Topics for the Week

Assess sclerotinia risk now

Several CCC agronomists report seeing lower incidence of sprayer tracks in canola fields than they’d expect, given the currently higher risk of sclerotinia in regions that have received good precipitation. Now is the time to seriously assess sclerotinia risk factors. Note: 50% flower is still within the range of most fungicide applications, but the application window is closing quickly.

If spraying the entire crop doesn’t offer economic return, it may be beneficial to consider protecting only the highest-value, most at-risk parts of the crop. There are many user-friendly field imagery technologies available that allow at-a-glance assessment of crop density. (Sclerotinia fungicide timing) (Precipitation map)

No quick fix for hail damage

Recent sporadic but significant hailstorms across much of the southern Prairies have left many producers looking for post-hail solutions. In fact, there is little to be done but wait: there is no benefit to applying any nutritional supplement or fungicide after hail unless an underlying nutrient deficiency or disease issue was already compromising the crop.

Canola generally recovers well after early season hail. The more advanced the crop, however, the more yield is likely to be lost to a hail event. While canola is resilient and can compensate for lost flowers, broken stems and even missing plants, hail after the 4-leaf stage typically produces delayed and variable crop maturity and may bite into yield. (Hail from 4-leaf to maturity)

To spray or not to spray for pests

Producing a profitable canola crop depends on timely and effective insect management… but only once the pest reaches economically damaging levels. To protect beneficial insects, reduce unnecessary insecticide use, and save money, do not spray for cosmetic damage. Instead, base all spray decisions on insect thresholds (while following label recommendations and keeping MRLs in mind). Regularly review insect thresholds as they can change. For example, there is no longer a threshold for lygus bugs at flowering as recent research shows no link between early season lygus feeding and yield loss. (Field Crop Protection Guide) (Insect thresholds drive profitable pest decisions) (Insect management in oilseed crops in Western Canada)

Spray to swath timing

An early reminder that insecticide and fungicide applications must meet pre-harvest interval (PHI) requirements, which is the minimum acceptable number of days between applying a product and swathing or straight-cutting the crop. While most fields are still several weeks away from PHI being an immediate concern, pre-planning maximizes options.

Keep it Clean’s Spray to Swath Interval tool makes calculating PHI easy: enter the intended product and crop type to calculate how long to wait after spraying, or enter expected product application and crop harvest dates to generate a list of product options that suit the intended timeline.

Keep it Clean will be hosting a pre-harvest tips and tools webinar Aug. 3 at 11:00am. For more information and to register, click here.