Grasshopper numbers expected to be low for 2007

Source: Saskatchewan Agriculture and Food

Early indications project that Saskatchewan is in for a relatively light year on the grasshopper front.

That appears to be the overall trend outlined in the 2007 Grasshopper Forecast map developed by Saskatchewan Agriculture and Food (SAF) and the Saskatchewan Crop Insurance Corporation (SCIC). The map estimates that the general risk to cereal crops will be “none to very light” across most of Saskatchewan this year.

The predictions are based on adult grasshopper populations observed during a 2006 fall survey conducted by SCIC field personnel. The survey included approximately 1,150 sites, and attempted to determine the number of adult grasshoppers potentially capable of reproduction and egg-laying.

This information was then used to provide an estimate of eggs that could survive the winter and hatch the following spring, presenting a potential risk to crops for the 2007 growing season.

The warm, dry weather Saskatchewan experienced last summer and fall was conducive to an increase in grasshopper numbers; however, SAF Insect and Pest Management Specialist Scott Hartley said the grasshoppers are still recovering from past crop seasons that significantly reduced their overall population.

“Their population had already been decimated by two very poor years for grasshoppers, and it requires a rebuilding process,” he noted. “As a result, they’re starting from a smaller base.”

“The biggest single factor yet to be determined will be environmental conditions come spring,” he explained. “A number of factors will come into play, but it all revolves around what that springtime climate is going to be like.”

Although the province-wide prognosis looks favourable, Hartley says there are still pockets to watch out for.

“Areas in both the southeast and southwest were identified with a few light infestations that could develop into something more serious. An area of moderate risk is also indicated near Fox Valley in the southwest,” he stated.

“Producers also need to be extra careful on crops that are more vulnerable, because they take lower numbers of grasshoppers to cause a problem,” Hartley added. “On lentils, for example, even a count as low as two grasshoppers per square metre can cause economic damage. Flax is another crop in which, as green bolls develop, even a low number of grasshoppers can impact the yield.”

Hartley emphasized that the grasshopper forecast and map does not provide a definitive field-by-field projection, and farmers will still need to monitor for grasshopper populations as the year progresses.

“Overall, I think the grasshopper forecast is generally good news. The populations are much lower, so we don’t expect it to be a huge issue,” he said. “But there are some isolated areas to watch out for, where the numbers could be sufficient to do economic damage.”

The 2007 Grasshopper Forecast map can be found on the SAF website at www.agr.gov.sk.ca. Updates on the status of grasshopper populations in Saskatchewan will also be available during the production season through the SAF Agriculture Knowledge Centre at 1-866-457-2377.

For more information, contact:
Scott Hartley, Insect/Pest Management Specialist
Saskatchewan Agriculture and Food
Phone: (306) 787-4669