Invasion of the grasshoppers

Insects have infested, devoured Routt fields


— Each step that Terri George took across her front lawn, a cloud of grasshoppers buzzed up around her knees. "It's like the yard is moving it's so creepy," said Terri George, who grows hay and alfalfa with her husband, Jeff George, at Elk River Ranch in Steamboat Springs. "You take a step and they just fly."

Terri George said the insects ate their way through the alfalfa fields two weeks ago and then flooded nearby parts of County Road 44 and her driveway. Now the grasshoppers have moved into the couple's lawn and pasture land, and George said she is worried that the irrigated hay could be next.

Jeff George's parents and grandparents both ranched land in Routt County, and he said he has never experienced or even heard stories about infestations of grasshoppers of the magnitude he's seeing now.

"My grandparents would probably tell you the dust bowl was better than this," he said.

Like the Georges, dozens of people in pockets of Routt and Moffat counties have seen exploding populations of grasshoppers in the past few weeks. In some of these regions, the insects have destroyed fields of alfalfa and hay, and have eaten grass lawns to the point that dirt is all that remains.

Grasshoppers hatch in the spring, and many usually die off due to late freezes or fungal diseases that attack the insects when the environment is moist.

But this year's drought has created perfect conditions for the grasshoppers to thrive.

The infestations are patchy, county extension agents said, but in areas where grasshoppers are dense, they are extremely dense.

Typically there are three or four grasshoppers per square yard. In parts of Routt and Moffat counties, more than 200 grasshoppers per square yard have been counted. That's about a million grasshoppers an acre, with each bug able to consume more than half of its own body weight in grass a day.

In Routt County, high densities of grasshoppers have been reported at ranches and farms along Twentymile Road, along a 10-mile section of County Road 44 and throughout an area of 15 square miles north of Hayden near the Cog Road.

In Moffat County, a couple hundred thousand acres south of Craig have seen high numbers of grasshoppers,

Moffat County Pest Management Supervisor Bruce Johnson said. Routt County does not have a pest management district.

Many of these grasshoppers are still young and will pose more of a threat to fields and crops once they morph into voracious adults, which can fly and cover more ground.

Driving down Twentymile Road, County Road 44 or even U.S. Highway 40 in Steamboat, the constant splatter of grasshoppers on car windshields is evidence that many of the bugs have already become adults.

Johnson, who has lived in Northwest Colorado his entire life, said he has never seen grasshoppers in these numbers.

"I've seen grasshoppers come and go but there's such a density that it's kind of unreal the ground is moving with them," he said. "They just mow stuff down. They're eating machines."

The last large-scale infestation in the West took place in the mid-1980s, but local farmers and ranchers said that densities then were nothing like they are in nearby areas now.

Johnson said another 50 square miles of Moffat County has been impacted by Mormon Crickets, which grow larger and faster than most species of grasshoppers but which are unlikely to make their way into Routt County. Recently in Dinosaur, some motels shut down for a day or two because they were covered with the crickets.

Greg Cox, a pest surveyor with the U.S. Department of Agriculture, did surveys of grasshopper densities around Steamboat Springs, Hayden and Craig last week. He said that the insects can easily eat entire fields.

"Ranchers have this range grass for their cattle to graze and that's why it's such a tragedy," Cox said. "Grasshoppers will destroy that grazeland and then cattle don't have food."

The grasshoppers create more difficulties for ranchers who are already facing dried-out pastureland and high-priced hay.

So far, extension agents said that Routt and Moffat are the only ones with extremely high densities of grasshoppers.

Counties such as Mesa and San Miguel have reported some areas with a dozen grasshoppers per square yard. Treatments to decrease the populations are usually considered when there are between 10 and 20 grasshoppers in a square yard.

Some local ranchers and farmers are beginning to use sprays or baits with insecticides to attack the grasshoppers. These treatments can decrease populations within 24 to 72 hours.

Scott Flower, managing partner of Wolf Run Ranch off Twentymile Road, said that so far 1,000 of the ranch's 2,500 acres have been affected by the grasshoppers. He said he has already sprayed areas twice and put out bait, and will continue to do so.

"We have an infestation of Biblical proportions," Flower said. "They just eat the leaf off of every blade of grass. We're concerned because we're just losing pasture."

On the ranch, Flower said there are about 500 head of cattle. He said he's now using his alfalfa fields for pasture and that he just hopes the cattle eat it before the grasshoppers do.

"We'll get by. It's not the end of the world," he said. "You do the best you can and pray for rain."

Flower said that doing the best job at stopping the grasshoppers also means thinking seriously about how to prevent another outbreak next year.

The outlook for the rest of the summer depends on weather and grasshopper food supply. Wet and cold weather would help decrease the grasshoppers' success. If the grasshoppers eat through the already scarce plant life and cannot find enough food, it is also likely that these patchy outbreaks will not grow. But it is also possible that the grasshoppers will find enough food to turn into adults that can then fly wherever they need to find food.

"These patchy areas certainly have the potential to blow up into much larger problems," said Jeff Lockwood, a professor of entomology at the University of Wyoming who has expertise in studying grasshoppers. Lockwood said that if swarms of flying adult grasshoppers are going to develop, they will probably be seen in the next two or three weeks.

"It's less likely that (grasshoppers) will run out of food, and more likely that a significant portion will find enough food to lay a whole nest of eggs," he said.

Depending on the species, each female grasshopper could lay between 300 and a thousand eggs at the end of this summer. What happens next summer would depend on next year's weather, Lockwood said.

There are some saying that outbreaks of grasshoppers occur in cycles of 15 to 20 years. Lockwood said that decades of research has not uncovered such a cycle, and that weather is probably the most significant factor in determining if an outbreak occurs.

A cold and wet spring next year would cut local grasshopper populations drastically, but another hot and dry spring could result in even greater densities.

Deb Babcock, who owns 35 acres of land off of County Road 44 and keeps a large garden, said she has seen lots of grasshoppers during the past two years but that this year the grasshoppers came in larger numbers and about three weeks earlier than normal.

This summer she has found headless daisies, chew marks in her sunflowers and mowed-down grass all due to the grasshoppers.

"They've chewed on just about everything out there," she said. "I don't think they're discriminating."

Susan Mikesell has run a ranch with her husband for the past 17 years near Hamilton, south of Craig. Mikesell said that with the grasshoppers, they've had to bale alfalfa early and give up on their grass hay.

"The (grasshoppers) have eaten a lot but it's kind of hard to tell how much damage they've done compared to just regular drought conditions. The hay is just not growing," she said. "It looks like it's going to be a long summer."

She has tried to find the bright side.

"At least the chickens are having a good time," Mikesell said. "There's plenty for them to eat."


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