Weed & Pest braces for grasshopper influx

With predictions of a bad grasshopper season ahead, Crook County Weed & Pest has launch a program for larger properties that it hopes will keep the hungry insects from causing too much damage.

The district is also offering its assistance to landowners with smaller parcels who would like to tackle the potential influx.

“They are an intrusive, invasive little insect,” says Alycia Conroy-Davis, District Supervisor. “They eat everything.”

Hay, soy beans, alfalfa – it doesn’t make a difference, the grasshoppers are willing to eat it.

In fact, a grasshopper is capable of eating its own bodyweight in a day and will destroy plants as they do. It’s estimated that thirty pounds of grasshoppers can eat as much as a cow.

“Last year, the nymphal counts for Crook County were really high,” says Conroy-Davis. “Nymphals are young grasshoppers between stages one and three.”

Grasshoppers have seven stages between hatchling and adult, she explains. At the seventh and final stage, the grasshopper is about ready to lay eggs and die off.

“We want to get them between stages one and three, when they are molting before their wings come in,” she says.

The product that will be sprayed to control the grasshoppers, Dimilin ®, only works during this period of molting. It’s an insect-friendly choice, Conroy-Davis says, so it will not negatively impact other species such as bees or ants.

Dimilin also does not damage livestock or crops and is in fact, Conroy-Davis says, also labeled for alfalfa weevils, as well as types of caterpillar, moth and mormon crickets.

The potential for grasshoppers to be an issue this year was brought to the district’s attention by the Animal and Plant Health Inspection Services (APHIS), a federal program through the U.S. Department of Agriculture.

APHIS sends representatives to the county to survey the situation by calculating the number of grasshoppers per square yard, says Sophie Schwebke, Office Manager.

“They made a very calculated suggestion that we were going to have a big grasshopper problem this year, so this program that we’re doing actually started last July and August,” says Conroy-Davis.

However, Conroy-Davis explains that, much like the weather forecast, things can change unexpectedly. Anything from heavy rain to drought, or a hard freeze, can impact grasshopper numbers.

“Even though we have this program going right now, we could theoretically have a big freeze and it’ll kill them all,” she says.

If that were to be the case, the program will not go ahead.

“The money gets turned back to the government to be used elsewhere,” Conroy-Davis says. “It’ll go back in the pot and it’ll be allocated next year.”

On the other hand, grasshoppers are certainly making themselves known nearby.

“Montana is the biggest problem right now,” says Schwebke.

As reported by Montana Public Radio earlier this year, Wyoming’s neighboring state to the north was forecast to be the hotspot for grasshoppers in 2024.

Consequently, says Schwebke, “We couldn’t get any money from the federal government this year because of the amount of grasshoppers that are in Montana.”

That’s also a little too close to Crook County for comfort.

“Obviously, we border Montana, so up in our northwestern corner we have a higher count than, say, in our southeastern corner,” she says. “A lot of people have already signed up from that side because they already know that Montana is a big issue.”

Right now, Schwebke can usually be found hard at work at her keyboard, inputting data to the map that will be uploaded for the aerial applicator when the time comes to spray the Dimilin. This will later be refined to remove wooded areas, water and buildings from the spray areas.

The deadline by which this mapping must be complete is May 15. If you own property larger than 50 acres and would like to be involved in the program, it’s important that you contact Weed & Pest by the end of office hours on that day because you cannot be included after this cutoff.

You can, however, change your mind – being on the map does not lock you into the program.

For those landowners who do choose to spray, says Schwebke, the cost has been set at $5 per acre. This will be collected prior to the spray and will be placed in Escrow to address the matching funds needed for the Wyoming Emergency Insect Management grant funding of $58,231.

This is, however, the maximum amount that a landowner will pay. Weed & Pest has set this amount to ensure that costs can be covered but intends to refund the difference to landowners if the price tag comes in lower.

Once the spray is complete and the actual cost per acre is calculated, excess payments will be reimbursed by check, Conroy-Davis says.

The spray will be scheduled for the end of May or beginning of June, depending on the weather, and will take around a week to complete.

Spraying will be done using the RAATS system, which divides an area into a rows and will spray one and then miss the next. So, “Even though you’re doing 50 acres in the block, you’re only going to spray 25 of those acres,” says Conroy-Davis.

This is done for efficiency, because grasshoppers move around and will eventually pass onto bordering ground where the Dimilin is present.

If your property is under 50 acres but you would still like to protect your vegetable garden and flowers from a potential swarm of hungry insects, Weed & Pest is still available to help.

Smaller parcels have not been included in this program for purely logistical reasons, Conroy-Davis says, as buildings tend to take up a high percentage of the land.

“For those homeowners that want to treat, we can help them do that,” she says.

Dimilin is available from the district and can either be applied by the homeowner or with the help of a commercial applicator. If you wish to do your own spraying, you will need an applicator license; contact the UW Extension Office for more information on obtaining this.