County at centre of insect issues

By Garrett Simmons
Southern Alberta Newspapers
Insects are really bugging agricultural producers in The County of 40 Mile.
That was the general theme for Scott Meers, insect management specialist for Alberta Agriculture and Rural Development, who mentioned the area has been a hotspot for pests in southern Alberta.
Speaking last Tuesday at the Agronomy Update 2015 conference at Lethbridge Lodge, Meers said the area has experienced a perfect storm for insect development.
“It seems 40 Mile is at the centre of a lot insect issues right now,” he said, as slide after slide noted the proliferation of pests in the region, including the diamondback moth, which blew into the area last year from the United States. “We did have trouble in Foremost.”
He added that region recorded 20-30 of the moths per square foot in some areas, as Meers went on to say wheat midge was also a problem there in 2014 on irrigated wheat.
Another wet year will exacerbate the problem, particulary in central Alberta, but in the south, irrigated fields will be susceptible. Midge-tolerant wheat, proper crop rotations and management packages can lessen the blow, he added.
“If you don’t use proper rotations and proper agronomics, you can put yourself in a real bind.”
Wheat stew sawfly may also be an issue in 2015 for one area in the south — guess which one?
“Unless you’re in 40 Mile, you’re probably not going to worry about it,” said Meers. “We are seeing an increase, so as your wheat heads out, watch for it.”
For southern Alberta in general, Meers cautioned pests may be due for for a bit of an outbreak, simple due to the nature of crops being grown.
“We’re seeing more acres in hemp and we’re seeing a big boom in faba beans, and those are going to raise significant insect problems as those crops become more established.”
Already, a few pests appear to be making strides in Alberta, like the pea leaf weevil, which enjoyed a resurgence in 2014. Meers added southern Alberta was hit hard, as some locations surveyed had plant damage measured at over 81 notches per plant.
“That’d the first time we’ve ever seen that intense feeding. We’ve never had that range before. That’s new to us.”
Another warm spring could intensify the weevil problem, according to Meers, who added the insect loves faba beans.
Grasshoppers could also be a problem in 2015.
“All through southern Alberta we’re seeing increases in grasshopper numbers. We’re on the verge that if we see perfect conditions in the spring, we will need to spray for them.”
Cabbage seed pod weevil is another pest here to stay, Meers declared, as it will continue to be an issue for canola growers.
And according to Hector Carcamo of the Lethbridge Research Centre, the weevil is particulary destructive for early-seeded canola, particulary crops seeded in late-April, according to a sample of fields the research centre tested.
“Forty per cent of those fields had weevils over the economic threshold,”?he said, while planted later in May, faced issues with lygus bugs instead. “If you plant late, you’re synchronizing your crop cycle with the damaging cycle of the lygus bugs.”
He cautioned growers to be careful about spraying for the pests, and mentioned only fields where 2-3 weevils are found per sweep, at the early-flower stage, should be sprayed. For lygus bugs, he suggested growers scout for them at the end of flowering and early-to-mid pod stages, and even if the insects are found, Carcamo said spraying may not be in your best interest.
“Keep in mind, lygus bugs have quite a few beneficial insects,”?he said, and added rainfall, which pushes the bugs to the surface, is also a natural cure.

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