Story Posted: October 05, 2011

Canola Watch: Harvest high green, More clubroot

Topics for the month: Green seed is the major issue for most growers waiting to finish canola harvest. Green seed levels in some fields are not dropping and are unlikely to drop further without a long period of moist and warm weather. Growers may have to accept the losses, combine now to salvage the quality they do have, then start shopping for buyers who will take delivery soon.

Growers in the Peace need a string of dry warm days to finish off the crop.

Clubroot has been confirmed in two canola fields in Saskatchewan. Click here to read the SaskCanola media release.

Check all canola bins. Canola with any of the following is at higher risk of spoilage: high green, high oil, high temperature, high moisture, high dockage. Combinations of these factors will make stored seed even more unstable.

Crop and weather update
Peace (B.C. and Alberta): Harvest is nearly complete in the north, two-thirds complete in B.C., and further behind in central and east regions. Very little has been combined in the extreme east. Cool and moist conditions continue to delay dry down.

Alberta: Southern Alberta is 95% harvested. Central Alberta is nearly complete on the east side and about two thirds complete on the west side. Alberta crop report.

Saskatchewan: Most of the province has finished harvest. Many of the fields yet to be combined have higher green seed levels. Saskatchewan crop report.

Manitoba: Harvest is nearly complete, except for the odd late seeded field and areas around The Pas. Manitoba crop report.

Do you have time for high-green canola to cure?
Growers waiting for green seed levels to drop before combining should weigh the risks. If you do get enough rain and high humidity to lift canola moisture back above 20% to restart the green-clearing process, will that canola ever dry back down enough for timely and efficient harvest? With the long cool nights of October, this becomes less likely.

The best bet may be to harvest the crop now to maintain the yield and quality that's there, and start looking for buyers. Click here for a list of companies that buy high-green canola. Because canola with a higher percentage of green seeds tends to spoil faster, early delivery is ideal. Green canola is more valuable than heated canola.

Don't want snow. The longer you leave canola at this time of year, the higher the risk of snow, which will further delay harvest. If canola cannot be harvested until next spring, high green will not be the only quality issue. When canola overwinters in the swath, molds build up on the seed, free fatty acids build up in the oil, overall bushel weight drops, and yield loss results from shelling and rodent feeding. The result is lower yield and often a downgrade to "sample."

High oil, high green = higher heating risk
Large-sized canola seed and canola seed that filled during cool and moist conditions may have higher oil content than usual. This changes the safe storage dynamic.

Research is currently looking into the effect of higher oil content on stored canola under western Canadian conditions. However, based on research from other countries like Australia, it is estimated that for every 1.0 percentage point increase in oil content, canola should have 0.1 percentage points lower moisture for safe long-term storage. For example, if canola with 40% oil is safe at 8.5% moisture, then canola with 45% oil should be stored at 8% moisture. This assumes the temperature for each is below 15 C and stable.

High green will also increase the storage risk, even if the canola is dry and cool. The safest bet is to deliver sooner than later. If that is not an option, proper conditioning and frequent monitoring for heating and spoilage are crucial until it can be delivered.

Keep the fans on for all canola. No matter the oil content, green count or moisture level, keep canola on aeration until bin core temperatures have dropped to less than 15 C and are stable. If the bin doesn't have aeration, monitor the canola closely and be prepared to rotate grain every couple weeks. Click here for more on this topic.

Clubroot intensifies, check fields
Two cases of clubroot have been confirmed in Saskatchewan. Growers in fringe areas where clubroot is at low levels or has not yet been detected are encouraged to check their fields. The photos below show decaying clubroot galls — typical of what galls look like this time of year. Noticing the disease before it gets serious is an important step in long-term clubroot management. Click here for a news release on what to look for and what to do. Clubroot.ca has more detail on all aspects of clubroot management.

If clubroot is present but undetected, then growers, custom operators and whomever else visits the field can spread infested soil throughout the farm and to neighboring farms that much faster.

	Example of clubroot galls found at harvest time.

	Example of clubroot galls found at harvest time.

	Example of clubroot galls found at harvest time.

	Decaying clubroot galls.

	Decaying clubroot galls.

Clean equipment to limit disease spread
Growers considering tillage for fall weed control should clean equipment between fields to limit disease (and weed seed) spread. Tillage equipment carrying soil and stubble from field to field can also carry soil- and stubble-borne diseases such as clubroot and blackleg.

In the case of clubroot, 99% of spores can be removed by physically removing any mud or soil from tires, openers, etc. Pressure washing and a rinse with bleach or other industrial cleaning solution can remove most of the rest.

Visit clubroot.ca for more on equipment sanitation and other prevention measures.

Why is desiccated canola not drying down?
If canola is not drying down after a Reglone application, the following may provide some insight as to why:

Reglone is a contact herbicide (only kills what it contacts) and is registered in canola to dry green material to facilitate harvest. "Contact" means that only the parts of the plant that are contacted by the spray solution will be desiccated. Coverage is the key to good activity.

Some parts of the plant will still remain untouched even with the highest water volumes. Reglone is activated by light reactions in the plant, so applying in darkness allows the active ingredient to move deeper into plant tissues before being activated. Applications made in bright sunshine are active as soon as the spray hits the leaf surface and any further spread is immediately stopped. To allow the Reglone to spread as far as possible within the plant before activation, apply under cloudy conditions or in the evening.

The Reglone label says to wait 7 to 10 days before combining canola and mustard, but do not wait longer than 14 days. The herbicidal activity of the Reglone will occur quickly, within minutes of the treated plant's exposure to sunlight, and continue for a few hours. This is evident by the water soaked appearance of treated plant surfaces shortly after application, as the liquid contents of the plant's cells leak from ruptured membranes. In the following 7 to 10 days, the tissues affected by the Reglone application will continue to dry. Reglone is unlikely to provide any additional desiccation benefit beyond 10 days. Continuing to wait for further desiccation from this application will likely just put the pods that were desiccated at risk of shelling.

Spread residue evenly in fields planned for canola in 2012
Good canola stand establishment, especially in direct seeding situations, starts with straw and chaff management for the previous crop. Spreading residue evenly across the field is critical.

If the combine can't spread cereal chaff and straw evenly across the width of cut, one option is to drop the straw and bale it. Another option is to use a heavy harrow to spread the straw. Delay heavy harrowing until the straw is dry enough to allow even distribution and minimize piling up and bunching of the straw.

One exception to this strategy for managing crop residue may be fields where a small patch of clubroot has been identified, as heavy harrowing may move enough infested soil to spread those clubroot spores throughout the field.

Click here for the library of residue management articles from the Reduced Tillage Linkages website.

What weeds will you be dealing with next year?
Growers don't have much time left to control weeds in fields planned for canola next year. Click here for an article on fall weed control tips from the previous Canola Watch. Click here for a radio interview with CCC agronomy specialist Dan Orchard on fall weed control.

Cleavers seem to be getting worse again in some areas. Growers who saw cleavers in their cereal crops this year will want to consider a management plan for cleavers in canola next year. This plan may include fall spraying and choosing a herbicide tolerance system that provides the best control.

GM Canola: The Canadian Experience
Agriculture and Agri-Food Canada research scientist Hugh Beckie et al published an article called "GM Canola: The Canadian Experience" in Australia's Farm Policy Journal, published by the Australian Farm Institute. The authors examined the agronomic, economic and environmental impacts of genetically modified (GM) herbicide resistant (HR) canola after 15 years of cultivation in Canada.

Key findings:

• Rapid adoption of GM canola is due to improved weed control, greater yields, higher economic returns
• GM canola reduced the environmental impact of herbicides compared to non-HR canola
• No change in volunteer canola problems, with the exception of no-till systems where glyphosate was used alone
• GM canola has not reduced weed species biodiversity
• HR canolas provided new in-crop modes of action assisting in the delay of weed resistance

Here is the whole article: 20110309_FPJ_Aut11_Beckie.et.al

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