Topics for the Week

Eyes out for verticillium stripe (and other diseases too)

Despite being fairly new to the Canadian prairies, verticillium stripe is now widespread and impacting yield. According to the 2021 Manitoba Disease Survey, 30% of fields were infected, with 15% of plants in those fields showing symptoms. Verticillium stripe is easiest to identify near or after harvest when outer stem tissue shreds and peels and tiny microsclerotia (think black pepper) are visible on the tissue beneath. (Don’t be a silly one; scout for verticillium)

Make time to assess plants for other diseases at pre- and post-swathing too: cut stems for blackleg; inspect entire plants for sclerotinia stem rot and Alternaria black spot. Analyze roots and side roots for clubroot and other root diseases (note: clubroot galls may be large or tiny, and white or decomposing, brown and ‘peaty’ in appearance). Watch especially carefully in lower-yielding areas or fields and compacted zones. Where disease is confirmed, plan now to implement a prevention plan for future canola rotations. When considering cultivars for next year and beyond, disease and other major yield robbers should be the #1 factor in the decision-making process. If a disease’s identification is at all uncertain, send samples for testing. (Disease scout at pre- and post-swathing) (Disease id tips for pre-harvest scouting)

Set combine settings for max returns

Investing time to accurately scout crop maturity, thoughtfully assess harvest options, and effectively calculate (and then reduce ) combine losses can offer a significant boost in profit. Though combines running with optimized settings will lose some grain, aim to keep losses to 1% of yield: any lower will make harvest inefficient and any higher is an unnecessary waste of the crop. If you are running multiple combines in the same field, compare performance and settings.

Straight cut or swath? Here are some tips to help decide. Adjusting settings to reduce losses when switching from swathed to straight cut canola is especially important. Consider these changes for straight cutting canola:
1) speed up rotor RPMs to handle greener plant material,
2) take wires out of the concave to release canola seeds faster, and
3) pull back the rotor vanes to keep the crop inside the rotor for more rotations.

Post-harvest weed control

Fall is the preferred and easiest opportunity to get ahead of perennial weeds. Don’t scrimp. Good perennial control post-harvest typically requires higher rates of glyphosate than at pre-harvest because, even if perennial weeds have adequate time to regrow after cutting, the leaf area will be relatively small. Depending on specific annual weed concerns and next year’s crop rotation, consider tank-mixing with an additional mode of action that offers residual control into the spring. (What is the best time for fall weed control?) (Fall weed control and frost).

Applying herbicide to kochia in fall serves only as a dry-down agent because seeds are already formed. Growers dealing with multiple herbicide-resistant kochia biotypes should consider pre-emergent control for 2023. Watch land leases and other semi-public access points particularly carefully for invasive weeds, especially kochia. (Managing herbicide resistant kochia)

Minimize storage risk

Inconsistent growing conditions, mid- to later-season hail, and some disease issues mean some canola fields are nearing harvest with pockets of variable maturity. If most but not all of the field is ready to harvest, it can be difficult to decide between swathing, applying Reglone for dry-down, straight cutting and then conditioning, or simply waiting it out. In most cases, getting the canola into the bin is safer than waiting, though prioritize combining the most harvest-ready fields first. Sample often to know exactly what’s going into the bin to best assess storage risk factors. Even canola that tests dry can develop hot spots quickly: move grain if aeration isn’t available and follow these conditioning tips. (Green seed common questions)