June 5, 2013 – Issue 10

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  • Issues of the week

    Grass weeds in this canola field (above and below) in 2011 should have been hit pre-seed.

    Canola seeding is complete or nearly complete in most regions, and timely rains mean rapid crop establishment and reduced flea beetle threat for more regions — although see the Tweet of the Week below. Good growing conditions also mean heavy weed growth, especially in fields that did not get a pre-seed burnoff. Rates may need to be at the high end of the label for larger weeds, and grassy weed tank mixes may be required to get control and stay within label rate restrictions.

    Growers with unexpectedly good growing conditions may see the benefit in a fertilizer top up. The best method is to dribble on liquid or float on dry. Applying through the sprayer in a tank mix with herbicide is not the answer as rates are not high enough to be meaningful and full leaf coverage can cause serious crop damage.

    For those seeding in June, we have links to helpful articles on how to make a crop mature earlier, risks with late seeding, and broadcast seeding tips.

    Don’t forget to follow @CanolaWatch and the CCC agronomists on Twitter. Here’s our Tweet of the Week:

    Tweet of the week


  • Canola Watch quiz

    Quiz June 5

    What caused the pinched stems in these two plants?


  • Herbicide mixes may be needed on HT canola

    Perennial grasses are best hit with an early glyphosate application. Grasses are very sensitive to glyphosate, and produce leaf area more quickly and earlier in the season than broadleaf perennials. Grass weeds in this canola field (above and below) in 2011 should have been hit pre-seed.

    Take a look at the weed spectrum in each field before heading out to spray canola. In some cases, the straight partner herbicide may not be enough to take care of the weeds present, and tank mixes may be required. Read on for examples.


  • Can’t apply enough fertilizer with herbicide mix

    The best method is to dribble on fertilizer in a concentrated band rather than as a spray mist. Tank mixing with the herbicide, while it may be possible if the herbicide manufacturer approves, will not allow high enough rates to make any useful difference to the crop. The fine mist may also damage the crop.


  • Blackleg: Use fungicide only where blackleg is a known problem

    Here is a blackleg lesion on a canola leaf at the 6-leaf stage. Infection is showing up already in 2012 but lesions are harder to see on smaller plants. Source: Anastasia Kubinec, MAFRI

    Growers in areas where blackleg infection was known to cause yield loss last year may choose to apply fungicide early in the season.

    Here are factors that increase the blackleg risk. The more of these risk factors that apply, the greater the risk:

    —Tight canola rotation
—Using the same variety in the rotation

    —Yield loss to blackleg in previous years
—Using untreated non-certified seed

    —Poor brassica weed control in previous years. These weeds can host blackleg in non-canola years
—Moist soils and warm humid conditions
    —Lesions on leaves or cotyledons. These tiny lesions may be tricky to spot, and you probably won’t see many of them. When scouting, also look for blackleg pseudothecia (black spots) on old canola residue, which may still be present on fields with a tight rotation. Note: Even if you can’t spot lesions on new plants or black spots on old stubble, infection could still be happening.


  • Tank mixing herbicide with insecticide or fungicide

    When spraying for weeds it may be economical to add an insecticide or fungicide to the tank mix to hit any insects or disease (blackleg) that may be present at the same time. However, consider these four issues before proceeding:

    1. Is the tank mix supported by the product manufacturers? (See the next article for more on this.)
    2. Be sure the insect or disease is apt to cause economic damage or yield loss.
    3. Un-needed sprays put beneficials at risk.
    4. Sustainability — of both our management tools and our farming system.


  • How many tank mixes are too many?

    Growers must take extra precaution with any tank mix that is not identified and approved on the product label. The risks with off-label tank mixes include but are not limited to:

    —Damage to the crop
    —Antagonism or other reduction in control of one or more of the labelled pests
    —Residues in excess of the limits of those set for the components of the mix in the harvested grain
    —Creating a clogging lump in their spray tank
    —Violent reactions – explosion.

    The jar test may give the producer an indication of the last two problems (chemo-physical compatibility) but won’t tell them a thing about the biological compatibility of the components. The best source of information about all of the points is going to be the manufacturers of each of the components in the mix.


  • Insect update: Cutworm collection, insect traps

    Source: Prairie Pest Monitoring Network

    Cutworm activity has been light so far this year, with a few fields sprayed across the Prairies. We do expect to hear of more cases as crops start to emerge and feeding patches start to show up. Keep an eye out as many cutworm species will feed on canola, and each has its own cycle — as the table shows. Cutworms can feed well into July. While digging around for cutworms, collect them and send them into the survey. Read more to find out how you can help with the Prairie cutworm survey.


  • Crusting: Leave it be, hope for the best

    Only the few lucky seedlings that happened to be under a crack made it through this crust.

    There are no reliable solutions to crusting other than to wait for rain. Some growers have reseeded the worst sections of fields. A light harrowing might help if nothing has come through. Do a couple passes then assess whether canola seedlings are being ripped out of the ground. Harrowing too close to emergence can be harmful to a shallow seeded crop such as canola and may not be worth the risk.

    Using a roller may be worse than harrowing when soils are wet below the crust. Instead of cracking up the soil surface, a roller could turn the whole topsoil zone to concrete. Again, there is very little research on how to manage crusting. It’s trial and error.


  • 2-3 days of waterlogging deadly

    Excess water stress small

    Heavy rains in the past week left some Prairie canola fields under water. Canola is quite susceptible to water logging and shows a yield reduction after only 2-3 days with wet feet. Wet soils cause an oxygen deficiency, which reduces root respiration and growth. Root failure reduces nutrient uptake, and plants will eventually die unless drowned areas dry out quickly.


  • Late seeding tips

    This seed was floated on, then harrowed — in June 2011. We're still in early May.

    Growers hoping to seed their final canola acres this week or next week may want to consider the following tips to deal with a shortened growing season.


  • Ultimate Canola Challenge — Manitoba

    Here are the team leaders, from left to right: Shawn Cabak with Team CROP, Anastasia Kubinec with Team MAFRI, and Curtis Cavers with Team CCA.

    Final results are in. Which of these three team leaders had the highest profit margin?


  • Ultimate Canola Challenge – Alberta

    Gopher damage to canola leaves. Farming Smarter staff have been trapping gophers at the Lethbridge UCC site to keep damage to a minimum.

    Gophers are the latest threat at the UCC site in Lethbridge. This plant has suffered some feeding damage.


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