What has damaged these flowers…?
Under various conditions the past decade, some canola fields have exhibited stunting and strange deformities in bud clusters — as demonstrated in the photo gallery in this article. The cause remains a mystery.
Grasshoppers may be above thresholds in some fields. The nominal threshold for grasshoppers in canola is 8-12 per square metre, although the higher end of that range may be more appropriate in a typical canola crop. Grasshoppers are often at higher numbers at field margins, making a targeted spray possible. Scout to see where that line is.
Hot days (28-30°C and up) and warm nights (16°C and up) from bud to mid-flowering stages can have a devastating effect on canola yield.
Crop staging comes into play for herbicide, insecticide and fungicide timing. So crops with plants at various stages — some at flowering, some barely at the bud stage, for example — present a challenge when deciding when to spray.
Moisture is the key risk factor for sclerotinia stem rot. Without moisture before, during and after flowering, disease severity and the return on investment from fungicide will be lower than if moisture is present all through these periods. Moisture can come as rain, dew and/or humidity above 80%.
Sclerotinia stem rot and cabbage seedpod weevil control timing depends on flowering stage. This article will help you estimate 10%, 20% and 50% flower.
A for the is up and running. The video gives a quick introduction to the site and how to use it. Research is continually being added to the hub. Take some time and check out its features.
International Rapeseed Congress – July 5-9, Saskatoon, SK
Crop diagnostic school — July 7-9 and 14-17, Carman, MB
Making the grade — July 28, Olds, AB
Crop diagnostic school — July 28-30, Outlook, SK
Canola Discovery Forum — October 27-28, Canmore, AB
Read more for registration links
Canola is quite resilient to light hail at up to 20% flower. The crop can flower longer to compensate, and may recover with only minimal to moderate yield loss. Canola has also shown remarkable recovery from more intense hail at 20% flower. However, a crop flattened by hail is unlikely to recover. If regrowth occurs, which is possible, plants are set back so far that maturity becomes a major factor.
Canola Watch is a free, unbiased, timely and research focused weekly newsletter from the Canola Council of Canada Crop Production Team
You can subscribe to Canola Watch and search all the articles on the Canola Watch website