Canola Watch Reports

2007 Canola Watch Reports

#7 Western Canada – June 13, 2007

In this issue:
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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 is virtually complete across most areas of the prairies. Some canola seeding continued last week in areas including northern Saskatchewan, central Alberta and the Peace region. However, there are still likely to be a substantial number of unseeded acres in northeastern Saskatchewan, west-central Alberta and the Peace because of wet field conditions.

Stress from excess moisture continues in eastern Manitoba, parts of eastern and northeast Saskatchewan and west-central Alberta between Didsbury and Lacombe. Excess moisture results in a lack of oxygen in the root zone that causes changes in plant colour such as yellowing or purpling, stunted growth, or premature bolting (small and spindly canola plants that are starting to bolt). The degree of damage will depend on several factors including crop stage, soil type and texture and time spent under water. For further information regarding the effects of excess moisture on canola growth, refer to the following link: www.canola-council.org/excessmoisture.aspx.

Frost was reported in many areas including Treherne and Somerset Manitoba, Tompkins, Langham, Biggar, Neilburg, Battleford and Glaslyn Saskatchewan, in many parts of north-central Alberta and in the Peace region between Manning and La Crete. Some reseeding of damaged canola has occurred in these regions. However, due to the lateness of the season, reseeding at this time should only be considered if there has been damage affecting widespread field areas resulting in a substantial reduction in the number of viable plants. In that case, affected fields should only be reseeded to early maturing canola varieties such as B. rapa (Polish) or to early maturing cereals such as barley. Refer to the Canol@Fact “Tips for assessing spring frost damage in canola” for more information: Canola Assessing Spring

Remember, as long as the central growing point of most of the plants remains green, the likelihood of crop recovery is high.

Prolific weed growth continues in many areas due to the favourable moisture conditions. Herbicide application has been delayed in many areas due to high winds and/or frequent rainfall. Weed growth is especially heavy in direct seeded fields that have not received a pre or post-seeding burn-off application. In these cases, it is especially important for growers to do an early in-crop herbicide application. Control of early germinating weeds is important in minimizing moisture and nutrient loss and reducing weed competition to allow establishment of a healthy and competitive crop stand. However, because many areas have also experienced frost and standing water, it is important that growers give the crop some time to recover from these stresses before applying another stress in terms of herbicide application. These stress conditions also often lead to poor weed control as well. On the other hand, the recent warm and humid weather in some areas can be good for weed control, but it will also result in increased herbicide uptake by the crop. Some issues with reduced crop tolerance and surfactant burn have already been reported in a few fields in Manitoba.

Growers are strongly encouraged to assess the number, growth stage and types of weeds present prior to herbicide applications. Also, remember to read herbicide labels. With several herbicides available in various formulations (e.g. glyphosate), as well as various possible tank-mix combinations, it is important that the correct rate and timing of product(s) are applied to ensure good weed control and crop tolerance. Also, ensure that proper tank cleanout procedures are followed when switching herbicides and crops to reduce chances of subsequent crop injury. For further comments including specific weed-herbicide recommendations, tank-mix options and spraying tips, refer to last week’s report at: www.canola-council.org/Canola_Watch_Report_2007_06.html

Herbicide residue symptoms have been reported in Manitoba on susceptible crops affected by the drought last summer as well as in the north Peace region near La Crete. To assist in identification of herbicide residues on canola, refer to the following Canola Council Herbicide Residue Injury Guide at: www.canola-council.org/PDF/toolbook.pdf

Early seeded crops in many areas have received their first herbicide pass and growers are considering a second application. Prior to automatically applying the second herbicide pass, first consider whether or not the second pass is warranted given the remaining weed pressure. Also, if the canola canopy is starting to reach complete ground cover, the herbicide may not reach targeted weeds. Growers are cautioned when applying late first applications or the second applications of herbicides when the crop is in the bud stage; late spraying could potentially lead to crop stress and blanks on the main stem. Refer to the attached Canol@Fact (Timing is Critical to Profitable Weed Control. PDF) for more information on weed control timing including second applications and to the following Canol@Fact at www.canola-council.org/PDF/May24_How_Many_Weeds.pd for more information regarding weed populations and economic thresholds.

Crop development varies widely based largely on when the crop was seeded. Some earlier seeded crops in Manitoba, north-western Saskatchewan and southern Alberta are at the bolting stage, whereas crops in other areas seeded within the last week or two have not yet emerged. Areas of north-central Alberta that were seeded later or were broadcast seeded continue reporting patchy emergence, especially on hill tops and solonetzic areas.

Remember to keep scouting fields on a regular basis to detect crop development problems early. Consider establishing a scouting tramline by driving an ATV in an 'X' or 'W' pattern in the field to establish pathways for crop scouting. This will allow for easier scouting with minimal trampling at later crop stages, especially once the crop is blooming.

Cutworms continue to be reported near Hartney and Manitou MB, and Ituna SK and crop damage similar to cutworms has been reported near Neerlandia, AB. Be especially vigilant in areas that had cutworm damage last year. Before considering control, check the size of cutworms and whether they are actively feeding. Cutworms nearing 38 mm (1.5 inches) long are not good candidates for control, since these worms are close to pupating, so be sure of the size before considering control measures. Also, cut open the abdomen of any located cutworms. Green material in the abdomen indicates active feeding which makes these worms favorable for control, whereas the absence of green material may indicate that these worms are close to pupating. For more information on cutworms, refer to the May 30 Canola Watch report: www.canola-council.org/Canola_Watch_Report_2007_05.html

Flea beetles continue to be reported throughout many areas. Some insecticide spraying has occurred, with the worst damage being reported in fields with tight canola rotations, no insecticide seed treatments used, or when the seed has been in the ground for a long time before emerging. For help in assessing the amount of damage noted refer to the following link: www.canola-council.org/fleabeetlemonitoring.aspx. Agronomists are encouraged to note whether the flea beetles are two-striped or cruciferous. Check the following link for help in identifying the different species: www.canola-council.org/fleabeetleident.aspx . If noted, please pass this information on to your local Canola Council agronomist. For more tips on scouting for flea beetles, refer to a previous Canola Watch report at: www.canola-council.org/Canola_Watch_Report_2007_04.html

Cabbage seedpod weevils have been noted throughout southern Alberta between Medicine Hat and Lethbridge in some canola fields as well as on volunteer canola and cruciferous weeds. Early seeded fields are at most risk at this time of year and should be scouted frequently, especially as the crop starts to bud, bolt and flower. For more tips on scouting and controlling cabbage seedpod weevil, refer to the following links:

Gopher (Richardson's ground squirrel) damage continues in areas of southern and north-western Saskatchewan. Some reseeding of fields has occurred as a result of the damage. Refer to the following AAF link for further information on management and control: www1.agric.gov.ab.ca

Top dressing of nitrogen and/or sulphur is being considered by many growers especially in northern and eastern Saskatchewan. This practice should be considered by growers who were conservative with their initial fertilizer applications for this crop or were unable to apply sufficient fertilizer at the time of seeding. Top dressing may also be considered in areas with excess moisture that may have experienced substantial nitrogen losses from saturated soils in low-lying areas. If the excess water recedes fairly quickly and the canola recovers, growers may need to consider top dressing additional nitrogen to compensate. Growers concerned about the nutrient status of their crop should consider tissue testing, but for recently flooded canola it is important to remember to allow for the plant to recover and growth to stabilize before tissue testing takes place. Topdressing N and S fertilizer can be successful up to the bolting stage--as long as rainfall occurs to move the fertilizer into the root zone, but in general, the sooner the fertilizer application, the better the chances of receiving an economic crop response. Ensure rates and field conditions are appropriate to minimize any detrimental effects to the crop, such as leaf burn. If considering products like fines, ensure the application equipment available will allow consistent coverage.

Soil moisture conditions continue to range from fair to excessive across most of western Canada. Variable precipitation was received across many parts of the west. Heavy thundershowers and hail were experienced in parts of central Alberta including Hairy Hill, Lougheed and Stony Plain, although topsoil moisture conditions continue to deteriorate around Vegreville. Areas of standing water and/or saturated soils continue to be a problem in parts of eastern Manitoba including areas around Lac du Bonnet, LaSalle, Domain, Brunkild and Sanford and in central Alberta between Olds and Lacombe.

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: www.agr.gov.sk.ca

Additional moisture information for Alberta is available from Alberta Environment at: www3.gov.ab.ca

Direct questions regarding this report to John Mayko, Senior Agronomist, 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 agronomists or provincial oilseed specialists:

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.