As long as crops are planted in the spring and harvested in the fall, farmers in western Canada will wage an annual battle against yield-robbing insects, such as grasshoppers and wheat midge. Thankfully, farmers on the front lines of that battle have a valuable and effective weapon at their disposal.
The Prairie Pest Monitoring Network (PPMN) is a prairie-wide monitoring system that predicts insect risks, monitors insect populations and offers advice on the best way to check for pests and keep them in check. The PPMN was established in the mid-1990s, with financial assistance provided through the Western Grain Research Foundation. “Essentially, what we’re trying to do is highlight insect-related issues for farmers, assess the risks associated with different insect pests and indicate the timeliness of in-field insect monitoring programs,” says Owen Olfert, a research scientist with Agriculture and Agri-Food Canada who helped to establish and design the network. “We’ve been going now since 1996 and the program has been expanding a little bit each year. “With the network in place, we are able to keep up with some of the new invasive alien insect species that are showing up and we are also able to monitor and forecast populations of established pests.”
According to Olfert, the decision to establish a prairie-wide pest monitoring network grew out of necessity. In the mid-1990s, the number of qualified entomologists involved in monitoring insect pests was declining. At the time, pest monitoring programs were being operated on a province-by-province basis, with limited cross-border co-ordination. Monitoring protocols also varied from one province to the next. To those involved in entomological research, the need for a more coordinated approach was obvious. “Entomological expertise was sort of declining and we had different groups in different areas that were sampling or monitoring insect populations, often using slightly different protocols from one another,” Olfert said. “We wanted to expand the scope of the monitoring and forecasting programs to cover the entire prairie region so this meant that we had to go beyond provincial borders because obviously insects don’t pay any attention to provincial boundaries.”
In the months and years that followed, Olfert and other experts gathered regularly to discuss insect monitoring methodologies, identify key insect pests and device a prairie-wide system that would give farmers a better chance of identifying and managing insect related risks. Today, close to a dozen insect pests are monitored by the network and regular updates are provided to the industry.
Weekly insect updates are available from May through August including risk warning maps and information on approved insect monitoring protocols, these updates can be accessed on-line at www.westerngrains.com. The weekly updates, along with updated risk maps and in-field monitoring protocols, are important tools for growers and agronomists who are in the field throughout the growing, Olfert said. “There are lots of larger producers out there today and it’s very important that they get out and do their own timely monitoring so they can control an infestation if it’s economically (beneficial) to do so.”
Scientists involved in the network also prepare annual insect pest summaries that are available to producers early in the new year. The annual summaries contain information that helps farmers make informed cropping decisions for the upcoming season. “We usually try to get that information out to growers by early January, in time for all the crop production shows, so that producers can take (insect) risk factors into account when they are planning their crop rotations,” Olfert said. In general, insects covered by the network can be broken down into three categories: native insects such as grasshoppers, invasive alien species such as wheat midge and swede midge, and migratory insects such as the diamondback moth.
Researchers who contribute to the network monitor not only insect populations themselves but also the environmental conditions that are conducive to the spread of migratory pests. Monitoring protocols that are used by the network are reviewed regularly. Factors that influence insect populations and densities are discussed annually along with economic thresholds, preventative measures and control practices that can be used by growers.
Jennifer Otani, PPMN co-ordinator based at Beaverlodge, Alta., said the network gives producers a more complete picture of insect pests that exist both regionally and on a prairie-wide basis. “It’s able to give some fairly current risk assessments for our economically important crop pests and it does so in a way that not only informs the producer of the risks but also gives them some really solid monitoring information that would support farmers’ efforts to monitor in their own regions,” Otani said. “Basically, it helps give producers more tools to assess their risk and put management plans in place so they are prepared to do that in-field monitoring that is so critical.”
Insect pests have been chewing into producers’ profits since western Canada was opened up for agricultural production more than 100 years ago. But not all insect pests are well known to growers. Every few years, there are newcomers to the prairies, such as the swede midge, which is becoming more common in parts of northeastern Saskatchewan. Some more common pests, including the orange blossom wheat midge, also expand their territory over time. Wheat midge is now a common insect pest throughout the Peace River region, said Otani. The PPMN helped to alert farmers in the Peace River area to wheat midge risks and allowed them to manage their operations accordingly.
For migratory pests such as the diamondback moth and the leaf hopper, effective risk assessments depend on systems that monitor environmental conditions such as temperature, moisture conditions and wind direction. “The bottom line is that most insect pests really react to the climate or the weather conditions,” said Olfert. “We have a number of insect pests such as grasshoppers that really like it hot and dry so if you have two or three years of drought in an area, you’ll invariably get an increase in grasshopper populations.” “Other insects, like the wheat midge are the exact opposite, They like more moderate, moister weather, calm winds, that sort of thing. So in years when those conditions are more common, we’ll see an increase in wheat midge populations.”