In this issue (click the bookmark
links below to move to specific sections of this
report):
Crop development/Swathing
progress | Combining
progress | Frost assessment
| Time of swathing related
to frost | Time
of swathing related to early planted canola
| Swathing tips
| Sclerotinia/Alternaria
| Straight cutting
| Pre-harvest glyphosate
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
Crop
development remains variable across most of
the Prairies. Cool weather continues to slow crop
development and delay swathing. In Manitoba, some
swathing of early seeded fields has continued,
with overall swathing progress at 15-20%. Swathing
progress in Saskatchewan ranges from 15% in parts
of the northwest up to over 80% in the Swift Current
area with 20-25% complete overall. Swathing in
Alberta ranges from 10-20% in central regions
to complete in the south. Overall crop development
in western Canada continues to range from several
days to three weeks behind normal, with the delay
increasing from west to east. Most areas received
more rainfall over the past week ranging from
a trace up to 5", making field conditions
very wet in much of Manitoba and parts of Saskatchewan
and the Peace region.
For current moisture condition maps across western
Canada, visit this PFRA page:
http://www.agr.gc.ca/pfra/drought/drprec7_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/crprpt040830.pdf
Additional moisture information for Alberta is
available from Alberta Environment at:
http://www3.gov.ab.ca/env/water/WS/data/precipmaps/weekly.pdf
Combining progress this past week was limited to parts of southern Alberta, southwestern Saskatchewan and the north Peace near Lacrete.
Assessment
of the frost of August 19/20 continues
across Manitoba, most of Saskatchewan (other than
the southwest) and parts of Alberta between St.
Paul/Bonnyville and Westlock. In Saskatchewan,
some of the hardest hit areas include Broadview,
Kelvington, Lintlaw, Lestock, Cupar and Wadena.
Damage assessment at this point indicates greater
damage than initially expected across many areas
of Saskatchewan, but damage in individual fields
ranges from very light to severe, with the cool
and wet conditions delaying the appearance of
symptoms. In Manitoba, the area enclosed in a
triangle ranging from Russell/Roblin in the northwest,
southeast to Killarney and west to the Saskatchewan
border reports the most damage. The amount of
frost damage is dependent on various factors including
crop stage, degree and length of frost, relative
humidity, and presence of rain or dew. For a more
detailed discussion on the effects of frost, refer
to the following SAFRR link:
http://www.agr.gov.sk.ca/docs/crops/frostdamage.pdf
The recent frosts continue to raise many questions regarding the time of swathing as it relates to the frost damage. In normal years, the optimum stage to swath for both yield and quality is up to 60% seed colour change on the main stem. However, the early frosts and abnormally cool weather may have altered the decision making process. The condition of the frost affected areas fall into three main categories, with appropriate swathing strategies for each category. Carefully assess each field and note which scenario the majority of the plants fall into.
Scenario 1: when there is little evidence of frost damage. The pods remain mostly green or tan-green, with few, if any, white spots on the outside of the pods. The seeds inside are mostly intact. Check the colour of the inside of the seeds as well. If the outside of the seeds are starting to turn, the insides should be yellow or a light lime-green. If seeds are still green on the outside and the inside of the seeds are still watery, the outside seed coats should remain intact and turgid. In these cases, leave the crop to continue to mature until further seed and or pod colour change occurs.
Scenario 2: when there is considerable
whitening of the outside of the pods for a majority
of the plants.
In this case, the pods will begin to shrink and
desiccate rapidly, and swathing should begin immediately
to reduce pod shelling and pod drop and conserve
any seeds in those pods.
Scenario 3: when there are
only white specks on the outside of the pods,
or only a few seeds in immature pods that are
not intact, or only a few seeds in the upper plant
parts are prematurely browning.
Premature browning occurs when the outside of
the seed has been damaged by the frost and the
inside of the seed remains dark green.
In these cases, the fields should be left and
monitored on a daily basis to evaluate further
crop changes. If no further damage is evident,
the remaining crop may continue to fill and mature.
If the seeds continue to deteriorate and/or pod
integrity declines, begin swathing to conserve
seed volume.
In all cases, monitoring should be done on a daily or bi-daily basis to evaluate further crop development and conditions, especially if warmer temperatures and sunshine return. When evaluating seed colour change, remember to keep in mind the condition of the crop canopy. Dense canopies often result from higher plant populations that limit the degree of side branching. Lower plant populations increase side branching, deflecting a greater portion of pod and seed development away from the main stems of the plants. In these cases, remember to monitor seed condition in the side branches as well, since a greater portion of the crop yield potential will reside in these branches.
Also, there have been a number of reports of crops that were planted early (late April or early May) where the seeds are all firm and intact for a week or longer, but little to no seed colour change has taken place. These fields may be good candidates to begin swathing (as early as 10% seed colour change), especially if the short-term weather forecast remains cool and/or cloudy. In many of these cases, the crops have been in the ground for up to 120 days and the seeds may be physiologically mature, although outside seed colour remains green.
Remember that with the cooler and wetter conditions, swath curing will take longer than usual. Expect to have the crop in the swath for at least three weeks to allow for curing and as much de-greening as possible before combining. Growers are encouraged to limit the degree of packing from swath rollers, to allow as much air movement through the swath as possible to facilitate curing and limit disease spread in the swath.
Sclerotinia
continues to be reported in most areas. Many cases
report late season infection, therefore the impact
on yield remains limited. For assistance in identifying
diseased plants, refer to the following page:
http://www.canola-council.org/sclerotiniasymptoms.aspx
Alternaria is reported in areas of east-central
Saskatchewan. Conditions remain conducive to disease
development due to the wet conditions.
There are a number of growers considering straight cutting their canola this year, including crops with frost damage. To be successful, consider the following factors:
Crop Canopy – the crop should be well knitted and slightly lodged to reduce the chance of pod shelling and pod drop. Remember that pod integrity (including petiole strength which influences pod drop) can be affected by the frost.
Disease – the crop should be relatively free from diseases including blackleg, fusarium wilt, sclerotinia and alternaria. These diseases all can cause premature ripening, which can in turn cause pod shattering.
Hail- Crops that were affected by hail are likely poorer candidates for straight cutting due to both the physical damage and the probability of greater disease infection through damaged tissue. Also, any late season hail often causes greater levels of damage to standing crops than swathed crops.
With swath stage approaching, growers should consider a valuable weed control tool for next year's crop--pre-harvest glyphosate. It is the most consistent and effective treatment for many perennial weed problems, providing an effective and economical alternative to in-crop control options. In early fall, perennial weeds are moving nutrients down into roots and rhizomes to prepare for winter. This period is when they are most vulnerable to herbicide translocation to the roots and better control is possible. If a Roundup Ready canola variety has been grown, a pre-harvest application will assist in some dry down of green weeds and offer perennial weed control, but it will not dry down the crop. Apply when the crop has 30% or less moisture content. At this stage, the pods are green to yellow and most seeds have turned from green to yellow or brown. Wait three full days (72 hours) after application before swathing to allow thorough translocation of the herbicide to ensure extended long-term weed control. Do not use pre-harvest glyphosate on canola seed crops.
There have been questions regarding the use of Reglone or glyphosate to speed up and even out crop development. Remember that application of either product results in eventual killing of the plant. Application of either product too early will cause similar problems to swathing too early, with the additional possibility of increased herbicide residues in the crop. Be diligent in following label directions on timing of product application.
Direct questions regarding this overall report
to John Mayko, Agronomic Research & Extension
Manager with the Canola Council of Canada at maykoj@canola-council.org
or ph/fax: 780-764-2593.
For specific questions regarding
regional issues associated with this report, consult
one of the following Canola Council of Canada
regional agronomists or provincial oilseed specialists;
For specific questions regarding regional issues associated with this report, please consult one of the following Canola Council of Canada regional agronomists or provincial oilseed specialists;
Derwyn Hammond, Agronomist,
Manitoba,
hammondd@canola-council.org,
204-729-9011
Rob Park, Manitoba Agriculture
& Food,
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
Bill Greuel, Saskatchewan Agriculture,
Food & Rural Revitalization,
wgreuel@agr.gov.sk.ca,
306-787-2756
Doug Moisey, Agronomist, Central
Alberta,
moiseyd@canola-council.org,
780-645-3624
Christine Mardell, Agronomist,
Peace River Region,
mardellc@canola-council.org,
780-518-1513
Nancy Muchka-Dahl, Agronomist,
Southern Alberta,
muchkan@canola-council.org,,
403-625-3406
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@gems9.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; Cargill; 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.