Canola Watch

2007 Canola Watch Reports

#5 Western Canada – May 30, 2007

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

Canola seeding nearing completion despite weather setbacks
Soil moisture conditions remain good to excessive
Continuing rains causing stress in canola fields
Consider top-dressing fertilizer
Frost damaged canola is recovering well
Seeding still delayed?  Follow these tips.
Seed registered varieties only
Reassess variety suitability
Broadcast seeding not generally recommended
Check for soil crusting & compaction
Good control of early weed growth is key
Remember to read herbicide labels
Scout fields to check germination
Cutworms showing up already
Flea beetles reported
 
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 progress remains variable across the prairies. Seeding is nearing completion across southwest, central and eastern areas of Manitoba and most southern parts of Saskatchewan and Alberta. Seeding progress continued to be delayed by rains in all provinces and snow in west-central Alberta between Calgary and Ponoka. Areas furthest delayed include northeastern Saskatchewan between Melfort and Carrot River, central Alberta between Olds and Ponoka and parts of the Peace region including Rycroft, Falher and Debolt. There continue to be reports of some growers returning their canola seed for earlier varieties and switching to alternate crops, principally barley in many areas and fescue in the Peace region.

Soil moisture conditions continue to range from good to excessive across most of western Canada. Variable precipitation (from trace to 175 mm) was received across many parts of the west, with many areas of Manitoba and northern and eastern Saskatchewan receiving at least 50-75 mm. Areas reporting standing water increased over last week, including parts of central and eastern Manitoba, northern and eastern Saskatchewan, central Alberta north of Calgary, and many areas of the Peace region.

For current maps of moisture conditions from PFRA for western Canada, check the following links for precipitation since September 1 and April 1 respectively:
http://www.agr.gc.ca/pfra/drought/prpay07_e.htm
http://www.agr.gc.ca/pfra/drought/prpgs07_e.htm

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/crprpt070527.asp

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

Continuing rains in parts of eastern and northeast Saskatchewan and central and eastern Manitoba are causing stress from excess moisture. 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: http://www.canola-council.org/excessmoisture.aspx.

Areas with excess moisture may also experience 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. As well, growers who were conservative with their initial fertilizer applications for this crop or were unable to access sufficient fertilizer at the time of seeding and now find favorable to excellent growing conditions may also consider topping up their nitrogen and sulphur rates by top dressing. 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. Remember that 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. This helps alleviate any deficiencies and ensures optimum yields if sub-optimal fertilizer rates were applied or nutrient losses have occurred. Also, 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.

More frost was reported in many areas across the west this past week, with some areas reporting lows as cold as -4 degrees C. Damage to emerging canola is mostly reported to be light so far, due to the fact that most crops had not yet emerged, but some damage to early seeded canola was reported in western Manitoba, with reseeding in a few cases. However, in many affected fields the canola plants appear to be recovering, with new growth at the growing points. The amount of frost injury will depend on moisture conditions, duration of the frost and coldest temperature reached, rate at which thawing occurs, the growth stage of the plants, trash cover and the amount of cold temperature hardening the plants have experienced. A light frost that wilts the leaves, but does not cause any browning, will not severely damage the plants. Some discolouration of the leaves may occur, usually a yellowing or whitening especially under drought conditions. Refer to the Canol@Fact “Tips for assessing spring frost damage in canola” for more information: http://www.canola-council.org/PDF/may5_Canola_AssessingSpring.pdf#zoom=100

Remember, that a proper assessment of frost damage cannot be made for several days--until it can be determined whether new growth is appearing from damaged plants.

Although seeding remains delayed in many areas of Saskatchewan and Alberta compared to the past few years, growers can still take steps to speed maturity and offset some of these delays. The combination of good to excellent soil moisture combined with favourable soil temperatures is ideal for rapid and even emergence as long as the proper seeding techniques are used.

• Seed shallow to facilitate rapid emergence, ideally at a depth of ½ to ¾ of an inch.
• Keep any pre-seeding tillage shallow to help maintain the seedbed firmness and moisture.
• Consider increasing seeding rates slightly to reduce individual plant branching. Make sure that seeding rates are high enough to establish the target of 7-14 plants/ft2.
• Apply recommended rates of phosphorus fertilizer for the “pop-up effect” in cooler areas to ensure more uniform crop maturity, but watch seed-placed fertilizer rates to avoid seedling toxicity.
• As well, consider backing off nitrogen rates slightly to reduce the delay in maturity at the end of the season.

With ongoing seeding delays in some areas producers may be considering switching variety choices.  Limited supplies of certified seed of early napus and rapa varieties may make using bin run seed more tempting.  Make sure you are not choosing a de-registered variety.  There are no glyphosate tolerant Polish canola options.  Also, if you are using saved seed, try to get a germination test before you head to the field, and save a sample of the seed.  It is also important to use a seed treatment registered for use on canola.  No seed treatments containing lindane should be used.  Using de-registered varieties or seed treatments jeopardizes canola markets.  For more information look up the Canola Export Ready program on our website http://www.canola-council.org/export_ready.html  or call toll-free 1-866-834-4378.

Growers who still have significant acreages of canola left to seed need to reassess 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.

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 to determine the average first fall frost date:
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/agdex10

The continued delay in seeding progress has producers considering 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. Refer to the previous crop watch report for further tips on enhancing successfulness of broadcast seeding: http://www.canola-council.org/Canola_Watch_Report_2007_03.html

Soil crusting and compaction continue to be reported in a number of areas including southwestern and central areas of Manitoba, eastern and northern Saskatchewan and parts of the Peace region. The majority of crusting cases appear to have occurred after heavy rains or seeding and packing of wet soils. The larger, deeper and denser the crust, the more difficult it will be for the seedlings to emerge. Growers should be patient to evaluate the extent of the crop’s ability to push through the crust prior to taking any remedial action. If hot and dry weather occurs after the crust develops, then often the crust becomes harder and more difficult to penetrate through. However, if some rain occurs afterwards, then the rain will tend to soften the crust and then the seedlings can emerge to the surface. Although remedial action such as light harrowing has sometimes been used to break up the crusting, growers should be very cautious of this practice especially if the seed is shallow and if germination has already occurred. Reduced tillage practices and keeping crop residues near the soil surface are useful in reducing the occurrence and severity of soil crusting.

Weed growth continues in many areas due to the favourable moisture conditions. In many areas of Manitoba, the combination of early seeding and the lack of pre-emergent burn-off applications have led to many fields experiencing advanced weed growth compared to the crop stage, especially grassy weeds like wild oats. 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 of these 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. Poor growing conditions also often lead to poor weed control as well. Refer to the attached Canol@Fact (Timing is Critical to Profitable Weed Control.pdf) for more information on weed control timing.

Growers are strongly encouraged to assess the number, growth stage and types of weeds present prior herbicide applications. Also, remember to read the herbicide label. With several herbicides available in various formulations (e.g. glyphosate), it is important that the correct rate of active ingredient is applied to ensure good weed control and crop tolerance.

For those growers relying on post-seeding, pre-emergent burn-off applications, keep in mind that many areas are reporting canola emergence within a week of seeding, due to ample moisture and warm soils. Monitor carefully for emergence prior to spraying to avoid crop damage.

Slow emergence and lagging early growth open the door for seedling diseases to affect the crop. Also, the delays in emergence may have affected the duration of protection following emergence for the seed treatment products. Remember that the time of protection is usually from the day of planting, not the day of emergence. 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 Canol@Fact “Factors affecting canola survival for seeding to 21 days after emergence” for more information: http://www.canola-council.org/PDF/seed_to_21days.pdf#zoom=100

When scouting fields with any stand establishment problems, check for the presence of the blue seed coat, at or near the root of the seedling or the depth of seeding. This will indicate whether the affected plants are from the current year’s seed, or whether the plants may be volunteers from previous years.

Cutworms have been noticed in parts of southwestern Saskatchewan near Stewart Valley. Be especially vigilant in areas that had cutworm damage last year. Scout canola fields from early-May to mid-June to determine whether areas with no seedlings have resulted from cutworm damage. Check the edges of bare areas for cut-off plants. Wilted, dead or cut-off plants (weed or crop seedlings) will be seen. Dig around the roots of these plants for cutworms. To collect cutworm larvae, a garden trowel and a soil sifter are useful tools. Cutworms may be found in dry surface soil down to about 5 cm (2") below the soil surface. The small, worm-like larvae curl up or attempt to hide in the debris. Cutworm control may only be necessary in small areas of the field, when bare patches appear and large numbers of the insect are still actively feeding. Be sure to note the size of the larvae you see in the field. Large specimens (over 25 mm long) will soon stop feeding and pupate and are also more difficult to kill. If cutworms are still small, and numerous enough to warrant control, apply one of the registered insecticides. Apply surface treatments in the evening, preferably under warm, moist conditions, as cutworms are active at night and these treatments will only control surface-feeding larvae. Do not disturb the soil for five days after treatment. Also refer to the Canol@Fact on cutworms: http://www.canola-council.org/PDF/May4_2FS_Controlling_Cutworms.pdf#zoom=100

Flea beetles continue to be reported in parts of southwestern, central and Interlake regions of Manitoba, in Saskatchewan near Indian Head, Kipling, Landis and Dorintosh and in Alberta near St. Albert. Although most of the reports are on volunteer canola and wild mustard, early seeded fields have begun to emerge, so pay particular attention in these cases, especially on fields with tight canola rotations, where no insecticide seed treatment was used or when the seed has been in the ground for a long time before emerging. 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:  http://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 last weeks Canola Watch report at: http://www.canola-council.org/Canola_Watch_Report_2007_04.html

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 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:

Derwyn Hammond, Agronomist, 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, Agronomist, Eastern Saskatchewan, vanthuyd@canola-council.org, 306-782-7799
Jim Bessel, Senior Agronomist, 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, Agronomist, Parkland East (East Central AB & NW SK), moiseyd@canola-council.org, 780-645-3624
Matthew Stanford, Agronomist, Chinook (Southern AB & SW SK), stanfordm@canola-council.org, 403-758-6660
Anne Vos, Acting Agronomist, 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.

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