Canola Watch Report No. 6
June 10, 2009
In This Issue
Canola Continues to Battle Mother Nature
Broadcast Seeding Tips
Slow Growth and Development Continues
Frost – Patience Not Panic
How to Assess the Level of Frost Damage
Before Writing off the Crop
Foliar Feeding has Merit?
Things to Consider for the Re-Seed or Late Seeding Decision
Thin Stands Common
If Re-Seeding, Leave a Checkstrip
Flea Beetles – Stem Feeding Noticed
Flea Beetles – Be Vigilant with Thin Stands
More Cutworms Appearing
Worms and Other Soil Invertebrates
Cabbage Seedpod Weevils Spotted
In-crop Weed Spraying Next
Frost & Spraying – Wait if Possible
Spraying Tips
Be a Good Neighbor
Recruiting Disease Survey Participants
Questions and Contacts
This report is supported by each of the provincial canola grower associations. For more information on some of their activities check out the following links:
The Alberta Canola Producers Commission (ACPC) has developed an e-newsletter called Alberta Canola Connections. Sign up today http://www.canola.ab.ca/newsletter.html to receive the latest information on agronomy, marketing, coming events and more, or check out their website at http://www.canola.ab.ca/.
In Manitoba sign up for the Manitoba Canola Growers Association newsletter at
Canola Growers E-update or check out the website at http://www.mcgacanola.org/.
For information on activities in Saskatchewan, visit SaskCanola at https://www.saskcanola.com/.
Canola Continues to Battle Mother Nature
Environmental issues continue to dominate canola production across western Canada. Cool daytime temperatures with unseasonably cold nighttime temperatures occurred across the Prairies last week and over the weekend. All regions reported frost on multiple occasions with some areas experiencing frost four times last week. The most severe frost happened Friday night/Saturday morning where temperatures ranged from minus 1 °C to minus 7°C. The degree of frost is quite variable within an area as is the level of damage reported both within an area and within a given field.
Rainfall on Monday has again delayed seeding and reseeding in Manitoba. Broadcast seeding is expected to continue once fields are dry enough to support floatation equipment. Approximately 10% of the crop is yet to be seeded in Manitoba. In Saskatchewan and Alberta, where moisture is adequate for germination, emerged canola ranges from the cotyledon to the 4-leaf stage. Parts of east-central Alberta (east of Highway 21) and west-central Saskatchewan (Unity, Kerrobert, and Rosetown areas) missed the rains last week and require additional moisture soon. The extremely dry conditions continue to exist in the Castor, Coronation, Consort areas where canola is unable to germinate due to inadequate surface soil moisture. One of the local municipalities, the County of Paintearth, is in the process of being declared a disaster area.
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/crprpt090602
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
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
to the top
Broadcast Seeding Tips
The continued delay in seeding progress due to wet weather in Manitoba has led to many questions regarding the feasibility of broadcast seeding. In general, broadcast seeding is not recommended because it usually results in lower yields compared to drill seeding. However, producers faced with wet conditions that limit equipment flotation coupled with the risk of fall frost may wish to consider broadcast seeding in order to plant in a more timely fashion. Following are some tips for enhancing the success of broadcast seeding:
Increase seeding rates slightly to compensate for non-uniform seed depth.
Consider lightly cultivating (two to four cm) or harrowing to incorporate the seed into the soil if field conditions allow. However, avoid creating lumps or clods during cultivation or straw piles with harrows or cultivators.
If broadcasting fertilizer as well as seed, be aware that broadcast phosphorus is only about half as efficient as banded phosphorous. There also can be greater risk of denitrification on saturated soils, reducing N fertilizer efficiency. Adjust fertilizer rates accordingly, keeping in mind a realistic target yield based on the time of year and field conditions.
If broadcasting seed by aircraft, ensure that the seed does not get ‘blasted’ into the ground too deeply, thereby making emergence slow and difficult.
to the top
Slow Growth and Development Continues
Poor growing conditions due to the cold weather and repeated frosts prevailed across western Canada again last week. Canola growth and development was stalled. Canola ranges from cotyledon to 4-leaf stage and is delayed by at least two to three weeks.
In Manitoba, Growing Degree Days (GDD) to date range between 40 to 60% of normal (http://www.gov.mb.ca/agriculture/climate/wad00s00/cropwxrep.pdf).
The following maps show growing degree days thus far across western Canada: http://www.agr.gc.ca/pfra/drought/prtgdd_e.htm
The following link has more information on how temperature effects canola growth: http://www.canolacouncil.org/chapter5.aspx.
to the top
Frost – Patience Not Panic
Frost was widespread all across western Canada last week. From all reports, crop damage is quite variable – both within an area and within a single field. This is expected because many variables will affect a crop’s ability to withstand frost (duration of the frost, crop staging, crop residue, low lying areas, crop vigor, etc.) so the only way to assess the extent of frost damage is to get out and scout. You will notice symptoms of frost within hours, but plant survival and recovery potential cannot be confirmed for several days. After a frost, plant material will be wilted and discolored (whitening, yellowing). More severe damage will cause necrosis (browning or blackening) of cotyledons and leaves. Light frosts are often not lethal to the growing point (top, centre of the stem). This is where all new growth is initiated so if it is still green, the plant can re-grow.
The following link has useful photos on assessing frost damage in canola:
https://canolacouncil.merchantsecure.com/canola_resources/product37.aspx
to the top
How to Assess the Level of Frost Damage
To evaluate a field, walk an X or W path across the field and note all plants that will survive in a 1/4 m2 (3 ft2) area every 20 paces. This should be 50 to 100 samples. Record an observation from each sample. Calculate the percentage of the field that has adequate plant recovery. The frost may thin the stand only, especially in low lying areas. As a guide, a reasonable plant population early in the season is three to four plants/ft2. However, one to two plants/ft2 across the majority of a field can be adequate if managed carefully with today’s herbicide tolerant systems. Thin stands such as these can yield up to 90% of a normal stand seeded at an early date but will be later in maturity. Crops re-seeded late in the season typically yield less than earlier seeded that had thin stands. For example, one case study by the Canola Council of Canada showed a 7.4 bushel/acre advantage when a crop was not re-seeded after a frost. It likely will be better to leave a thinner stand (provided it is reasonably uniform) than take the risk of late re-seeding because maturity/early fall frost becomes a concern.
to the top
Before Writing off the Crop
Before making re-seed decisions consider the following:
Take a close look. Get down, way down, at ground level and look for signs of recovery. A plant with a green, intact growing point can still continue to grow. A magnifying glass will help zero-in on the tiny plant parts.
Scratch around and sc**** back crop residue or the top layers of soil. It is still relatively early in the emergence period so there may be plants that were protected from the frost beneath crop residue or beneath the soil surface (not yet emerged).
Scout fields thoroughly to determine the portion of a field that is affected. Perhaps only low-lying areas have been damaged. Or maybe the small percentage of the field affected enough to benefit significantly from re-seeding, does not warrant re-planting the entire field.
If possible, take a second look. Unless it is obvious that a crop is blackened and will not recover, wait three or four days and check again to see if plants have begun to show signs of recovery. Marking plants (with a wire flag or wire ring) will help follow the recovery of the same plants more closely.
Consult your local crop insurance agency for their policies to understand the implications of leaving a stand or deciding to re-seed.
to the top
Foliar Feeding has Merit?
There are reports of macronutrients and micronutrients being foliar applied to frosted, stalled crops to give the plants a boost. Canola Council of Canada agronomists are not aware of any scientific research to date here in western Canada that supports the economics of this practice. However, if growers do apply a foliar application, they should leave a checkstrip so they can evaluate the final yields. Council agronomists would like to follow fields with this treatment to harvest and use yield measurements to determine if the application was economical. If you are interested in having a Council agronomist help in evaluating your crop, please contact your local regional agronomy specialist listed at the end of this report.
to the top
Things to Consider for the Re-Seed or Late Seeding Decision
Re-assess the maturity of the chosen variety. It may be getting too late to plant longer season varieties based on the frost-free period remaining. If necessary, ask a local retailer to suggest other suitable varieties for the area. Keep crop insurance deadlines in mind. The crop insurance seeding deadline for Saskatchewan is June 20. In Alberta, deadlines are May 31 for full coverage and June 20 for limited coverage. Manitoba Agricultural Services Corporation has indicated that no extensions to seeding deadlines will be announced. Information on seeding deadlines for all zones and crops in Manitoba can be found at: http://www.masc.mb.ca/masc.nsf/crop_seeding_deadlines.html.
to the top
Thin Stands Common
Canola fields with low plant densities are more vulnerable to losses from insects, weed competition and environmental stresses such as fall frosts. Crops with low plant densities need to be managed more intensely. More frequent and intensive scouting for pests (insects and weeds) is critical because any losses are more likely to reduce yield. Action thresholds for pest control may need to be adjusted downward because the crop’s tolerance for damage is lower. Consider establishing a tramline by driving an ATV in an X or W pattern in the field to establish pathways for crop scouting.
More information on managing poor stands is available at:
https://canolacouncil.merchantsecure.com/canola_resources/product32.aspx
to the top
If Re-Seeding, Leave a Checkstrip
The decision to re-seed is not an easy one, especially this far into June. Ultimately it is the growing conditions for the remainder of the season that will determine if the decision to re-seed was correct. If you have made the decision to re-seed, leave a checkstrip, preferably in the centre of the field. This provides an easy way to get replication so at harvest you can make a yield comparison between the area not re-seeded and the two re-seeded areas on either side. The results of this on-farm experiment may be very valuable when wrangling with future re-seed decisions.
to the top
Flea Beetles – Stem Feeding Noticed
Flea beetle spraying was reported in many locations across the Prairies. Stem feeding was also noticed in a number of areas. Stem feeding is not a concern if small pitting is occurring. However, if significant stem feeding is occurring (impeding flow of water and nutrients in the stem or stems clipped off), then you may need a foliar insecticide. Canola is most susceptible to flea beetle damage during the cotyledon to 2-leaf stage. Flea beetle pressure is a significant threat this year for a number of reasons. 1) Seed treatment protection may be tapering off in some of the earliest seeded fields. 2) Thin stands are resulting in a higher concentration of beetles relative to the plant stand. 3) Frost and poor growing conditions have resulted in slightly damaged, slow growing plants that are more susceptible to flea beetle feeding.
to the top
Flea Beetles – Be Vigilant with Thin Stands
It is crucial that fields are scouted thoroughly and often. A heavy infestation on a stressed or thin stand can do significant damage in 24 to 72 hours. Be prepared in case additional control measures are required. The economic threshold for flea beetle control is when 25% or more of the cotyledons are damaged. However, if frost has already damaged some of the leaf material or thinned the stand, the action threshold may need to be adjusted. Evidence of feeding does not automatically mean spraying is warranted. Unwarranted spraying can cause harm to beneficial insects and can also contribute to the development of insecticide resistance. With current seed treatments, flea beetles must feed on leaf material and ingest the insecticide for control so some leaf pitting is normal. Flea beetles make their way into canola crops from the edges of fields. By catching a problem with flea beetles early, producers can often spray the perimeter of their fields and stop the infestation before it becomes widespread.
The following link provides more information on flea beetles:
http://www.gov.mb.ca/agriculture/crops/insects/fad09s00.html
The following links provide information on foliar insecticide flea beetle control in canola:
http://www.gov.mb.ca/agriculture/crops/insects/fad52s00.html
http://www.agriculture.gov.sk.ca/Default.aspx?DN=3eb86279-cec4-4718-b3a6-9b7e71736bf2
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/faq8031
to the top
More Cutworms Appearing
Reports of cutworms continued this week across western Canada. Cutworm damage often appears as bare patches showing up across the field. Plants in these areas will be wilted or dead and have been chewed off below the soil surface. Generally the pale western and red-backed cutworms are of economic importance in canola on the Prairies. Other cutworm species have been reported (e.g. Bronzed and Dingy) this year. Dingy cutworm larvae have a dull, dingy brown body with mottled pigmentation. A broad gray stripe runs along the back with light gray V shaped patterns on each segment. Fully developed larvae are one to 1 1/2 inches (25 to 32 millimeter) in length. Photos of dingy cutworm larvae and more information on cutworms in general can be found at:
http://www.gov.mb.ca/agriculture/crops/insects/fad06s00.html or
http://www.ent.iastate.edu/imagegal/lepidoptera/bcutworm/3936.105cwcompare.html
Use a garden trowel and soil sifter to collect cutworm larvae. Cutworms may be found in dry surface soil down to about two inches below the surface. The small, worm-like larvae curl up or attempt to hide in debris. Cutworm control may only be necessary in a limited area of the field. An insecticide is warranted when cutworms exceed three to four larvae per m2 and are actively feeding. Surface treatments should be applied in the evening, preferably under warm, moist conditions, because cutworms are active at night and these treatments will only control surface-feeding larvae. More information on cutworms is available at:
https://canolacouncil.merchantsecure.com/canola_resources/product22.aspx
to the top
Worms and Other Soil Invertebrates
While digging for cutworms, you may encounter other worms. Species in the enchytraeid family are pale white to grey, segmented worms and usually one to two cm (but can be up to five cm) in length. When magnified, these worms resemble earthworms. These creatures are beneficial insects that function in decaying organic matter and nutrient cycling. Saskatchewan Ministry of Agriculture has an archived Crop Production Newsletter with photos and descriptions of other soil invertebrates. To obtain a copy of the .pdf entitled Crop Production News – Volume 29 No. 3 with the section on ‘Worms and Other Soil Invertebrates’ e-mail your local Canola Council agronomist.
to the top
Cabbage Seedpod Weevils Spotted
Cabbage seedpod weevils have been reported in southern Alberta (Medicine Hat area). Owen Olfert, Agriculture and Agri-Food Canada - Saskatoon, is about to roll out the prairie-wide monitoring program for this season and we will relay the results as the season progresses. Although it is too early in the season to begin control measures for this pest, growers should watch carefully for weevils throughout southern Alberta and southwestern Saskatchewan (south of Highway 1) and be prepared to spray if populations remain high at early flower. Begin scouting at the bud stage with a sweep net to check for levels of both cabbage seedpod weevil and lygus bug.
to the top
In-crop Weed Spraying Next
Many producers were unable to do a pre-seed burn-off so it is critical to maximize efficiency with the first in-crop pass. The first step is scouting to determine weed species present and staging. Some growers are noticing that the grassy weeds are present and need to be controlled, whereas broadleaf weeds are slower to emerge. While research has shown that sequential applications are rarely economical, in this situation, it may be practical to split apply herbicides. For instance in the Liberty-tolerant system, it may be better to apply a graminicide earlier (for control of wild oats and volunteer cereals that are ahead of the crop) and wait to apply Liberty when more broadleaf weeds have emerged, rather than trying to rely on a single pass with a tank mix. This is especially true in drier areas where those early weeds are competing for precious moisture.
to the top
Frost & Spraying – Wait if Possible
Frost can interfere with herbicide performance and crop tolerance. After a light frost, it is important to wait until temperatures rebound in the middle of the day before spraying. After a heavier frost that caused damage (leaves are yellowed or necrotic), wait for plants to recover before spraying. New leaf growth should be visible on the crop to maximize crop safety and on the weeds to maximize control. Many herbicides have weather restrictions on their labels so check with local retailers or product providers for more recommendations. Always read and follow product labels.
to the top
Spraying Tips
Water quality is the key to achieving proper performance of many herbicides, particularly with glyphosate and many grassy weed products. The following links provide more information on spray water quality:
http://www.monsanto.ca/_pdfs/eblast/gk_19nov08.pdf
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex7573
Custom applicators (and growers in general) should double check to ensure the right product is being applied to the right field. Ensure legal land descriptions and field directions are 100% accurate to eliminate misapplication errors. Follow label directions for proper product rates and application techniques. Although good weed control has occasionally been reported in the past using reduced product and/or water volume rates, remember that the performance will be affected by factors such as growth stage and environmental conditions. Unless the product is applied according to label directions, the applicator will have little recourse in the event of poor weed control or crop damage.
Place a 4 ft X 6 ft tarp on the ground prior to spraying or simply shut off booms for a few yards to create a weed check. This will allow for performance comparisons. This is especially important since GPS technology has all but eliminated unintentional checkstrips!
to the top
Be a Good Neighbor
Spray drift can be costly (liability-wise) but also gives agriculture a negative image. Pay attention to boom height, nozzle selection, water volume, pressure, wind speed and direction, etc. Calibrate your sprayer before spray season begins. Information on sprayer calibration is available at the following link: http://www.omafra.gov.on.ca/english/engineer/facts/88-129.htm. Be a good neighbor and make certain the product applied hits the target and the target only. The following link has more information on managing spray drift: http://www.ag.ndsu.edu/pubs/plantsci/weeds/a657w.htm
to the top
Recruiting Disease Survey Participants
Faye Dokken, Provincial Specialist – Plant Diseases with Saskatchewan Ministry of Agriculture is looking for cooperators to participate in a canola disease survey this summer. Representatives from the Ministry would like permission to enter canola fields and collect a soil sample (for clubroot screening). While at the field, representatives will also take note of other canola diseases that may be present. Interested producers can contact Faye at (306) 787-4671 or Faye.Dokken@gov.sk.ca.
to the top
Questions and 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 Gutzke, Agronomy Specialist, Eastern Saskatchewan, gutzket@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
Matthew Stanford, Agronomy Specialist, Southern Alberta and Southwestern Saskatchewan, stanfordm@canolacouncil.org, 403-345-4852
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, Saskatchewan Canola Development Commission, 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.
June 10, 2009
In This Issue
Canola Continues to Battle Mother Nature
Broadcast Seeding Tips
Slow Growth and Development Continues
Frost – Patience Not Panic
How to Assess the Level of Frost Damage
Before Writing off the Crop
Foliar Feeding has Merit?
Things to Consider for the Re-Seed or Late Seeding Decision
Thin Stands Common
If Re-Seeding, Leave a Checkstrip
Flea Beetles – Stem Feeding Noticed
Flea Beetles – Be Vigilant with Thin Stands
More Cutworms Appearing
Worms and Other Soil Invertebrates
Cabbage Seedpod Weevils Spotted
In-crop Weed Spraying Next
Frost & Spraying – Wait if Possible
Spraying Tips
Be a Good Neighbor
Recruiting Disease Survey Participants
Questions and Contacts
This report is supported by each of the provincial canola grower associations. For more information on some of their activities check out the following links:
The Alberta Canola Producers Commission (ACPC) has developed an e-newsletter called Alberta Canola Connections. Sign up today http://www.canola.ab.ca/newsletter.html to receive the latest information on agronomy, marketing, coming events and more, or check out their website at http://www.canola.ab.ca/.
In Manitoba sign up for the Manitoba Canola Growers Association newsletter at
Canola Growers E-update or check out the website at http://www.mcgacanola.org/.
For information on activities in Saskatchewan, visit SaskCanola at https://www.saskcanola.com/.
Canola Continues to Battle Mother Nature
Environmental issues continue to dominate canola production across western Canada. Cool daytime temperatures with unseasonably cold nighttime temperatures occurred across the Prairies last week and over the weekend. All regions reported frost on multiple occasions with some areas experiencing frost four times last week. The most severe frost happened Friday night/Saturday morning where temperatures ranged from minus 1 °C to minus 7°C. The degree of frost is quite variable within an area as is the level of damage reported both within an area and within a given field.
Rainfall on Monday has again delayed seeding and reseeding in Manitoba. Broadcast seeding is expected to continue once fields are dry enough to support floatation equipment. Approximately 10% of the crop is yet to be seeded in Manitoba. In Saskatchewan and Alberta, where moisture is adequate for germination, emerged canola ranges from the cotyledon to the 4-leaf stage. Parts of east-central Alberta (east of Highway 21) and west-central Saskatchewan (Unity, Kerrobert, and Rosetown areas) missed the rains last week and require additional moisture soon. The extremely dry conditions continue to exist in the Castor, Coronation, Consort areas where canola is unable to germinate due to inadequate surface soil moisture. One of the local municipalities, the County of Paintearth, is in the process of being declared a disaster area.
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/crprpt090602
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
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
to the top
Broadcast Seeding Tips
The continued delay in seeding progress due to wet weather in Manitoba has led to many questions regarding the feasibility of broadcast seeding. In general, broadcast seeding is not recommended because it usually results in lower yields compared to drill seeding. However, producers faced with wet conditions that limit equipment flotation coupled with the risk of fall frost may wish to consider broadcast seeding in order to plant in a more timely fashion. Following are some tips for enhancing the success of broadcast seeding:
Increase seeding rates slightly to compensate for non-uniform seed depth.
Consider lightly cultivating (two to four cm) or harrowing to incorporate the seed into the soil if field conditions allow. However, avoid creating lumps or clods during cultivation or straw piles with harrows or cultivators.
If broadcasting fertilizer as well as seed, be aware that broadcast phosphorus is only about half as efficient as banded phosphorous. There also can be greater risk of denitrification on saturated soils, reducing N fertilizer efficiency. Adjust fertilizer rates accordingly, keeping in mind a realistic target yield based on the time of year and field conditions.
If broadcasting seed by aircraft, ensure that the seed does not get ‘blasted’ into the ground too deeply, thereby making emergence slow and difficult.
to the top
Slow Growth and Development Continues
Poor growing conditions due to the cold weather and repeated frosts prevailed across western Canada again last week. Canola growth and development was stalled. Canola ranges from cotyledon to 4-leaf stage and is delayed by at least two to three weeks.
In Manitoba, Growing Degree Days (GDD) to date range between 40 to 60% of normal (http://www.gov.mb.ca/agriculture/climate/wad00s00/cropwxrep.pdf).
The following maps show growing degree days thus far across western Canada: http://www.agr.gc.ca/pfra/drought/prtgdd_e.htm
The following link has more information on how temperature effects canola growth: http://www.canolacouncil.org/chapter5.aspx.
to the top
Frost – Patience Not Panic
Frost was widespread all across western Canada last week. From all reports, crop damage is quite variable – both within an area and within a single field. This is expected because many variables will affect a crop’s ability to withstand frost (duration of the frost, crop staging, crop residue, low lying areas, crop vigor, etc.) so the only way to assess the extent of frost damage is to get out and scout. You will notice symptoms of frost within hours, but plant survival and recovery potential cannot be confirmed for several days. After a frost, plant material will be wilted and discolored (whitening, yellowing). More severe damage will cause necrosis (browning or blackening) of cotyledons and leaves. Light frosts are often not lethal to the growing point (top, centre of the stem). This is where all new growth is initiated so if it is still green, the plant can re-grow.
The following link has useful photos on assessing frost damage in canola:
https://canolacouncil.merchantsecure.com/canola_resources/product37.aspx
to the top
How to Assess the Level of Frost Damage
To evaluate a field, walk an X or W path across the field and note all plants that will survive in a 1/4 m2 (3 ft2) area every 20 paces. This should be 50 to 100 samples. Record an observation from each sample. Calculate the percentage of the field that has adequate plant recovery. The frost may thin the stand only, especially in low lying areas. As a guide, a reasonable plant population early in the season is three to four plants/ft2. However, one to two plants/ft2 across the majority of a field can be adequate if managed carefully with today’s herbicide tolerant systems. Thin stands such as these can yield up to 90% of a normal stand seeded at an early date but will be later in maturity. Crops re-seeded late in the season typically yield less than earlier seeded that had thin stands. For example, one case study by the Canola Council of Canada showed a 7.4 bushel/acre advantage when a crop was not re-seeded after a frost. It likely will be better to leave a thinner stand (provided it is reasonably uniform) than take the risk of late re-seeding because maturity/early fall frost becomes a concern.
to the top
Before Writing off the Crop
Before making re-seed decisions consider the following:
Take a close look. Get down, way down, at ground level and look for signs of recovery. A plant with a green, intact growing point can still continue to grow. A magnifying glass will help zero-in on the tiny plant parts.
Scratch around and sc**** back crop residue or the top layers of soil. It is still relatively early in the emergence period so there may be plants that were protected from the frost beneath crop residue or beneath the soil surface (not yet emerged).
Scout fields thoroughly to determine the portion of a field that is affected. Perhaps only low-lying areas have been damaged. Or maybe the small percentage of the field affected enough to benefit significantly from re-seeding, does not warrant re-planting the entire field.
If possible, take a second look. Unless it is obvious that a crop is blackened and will not recover, wait three or four days and check again to see if plants have begun to show signs of recovery. Marking plants (with a wire flag or wire ring) will help follow the recovery of the same plants more closely.
Consult your local crop insurance agency for their policies to understand the implications of leaving a stand or deciding to re-seed.
to the top
Foliar Feeding has Merit?
There are reports of macronutrients and micronutrients being foliar applied to frosted, stalled crops to give the plants a boost. Canola Council of Canada agronomists are not aware of any scientific research to date here in western Canada that supports the economics of this practice. However, if growers do apply a foliar application, they should leave a checkstrip so they can evaluate the final yields. Council agronomists would like to follow fields with this treatment to harvest and use yield measurements to determine if the application was economical. If you are interested in having a Council agronomist help in evaluating your crop, please contact your local regional agronomy specialist listed at the end of this report.
to the top
Things to Consider for the Re-Seed or Late Seeding Decision
Re-assess the maturity of the chosen variety. It may be getting too late to plant longer season varieties based on the frost-free period remaining. If necessary, ask a local retailer to suggest other suitable varieties for the area. Keep crop insurance deadlines in mind. The crop insurance seeding deadline for Saskatchewan is June 20. In Alberta, deadlines are May 31 for full coverage and June 20 for limited coverage. Manitoba Agricultural Services Corporation has indicated that no extensions to seeding deadlines will be announced. Information on seeding deadlines for all zones and crops in Manitoba can be found at: http://www.masc.mb.ca/masc.nsf/crop_seeding_deadlines.html.
to the top
Thin Stands Common
Canola fields with low plant densities are more vulnerable to losses from insects, weed competition and environmental stresses such as fall frosts. Crops with low plant densities need to be managed more intensely. More frequent and intensive scouting for pests (insects and weeds) is critical because any losses are more likely to reduce yield. Action thresholds for pest control may need to be adjusted downward because the crop’s tolerance for damage is lower. Consider establishing a tramline by driving an ATV in an X or W pattern in the field to establish pathways for crop scouting.
More information on managing poor stands is available at:
https://canolacouncil.merchantsecure.com/canola_resources/product32.aspx
to the top
If Re-Seeding, Leave a Checkstrip
The decision to re-seed is not an easy one, especially this far into June. Ultimately it is the growing conditions for the remainder of the season that will determine if the decision to re-seed was correct. If you have made the decision to re-seed, leave a checkstrip, preferably in the centre of the field. This provides an easy way to get replication so at harvest you can make a yield comparison between the area not re-seeded and the two re-seeded areas on either side. The results of this on-farm experiment may be very valuable when wrangling with future re-seed decisions.
to the top
Flea Beetles – Stem Feeding Noticed
Flea beetle spraying was reported in many locations across the Prairies. Stem feeding was also noticed in a number of areas. Stem feeding is not a concern if small pitting is occurring. However, if significant stem feeding is occurring (impeding flow of water and nutrients in the stem or stems clipped off), then you may need a foliar insecticide. Canola is most susceptible to flea beetle damage during the cotyledon to 2-leaf stage. Flea beetle pressure is a significant threat this year for a number of reasons. 1) Seed treatment protection may be tapering off in some of the earliest seeded fields. 2) Thin stands are resulting in a higher concentration of beetles relative to the plant stand. 3) Frost and poor growing conditions have resulted in slightly damaged, slow growing plants that are more susceptible to flea beetle feeding.
to the top
Flea Beetles – Be Vigilant with Thin Stands
It is crucial that fields are scouted thoroughly and often. A heavy infestation on a stressed or thin stand can do significant damage in 24 to 72 hours. Be prepared in case additional control measures are required. The economic threshold for flea beetle control is when 25% or more of the cotyledons are damaged. However, if frost has already damaged some of the leaf material or thinned the stand, the action threshold may need to be adjusted. Evidence of feeding does not automatically mean spraying is warranted. Unwarranted spraying can cause harm to beneficial insects and can also contribute to the development of insecticide resistance. With current seed treatments, flea beetles must feed on leaf material and ingest the insecticide for control so some leaf pitting is normal. Flea beetles make their way into canola crops from the edges of fields. By catching a problem with flea beetles early, producers can often spray the perimeter of their fields and stop the infestation before it becomes widespread.
The following link provides more information on flea beetles:
http://www.gov.mb.ca/agriculture/crops/insects/fad09s00.html
The following links provide information on foliar insecticide flea beetle control in canola:
http://www.gov.mb.ca/agriculture/crops/insects/fad52s00.html
http://www.agriculture.gov.sk.ca/Default.aspx?DN=3eb86279-cec4-4718-b3a6-9b7e71736bf2
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/faq8031
to the top
More Cutworms Appearing
Reports of cutworms continued this week across western Canada. Cutworm damage often appears as bare patches showing up across the field. Plants in these areas will be wilted or dead and have been chewed off below the soil surface. Generally the pale western and red-backed cutworms are of economic importance in canola on the Prairies. Other cutworm species have been reported (e.g. Bronzed and Dingy) this year. Dingy cutworm larvae have a dull, dingy brown body with mottled pigmentation. A broad gray stripe runs along the back with light gray V shaped patterns on each segment. Fully developed larvae are one to 1 1/2 inches (25 to 32 millimeter) in length. Photos of dingy cutworm larvae and more information on cutworms in general can be found at:
http://www.gov.mb.ca/agriculture/crops/insects/fad06s00.html or
http://www.ent.iastate.edu/imagegal/lepidoptera/bcutworm/3936.105cwcompare.html
Use a garden trowel and soil sifter to collect cutworm larvae. Cutworms may be found in dry surface soil down to about two inches below the surface. The small, worm-like larvae curl up or attempt to hide in debris. Cutworm control may only be necessary in a limited area of the field. An insecticide is warranted when cutworms exceed three to four larvae per m2 and are actively feeding. Surface treatments should be applied in the evening, preferably under warm, moist conditions, because cutworms are active at night and these treatments will only control surface-feeding larvae. More information on cutworms is available at:
https://canolacouncil.merchantsecure.com/canola_resources/product22.aspx
to the top
Worms and Other Soil Invertebrates
While digging for cutworms, you may encounter other worms. Species in the enchytraeid family are pale white to grey, segmented worms and usually one to two cm (but can be up to five cm) in length. When magnified, these worms resemble earthworms. These creatures are beneficial insects that function in decaying organic matter and nutrient cycling. Saskatchewan Ministry of Agriculture has an archived Crop Production Newsletter with photos and descriptions of other soil invertebrates. To obtain a copy of the .pdf entitled Crop Production News – Volume 29 No. 3 with the section on ‘Worms and Other Soil Invertebrates’ e-mail your local Canola Council agronomist.
to the top
Cabbage Seedpod Weevils Spotted
Cabbage seedpod weevils have been reported in southern Alberta (Medicine Hat area). Owen Olfert, Agriculture and Agri-Food Canada - Saskatoon, is about to roll out the prairie-wide monitoring program for this season and we will relay the results as the season progresses. Although it is too early in the season to begin control measures for this pest, growers should watch carefully for weevils throughout southern Alberta and southwestern Saskatchewan (south of Highway 1) and be prepared to spray if populations remain high at early flower. Begin scouting at the bud stage with a sweep net to check for levels of both cabbage seedpod weevil and lygus bug.
to the top
In-crop Weed Spraying Next
Many producers were unable to do a pre-seed burn-off so it is critical to maximize efficiency with the first in-crop pass. The first step is scouting to determine weed species present and staging. Some growers are noticing that the grassy weeds are present and need to be controlled, whereas broadleaf weeds are slower to emerge. While research has shown that sequential applications are rarely economical, in this situation, it may be practical to split apply herbicides. For instance in the Liberty-tolerant system, it may be better to apply a graminicide earlier (for control of wild oats and volunteer cereals that are ahead of the crop) and wait to apply Liberty when more broadleaf weeds have emerged, rather than trying to rely on a single pass with a tank mix. This is especially true in drier areas where those early weeds are competing for precious moisture.
to the top
Frost & Spraying – Wait if Possible
Frost can interfere with herbicide performance and crop tolerance. After a light frost, it is important to wait until temperatures rebound in the middle of the day before spraying. After a heavier frost that caused damage (leaves are yellowed or necrotic), wait for plants to recover before spraying. New leaf growth should be visible on the crop to maximize crop safety and on the weeds to maximize control. Many herbicides have weather restrictions on their labels so check with local retailers or product providers for more recommendations. Always read and follow product labels.
to the top
Spraying Tips
Water quality is the key to achieving proper performance of many herbicides, particularly with glyphosate and many grassy weed products. The following links provide more information on spray water quality:
http://www.monsanto.ca/_pdfs/eblast/gk_19nov08.pdf
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex7573
Custom applicators (and growers in general) should double check to ensure the right product is being applied to the right field. Ensure legal land descriptions and field directions are 100% accurate to eliminate misapplication errors. Follow label directions for proper product rates and application techniques. Although good weed control has occasionally been reported in the past using reduced product and/or water volume rates, remember that the performance will be affected by factors such as growth stage and environmental conditions. Unless the product is applied according to label directions, the applicator will have little recourse in the event of poor weed control or crop damage.
Place a 4 ft X 6 ft tarp on the ground prior to spraying or simply shut off booms for a few yards to create a weed check. This will allow for performance comparisons. This is especially important since GPS technology has all but eliminated unintentional checkstrips!
to the top
Be a Good Neighbor
Spray drift can be costly (liability-wise) but also gives agriculture a negative image. Pay attention to boom height, nozzle selection, water volume, pressure, wind speed and direction, etc. Calibrate your sprayer before spray season begins. Information on sprayer calibration is available at the following link: http://www.omafra.gov.on.ca/english/engineer/facts/88-129.htm. Be a good neighbor and make certain the product applied hits the target and the target only. The following link has more information on managing spray drift: http://www.ag.ndsu.edu/pubs/plantsci/weeds/a657w.htm
to the top
Recruiting Disease Survey Participants
Faye Dokken, Provincial Specialist – Plant Diseases with Saskatchewan Ministry of Agriculture is looking for cooperators to participate in a canola disease survey this summer. Representatives from the Ministry would like permission to enter canola fields and collect a soil sample (for clubroot screening). While at the field, representatives will also take note of other canola diseases that may be present. Interested producers can contact Faye at (306) 787-4671 or Faye.Dokken@gov.sk.ca.
to the top
Questions and 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 Gutzke, Agronomy Specialist, Eastern Saskatchewan, gutzket@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
Matthew Stanford, Agronomy Specialist, Southern Alberta and Southwestern Saskatchewan, stanfordm@canolacouncil.org, 403-345-4852
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, Saskatchewan Canola Development Commission, 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.
Comment