Canola Watch
2006 Canola Watch Reports
Canola Watch Report No. 9 Western Canada – June 21, 2006
In this issue:
(click the bookmarked links below to move to specific sections of this report)
Soil moisture ranges from dry to excess
Weeds growing rapidly, crop stage too late in some cases
Leaf bronzing from surfactant burn
Hail season and damage starting
Nutrient deficiencies showing up
Scout canola fields regularly
Wirestem on later seeded and wet fields
Take part in stand establishment survey
Assess sclerotinia risk
Flea beetles down but not out on late seeded canola
Root maggots showing up in Alberta
Bertha armyworm traps set
Don’t confuse beet webworm with bertha armyworm
Grasshoppers show up in Manitoba
Cabbage seedpod weevils reported in southwestern Saskatchewan
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
Soil moisture conditions continue to range from fair to excessive across western Canada. Precipitation this past week ranged from trace amounts to over 100 mm. Areas of northwestern Manitoba, east-central and northern Saskatchewan and southwestern Alberta remain wet. However dry areas are developing in parts of central Manitoba and the Interlake and the BC Peace region remains dry with the lack of recent rain. Although not critically low, rainfall will be needed soon, especially as early seeded fields approach the bolting and flowering stages.
For current maps of moisture conditions from PFRA for western Canada, check the following
links for precipitation from September 1 to June 19 and April 1 to June 19 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/pa_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/crprpt060618.pdf
Additional moisture information for Alberta is available from Alberta Environment at:
http://www3.gov.ab.ca/env/water/WS/data/precipmaps/weekly.pdf
Crop development remains good to excellent in most areas. Heavy weed growth continues in most areas, and spraying delays due to rains and wet fields continue to create problems in some areas. Some earlier seeded fields have already passed appropriate crop stages for spraying and there are reports of herbicides being returned for that reason. In addition, variable crop emergence especially in later seeded or re-seeded crops has lead to challenges regarding assessing the proper time for herbicide application. 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 required weed spectrum. 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. In addition, growers who may be pressed for time due to spraying delays should not forget proper handling techniques including proper sprayer cleanout protocols when changing chemicals as well as wearing proper protective clothing.
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
There have been numerous reports across the Prairies with regards to yellowing or bronzing of canola leaves, especially on Liberty Link canola. This may be caused by a number of factors including frost and herbicide surfactant burn, but this year the likely cause is surfactant burn from the herbicide (especially if reduced water volumes were used, or under optimum spraying conditions) or a combination of these factors. Large yellow or wilted areas are usually a sign of frost, while surfactant burn will usually show up as smaller round patches, similar to spray droplet deposition. This damage is usually minor, and the crop will outgrow the condition, especially under good growing conditions. To reduce the potential for this yellowing, target herbicide rates to weed size and spectrum and growing conditions and keep spray water volumes at recommended levels.
Hail damage was reported in parts of northwestern and southwestern Manitoba, in northeastern Saskatchewan and southern Alberta. Potential canola yield losses will depend on stage of crop and the severity of the damage. Hail damage can also allow points of entry for diseases such as sclerotinia stem rot, alternaria black spot and blackleg to infect canola plants. Further information is available at the following link: http://www.canola-council.org/stress_hail.aspx.
There have been reports of nutrient deficiencies developing in some fields in western Canada. The most common and easily recognized deficiencies are caused by lack of nitrogen or sulphur. The most accurate method of identifying nutrient deficiencies is by conducting a tissue analysis of affected plants and comparing them to tissue analysis of unaffected plants. Deficiencies may be caused by lack of actual nutrient applied prior to crop needs, by immobilization as heavy straw residues break down or by denitrification and/or leaching caused by the recent wet weather in some areas. Deficiencies may also be due to delayed access of nutrient bands by developing roots. Producers who are considering top dressing to correct deficiencies should refer to the following press release for more information:
http://www.canola-council.org/media_jun1705.html
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 at later crop stages, especially once the crop is blooming.
Wirestem continues to be reported in north-central Alberta on later seeded fields. Refer to the following link for more background information on seedling diseases:
http://www.canola-council.org/seedlingdisease.aspx
If you’re encountering stand establishment problems, we encourage you to refer to the following diagnostic template on 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.
Earliest seeded fields in many regions are reaching first flower, and many more will likely reach the bolting stage over the coming week if warm temperatures continue. This is the time to start scouting individual fields to assess risk for sclerotinia development and potential yield loss. The high levels of soil moisture in some areas combined with warm temperatures and crops at full ground cover may create conditions that are conducive to sclerotinia. However, with lower commodity prices many producers are questioning if spraying a fungicide to control sclerotinia will be worthwhile. Producers should carefully consider all of the factors highlighted in the sclerotinia stem rot checklist before making this decision. These factors include how heavy their crop canopy currently is, the amount of moisture received in the two weeks prior to flowering and potential for future rainfall, years since last host crop, disease incidence in the past, and the presence of apothecia in neighboring fields where host crops were grown previously. Target yield, fertility program and expected value of the canola crop are also points to consider.
A new publication called the Canola Disease Identification and Sclerotinia Risk Assessment Card is available to assist growers and crop scouts with this decision. It includes the stem rot checklist as well as pictures to aid in accurately identifying the apothecia of the sclerotinia fungus. A PDF version can be found at:
http://www.canola-council.org/PDF/canola_plant_disease_risk.pdf#page=1 or contact your local Canola Council agronomist. Also, for more information and tips on late season scouting for both diseases and insects, view the latest Canola Advantage press release at:
http://www.canola-council.org/about-us/media-news/media-releases/media-jun1906.html.
For the current list of recommended fungicides for sclerotinia control, refer to the 2006 Guide to Crop Protection:
http://www.gov.mb.ca/agriculture/crops/cropproduction/gaa01d01.html
Flea beetle activity has slowed down in most areas due to a combination of cooler and rainy weather. Although early seeded fields have outgrown any significant damage, later seeded or slower developing fields still remain at risk from damage. Refer to the May 25 Canola Watch report for further information on assessing flea beetle damage:
http://www.canola-council.org/about-us/media-news/media-releases/watch06-may25.html
and to the following Canol@Grow link:
http://www.canola-council.org/fleabeetlemonitoring.aspx
Root maggots have been reported in areas of northern Alberta, mainly in volunteer canola. The eggs are small (1 mm or 0.04" long), white and elongated. Eggs are deposited at or near the base of host plants, usually just beneath the soil surface. Occasionally eggs are also laid on the lower stems and leaves of canola plants. The larval stage is a small (6 to 10 mm or 0.2 to 0.4" long), white and legless maggot, similar in appearance to most fly maggots. This is the damaging stage of the insect that burrows its way through canola roots causing weak stems and allowing access for root borne plant diseases such as root rot. When searching for root maggot infestations at flowering, carefully pull or dig up several plants with the taproot intact. Carefully brush or rinse off the soil and inspect the root for maggots or for scars caused by maggot feeding. Check several plants in at least five or more locations. Cut into the root to look for maggot damage. There are no post emergent chemical controls for root maggot infestation. Refer to the following link for more information on root maggot:
http://www.canola-council.org/maggot.aspx
Bertha armyworm moth traps have been placed in canola fields throughout western Canada in the past week. Adult moth emergence will begin in the next couple of weeks, but very few have emerged so far. Growers in areas with high bertha numbers last year should be especially vigilant, as those regions are most at risk for high populations again this year. Hot spots last year include the Eaglesham, Falher and Wanham areas in the Peace, northeastern Alberta and northwestern Saskatchewan around Vermilion, Lloydminster and Maidstone, northeastern Saskatchewan, and northwest Manitoba. Growers should be aware of increasing moth numbers and watch for further information.
For more information on the bertha armyworm, refer to the following link:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/prm2521
For interpreting bertha armyworm trap numbers, refer to the following link:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/prm2526?opendocument
Proper identification of bertha armyworm larvae is important as they can be easily confused with beet webworm larvae, which have been reported in parts of north-central Alberta. As adult bertha moths are just beginning to appear, it is unlikely that any larvae found at this time will be bertha armyworm larvae. Mating will begin within a week of moth emergence, and egg laying will take place on the underside of leaves shortly thereafter. With average temperatures, eggs will hatch within a week. For more information regarding bertha armyworm and beet webworm identification, please refer to the Canola Scouting and Sweep Net Insect ID Card and the following links:
http://www.canola-council.org/bertha.aspx
http://www.canola-council.org/webworm.aspx
http://www.canola-council.org/PDF/sweepcard_pgs_04.pdf#page=1
Grasshoppers have now started to hatch near Melita in
southwestern Manitoba. Since there are many species of grasshoppers in western Canada, growers
need to be sure that the grasshoppers found during scouting are indeed pest species. Refer to
the following AAFRD and SAFRR links for further information on identification and management of
pest grasshoppers: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/for8648 http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex6463 http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex3497 http://www.agr.gov.sk.ca/DOCS/crops/integrated_pest_management/insects/grasshopperff.asp?firstPick=
Crops&secondpick=Integrated%20Pest%20Management&thirdpick=Insects
Cabbage seedpod weevil adults continue to be reported in southwestern Saskatchewan.
The threshold level for control at the early bloom stage is 3-4 per sweep. For more information on identification and
control of cabbage seedpod weevil refer to the following AAFRD link:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex2538
Check the following link for the 2006 cabbage seedpod weevil forecast map:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/prm10585
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.
« back