Home / Canola Watch / Page 256
-
Our current economic threshold tables for lygus in canola may be too low when applied to current canola production systems across the Prairies. If a canola stand is healthy and growing fast, growers are reportedly doubling or tripling thresholds. Say the threshold is 10 per 10 sweeps, some growers are doubling that to 20 per 10 sweeps as the action…
-
Leafhoppers are more plentiful and carrying more aster yellows phytoplasm this year, but spraying is rarely effective. Bertha counts are starting to spike in some locations. Cutworms are still feeding in some locations, but the threat should be over for most regions…
-
Any stress can inhibit proper fertilization of the flowers. Common stresses included heat, drought, excess moisture, insects, herbicide damage, and nutrient deficiency. In many cases the cause may seem obvious, but it is often a good idea to investigate further to ensure there are no other contributing factors…
-
Growers are encouraged to check maturing crop for blackleg infection. It’s too late for fungicide to provide any benefit, but checking now can help plan for next year. Try to figure out why blackleg is worse than usual. It could be tight rotation. It could be use of a less resistant variety. Take steps to avoid that situation next time…
-
Noticing bud damage? Could be diamondback moth larvae, or many other possible causes. Regular rains in June and so far in July suggest an inflated risk for sclerotinia stem rot this year, especially in dense stands with good yield potential. Careful when making disease assumptions based on the low disease incidence last year…
-
Split applications, which are approved for some fungicides, may be worthwhile in some cases. For instance, if the sclerotinia stem rot risk is questionable at early bloom, growers could use a split rate and then wait to see if the second application is needed. Another benefit to the split is if the crop is uneven and the flowering period could…
-
Nitrogen and sulphur top ups at early flower are later than recommended but may pay off if fields are showing obvious signs of deficiency and crop yield potential is high…
-
If you have lygus bug and cabbage seedpod weevil in the same field and if they are both at 50% or more of their economic spray thresholds, spraying may provide an economic benefit…
-
Insects, heat stress, hail and sulphur deficiency can all cause bud discoloration and damage. Scouting closely for insects may be required to find out which might be the cause, especially if heat stress and hail can be ruled out…
Return to Canola Council Home
