Grasshoppers are out there, and, in some areas in the Prairies, in large numbers.
It’s important to get into your field and scout, not only for populations, but also as a friendly reminder that not all hopping insects are grasshoppers.
There are other insects in the field that hop and jump but aren’t grasshoppers, says Jeremy Boychyn, agronomy research extension specialist with the Alberta Wheat and Barley Commissions, so you need to know what you are seeing.
Also, you aren’t going to want to go into the field empty handed, says Boychyn. He personally likes to bring three tools with him: his stadium counter, a metre-long shovel, and of course, his sweep net.
Before we make any management decisions, it’s crucial to know your fields, know the area, and have an accurate count, he says.
“The way we count grasshoppers is to pace out 50 or 100 meters by about one meter. So we bring our one meter tool, and walk 50 or 100 meters based on maybe fence posts, and how long they are. And then we’ll count the amount of grasshoppers that we see,” Boychyn explains. “So I’m holding [the shovel] to get a visual of what one meter is, and I’m walking forward. As I’m seeing grasshoppers jump, I’m counting 1-2-3. And then when I get to the end of that 60 meters, I divide that number by 50 to get how many grasshoppers I encountered per meter squared.”
From there, he then checks if the number is within the economic or action thresholds, which as Boychyn explains, ranges from eight to 12 grasshoppers in cereal crops.
“Above that, we definitely want to be taking control if we’re seeing our crop is already in high stress, so in drought situations, maybe we want to take action even slightly before that.”
Check out the full video on scouting for grasshoppers in this Wheat School, below: