Topics for the Week

Protect that (high value!) canola from disease

BLACKLEG: Canola is at high risk of blackleg if it is in tight rotation, if the disease was evident in previous canola crops, and if the resistance genes in the variety don’t match the pathogen races in the field. Early control is critical – foliar-applied fungicide offers little benefit after the 4-leaf crop stage. (Blackleg scouting, ID and next steps) (Blackleg management guide).
SCLEROTINIA risk could be building in higher moisture fields. Because deciding whether or not to apply fungicide for sclerotinia is complicated, start considering now: what is the yield potential of the crop? How much recent and forecasted precipitation ? What other factors could influence infection? Effective sclerotinia control happens early: have products in the shed. CCC and AAFC are looking for volunteers to test a web-based sclerotinia risk assessment tool. More info is available here; email to sign up. (Sclerotinia stem rot) (Manitoba Ag sclerotinia treatment decision tool) (Research on improving sclerotinia disease control in edible beans and canola)

What’s the ROI on that new product?  

When canola prices are high, it can be tempting to wonder what additional in-crop products might boost yield. Before buying, ask: is there real return on investment in that new or new-to-you product? Is there unbiased data available showing performance? Think critically about efficacy; be discerning of information sources; and evaluate on-farm. Consider too: could there be downsides to tank mixing? Some tank mixes can scald leaves and even negatively impact certain products’ efficacy. A simple check-strip is absolutely necessary; replicated trials are better. Test-driving just an acre or two is recommended. Before ANY tank mix, jar test to ensure the mix doesn’t gel. *Top-dressing nitrogen will likely provide better ROI than spending $ on ‘latest and greatest’ products* (Tips for on-farm strip trials)

Top tips to optimize 1-pass herbicide

Only have enough product for one herbicide pass this year? To maximize herbicide efficacy:

  • Pre-scout to identify target weeds,
  • Consider how control strategies differ between different HT systems,
  • Apply herbicide ASAP: weeds present at earlier crop growth stages have more impact on yield, and bigger weeds are harder to control,
  • Manage less-than-ideal spray conditions,
  • Don’t scrimp on water and apply at the recommended label rate, and
  • Consider tank-mix products to bump-up single-pass control (or – in the case of weeds like wild oats – consider a later pass with a cereal-specific product).
    (Second pass herbicide why and when)

What if Mother Nature doesn’t play along

Though it’s hard to stand by as a crop gets pounded by hail or drowned in standing water, patience is the best – and only – option. Seedling canola can often recover from hail or excess moisture.
Weed control is an important consideration on unseeded acres. Rather than spending significant dollars on herbicide, consider cover cropping. (Note: weeds themselves can be an effective cover crop so long as they don’t go to seed.) Should adding drainage be on the fall to-do list so low spots can be more productive next year?