Too Dry, Just Right and Too Wet

Relatively cool growing conditions prevailed again last week across most of western Canada. Overnight lows were cool with single digits with freezing temperatures (-1oC) reported near Maidstone, SK and Beaverlodge, AB Tuesday and Thursday mornings, respectively. The risk of an early fall frost and its impact on crop quality continues to be one of the greatest concerns. However, the cool temperatures at flowering have resulted in canola that has branched and podded well, creating the potential for average to perhaps even above average yield in some areas where moisture has been adequate. Timely rains fell in northwest and central Manitoba, eastern and northern Saskatchewan, and southwest of the Highway #2 corridor in central Alberta, and as well as in the Peace region of Alberta and BC. Much of the canola crop in these areas is coming out of flower with good pod set and the recent rains should help with seed fill. Dry pockets continue near Edmonton-Camrose-Vegreville areas and south of Unity to Kindersley, Saskatchewan and across the Alberta border to an area around Oyen. Drought stress symptoms are evident on the crops with large ground cracks obvious. In the driest areas, canola is being silaged for greenfeed or sprayed out to conserve fertilizer applied as crops continue to be written off by AFSC (provincial crop insurance). Parts of eastern and Interlake regions of Manitoba continue to battle excess moisture with a small band of showers dumping another 1 to 2 inches on an already water-logged area.

Maps of current moisture conditions in western Canada from PFRA are available at:
http://www.agr.gc.ca/pfra/drought/prpay09_e.htm
http://www.agr.gc.ca/pfra/drought/prpgs09_e.htm
Additional moisture information for Alberta is available from Alberta Environment at:
http://www.environment.alberta.ca/forecasting/data/precipmaps/weekly.pdf

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Turn up the Heat, Please

Crop development ranges from late bloom (70%) in the late and re-seeded fields to about 10 to 20% colour change in the earliest fields. The very earliest fields in southwestern Manitoba and eastern Saskatchewan are about a week to 10 days from swathing, with the majority of the crop about two to three weeks from swathing. Crop development continues to lag behind the long term average (about one to two weeks behind). Most areas would like to see five to ten days of significant heat to hasten crop maturity and the absence of the first significant fall frost until at least mid to late September.

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 Ministry of Agriculture is available at:
http://www.agriculture.gov.sk.ca/crprpt090806
The latest crop report from Alberta Agriculture and Rural Development is available at:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/sdd4191#2009
The following maps show growing degree days accumulating across western Canada this growing season: http://www.agr.gc.ca/pfra/drought/prtgdd_e.htm

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Hail Damage – Getting Too Late to Recover

Hail was reported near Chaplin, SK last week. The hail damage from thunderstorms 10 days ago in Alberta has been quantified and one million acres of cropland are affected, with damage to the canola within the affected area generally ranging from 20% to 60%. It is likely getting too late in the growing season for canola plants to compensate and recover from severe hail damage. Mid-season hail is also a concern for disease access. The hail wounds on the plant can provide points of entry for disease pathogens such as sclerotinia stem rot, alternaria black spot or blackleg if environmental conditions have been conducive to spore production and disease development. More information about hail damage to canola is available at the following link: http://www.canola-council.org/chapter5.aspx.

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Lygus Numbers Variable – Scout Thoroughly

Lygus populations continue to be monitored in the Peace Region of Alberta and BC and in southern Alberta. Populations are variable as many fields are exceeding economic thresholds (as much as three to four times higher) and still many others remain below threshold levels. Each field must be assessed for lygus on an individual bases. Scout all fields to determine the population levels in each individual field. Scout thoroughly as well, as high populations requiring control have been present only on field edges (not throughout the field) in some instances. When scouting for lygus it is important to note the stage of the crop and insect. Young nymphs will do very little damage compared to later instars and adults. Later maturing fields may still be at significant risk but fields that are nearing maturity may escape the damage. Fields nearing maturity will be less vulnerable because pod texture becomes rubbery and tougher for lygus bugs to pierce. For more information on lygus monitoring refer to the following interview with Erin Brock, Peace region agronomy specialist on the ACPC website: http://www.canola.ab.ca/agronomic/grow_with_canola.html

Young lygus nymphs are pale green and resemble aphids but have five small black dots and no cornicles. Adult lygus bugs are pale green to reddish brown/black with a “V” mark one third of the way down their backs. Lygus cause damage by feeding on leaves, stems, flowers, and pods, resulting in flower blasting and shriveled seeds. There is a range for the economic threshold depending on crop stage and price. More information is available at the following link: http://www.gov.mb.ca/agriculture/crops/insects/fad12s00.html.

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Pay Attention to PreHarvest Intervals and Product Registrations

The preharvest interval (PHI) refers to the number of days that the crop should not be harvested after applying a pesticide. Harvest in this context means cutting or swathing. If the crop is harvested before the indicated interval has elapsed, there could be unsafe or unacceptable residues of the pesticide remaining in or on the harvested seeds. Preharvest intervals are listed on the labels of pesticides and under the ‘Restrictions’ section of individual product descriptions in a current provincial Guide to Crop Protection. When pesticide applications are being considered, take note of the required preharvest interval and allow for that time period before harvest. Also, ensure that the product is registered for the intended use and registered to be used on the crop at that stage. Following pre-harvest intervals is critical to keeping all canola Export Ready.

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Affected Patches Appearing – Find out Why

At this time of year (as the canola crop finishes flowering and begins to pod), stressed or affected patches often appear within the field. These patches are usually most noticeable because they started flowering at the same time as the rest of the field but are now coming out of flower sooner. If possible, mark these suspicious patches so they can be examined more closely to determine what is happening with the canola crop. Are these stressed patches located on knolls (e.g. lacking moisture sooner or could soil fertility be playing a role)? Are root maggots present? Pull plants with roots intact and check for root maggots. Plant disease symptoms can also begin to appear at this time so take a closer look to determine if blackleg or sclerotinia stem rot are present. Clubroot disease may be another potential explanation. In the first few Canola Watch issues this spring, it was reported that a soil test from west-central Saskatchewan had shown the potential presence of the clubroot pathogen’s DNA. Further testing was being conducted to confirm the results. SaskCanola recently reported that the DNA diagnostic test and a canola plant bioassay confirmed that trace levels of the clubroot pathogen (Plasmodiophora brassicae) were present in that soil sample. More information is found in the press release issued at: http://www.saskcanola.com/news/2009-0721-clubroot.html

While scouting, it is important to follow field entry protocols to maintain proper sanitation and limit the spread of clubroot. More information on sanitation guidelines is available at the following link: http://www.canolacouncil.org/clubroot/docs/field_entry_1.pdf and more general information on clubroot is available at http://www.clubroot.ca/

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Harvest Approaching – Start Planning Now

During pod fill is a good time to assess yield potential leading up to harvest. The variable staging this year has not evened out and will require more management at harvest. It may be beneficial to mark or section off fields based on similar staging and yield potential. Know where the greatest yield potential is within the field and plan to focus on protecting it the most. The greatest yield potential includes the plants with most seeds but also earliest maturing to escape a fall frost. Yield potential can be determined by counting the number of pods on a plant and the number of seeds per pod. Pods can be plucked and held up to the light to determine the number of seeds within the pod. Is the staging so variable that a desiccant may be needed to hasten maturity on the latest plants? Would swathing be better than straight cutting or vice versa? Is there a lot of green weed growth that will require a pre-harvest application?

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Variable Stages Benefit from Pod Sealant?

With the variable stages in this year’s canola crop, questions about the benefits of applying a pod sealant are surfacing. Pod sealants are relatively new to the Canadian marketplace and limited scientific research has been conducted with these products under western Canadian conditions. These products are designed to reduce shattering losses by preventing the pods from splitting open during ripening. As with any new agronomic tool where information on its performance under our environmental conditions is limited, it is always a good strategy to start small in order to learn what works best. Part of this learning should involve leaving check strips of an untreated area. By conducting your own on-farm experiment, you will be able to determine whether the application was beneficial and worth the investment.

Most of the questions regarding these products have focused on application timing. The information provided by the companies suggests that the majority of the pods should be changing colour from green to yellow but the pods should still be pliable enough to fold over without splitting open. However, there needs to be enough seed colour change within the pods to allow curing and harvesting within the window of protection provided by the product you are using. The best advice is to consult with your company representative on the ideal timing for your fields. One other general tip that applies to these products is to stick with the high water volumes recommended by the company. Thorough coverage of all the pods is very important because these products form a physical coating to seal the pods against splitting open.

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Anchoring Short Canola Stands

Questions about swathing this year’s crop with low plant stands and shortened crop height are starting as the ability to anchor the swath to the stubble will likely be hampered. To reduce potential losses from swaths blowing, keep the following recommendations in mind:

• Swath parallel to the typical prevailing winds in the area
• Cut the plants as high as possible, just below the lowest pod
• Using a properly adjusted swath roller, push down the swath so that the edges are nestled into the stubble. Because the swath will be on or close to the ground, curing and/or dry down time may take longer.

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Don’t be Tempted to Swath Too Early

As the calendar progresses and the risk of fall frost increases, it may be tempting to swath earlier than optimal. Growers must ensure that seed colour change is occurring when assessing the proper time to swath. Do not use plant or pod colour to gauge proper timing because some pods will appear ripe on the outside before the seeds are mature. Some varieties will show pod colour change long before the seeds do, while the opposite is true of other varieties. Open up pods on the main stem and look at the colour of the seeds to accurately assess swathing timing. Research indicates that the optimum stage to swath for both yield and quality is up to an average of 60% seed colour change (SCC) on the main stem.

However, for growers faced with uneven maturity within fields, it may not be possible to swath all of the crop in the 50-60% SCC window. In situations where uneven maturity is the problem, the best approach is to swath when the most mature plants are close to 60% SCC, provided that the least mature plants are showing some seed colour change at the base of the main stem and that seeds in the upper pods (and branches) are dark green and firm (if maturity varies more than this consult the link regarding multi stage crops below). This will minimize yield loss from seed shrinkage and improve the odds that the seed will cure, although it will likely take longer and may require some more moist conditions. Swathing prior to 15 to 20% seed colour change will likely reduce yield potential and could contribute to green seed issues under hot and/or dry conditions.

More information is available on the "Canola Time of Swathing Guide" at the following link:
https://canola-council.merchantsecure.com/canola_resources/product12.aspx

More information on harvesting a multi-stage crop is available at the following link:
Harvesting Multi-Stage Crop

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Keep Malathion OUT of Canola Bins

As bins are prepared for the coming harvest, keep in mind that using malathion on canola seed or in canola storage bins will result in detectable levels of malathion residue because malathion has a strong attraction to the oil in canola seed. Consequently, malathion can move into canola seed from storage bin walls. Detection of malathion residue in canola seed above the allowable limit will result in rejected shipments and increased monitoring. DO NOT use malathion to treat bins destined to store canola. More information is available at the following link: http://www.canola-council.org/pesticide_link2.aspx

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Questions & Contacts

Direct questions regarding this report to John Mayko, Senior Agronomy Specialist with the Canola Council of Canada at maykoj@canolacouncil.org, 780-764-2593.

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

Derwyn Hammond, Senior Agronomy Specialist Manitoba, hammondd@canolacouncil.org, 204-729-9011
Anastasia Kubinec, Manitoba Agriculture, Food and Rural Initiatives, anastasia.kubinec@gov.mb.ca, 204-745-5645
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
Venkata Vakulabharanam, Saskatchewan Ministry of Agriculture, Venkata.Vakulabharanam@gov.sk.ca, (306)787-4668
Doug Moisey, Senior Agronomy Specialist, East Central Alberta and Northwestern Saskatchewan, 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, 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:

Alberta Canola Producers Commission; Alberta Agriculture and Rural Development, SaskCanola, Saskatchewan Canola Growers Association, Saskatchewan Ministry of Agriculture, Manitoba Canola Growers Association, Manitoba Agriculture, Food and Rural Initiatives, Peace River Agriculture Development Fund, B.C. Ministry of Agriculture & Lands, Agriculture and Agri-Food Canada, and the Canola Council of Canada.

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