble high to leave as much plant material as possible,
- spread straw and chaff adequately to leave plants exposed and
- spray when new plant growth is evident or when leaves are present.
Fall soil testing is a very useful tool in order to assess required fertility levels for next year. The proper sample time in the fall is after the soil surface temperature drops to less than 7°C. At this temperature, soil processes such as mineralization (breakdown of soil organic matter into plant available nutrients) that cause changes in soil nutrients proceed quite slowly and therefore changes in plant available nutrient levels are normally not great. By sampling in the fall, there is sufficient time to properly process samples, provide test results and recommendations and develop a fertilizer program for this fall or next spring. It allows more time to order fertilizer, to take advantage of typically lower fall fertilizer prices and spread the workload out over two seasons.
This is the final Canola Watch report for the 2007 season. We hope you have found these weekly reports informative, interesting and useful. We will email you a survey soon so you can tell us exactly what you think of Canola Watch. We want to do even better next year! The 2007 series is posted on the Canola Council website at http://www.canola-council.org/watch_2007.html.
To add to the value of Canola Watch reports, the Canola Watch Team will be developing a follow-up exam for subscribers who are Certified Crop Advisors interested in receiving CCA education credits. We will be emailing out the notice within approximately one month.
Direct questions regarding this report to John Mayko, Senior Agronomy Specialist, Parkland West (West Central AB), 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 agronomy specialists or provincial oilseed specialists:
Derwyn Hammond, Agronomy Specialist, Manitoba, hammondd@canola-council.org, 204-729-9011
Arvel Lawson, Manitoba Agriculture, Food & Rural Initiatives, Arvel.Lawson@gov.mb.ca, 204-745-0340
David Vanthuyne, Agronomy Specialist, Eastern Saskatchewan, vanthuyd@canola-council.org, 306-946-3588
Jim Bessel, Senior Agronomy Specialist, North-central/eastern 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, Agronomy Specialist, Parkland East (East Central AB & NW SK), moiseyd@canola-council.org, 780-645-3624
Matthew Stanford, Agronomy Specialist, Chinook (Southern AB & SW SK), stanfordm@canola-council.org, 403-758-6660
Anne Vos, Acting Agronomy Specialist, Peace Region, av@summit-ag.com, 780-835-4632
Murray Hartman, Alberta Agriculture, Food & Rural Development, murray.hartman@gov.ab.ca, 403-782-8024
Kerry Clark, BC Ministry of Agriculture and Lands, Kerry.Clark@gov.bc.ca, 250-784-2559
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.