Powder River Examiner -

By PR Extension Office

More than seventy-five landowners attending the recent Extension Ag Winter Series in late January learned that the double-digit sub-zero temperatures we suffered in January likely had no effect on the grasshopper eggs laid in pods in the soil, according to MSU Extension Powder River Agent Mary Rumph.

“I’ve been hearing optimism that the frigid cold spell was at least beneficial for destroying grasshopper eggs, however, according to Gary Adams, State Plant Health Director for the USDA Montana APHIS, the eggs were likely not impacted,” said Rumph. Adams presented the biology of grasshoppers and shared the nuts and bolts of the APHIS Rangeland Grasshopper Suppression Program.

Landowners can enter a cooperative service agreement with APHIS for treatment this summer, depending on the availability of funds for the program, explained Adams. The agreements are available directly through APHIS or at the Powder River Extension Office. Funding is limited and will be allocated on a first requested basis. Landowners do not pay until services are rendered, said Rumph.

Key points for planning a grasshopper control program for 2024 include:

• Treatment areas with a minimum of 10,000 acres of rangeland are necessary (blocks can be mapped based on landowner interest).

• Dimilin is the product used at 1 oz./Acre. It is a growth regulator that is effective on insects with an exo-skeleton; it is not harmful to bees or birds;

• RAATs (Reduced Agent Area Treatment) is utilized, an aerial swath treatment;

• Treatment with Dimilin must be done at the third instar (which normally occurs in mid to late June);

• No treatment will occur if the population doesn’t exceed the threshold for control based on early June surveys.

Please contact Powder River Extension for more information at 436-2424 or Gary Adams at 406-657-6282.