Some bug troubles are in the past for Alberta growers, but others are just getting started.
“We already had a big run on flea beetles. That’s probably going to be one of the big stories of the year,” said Scott Meers, insect management specialist with Alberta Agriculture and Forestry.
“There’s also been way more cutworms this year, but those should be at their end. Late June is as long as I’ve ever seen them go.”
A mild winter combined with an early spring may have contributed to the large number of problem insects this year, with a second wave of pests coming on strong as things dried out.
“Some insects do extremely well in the dry conditions,” said Meers, who spoke at canolaPALOOZA in late June.
“Lygus do really, really well in dry springs because they get that first generation, and then the second generation grows up in canola. That’s the one that we worry about.”
The insect damage is also “amplified” in dry conditions because the plants don’t grow as well.
“We saw that with the flea beetles and, to a certain extent, the cutworms because the crop wasn’t getting as big as we expected it to be,” he said. “The cutworm damage was more severe because the plants weren’t as big and they ate more plants.”
Southern Alberta farmers can also expect a “big year” for cabbage seed pod weevil, he said.
“The early fields have really, really high numbers,” said Meers. “Based on what we’ve seen so far in the first in flower fields in southern Alberta, they will be extremely high.
“The early-flowering fields are probably going to need to be sprayed this year.”
The ideal time to spray for cabbage seed pod weevil is just past “bolting — 10 per cent flowers, or around when it nicely comes into flower. When you get that nice yellow look across the field is just about ideal.”
Cabbage seed pod weevils start laying eggs when the pods are three-quarters of an inch long, he said.
“You want to get in before that, and that happens quickly. Those flowers set pods within the first week.”